OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH. D. RAVINDRA BABU B. Tech. (Agril. Engg.

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1 OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH D. RAVINDRA BABU B. Tech. (Agril. Engg.) MASTER OF TECHNOLOGY IN AGRICULTURAL ENGINEERING (PROCESSING AND FOOD ENGINEERING) 2012

2 OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH BY D. RAVINDRABABU B.Tech. (Agril. Engg.) THESIS SUBMITTED TO THE ACHARYA N. G. RANGA AGRICULTURAL UNIVERSITY IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF MASTER OF TECHNOLOGY IN AGRICULTURAL ENGINEERING (PROCESSING AND FOOD ENGINEERING) CHAIRPERSON: Er. M. MADHAVA DEPARTMENT OF AGRICULTURAL PROCESS AND FOOD ENGINEERING COLLEGE OF AGRICULTURAL ENGINEERING BAPATLA ACHARYA N. G. RANGA AGRICULTURAL UNIVERSITY 2012

3 DECLARATION I, D. RAVINDRA BABU, hereby declare that the thesis entitled OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH submitted to the Acharya N. G. Ranga Agricultural University for the degree of Master of Technology in Agricultural Engineering is the result of original research work done by me. I also declare that no material contained in the thesis has been published earlier in any manner. Place: (D. RAVINDRA BABU) I. D. No. BEM Date:

4 CERTIFICATE Mr. D. RAVINDRA BABU has satisfactorily prosecuted the course of research and that thesis entitled OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH submitted is the result of original research work and is of sufficiently high standard to warrant its presentation to the examination. I also certify that neither the thesis nor its part thereof has been previously submitted by him for a degree of any University. Date: Chairperson

5 CERTIFICATE This is to certify that the thesis entitled OPTIMIZATION OF PROCESS VARIABLE FOR PRODUCTION OF JAGGERY FROM INFLORESCENCE SAP OF PALMYRAH submitted in partial fulfilment of the requirements for the degree of Master of Technology in Agricultural Engineering of the Acharya N. G. Ranga Agricultural University, Hyderabad is a record of the bonafide original research work carried out by Mr. D. RAVINDRA BABU under our guidance and supervision. No part of the thesis has been submitted by the student for any other degree or diploma. The published part and all assistance received during the course of the investigations have been duly acknowledged by the author of the thesis. Thesis approved by the Student Advisory Committee Chairperson Er. M. Madhava Assistant Professor Dept. of Agricultural Process & Food Engineering, CAE, Bapatla. Member Er. P. C. Vengaiah Scientist (Food Sci. & Tech.) HRS, Pandirimamidi. Member Er. B. Hari Babu Assistant Professor, Dept. of Farm Machinery & Power CAE, Bapatla. Date of final viva-voce:

6 ACKNOWLEDGEMENTS Accomplishment of this thesis is the result of blessings of Almighty, benediction of my teachers, love of my parents and cooperation of my friends. I am express my sincere gratitude, indebtness to Er. M. Madhava, Assistant Professor & Head, Department of Agricultural Structures, College of Agricultural Engineering, Bapatla for inspiring guidance and valuable suggestions. I am feel elated to express my deep sense of gratitude and affectionate guidance, unending benevolence and constant encouragement given by Er. P. C. Vengaiah, Scientist (Food Sci. & Tech.), Horticultural Research Station, Pandirimamidi. I am sincerely acknowledge valuable suggestions received from Er. B. Hari Babu, Assistant professor & Head, Department of Agro-energy, College of Agricultural Engineering, Bapatla. I am express my thanks to Dr. D. Bhaskara Rao, Associate Dean, College of Agricultural Engineering, Bapatla for encouragement and valuable suggestions for research work. I am express my heartfelt gratitude to Dr. Sivala Kumar, Professor and University Head, Department of Agricultural Process and Food Engineering for valuable suggestions and moral support during the course of the project. I am extend my profound gratitude to Dr. L. Edukondalu, Assistant Professor for constant encouragement and valuable suggestions. I am extremely thankful to Er. K. V. S. Rami Reddy, Assistant Professor and Head, Department of Farm machinery and Power and Er. A. Sambaiah, Assistant Professor and Head, Department of Soil and water engineering for their encouragement and support. I am very much thankful to Teaching Associates Sri. V. Ramanjaneyulu, Er. Ch. Murali Krishna, Er. A. Rama Rao, Er. D. Sai Gangadhara Rao, and Er. B. Raj Kiran for their help during the study period.

7 I am extremely thankful to Sri. G. N. Murthy, Senior Scientist and Head, Sri. A.S.R. Anjaneyulu, A.E.O and attenders A. Pattabhiramaiah and P. Bullidora at Horticultural Research Station, Pandirimamidi. I am extremely thankful to Sri. D. Sudhakara Rao, Assistant Professor and Head, Department of Bio-chemistry, Agricultural College, Bapatla. I am greatly beholden of vocabulary and owe a deep sense of honor to my beloved parents Sri. D. V. Ramanaiah and Smt. D. V. Seshu Kumari for their love and dedicated efforts in shaping of my career. It s time to surface out my affectionate regards to my brother D.V. Bhanu Prakash for his constant cooperation throughout my study. I am express my sincere thanks to classmates Ms. Sk. Haneefa Begum, Mr. G. Samrat, Mr. K. Srinivasa Rao, Mr. R. Jaya Prakash, Mr. D. Anand Babu and my beloved juniors for their cooperation. I am extremely thankful to Sri. D.V. Satyanarayana, Jr. Library Assistant, College of Agricultural Engineering, Bapatla for providing all the necessary books and journals for literature for the present research work. I am also thankful to computer laboratory attender Sri Gurunath and Sk. Hafeez Khan, lab technician, process engineering laboratory and all Non-teaching staff for their necessary help during the course of preparation of this report. I am express my sincere thanks to university authorities for encouragement and providing stipend. Place: Bapatla Date: (D. RAVINDRA BABU)

8 LIST OF CONTENTS Chapter No. Title Page No. List of Tables List of Figures List of Plates List of Appendices i ii iii iv I INTRODUCTION 1 II REVIEW OF LITERATURE 2.1 Palm Types 2.2 Fresh Palmyra Sap Collection 2.3 Preparation of Palmyra-palm Jaggery 2.4 Application of Response Surface Methodology III MATERIAL AND METHODS 3.1 Raw Material 3.2 Collection and Primary Processing of Neera Neera tapping Pre-treatment of neera Measurement of ph Determination of total soluble solids in neera 3.3 Experimental Design CCRD for optimization of process parameters 3.4 Palmyra palm Solid Jaggery Preparation 3.5 Palmyra palm Liquid Jaggery Preparation 3.6 Determination of Nutritional Composition Determination of total sugar Materials Procedure Calculation Determination of ash content Determination of moisture content Determination of protein content Materials Procedure Calculation Determination of fat 3.7 Sensory Evaluation of Solid and Liquid Jaggery Samples

9 IV RESULTS AND DISCUSSION 4.1 Analysis of Fresh Neera 4.2 Optimization of Operational Parameters Total sugar Ash Moisture content Optimization of process variables 4.3 Proximate Composition 4.4 Sensory Evaluation of Quality Parameter of Solid Jaggery Sensory evaluation of solid and liquid jaggery samples using 9-point hedonic scale V SUMMARY AND CONCLUSIONS LITERATURE CITED APPENDICES

10 LIST OF TABLES Table No. Title Page No. 3.1 Coded values and corresponding real values used in experimentation 3.2 Design of experiment for jaggery preparation with three independent variables in CCRD 3.3 Details of solid jaggery samples used for sensory evaluation Analysis of fresh neera samples Effect of process parameters on total sugars (S), ash (A) and moisture content (M) of jaggery 4.3 Regression coefficients of the second order polynomial model for total sugars, ash and moisture content (coded values) 4.4 Analysis of variance showing the lime, time and temperature on total sugars 4.5 Analysis of variance showing the lime, time and temperature on ash 4.6 Analysis of variance showing the lime, time and temperature on moisture content 4.7 Optimization criteria for different operational variables and responses Proximate composition of solid and liquid jaggery Sensory evaluation of solid jaggery samples Sensory evaluation of liquid jaggery samples 37 i

