DEVELOPMENT OF FIBRE FORTIFIED LOW FAT CRANBERRY ICE CREAM

Transcription

1 DEVELOPMENT OF FIBRE FORTIFIED LOW FAT CRANBERRY ICE CREAM THESIS SUBMITTED TO THE NATIONAL DAIRY RESEARCH INSTITUTE, KARNAL (DEEMED UNIVERSITY) IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF MASTER OF TECHNOLOGY IN DAIRY TECHNOLOGY BY MUKESH KUMAR B.Tech (Dairy Technology) DIVISION OF DAIRY TECHNOLOGY NATIONAL DAIRY RESEARCH INSTITUTE (DEEMED UNIVERSITY) KARNAL (HARYANA), INDIA 2013 Regn. No

2 DEDICATED TO MY LOVING PARENTS & MY SISTER

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5 ACKNOWLEDGEMENT First and foremost, I would like to pay my obeisance to God Almighty for always bestowing me with His blessings without which I could not have achieved anything that I have today. I offer my sincerest gratitude to my advisor, Dr. R.R.B. Singh, who has supported me throughout my research with his patience and knowledge whilst allowing me the room to work in my own way. I also thank him for his excellent guidance, caring, patience, and providing me with an excellent atmosphere for doing research. I attribute the level of my Masters degree to his encouragement and effort and without him this thesis, too, would not have been completed or written. He let me experience the research of freshwater mussels in the field and practical issues beyond the textbooks, patiently corrected my writing and supported my research. One simply could not wish for a better or friendlier supervisor. This thesis would not have been possible without the help, support and guidance of my advisory committee members, Dr. I.K. Sawhney (Principal Scientist, DE), Dr. Kaushik Khamrui (Sr. Scientist, DT), Dr. S.K. Tomar (Principal Scientist, DM) and Dr. (Mrs.) Bimlesh Mann (Principal Scientist, DC). I extend my sincere thanks to Dr. A.K. Srivastava, Director, NDRI, Karnal and Dr. G.R. Patil, Joint Director (A) NDRI, Karnal for providing all necessary facilities to carry out the present investigation. I am extremely grateful to Dr. A. A. Patel, Head, Dairy Technology Division, Dr. S.K. Knawjia, Dr. S. Singh, Dr. A.K. Singh and Dr. V.K. Gupta for inspiring and valuable suggestions, constructive criticism and timely help during the entire period of study. I gratefully acknowledge the guidance and help that I received throughout the study from Mr. Yogesh Khetra, Mr. P.N. Raju, Mr. M.H. Sathish, Mr. G.S. Meena, Mr. Prateek Sharma, Mr. Devraja H.C. and Mr. Abdul Shaikh. I humbly acknowledge the valuable help and all the possible cooperation extended by Rampal ji, Satish bhai, Jile Singh ji and the staff of experimental dairy and UG/PG lab, DT division, NDRI especially during trials. I am also thankful to my seniors, Richa mam (sweetu mam), Omkar sir, Prmod sir, Pravin sir (UK sir), Bihari sir, Rahul sir, Wridhama sir (farzi no. 1), Anuj sir (chaubbe lal), Akanksha mam (kanchi mam), Upasana mam (Upi mam), Dipesh sir, Sangeeta mam and others.

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7 Abstract Ice cream is one of the most widely consumed dairy products in the world. However, most of the commercially available ice cream brands are rich in fat and sugar but generally poor in natural antioxidants. In recent years, greater consumer awareness has led to increased demand for functional and low fat foods. Therefore, need was felt to develop ice cream with enhanced nutritional and functional attributes but without compromising on its traditional taste. It was envisaged that this could possibly be achieved by reducing fat content, and incorporating polyphenol rich fruit juice and fibre into the ice cream formulation. Thus, the present study was proposed to develop standard quality reduced fat ice creams enriched with dietary fibre and cranberry juice. The levels of sugar, stabilizer and emulsifier blend and cranberry juice concentrate (12% TS) of the ice cream were optimized using a Central Composite Rotatable Design (CCRD) of Response Surface Methodology (RSM) separately for low and medium fat ice cream. Cranberry juice concentrate addition had significant effect on colour scores of both ice cream, however the effect was more significant for medium fat ice cream (p<0.01) as compared to low fat ice cream (p<0.05) at linear level. Effect of stabilizer and emulsifier blend on body and texture was negatively significant and effect of cranberry juice concentrate was also negatively on the overall acceptability for both types of ice cream. The Hunter lab a* value and acidity of ice cream also increased significantly (p<0.01) with increase in the level of cranberry juice concentrate at linear level. Optimized cranberry ice cream had high acidity (~0.63% of LA) than control ice cream (0.25% of LA). Cranberry ice cream had higher amount of polyphenol (2.5x10 3 GAE/g for low fat and 2.56x10 3 for medium fat) and antioxidant capacity ( µm of trolox equivalent / g for low fat and µm of trolox equivalent / g for medium fat). Stabilizer and emulsifier blend had highly positive significant effect (p<0.01) on viscosity, storage modulus and loss modules but negative significant effect (p<0.01) on melting rate of both the types of ice cream. Medium fat, fibre fortified cranberry ice cream was found to have higher desirability (0.84) than low fat ice cream (0.69). The optimized low fat ice cream formulation contained 5.5% fibre blend (4% inulin, 1% oat bran, 0.3% psyllium husk and 0.2% wheat fibre), 2.5% fat, 12.01% sugar, 0.55% stabilizer and emulsifier blend and 7.7% cranberry juice concentrate; while the medium fat optimized ice cream had 5.5% fibre blend, 6% fat, 16% sugar, 0.2% stabilizer and emulsifier blend and 8.04% cranberry juice concentrate.