11 LIST OF FIGURES Figure No. Title Page No. 3.1 Process flow diagram for the production of liquid and solid jaggery with mass balance (a) 4.1(b) 4.1(c) 4.2(a) 4.2(b) 4.2(c) 4.3(a) 4.3(b) 4.3(c) Response surface plot showing the effect of lime and temperature on total sugars at constant time 150 min Response surface plot showing the effect of lime and time on total sugars at constant temperature 117 C Response surface plot showing the effect of temperature and time on total sugars at constant lime 1.5 per cent Response surface plot showing the effect of lime and temperature on ash content at constant time 150 min Response surface plot showing the effect of lime and time on ash content at constant temperature 117 C Response surface plot showing the effect of temperature and time on ash content at constant lime 1.5 per cent Response surface plot showing the effect of lime and temperature on moisture content at constant time 150 min Response surface plot showing the effect of lime and time on moisture content at constant temperature 117 C Response surface plot showing the effect of temperature and time on moisture content at constant lime 1.5 per cent ii

12 LIST OF PLATES Plate No. Title Page No. 3.1 Tapping operation of palmyra sap Fresh palm juice collections Palm juice collected in to earthen pots Measurement of sap temperature End point detection Mould used in the preparation of solid jaggery Palmyra palm jaggery samples 37 iii

13 LIST OF APPENDICES Appendix Title Page No. A Jaggery and confectionery items exports from India in B Experimental data of total sugars, ash and moisture content for treatment combinations. 45 C Nutritional properties of palmyra palm jaggery at different strike temperatures. 46 D Sensory evaluation card 47 iv

14 LIST OF SYMBOLS AND ABBREVIATIONS A : Ash ANOVA : Analysis of Variance APR : Adequate Precision Ratio b.p : Boiling Point CCRD : Central Composite Rotatable Design cm 3 : Cubic centimetre CV : Coefficient of Variation C : Degree Celsius Df : Degrees of freedom et al. : and others g : Gram in : Inches kcal : Kilo Calories L : litre M : Moisture content (d.b) mg : Milligrams min : Minute ml : Millilitre Mt : Million tonne nm : Nanometre ns : Non-significant % : Percent p : Probability / : Per RSM : Response Surface Methodology R 2 : Coefficient of Determination S : Total Sugars TSS : Total Soluble Solids g/cm 3 : Gram per cubic centimetre v

15 ABSTRACT Title of thesis : Optimization of Process Variable for Production of Jaggery from Inflorescence Sap of Palmyrah Author : D. Ravindra Babu Chairman : Er. M. Madhava Submitted For Award of : Master of Technology Faculty : Agricultural Engineering & Technology Major Field : Processing and Food Engineering University : Acharya N. G. Ranga Agricultural University Year of Submission : 2012 In India, the Palmyra palm (Borassus flabellifer L.) is found in dry regions along the coastal areas of peninsula and in West Bengal and Bihar. Present days, people worldwide are becoming health conscious. Diabetics and obesity are two major health problems in India as well as in world due to consumption of high calorie sweeteners. Palmyrah palm jaggery has been used as sweetening agent and medicine. Palmyra jaggery industry has problems in storage of neera, determination of end point of high total soluble solids concentration; quantity of lime to be used for neera unfermentation, temperature and time to be heated for jaggery preparation. Response surface methodology (RSM) gives best combination of process variables in the preparation of palmyra jaggery, fitting of mathematical models, statistical techniques and analysis of responses. Central composite rotatable design was used with three independent variables viz., quantity of lime, heating time and temperature for the operational parameters optimization. For experimentation five data levels (coded and real values) are selected based on preliminary trails for each independent variable. Palmyra palm jaggery samples were prepared according to fifteen experimental combinations and their nutritional properties such as total sugars, ash and moisture content were determined. Mathematical models, anova tables and response surface plots of three independent variables on nutritional properties were determined. Best suited combination of independent variables is determined by optimization criteria for all operational variables and responses. Nutritional properties of both liquid and solid jaggery were determined according to proximate analysis using standard methods. The consumer acceptance and sensory evaluation of both liquid and solid jaggery were determined using nine point hedonic scale. Response surface plot of lime and temperature on total sugars at constant time 150 min indicated that the lime effect on total sugars was less. When temperature increases vi

16 the total sugars increases with increase in lime. The response surface plot of lime and time on total sugar at constant temperature 117 C indicated that the total sugar content decreased from 90.4 per cent to 90 per cent when the lime percentage increased from 0.9 per cent to 2.1 per cent at the constant time of 126 min. The response surface plot of temperature and time on total sugars at constant lime 1.5 per cent indicated that the total sugars slightly increased from 90 per cent to 90.4 per cent when the temperature rose from 113 C to 121 C at 126 min time. The proximate compositions of both solid and liquid jaggery samples were determined. Solid jaggery has moisture content- 8.5 per cent, fat per cent, protein per cent, ash- 4.5 per cent and carbohydrates per cent. Liquid jaggery has moisture content- 32 per cent, fat- 0.1 per cent, protein- 0.4 per cent, ash- 1 per cent and carbohydrates- 70 per cent. The sensory evaluation of both solid and liquid jaggery samples were conducted according to material and method section. Solid jaggery samples S 4, S 5, S 7, and S 9 had higher scores for colour; S 1, S 4, S 5, S 6 and S 7 for taste; samples S 1, S 4, S 5, S 7 and S 9 for flavour; and samples S 1, S 4, S 5, and S 7 for texture / appearance. Solid jaggery sample S 4 having a combination of 2.1 per cent lime, 111 C temperature and 126 min time showed high score in sensory evaluation. The sensory evaluation for liquid jaggery sample L 3 ranks higher for colour, L 5 ranks higher for taste and flavour, L 3 ranks higher for mouth feel. Key Words: Palmyra palm jaggery, process optimization for palm, neera vii

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26 Chapter I INTRODUCTION Sugar yielding palms are known to mankind for their economic potentialities. Palm belt in the world roughly extends from 44 degree south latitude to 45 degree north latitude and widely encompasses the tropical countries like Congo, Sri Lanka, India, Bangladesh, Indonesia, Malaysia and abundant in India. The palm, botanically known as palmate, has been termed the princes of the vegetable kingdom. In India, there are four varieties of sugar-yielding palms such as date, coconut, palmyrah and sago. They give food, shelter, timber, fuel, building materials, sticks, fibre, paper starch, sugar, oil wax, wine, tannin, dyeing materials, resin and a host of minor products. Palm trees thrive on non-agriculture lands, on the banks of streams, rivers and canals, on undulating hill slopes and sandy soil which are normally unfit for cultivation (Anonymous, 2004). Palmyra palm (Borassus flabellifer L.) belongs to the family Palmae. Palmyra is an important multipurpose tree of great utility. In India, the palm is found in dry regions along the coastal areas of peninsula and in West Bengal and Bihar. These palms grow abundantly in sandy plains just above the sea level having annual rainfall of 620 to 650 mm (Ghosh et al., 1998). Tamil Nadu ranks first in India, in the population of palmyra palms having 51.9 million trees (Sankaralingam et al., 2010). There are two kinds of the palmyrah, the male and the female. Both trees are used for tapping neera. Palmyra is a very important palm and playing an important role in the day-to-day life of poor and land less farmers. Among 103 million palm trees in India, 30 per cent of trees are in Andhra Pradesh. Due to its multifarious uses, the palm is equated to the Kalpa Vriksha in the mythology (Anonymous, 2004). Palmyra is one of the most important and an alternate source for the production of jaggery or gur among wild date palm (Phoenix sylvestris L.), sago palm (Caryota urens L.) and coconut palm (Cocos nucifera L.) to the traditional sugarcane crop (Saccharum officinarum). Sugarcane jaggery is made from juice obtained by crushing the sugarcane where as in palm trees (palmyra, date, sago and coconut) jaggery is made from fresh and sweet sap (neera). The sap or juice collected from these trees contains 1

27 around per cent total sugar; mainly composed of sucrose, less amount of reducing sugar, and other minerals and vitamins (Rao et al., 2009). The palmyra palm throws out spathes during the flowering season. Fresh and sweet sap (neera) is the chief product of the palmyra obtained by exudation and collection (tapping) the tip of the inflorescence and tapping is done in the early hours of day before sun rise. It is clear, almost transparent, sweet, pleasant smelling and refreshing and popular drink on account of its highly nutritive value, delicious taste and agreeable flavour. The fresh sap is reportedly a good source of vitamin B (Ghosh et al., 1998). It contains all the constituents of a cool and healthy drink with food and mineral value. It builds the body; keeps the human system cool and improves digestion. It can be consumed in fairly large quantity without any harm to the system and it is good tonic to the asthmatic, anaemic, leprosy patients, cures digestive problems. Gur, syrup, rab, sugar, candy confectionery, ice creams and various sweets are produced from neera. Fresh neera, as it trickles from the tree, is easily susceptible to fermentation at ordinary temperature, unless it is quickly treated with some preservative (Anonymous, 2006). India produces about 6 Mt of jaggery annually, which accounts for 70 per cent of the total production in the world; per cent of the total jaggery is from sugarcane and the remaining 30 per cent is from palms. Jaggery produced from both sugarcane and palms have their own characteristic taste and aroma and their production is seasonal. The quality of the prepared jaggery, such as aroma, texture, colour and taste, is largely dependent on monitoring and controlling of various physical and chemical changes occurring during concentration, particularly when the process approaches the end point (high total soluble solid concentration (Rao et al., 2009). Jaggery or Gur means the product obtained by boiling or processing juice extracted from palmyra palm (Borassus akeassii of family Arecaceae). The quality of jaggery can be improved by precipitating lime with carbon dioxide gas or citric acid or unripe tamarind fruits, before boiling the juice. The yield of palm jaggery obviously depends on sugar content of the juice and the efficiency of extraction process. Palmyra palm jaggery should meet the analytical standards according to Prevention of Food Adulteration rules, They are total sugars (invert sugars) shall not be less than 90 per cent, total ash not more than 6 per cent and moisture content shall not be more than 10 per cent. 2

28 Liquid jaggery is an intermediate product obtained during jaggery making. It is one of the important sweetening agents known from ancient times. It is collected in semi-liquid form, from the boiling juice at a particular temperature and could be preserved for a year or more. Liquid jaggery or kaakavi contains water, sugars and nonsugars. The sugars are in the form of sucrose, glucose and fructose. The quality and colour of liquid jaggery are governed by the amount of glucose-fructose content of the final product. The juice after sedimentation and removal of suspended impurities is transferred in to the boiling pan on a furnace, preferably of Padegaon or Kolhapur type pans. About fifty g of lime is added to bring the ph of juice to 5.8 to 6 (Singh and Solomon, 1995). Agmark standards clearly indicated the minimum requirements of jaggery that it should be well dried of firm consistency non sticky or plastic; having characteristic taste and flavour; clean and free from insect infestations, live insect, dead insects, insect fragments, mould or mites, larvae, rodent hair and excreta; free from fermented and musty odour; free from dirt or soil; free from natural or synthetic colours, artificial sweetening agents; free from any fungal or bacterial contamination; free from deleterious substances injurious to health; free from bleaching agents; free from added starch and also jaggery shall comply with the residual level of poisonous metals, crop contaminants, naturally occurring toxic substances, insecticides and pesticide residues and other food safety requirements as laid down under the provisions of Prevention of Food Adulteration rules, 1955 for domestic purpose and it shall comply with the residual levels of heavy metals, pesticides residue and any other food safety requirements as prescribed under codex alimenterius commission or importing countries requirement for export purpose and it shall be sweet to the taste and free from any objectionable flavour (Agmark, 2008). Food products like solid and liquid jaggery from palmyrah is not commercialised as the process for the preparation of those foods are not standardised and traditional practices exist. Even though the palmyra is an economically important palm it has not received proper attention from the researchers probably on account of the fact that it is very slow growing palm found mostly in the wild state. As production of the most economic products like neera, fruit and nungu are seasonal; there is a need to further concentrate on the development of post-harvest techniques so as to preserve the produce in its natural form for longer period (Vengaiah et al., 2011). 3

29 Price of palm jaggery is determined by quality, especially the flavour. Since the availability of palm jaggery is seasonal and demand is usually more than its production, its price is comparatively much higher than sugarcane gur. Palm jaggery industry is an interesting and rewarding activity having problems in processing, preservation and storage. On a world scale, the palm jaggery industry rural in nature and preparation process was controlled by the experienced operators but having less scientific knowledge, which leads to lack of process standardisation for both liquid and solid jaggery (Guerra and Mujica, 2009). Palmyra jaggery industry facing the problems in quantifying the lime to be used to prevent the fermentation neera after tapping and heating temperature and heating time of neera for jaggery preparation to maintain proper quality, yield and nutritional properties. Nutritional quality of liquid and solid jaggery products are not given much importance though they are used in the preparation of ayurvedic/traditional medicines, and for reduce the chances of lung cancer, diabetes and obesity. For better export market potential and supporting price, optimizing the processing parameters plays an important role. In present study, the process was to be developed for the production of palmyra solid and liquid jaggery with the following objectives: 1. To optimize process parameters such as lime quantity, heating time and temperature for solid and liquid jaggery for better quality, maximise yield and nutrition. 2. To determine the nutritional qualities through proximate analysis of solid and liquid jaggery. 3. To determine the consumer acceptance and sensory evaluation of solid and liquid jaggery. 4

30 Chapter II REVIEW OF LITERATURE This chapter gives information on types of sugar yielding palms, fresh palmyra sap, nutritive value of palmyra palm jaggery and various palmyra palm jaggery preparation procedures available in literature. Application of response surface methodology for optimization has been reviewed. 2.1 Palm Types Anonymous (2004) reported that palm jaggery was a sweet food obtained by boiling the unfermented juice of sugar yielding palms like palmyra, date, coconut and sago. These palms are the potential sources for supplying sweetening agents like jaggery, sugar and a host of subsidiary products for our day to day use. The yield of palm jaggery obviously depends on sugar content of the sap (Neera) and the efficiency of extraction process. Palmyrah palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Wild date palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Coconut palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Sugar palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Fish tail palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Nipa palm has l average daily yield/tree, l average yield per season/tree and per cent sucrose content in juice/sap. Basic idea of palmyra palm neera yield was known from the above information was used in the neera collection process and in experimentation. 2.2 Fresh Palmyra Sap Collection Sankaralingam et al. (2010) given the neera collection process includes that neera is brought down from the top of the tree in lime treated earthen pots and filtered through a fine mesh cloth, so that only neat, clean neera is obtained. Generally, in India earthen 5

31 pots are being used for neera collection in all states. The earthen pots should be well cleaned and dried before usage. Father of the Nation Mahatma Gandhi stated that Neera can be converted in to jaggery, sweet as honey itself. This jaggery is superior to cane jaggery. Cane jaggery is sweet, but palm jaggery is sweet and delicious; it can be produced worth crores of rupees. Palm jaggery gives mineral salts too. Where there are palm trees, this jaggery can be easily produced. This is the way of banishing poverty from our land. This also is an antidote to poverty. Anonymous (2004) reported that tapping was done both in the morning and evening by tappers. The quantity of palmyra sweet sap (neera) obtained varies from season to season and inflorescence of both male and female trees. Sap extraction seasons for male and female are November to January and February to April respectively. The change in sugar content of neera (at 37 C) analysed due to storage of neera with reference to the time factor. For 0 h, the minimum sugar content was g/100 cm 3 and the maximum sugar content was 13.2 g/cm 3. For 24 h, the minimum sugar content was 4.41 g/100 cm 3 and the maximum sugar content was 9.3 g/cm 3. For 48 h, the minimum sugar content was 1.12 g/100 cm 3 and the maximum sugar content was 6.08 g/cm 3. For 72 h, the minimum sugar content was 0.91 g/100 cm 3 and the maximum sugar content was 3.06 g/cm 3. Nutrients available in 250 ml of neera was ph 7.2, total sugar 28.8 g, calcium 35.5 mg, iron 5.5 mg, phosphorous 32.4 mg, thiamine 82.3 mg, riboflavin 44.4 mg, ascorbic acid 12.2 mg, nicotinic acid mg, protein 47.7 mg and energy kcal. Neera should be collected with lime treated earthen pots to prevent fermentation and it has many nutritional properties. Palmyra jaggery was prepared from neera has large export potential and has many nutritional properties. 2.3 Preparation of Palmyra-palm Jaggery Sankaralingam et al. (2010) stated that neera was collected in lime treated earthen pots and filtered through a cloth to remove the debris or dust. Clarification (Deliming) process was done at 40 C to reduce ph to 7.5 using either phosphoric acid or triple super phosphate solution or citric acid. Clarified juice gives jaggery of light colour, crystalline in texture, hard, less hygroscopic and hygienic. Juice was boiled to 110 C in a pan made of galvanized iron (GI) or alloy metal of 20 to 24 gauge thicknesses. A pinch of coconut kernel or caster seed powder is added to prevent over boiling. Neera gets transformed into a viscous fluid at 110⁰C. The liquid jaggery stage 6