8 र ष ट र य ड यर अन श ध न स स थ न, करन ल र श स सम द व कम वस व ल क र नब र रस य क त आइसक र म क ववक स श ध थ : म क श क म र म र गदशगक : ड. आर. आर. ब. सस ह स र श आइसक र म द न य म सबस अध क उपभ ग ह व ल द ग उत प द म स एक ह, ल कक व य वस नयक र प स उपलब आइसक र म म प र क न क ऑक स करण र कम ह ह और यह वस और शक कर म सम द भ म ज ह ह ल क वर ष म, बढ़ उपभ क ज गर क क द ख ह ए और क य त मक और कम वस आइसक र म क म ग बढ़ गई ह इसक द ख ह ए प र षक और क य त मकग ण स प ण एव प र मपर क स व द और आ द स पर प ण आइसक र म य र कर क जर र प ई गई इसक ध य म रख ह ए, यह म ह म न क ल गई क आइसक र म म वस क कम ककय ज ए थ प ल फ ल स सम द फल क रस और र श क सम व श ककय ज ए इनह थ य क मद जर, उपभ क व म अघ यय क द व र एक कम वस व ल र श स भरप र क र ब र रस य क आइसक र म ववकस कर क प रस व रख गय प रत य त र भ ल पद न (आर.एस.एम.) क क नर य ममध र पर ख (स.स.ड.) क द व र कम एव मध य न र वस व ल आइसक र म क श कक कर, स ट बल इजर और प यस क रक मम ण और क र ब र स नर रस (क ल ठ स 12 प रन श ) क स र न र ककय गय क र ब र स नर रस क द प रक र क आइसक र म क र ग क अ क पर महत वप ण प रभ व पड द ख गय जबक कम वस आइसक र म (p<0.05) क ल म मध यम वस आइसक र म (p<0.01) पर इसक ज य द महत वप ण प रभ व पड द ख गय द प रक र क आइसक र म क आक र व रच पर स ट बल इजर और प यस क रक मम ण क प रभ व और समग र स व क य पर क र ब र रस क प रभ व क र त मक र प स मह तत वप ण प य गय आइसक र म क ह टर एलएवव a * और अम ल क स र म क र ब र स नर रस क म त र क व वद क स थ र ख य स र पर व वद द ख गय न र क र ब र आइसक र म क अम ल (~0.63 प रन श ल क क टक एस ड) न य त र आइसक र म (0.25 प रन श ल क क टक एस ड) क ल म अघ क प य गय न र आइसक र म म प ल फ ल (मध यम वस क मलए 2.56x10 3 ज एइ प रन ग र म और कम वस मलए 2.5x10 3 ज एइ प रन ग र म) और ऑक स करण र क षम (मध यम वस क मलए म इक र म ल ट र ल क स सम ल य प रन ग र म और कम वस क मलए म इक र म ल ट र ल क स सम ल य प रन ग र म) भ अघ क प य गय स ट बल इजर और प यस क रक मम ण क प रभ व श कय, भ ड रण म ड य ल और कस म ड य ल पर महत वप ण (p<0.01) और सक र त मक रह ल कक इसक प रभ व वपघल क दर पर महत वप ण (p<0.01) और क र त मक द ख गय मध यम वस व ल आइसक र म (0.84) कम वस व ल आइसक र म (0.69) क ल म अध क अच छ प य गय कम वस व ल आइसक र म म 5.5 प रन श र श क मम ण (4 प रन श इ ल, 1 प रन श जई च कर, 0.3 प रन श इसबग ल भ स और 0.2 प रन श ग ह क र श ), 2.5 प रन श वस, प रन श शक कर, 0.55 प रन श स ट बल इजर और प यस क रक मम ण और 7.7 प रन श क र ब र स नर रस क न र क य गय जबक मध यम वस व ल आइसक र म म म 5.5

9 प रन श र श क मम ण, 6 प रन श वस, 16 प रन श शक कर, 0.20 प रन श स ट बल इजर और प यस क रक मम ण और 8.04 प रन श क र ब र स नर रस क न र क य गय