32 attained between C and solid jaggery attained at 120 C. The fluid is stirred continuously for half an hour to avoid charring at the bottom of the vessel. Correct strike temperature is judged by putting a small quantity of the thickened mass in water and rolling into ball shape. If ball form as a hard one and rebounds when it strikes on a hard surface, which indicates the end point of high total soluble solids in the thick viscous mass. Then it is moulded into moulds for desire shape. The strike temperature can also be controlled with the help of thermometer. In south India, coconut shells are generally used as moulds. Wooden and iron moulds are used in other parts of India. In order to facilitate easy removal of the blocks from the moulds, the moulds are either moistened with water or be smeared with fresh sweet oil before putting the thick mass into them. After allowing the thick mass to set for some time, the jaggery is removed from the moulds and packed. Rao et al. (2009) stated that 55 l of juice (sap) for the preparation of palmyra palm jaggery having initial total soluble solid content of 16 Brix and it was first filtered through a fine muslin cloth and boiling was carried out in an open shallow aluminium pan. A mild bleaching agent (Hydro s - sodium hydrosulphite) at the rate of 5 g/50 l juice was added intermittently during boiling for clarification of juice. Boiling of juice continued in a regulated manner for more than 2 h till the syrup attained total soluble solids around 81 Brix. At that time, temperature rise to about 120 C. Anonymous, (2006) stated that the quality of palmyra palm jaggery was always hard, crystalline and golden- coloured. One kg of jaggery can be obtained from 8 litres of neera. Ghosh et al. (1998) stated that palmyra palm jaggery was more nutritive than sugarcane jaggery. Palm jaggery contains 1.04 per cent protein, 0.19 per cent fat, per cent sucrose, 1.66 per cent glucose, 3.15 per cent total minerals, per cent calcium, per cent phosphorus, also mg iron per 100 g and mg of copper per 100 g. Production of liquid and solid jaggery includes many difficulties in neera collection, lime pre treatment, deliming and strike point determination. Details of deliming, strike points for both liquid and solid jaggery, end point detection and moulding are used in the present research. Palmyra jaggery industry requires experienced skilful operators to minimise loss of jaggery. 7

33 2.4 Application of Response Surface Methodology for Optimization Chakraborty et al. (2011) applied response surface methodology (RSM) for preparing millet enriched biscuits of overall acceptability which involves design of experiments, selection of levels of variables in experimental runs, fitting mathematical models and finally optimizing the responses was employed in the study. A central composite rotatable design (CCRD) was used to design the experiments comprising three independent processing parameters. Karunanithy and Muthukumarappan (2011) conducted several extrusion studies using Response Surface Methodology (RSM) for optimising extrusion parameters, blends, torque, and specific mechanical energy. RSM is an effective optimisation tool wherein many factors and their interactions affecting the response can be identified using relatively few experiments. Sansonetti et al. (2010) performed optimizing the process leading to bio-ethanol formation using the effects of four factors, i.e. temperature, ph, agitation rate and initial lactose concentration. The central composite design (CCD) was performed to evaluate both single and interaction effects of both first and second order. Mangaraj and Singh, (2009) examined optimization of machine parameters using response surface methodology (RSM) for milling study of pigeon pea. The independent milling parameters for dhal mill viz., roller speed, emery grit size and feed rates were optimized for pigeon pea dehulling using RSM. The optimal values of roller peripheral speed, emery grit size and feed rate are 9.6 ms -1, 1 mm and 111 kg h -1 respectively. The dhal recovery and milling efficiency at optimized independent parameters were 75 per cent and 80 per cent respectively. Goyal et al. (2008) optimised dehulling efficiency and loss using response surface methodology for pigeon pea under the effects of dehulling time, moisture content and the use of mustard oil as a pre-milling treatment agent were studied. A quadratic model satisfactorily described the dehulling efficiency with high value for the coefficient of determination R 2 (0.95) values. It predicted a maximum dehulling efficiency of 83.2 per cent at 10.1 per cent moisture content, 12.3 s dehulling time and 0.3 per cent mustard oil treatment. Moisture content and dehulling time affected dehulling loss significantly whereas the effect of mustard oil treatment was non- 8

34 significant. A dehulling loss of 2.5 per cent was predicted at optimum conditions. The results of the predicted optimum conditions were validated experimentally. Dehulling efficiency and loss at optimum conditions were observed to be 82.4±0.8 per cent and 3.1±0.4 per cent, respectively. Montgomery (2001) indicated that response surface methodology (RSM) is a collection of mathematical model and statistical techniques that are useful for the modelling and analysis of problems in which a response of interest is influenced by several variables and the objective is to optimize this response. Central composite rotatable design was used with three independent variables viz., quantity of lime, heating time and temperature for the operational parameters optimization. For experimentation five data levels (coded and real values) are selected based on preliminary trails for each independent variable. Data levels, names of independent variables and names of dependent variables are entered into the design expert software for complete experimental design. Twenty experimental combinations having three independent variables are listed, which includes six equal combinations. After, jaggery samples were prepared according to the experimental design are subjected to determination of nutritional properties such as total sugars, ash and moisture content. The experimentally observed values of nutritional properties are entered into design expert software. By proceeding further, software automatically develops mathematical model, anova tables and response surface plots of three independent variables on nutritional properties. Best suited combination of independent variables is determined by using optimization criteria for all operational variables and responses. 9

35 Chapter III MATERIAL AND METHODS This chapter deals with the description of raw materials, chemicals, experimental design and methodology. The project work was divided into three phases. Phase I devoted to process optimization of solid and liquid jaggery, phase II devoted to nutritional analysis of solid and liquid jaggery and phase III devoted to sensory evaluation of solid and liquid jaggery. 3.1 Raw Material Fresh neera (palm juice) was procured from experimental plot of 18 palmyra trees at Horticultural Research Station, Pandirimamidi; Andhra Pradesh was used for preparation of liquid and solid jaggery. Inflorescence saps (Neera) of both male and female were used. Instruments used for the preparation of liquid and solid jaggery included: 1. Digital thermometer (Multi Thermometer, range -50 to +150 C, accuracy ±1 C, resolution 0.1 C): Temperature was measured by dipping the probe into sugar syrup and instant temperature was displayed. It works on principle using digital volt meter and thermocouple. 2. Galvanized Iron pan (152.4 mm mm): Semi spherical base Galvanized Iron pan was used in the preparation of liquid and solid jaggery for quick heating. 3.2 Collection and Primary Processing of Neera Neera tapping Carefully crushed and ruptured the tender tissues of the floral components by gently hammering and pounding the spathe (Plate 3.1). This process was repeated over a period of six days. The spathe was then gently and gradually bents so that the earthen pot was placed on its collection (Plate 3.2). Point on the sixth day the apical tissue was parred off with tapping knife. After, slicing was done once in the morning and second time in the afternoon, the operations direct the sap to the wounded region and at the same time allowing the flowering branches to produce a flow of the juice. 10

36 Fresh and sweet sap (neera) was collected in earthen pots (Plate ( 3.3) for the preparation of jaggery from November 2011 to April About 18 trees both male and female trees were tapped in the early morning during 6 to 7 AM and daily record was maintained on the yield of neera.. Proper training and demonstration were given to the tappers on maintaining hygiene and sanitation which directly affects affect the quality of jaggery. Plate 3.1. Tapping operation of palmyra almyra sap Plate 3.2. Fresh palm juice collections Plate 3.3. Palm juice collected in to earthen pots 11

37 3.2.2 Pre-treatment of neera As the time progress from tapping, fresh and sweet sap (neera) susceptible to fermentation, leads to reduction in total soluble solids (sugar) concentration ( Brix). Fermented sap (toddy) white in colour and gives bad quality jaggery i.e. which are black in colour, sour in taste and sticky in touch. Especially in solid jaggery, loss of crystallinity takes place. So, for getting good quality jaggery, sap should be treated with lime to prevent fermentation. Measured quantity of lime was poured into earthen pot and spread the lime uniformly inside the earthen pot with small fibre brush Measurement of ph Acidity (ph) of sap was measured using digital ph tester (Hanna Instruments, HI p H ep ph tester, accuracy - ± 0.1) having oxidation reduction potential (ORP) measuring type (Ranganna, 1994) Determination of total soluble solids in neera Two hand refractometers (Wiswo instruments, Mumbai) having ranges 0-50, Brix were used to determine total soluble solids concentration (Ranganna, 1994). 3.3 Experimental Design To reduce a large number of experiments, with three independent variables, a Central composite rotatable design (CCRD) and response surface methodology (RSM) has been successfully applied to optimize operational parameters. CCRD experiment was conducted with three process variables keeping optimized values of process parameters. For each experiment 10 litre neera sample was used. For optimization of independent operational parameters (lime (per cent), time (min), and temperature ( C)), fifteen experiments were carried out according to CCRD and their combined effects were studied. For each experiment 10 litres of neera was used. The neera was filtered using standard filtration white muslin cloth and de-limed with food grade citric acid. Experiments were conducted immediately after neera collection. A central composite rotatable design was used to show interactions of per cent lime over temperature and time on the responses of total sugars, ash and moisture content were estimated. 12

38 3.3.1 CCRD for optimization of process parameters A CCRD experiment was made with three independent variables viz., quantity of lime (X 1 ), heating time (X 2 ) and temperature (X 3 ). In the design, the coded values of independent variables viz., x 1, x 2 and x 3 were converted into their real form as X 1, X 2, and X 3 respectively by using equations 3.1 to 3.4. xi = X i X X D m (Here i =1, 2 and 3) (3.1) X D = X max a m X m (3.2) X m = a = m X + max X min k 2 (3.3) (3.4) Where, X max = maximum value of independent variable, X min = minimum value of independent variable, a m = extreme coded value, k = number of independent variables considered for optimization and X D = interval difference of the independent variable. Non linear second order regression equations were developed of the form equation (3.5). Y = a ai xi i= aii xi i= aij xi x j i= 1 j = i+ 1 (3.5) The goodness of fit of the developed nonlinear equations was tested by F value for lack of fit (F lof ). The value of F lof was calculated using equation 3.6 F lof N 2 nc 2 ( Y ai Y ci) ( Y ai Y a) i= 1 i= 1 = N no of coefficients in regression equation n c + 1 (3.6) Independent process variables, coded values and their real values are given in Table 3.1. The experiments were conducted in random order. In this study, the optimization was carried out using Design Expert software (Design Expert, 2012), which gave optimum values based on predicted conditions given in Table 3.1. Table 3.2 gives complete experimentation in coded and real values given by Design Expert software and third experiment is a centre point combination. 13

39 Table 3.1. Coded values and corresponding real values used in experimentation Independent variable Lime, % Temperature, C Time, min Coded levels Actual levels -α (-1.682) Data levels α (+1.682) Table 3.2. Design of experiment for jaggery preparation with three independent variables in CCRD Expt. No. Lime, % (X 1 ) Temperature, C (X 2 ) Time, min (X 3 ) (0) 124 (+1.682) 150 (0) ( 1) 121 (+1) 174 (+1) (0) 117 (0) 150 (0) (+1) 113 ( 1) 174 (+1) (-1.682) 117 (0) 150 (0) (0) 117 (0) 190 (1.682) (-1) 111 (-1) 126 (-1) (+1) 121 (+1) 174 (+1) (+1) 121 (+1) 126 ( 1) (+1) 111 (-1) 126 (-1) (-1) 121 (+1) 126 (-1) ( 1) 111 ( 1) 174 (+1) (0) 117 (0) 110 (-1.682) (0) 110 (-1.682) 150 (0) (1.682) 117 (0) 150 (0) 3.4 Palmyra palm Solid Jaggery Preparation Initially, 10 litres of lime treated neera was filtered through a fine muslin cloth to remove the debris or dust. The minimum requirements of neera for jaggery preparation are ph: between 7-8 and total soluble solids (TSS) 10 Brix. However, high ph value indicates excess lime deposits in sap. 14

40 Process flow diagram for the production of liquid and solid jaggery with mass balance was shown in Fig Tapping Samples of fresh sap (Neera) is collected in Ca (OH) 2 (Lime) treated earthen pots at different pre-selected quantities (10 litre) Straining of neera into boiling pot to remove sediments of lime Heating of neera in Round bottom GI Sheet Pan using gas burner Remove froth and foam using perforated ladles While at 40 C heated neera is clarified using phosphoric acid or super phosphate or citric acid for deliming to neutrality (ph-7) stirring with ladle (9.6 litres) 55 min taken to reach neera temperature at 100 C At 100 C, all water will be evaporated (5.5 litre) 108 C, liquid jaggery stage Liquid Jaggery (4.0 kg) Flame is reduced gradually according to the thickness of the sugar syrup Judging the correct strike temperature C Allowed to solidify in the moulds, solid jaggery stage (1.6 kg) Palm Gur (1.4 kg) Figure 3.1. Process flow diagram for the production of liquid and solid jaggery with mass balance 15

41 Heating was carried out in galvanized iron (GI) pan. In order to neutralize i.e. to bring ph between 7 to 8, food grade citric acid was added at 40 C of sap s temperature (Plate 3.4). Plate 3.4. Measurement of sap temperature The hardening of the sugar syrup in the cold water indicates indicat the right stage of conversion of neera in to jaggery (Plate 3.5). Plate 3.5. End point detection The jaggery is poured into oill smeared wooden mould ( cm) cm of square shape (Plate 3.6).. After solidification square shaped jaggery is removed from the mould and stored at room temperature. 16

42 Plate Mould used in the preparation of solid jaggery 3.5 Palmyra palm Liquid L Jaggery Preparation Liquid jaggery is an intermediate product obtained during solid jaggery preparation. The process of liquid jaggery preparation was quite similar to that of solid jaggery but differs at striking point. Strike point for liquid jaggery is 108 C. C. Five liquid jaggery samples were collected in labelled glass bottles in between 106 C C and 110 C Determination of Nutritional Composition Nutritional properties namely, total sugars, ash, moisture content, content fat and protein contents required for the present investigation were determined as follows: Determination of total sugars Estimation of total sugar in the sample was carried out by Anthrone method (AOAC, 2005) Materials (i). 2.5 N-Hcl (ii). Anthrone reagent: Dissolve 200 mg anthrone in 100 ml water. (iii). Working standardstandard 10 ml of stock diluted to 100 ml with distilled water. Store refrigerated after adding a few drops of toluene Procedure (i). Weigh 100 mg of the sample into int a boiling tube. (ii). Hydrolyse by keeping it in a boiling water bath for three hours with 5 ml of 2.5 NHcl and cool ol to room temperature. (iii). Neutralise it with solid sodium carbonate until the effervescence ceases. 17

43 (iv). Make up the volume to 100 ml and centrifuge. (v). Collect the supernatant and take 0.5 and 1 ml aliquots for analysis. (vi). Prepare the standard by taking 0, 0.2, 0.4, 0.6, 0.8 and 1 ml of the working standard. 0 serves as blank. (vii). Make up the volume to 1 ml in all the tubes including the sample tubes by adding distilled water. (viii). Then add 4 ml of anthrone reagent. (ix). Heat for eight minutes in boiling water bath. (x). Cool rapidly and read the green colour at 630 nm. (xi). Draw a standard graph by plotting concentration of the standard on the x axis versus absorbance on the y-axis. (xii). From the graph calculate the amount of carbohydrate present in the sample tube Calculation Amount of carbohydrate present in 100 mg of the sample = ( ) ( ) 100 (. ) ( ) Determination of ash content Ash content was determined according to AOAC, Ignite 5 g of sample in a tarred dish on a low flame until the mass is thoroughly charred. Heat in a muffle furnace at 550 C until an almost white ash is obtained. Cool in desiccators, moisten the ash with a few drops of water, dry on a water bath, again heat in a muffle furnace, cool and weight. The difference in weight gives the ash content. Express the ash content as per cent. ( W1 W2 ) Ash content, % = 100 W Where, W 1 = Weight of sample + Crucible before ashing, g W 2 = Weight of sample + Crucible after ashing, g And W = Weight of sample, g 18

44 3.6.3 Determination of moisture content Moisture content of palmyra palm jaggery samples was determined according to hot air oven method (AOAC, 2005). Samples of each 5 g was accurately weighed into a clean dry petridish and dried in as oven at 105 C for 24 h. After 24 h, dried samples are allowed to cool in desiccators and weighed till constant weights are obtained. Moisture content, % (d.b) = ( W ) 1 W2 Where, W = Weight of petri dish, g W 1 = Weight of petri dish + sample, g W 2 = Weight of petri dish + dried sample, g ( W1 100 W ) Determination of protein content Protein content in palmyra palm jaggery can be estimated by Lowry s method (AOAC, 2005). Hydrolysing the protein and estimating the amino acids alone will give the exact quantification. Lowry s method is sensitive enough to give a moderately constant value and hence largely followed. Protein content of enzyme extracts is usually determined by this method Materials (i). Reagent A: 2 per cent sodium carbonate in 0.1N sodium hydroxide: Firstly, prepare 0.1N sodium hydroxide by weighing 0.4 g NaOH and dissolve in ml of distill water and make up to 100 ml. Dissolve 2 g of Na 2 CO 3 in ml of 0.1N sodium hydroxide and make up to 100 ml. (ii). Reagent B: 0.5 per cent copper sulphate (CuSO 4.5H 2 O) in 1 per cent potassium sodium tartrate: Firstly, weigh 1 g of potassium sodium tartrate and makes it dissolve in to ml of distilled water and finally make in to 100 ml. Similarly dissolve 0.5 g of copper sulphate in 60 ml of 1 per cent potassium sodium tartrate solution and finally make up to 100 ml. (iii). Reagent C: Mix 50 ml of Reagent A and 1 ml of Reagent B prior to use. (iv). Reagent D: Folin - ciocalteau reagent 19

45 (v). Stock standard solution (protein Solution): Weigh accurately and dissolve 100 mg of bovine serum albumin (B.S.A) in 100 ml of distilled water. (vi). Working standard solution: Dilute 10 ml of Stock Solution to 100 ml with distilled water in a standard flask Procedure Weigh 500 mg of the sample and grind well with a pestle and mortar is ml of the buffer. Centrifuge and use the supernatant for protein estimation. (i). Pipette out 0.2, 0.4, 0.6, 0.8 and 1 ml of the working standard into a series of test tubes. (ii). Pipette out 0.1 ml and 0.2 ml of the sample extract in two other test tubes. (iii). Make up the volume to1 ml in all the test tube. A tube with 1ml of water serves as the blank. (iv). Add 5 ml of reagent C to each tube including the blank. Mix well and allow standing for 10 min. (v). Then add 0.5 ml of reagent D, mix well and incubate at room temp in the dark for 30 min. (vi). Blue colour is developed. (vii). Take the reading at 660 nm (viii). Draw a standard graph and calculate the amount of protein in the sample Calculation Express the amount of protein mg/g or 100 g sample Determination of fat Fat was determined by soxhlet method (Ranganna, 1994). 2 g of the sample was accurately weighed into a dry thimble and extracted using petroleum ether (40-60 b.p) as solvent for 2 h. The fat extract was collected in a previously weighted dry flatbottomed flash and separated from the solvent by evaporating over a hot water bath. 20

46 The flask was dried in an oven at C and cooled till constant weight was achieved. Fat content of the samples were expressed as g/100 g of sample. The amount of fat present in given sample (palm jaggery) is Fat, % = ( ),, Sensory Evaluation of Solid and Liquid Jaggery Samples Ten judges were selected based on their good health, interests in sensory evaluation, ability to learn and concentrate. They were mostly the staff, students and non-teaching staff of College of Agricultural Engineering, Bapatla. Judges were familiarized with quality attributes for evaluation like, colour, sweetness, flavour, mouthfeel and texture were asked to score 9 samples (Table 3.3) comfortably choose among nine ratings for each of the quality attributes. The scoring was done according to the pattern of 1. Dislike extremely, 2. Dislike very much, 3. Dislike moderately, 4. Dislike slightly, 5. Neither like nor dislike, 6. Like slightly, 7. Like moderately, 8. Like very much and 9. Like extremely. The score card was also used to record the weight age given by each judge for the quality attribute of solid jaggery in general. The sensory score card used for evaluation of sample qualities in general is given in Appendix C. Similarity values of nine jaggery samples and values of quality attributes of jaggery samples in general were determined. Table 3.3. Details of solid jaggery samples used for sensory evaluation Sample Lime, % Temperature, C Time, min S S S S S S S S S Liquid jaggery samples collected at 106 C (L 1 ), 107 C (L 2 ), 108 C (L 3 ), 109 C (L 4 ) and 110 C (L 5 ) are allowed for sensory evaluation under 9-point hedonic scale for colour, taste, flavour, mouth feel. 21

47 Chapter IV RESULTS AND DISCUSSION This chapter deals with the results of investigations carried out for optimization of process parameters for solid and liquid jaggery preparation, the physical, chemical quality parameters and results of sensory evaluation of solid and liquid jaggery are discussed. 4.1 Analysis of Fresh Neera Fresh neera was analysed for ph and total soluble solids (TSS) in Brix according to lime per cent in Table 3.2 is given in Table 4.1. Causes for differences in values of ph and TSS of neera include the quality of lime used in pre-treatment and uniform application of lime in earthen pot. Table 4.1. Analysis of fresh neera samples Sample Collection date and time Lime % ph TSS ( Brix) 1 17/12/11 and 6.50 am /12/11 and 6.30 am /12/11 and 6.30 am /12/11 and 7.00 am /12/11 and 6.10 am /12/11 and 6.45 am /12/11 and 6.50 am /12/11 and 6.10 am /12/11 and 6.55 am /12/11 and 6.00 am /12/11 and 6.20 am /12/11 and 6.15 am /12/11 and 6.45 am /12/11 and 6.00 am /12/11 and 6.10 am Optimization of Operational Parameters The experimental data for dependent parameters (total sugars, ash and moisture content) at different combinations of process parameters are presented in Table

48 Table 4.2. Effect of process parameters on total sugar (S), ash (A) and moisture content (M) of jaggery Expt. No. Lime, % (X 1 ) Temperature, C (X 2 ) Time, min (X 3 ) Total sugars, % Ash, % Moisture content, % Where X 1 = Lime %, X 2 = Temperature C, X 3 = Time min; S= Total Sugars, A= Ash and M=Moisture content. The estimated regression coefficients of the quadratic polynomial models for the response variables are given in Table 4.3. Table 4.3. Regression coefficients of the second order polynomial model for total sugar, ash and moisture content (coded values) Estimated coefficients Variables S A M Intercept x x x x 1 x x 1 x x 2 x x 1 2 x 2 2 x R CV APR S = Total sugars; A= Ash; M=Moisture content The estimated regression coefficients of the quadratic polynomial models for the response variables, along with coefficient of variation (CV) and Adequate Precision Ratio (APR) are given in Table 4.3. Total sugar has high intercept estimated coefficient value (89.99) compared to ash (2.01) and moisture content (4.98). Single and interaction effects of lime per cent (x 1 ), temperature C (x 2 ) and time min (x 3 ) has less estimated 23

49 coefficient values. Coefficient of determination (R 2 ) of ash (0.98) is slightly higher than total sugar (0.97) and moisture content (0.97) Total sugar The analysis of variance (ANOVA) of total sugar is presented in Table 4.4. The ANOVA data shows very high model F value (35.72) suggesting that the quadratic model can be successfully used to fit the experimental data (p<0.001). F values indicated that the linear terms of independent variable lime significantly affected the total sugar (p<0.001). However, the quadratic terms of temperature affected the total sugar at 5 per cent level of significance (p<0.05). No significant effect was observed in interaction terms of all variables as well as quadratic terms (Table 4.4). The nonlinear second order regression equation was developed as a function of real values of independent variables viz., x 1, x 2 and x 3 for the dependent variable total sugar. The developed relation with actual values (after deleting non-significant terms) has been given in equation S = x1 0.12x x1 0.14x x3 ( R = 0.97) (4.1) The high value of coefficient of determination (R 2 ) and difference of predicted R 2 (0.77) and adjusted R 2 (0.97) less than 0.20 indicated that the developed model was fitted. The value of CV (0.25) less than 10, and APR (22.68) greater than 4 shows the adequate precision and reliability of the experiment and model. Non-significant lack of fit indicated that the regression equation was well fitted for the experimental values. Table 4.4. Analysis of variance showing the effect of lime, time and temperature on total sugars Source Sum of Squares Df Mean Square F Value p value Prob > F Model < *** x < *** x ns x ns x 1 x ns x 1 x ns x 2 x ns x 1 2 x 2 2 x ns * ns Residual Lack of Fit *** P<0.001; ** P<0.01; * P<0.05; ns Non-significant 24

50 From Table 4.4, it was observed that model on total sugar was fitted well with values of sum of square (16.44), degrees of freedom (9), mean square (1.83) and F value of The model predicted response surface for the interaction of independent variables on total sugar is shown in Fig. 4.1(a) to 4.1(c). 92 % Total s ugars ` B: Temperature C A: Lime % Figure 4.1(a). Response surface plot showing the effect of lime and temperature on total sugars at constant time 150 min Fig. 4.1 (a) shows that the response surface plot of total sugars as function process of variables lime and temperature indicated that at low temperature, the lime percent effect on total sugars was less. When temperature increases the total sugars increases with increase in lime. The reason behind the increase in total sugars with increase in lime was that fermentation of carbohydrates in sap arrested at 2.1 per cent of lime compared to 0.9 per cent. Evaporation of more water with increase in temperature results the high total sugars. The results agreed with literature (Ghosh et al., 1998) as temperature and lime increases, total sugars increased. 25

51 92 % Total sugars C: Time min A: Lime % Figure 4.1(b). Response surface plot showing the effect of lime and time on total sugars at constant temperature 117 C Fig. 4.1 (b) shows that the response surface plot of total sugars as lime and time indicated that (i) total sugar content decreased its value from about 90.4 per cent, at 126 min of time and 0.9 per cent of lime to about 90 per cent when the lime percentage increased to 2.1 per cent at the constant time of 126 min but at higher time the total sugars percentage increased from 89.8 to maximum of 90.5 percentage when the lime percentage increased from 0.9 per cent to 2.1 per cent (ii) Total sugars content 90.4 per cent at 126 min of time and 0.9 per cent of lime. The total sugar content decreased slightly to 85.3 per cent when the time increased to 150 min and thereafter slightly increasing trend in total sugar percentage was observed up to 89.8 per cent, at 174 min of time and 0.9 per cent lime. Similar trend i.e. slightly decreases and thereafter increases in total sugars when the time increases was observed when the lime concentration increase to 2.1 per cent. The reasons behind the increase in total sugars with increase in both lime and time was due to the fact that the saps fermentation was arrested more at 2.1 per cent of lime compared to 0.9 per cent and during higher boiling times all the water evaporates quickly leaving behind only sugars. Although there is less reported literature on effect of total sugars on lime and time, it was clear on analysis of fresh neera as well as in sensory evaluation. 26

52 92 % 91 Total sugars C: Time min B: Temperature C Figure 4.1(c). Response surface plot showing the effect of temperature and time on total sugars at constant lime 1.5 percent Fig. 4.1 (c) shows that the response surface plot of total sugar as temperature and time indicated that (i) total sugars slightly increased its value from about 90 per cent; at 126 min of time and 113 C of temperature to 90.4 per cent when the temperature rose to 121 C at 126 min time. (ii) Total sugars starts its value from about 90 per cent; at 126 min of time and 113 C of temperature follows decreasing trend up to middle point and thereafter follows increasing trend up to 89.6 per cent at 174 min at 113 o C temperature. (iii) Increase in total sugars was observed at higher temperature and higher time and reached a maximum value of 90.8 per cent at 174 min of time 121 o C temperature. The reasons behind the increase in total sugars with increase in both time and temperature was due to the fact that during higher boiling times all the water evaporates quickly leaving behind only sugars and evaporation of more water with increase in temperature results the high total sugars respectively. Model indicated that the total sugar has positive effect on both time and temperature Ash The analysis of variance (ANOVA) of ash content of solid jaggary is presented in Table 4.5. The ANOVA data set shows very high model F value (12.81) suggesting that the quadratic model can be successfully used to fit the experimental data (p<0.001). F 27

53 values indicated that the linear terms of independent variables lime and temperature significantly affected the ash content (p<0.001). However, the quadratic terms of lime and temperature affected the ash at 5 per cent level of significance (p<0.05). No significant effect was observed in interaction terms of all variables as well as quadratic term of time on ash (Table 4.5). The nonlinear second order regression equation was developed as a function of real values of independent variables viz., x 1, x 2 and x 3 for the dependent variable ash. The developed relation with actual values (after deleting nonsignificant terms) has been given in equation A = x x x x3 ( R = 0.98) (4.2) The high value of coefficient of determination (R 2 ) and difference of predicted R 2 (0.91) and adjusted R 2 (0.97) less than 0.20 indicated that the developed model was correct. The value of CV (5.74), less than 10, and APR (38.6), greater than 4, shows the adequate precision and reliability of the experiment and model. Non-significant lack of fit indicated that the regression equation was well fitted for the experimental values. Table 4.5. Analysis of variance showing the effect of lime percent, time and temperature on ash content Source Model x 1 x 2 x 3 x 1x 2 x 1x 3 x 2x 3 2 x 1 2 x 2 2 x 3 Residual Lack of Fit Sum of Squares Df Mean Square F Value p value Prob > F < *** < *** ns ns ns ns ns * * ns *** P<0.001; ** P<0.01; * P<0.05; ns Non-significant From Table 4.5, it was observed that model on ash content was fitted significantly well with values of sum of square (12.81), degrees of freedom (9), mean square (1.42) and F-value (102.76) at P< Single effect of lime (x 1 ) was fitted significantly well 28

54 with values of sum of square (12.46), degrees of freedom (1), mean square (12.46) and F-value (899.59) at P< Remaining single effects and their interactions were non significant. The model predicted interaction of independent variable response surface on ash content is depicted in Fig. 4.2 (a) to 4.2 (c) % 2 Ash B: Temperature C A: Lime % Figure 4.2(a). Response surface plot showing the effect of lime and temperature on ash content at constant time 150 min Fig. 4.2 (a) shows that response surface plot of ash content as function of process variables lime and temperature indicated that at lower temperature, the ash content was decreased from 1.7 per cent to 1.1 per cent when the lime percentage increased from 0.9 to 2.1 per cent at 113 C. When temperature increases, ash content increases with increase in lime per cent. Ash content increased its value from 1.75 per cent, at 113 C temperature and 0.9 per cent lime to about 2 per cent, at 121 C and 0.9 per cent lime. As the lime percentage increased to 2.1 per cent at 121 C the ash content reaches maximum value of 2.5 per cent. The reason behind the increase in ash content with increase in temperature was due to the fact that during heating inorganic residue increases with evaporation of water content in the form of vapours. Ash decreases with increase in lime content was due to the fact that lime arrests fermentation of sap causing incomplete destruction of organic matter. 29

55 3 2.5 % 2 Ash C: Time min A: Lime % Figure 4.2(b). Response surface plot showing the effect of lime and time on ash content at constant temperature 117 C Fig. 4.2 (b) shows that response surface plot of ash as lime and time indicated that the ash content is not changed when the lime percentage increased. The ash content value 2.1 per cent at 0.9 per cent lime and 126 min and ash content value slightly changed to 2.04 per cent as the lime percentage increased to 2.1 per cent at 126 min time. Ash content has a relatively less effect of lime and more effect of time was noticed. Ash content starts its value from 2.1 per cent at 0.9 per cent lime and 126 min time and follows decreasing trends in parabolic paths from 126 min to 150 min of heating time thereafter increased to 2.2 per cent ash content at 174 min. The reason behind the increase in ash content with increase in heating time was due to the fact that during boiling inorganic residual matter increases. Ash decreases with increase in lime content was due to the fact that lime arrests fermentation of sap causing incomplete destruction of organic matter. 30

56 3 2.5 % Ash C: Time min B: Temperature C Figure 4.2(c). Response surface plot showing the effect of temperature and time on ash content at constant lime 1.5 per cent Fig. 4.2 (c) shows that response surface plot of ash as function process of variables temperature and time indicated that the ash content increased from 1.8 per cent, at 113 C and 126 min to about 2.5 per cent, at 121 C and same time. Ash content starts its value from 1.8 per cent, at 113 C and 126 min and follows decreasing trend till the time reaches 150 min time there after percentage of ash content increased when the time increases. Ash content finally reached a point of 1.7 per cent, at 174 min and 113 C temperature. As there is less proven literature on lime, temperature and time effects on ash content, based on the observations in preliminary trials as well as in chemical analysis it was concluded that ash content was significantly affected with lime, but negligible effect with the time and temperature Moisture content The ANOVA of moisture content is presented in Table 4.6. The ANOVA data set shows very high model F value (32.11) suggesting that the quadratic model can be successfully used to fit the experimental data (p<0.001). F values indicated that the linear terms of independent variables time significantly affected the moisture content (p<0.001). However, the quadratic term of temperature affected the moisture content at 5 per cent level of significance (p<0.05). No significant effect was observed in interaction terms of all variables as well as quadratic terms of lime and time except temperature as shown in Table 4.6. The nonlinear second order regression equation was 31

57 developed as a function of real values of independent variables viz., x 1, x 2 and x 3 for the dependent variable moisture content. The developed relation with actual values (after deleting non-significant terms) has been given in equation M = x1 1.49x x x x 3 ( R = 0.97) (4.3) The high value of coefficient of determination (R 2 ) and difference of predicted R 2 (0.91) and adjusted R 2 (0.97) less than 0.20 indicated that the developed model was correct. The value of CV (5.74), less than 10, and APR (38.6), greater than 4, shows the adequate precision and reliability of the experiment and model. Non-significant lack of fit indicated that the regression equation was well fitted for the experimental values. Table 4.6. Analysis of variance showing the effect of lime percent, time and temperature on moisture content Source Sum of Squares Df Mean Square F Value p value Prob > F Model < *** x x < *** x ns x 1 x ns x 1 x ns x 2 x ns x 1 2 x 2 2 x ns * ns Residual Lack of Fit *** P<0.001; ** P<0.01; * P<0.05; ns Non-significant From Table 4.6, it was observed that the model on moisture content was fitted well with the values of sum of squares (32.11), degrees of freedom (9), mean square (3.57) and F-value (32.67) at P< Interaction effects were non significant. The model predicted interaction of independent variable response surface on moisture content is depicted in Fig. 4.3 (a)-(c). 32

58 8 % Moisture content B: Temperature C A: Lime % Figure 4.3(a). Response surface plot showing the effect of lime and temperature on moisture content at constant time 150 min Fig. 4.3 (a) shows that response surface plot of moisture content as lime and temperature indicated that moisture content decreased from about 5.3 per cent at 0.9 per cent of lime and 113 C of temperature to about 4.3 per cent at same lime per cent and 121 C of temperature. Moisture content increased from about 5.2 per cent at 2.1 per cent of lime and 113 C of temperature to about 5.7 per cent at 121 C of temperature and same lime content. Moisture content decreased with increase in temperature and it was not changed when lime percent increased. The reason behind the decrease in moisture content with increase in temperature was may be due to cooled jaggery has less moisture content compared to boiling syrup. 33

59 8 % Moisture content C: Time min A: Lime % Figure 4.3(b). Response surface plot showing the effect of lime and time on moisture content at constant temperature 117 C Fig. 4.3 (b) shows that response surface plot of moisture content as lime and time indicated that moisture content increased drastically from 4.2 per cent, at 0.9 per cent lime and 126 min time to about 6.8 per cent, at 2.1 per cent lime and same time. Moisture content slightly decreased from 6.8 per cent, at 2.1 per cent lime and 126 min time to about 4.5 per cent, at 0.9 per cent lime and 174 min. Moisture content increased drastically from 4.2 per cent, at 0.9 per cent lime and 126 min time to about 5.4 per cent, at 174 min and same lime content. The reason behind the increase in moisture content with increase in both lime and time which may due to increase in lime percent will increase the hygroscopes of jaggery and bound water present in the bio colloids of sugar syrup will take longer boiling times to separate respectively. 34

60 8 % Moisture content C: Time min B: Temperature C Figure 4.3(c). Response surface showing the effect of temperature and time on moisture content at constant lime 1.5 per cent Fig. 4.3 (c) shows that response surface plot of moisture content as temperature and time indicated that moisture content decreases its value from about 6.3 per cent, at 113 C and 126 min to about 5.6 per cent at 121 C temperature and same time. Moisture content slightly decreased from 5.6 per cent at 113 C and 126 min to about 5.2 per cent at 113 C and 174 min. Moisture content decreased to 4.7 per cent at higher time (174 min) and temperature (121 C). The results indicate that moisture content of jaggery was affected by temperature and little effect with respect to both time and lime content. There is less proven literature on palmyrah palm jaggery, but it similar to cane jaggery and agreement with the same Optimization of process variables The graphical optimization of process variables was done using Design Expert software. Firstly, the range of optimized responses was achieved numerically by putting the values of operational variables following the goal presented in Table

61 Table 4.7. Optimization criteria for different operational variables and responses Variables and responses Goal Importance Lime, % is in range +++ Temperature, C is in range ++++ Time, min is in range +++ Total sugars, % Maximize ++++ Ash, % Minimize ++ Moisture content, % Minimise ++ In result of numerical optimization, the optimal total sugar, ash and moisture content obtained are per cent, 2.88 per cent and 3.90 per cent respectively. So, among fifteen combinations the best combination suited was lime 2.1 per cent, temperature 121 C and time 174 min. 4.3 Proximate Composition The proximate composition of jaggery at lime 2.1 per cent, temperature 121 C and time 174 min is presented in Table 4.8 and liquid jaggery at 108 C is chosen to estimate proximate composition. Variation in proximate compositions of solid and liquid jaggery can be observed from the table 4.8 shown below. Table 4.8. Proximate composition of solid and liquid jaggery Item Moisture, %, d.b Fat, % Protein, % Ash, % Carbohydrate, % (by difference) Solid Liquid Control Sensory Evaluation of Quality parameter of Solid Jaggery The sensory scores of jaggery were analyzed as described under section 3.7 of materials and methods. 36

62 4.4.1 Sensory evaluation of solid and liquid jaggery samples using 9-point hedonic scale Results of sensory scores of nine jaggery samples were presented in Table 4.9 in terms of quality attributes namely, colour, taste, flavour and texture (Plate 4.1). (a) (b) Plate 4.1. Palmyra palm jaggery samples The samples S 4, S 5, S 7, and S 9 had higher scores for colour; S 1, S 4, S 5, S 6 and S 7 for taste; samples S 1, S 4, S 5, S 7 and S 9 for flavour; and samples S 1, S 4, S 5, and S 7 for texture (Table 4.9). Finally, the jaggery sample S 4 scores well among nine samples in terms of quality attribute. Table 4.9. Sensory evaluation of solid jaggery samples Quality attributes S 1 S 2 S 3 S 4 S 5 S 6 S 7 S 8 S 9 Colour Taste Flavour Texture Table 4.10 furnishes the sensory evaluation data for liquid jaggery samples. The sample L 3 ranks higher for colour, L 5 ranks higher for taste and flavour, L 3 ranks higher for mouth feel. Table Sensory evaluation of liquid jaggery samples Quality attributes L 1 L 2 L 3 L 4 L 5 Colour Taste Flavour Mouth feel