10 CONTENTS Chapter No. Title Page No. 1 INTRODUCTION REVIEW OF LITERATURE History of ice cream Ice cream definition Legal standards of ice cream Ice cream market Low fat ice cream Fruits ice cream Functional foods Antioxidant activity of fruits Antioxidant potential of berry fruits Cranberry Dietary fibre Functional properties of dietary fibre Psyllium husk Oat bran Inulin Fat replacer Physico chemical properties of ice cream Acidity Specific gravity Viscosity Fat destabilization Mix stability 24

11 Over run Melting rate Organoleptic characteristics of ice cream Stabilizer and emulsifier 25 3 MATERIALS AND METHODS Materials/ingredients Milk Cream Spray dried skim milk powder Sweetener Cranberry juice concentrate Stabilizer and emulsifier Dietary fibre Oat bran Inulin Psyllium husk Wheat fibre Packaging material Equipments Gerber centrifuge Zeal lactometer ph meter Pasteurization vat Homogenizer Freezer Hardening unit 30

12 3.3.8 High speed refrigerated centrifuge Optimization of cranberry concentrate supplemented ice cream Methods of manufacture of ice cream Ice cream mix and ice cream preparation Figuring of mix Mixing of ingredients Homogenization Pasteurization Cooling and ageing Freezing Filling Hardening Analytical method Analysis of milk Fat SNF Acidity Analysis of ice cream mix and ice cream Sensory evaluation ph Titratable acidity Total solids Over run Melting rate Fat 34

13 Protein Total sugar Antioxidant activity of cranberry ice cream Assay for DPPH radical scavenging activity Analysis of total phenolic content Instrumental Analysis Hardness Colour 41 Rheological Properties a. Viscosity 41 b. Frequency sweep test Sensory evaluation Statistical analysis 42 4 RESULTS AND DISCUSSION Selection of level of fat, fibre blend and range of sugar, cranberry juice concentrate and stabilizer and emulsifier blend Optimization of ingredients by employing response surface methodology (rsm) for having product with maximum acceptability Effect of different levels of sugar, cranberry juice concentrate and stabilizer and emulsifier on sensory characteristics of low fat ice cream Diagnostic check of the quadratic model Effect of sugar, cranberry juice concentrate and stabilizer and emulsifier blend level on colour and appearance of ice cream 44

14 Effect on body and texture score Effect on mouthfeel score Effect on sweetness Effect on flavour Effect on overall acceptability Effect of different ingredients on physco chemical properties of low fat ice cream mix and ice cream Effect on over run Effect on hardness Effect on acidity Effect on melting rate Effect on viscosity Effect on total solid Effect on colour value of hunter lab a* Effect on colour value of hunter lab b* Effect on storage modulus (G ) Effect on loss modulus (G ) Effect of different levels of sugar, cranberry juice concentrate and stabilizer and emulsifier blend on sensory characteristics of medium fat ice cream Effect on colour and appearance Effect on body and texture score 88

15 Effect on mouthfeel score Effect on sweetness Effect on flavour Effect on overall acceptability Effect of different ingredients on physico chemical properties of medium fat ice cream mix and ice cream Effect on acidity Effect on melting rate Effect on viscosity Effect on total solid Effect on colour value of a* Effect on colour value of b* Effect on storage modulus (G ) Effect on loss modulus (G ) Optimized solutions and their validation Chemical composition of ice cream SUMMARY AND CONCLUSION Optimization of levels of ingredients for low and medium fat ice cream Effect of level of ingredients on sensory characteristics of low fat cranberry ice cream Effect of ingredients on physico-chemical parameters of low fat ice cream 117

16 5.4 Effect of three independent variables on sensory characteristics of medium fat cranberry ice cream Effect of three independent variables on physicochemical parameters of low fat ice cream Optimized solution and its validation Chemical composition of optimized ice cream 119 Bibliography i-xii Annexure

17 LIST OF TABLES Table No. Title Page No. 2.1 FSSR requirements for ice cream and frozen dessert Microbiological standards for ice cream Representative formulae for ice cream of different grades The percentage market share of different ice cream brands in India Functional properties of some ingredients Composition of cranberry Composition of oat bran Composition of inulin The design matrix for low fat ice cream using three independent variables: Sugar, Stabilizer & Emulsion blend and Cranberry juice The design matrix for low fat ice cream using three independent variables: Sugar, Stabilizer & Emulsion blend and Cranberry juice Effect of sugar, stabilizer and emulsifier blend and cranberry juice concentrate on sensory properties of low fat ice cream Regression coefficients and ANOVA of fitted quadratic model for sensory characteristics of low fat Ice Cream Physico Chemical characteristics of low fat Ice cream made with different levels of sugar, stabilizer and emulsifier blend and cranberry juice concentrate Regression coefficients and ANOVA of fitted quadratic model 50

18 for physico-chemical characteristics of low fat Ice cream 4.7 Effect of sugar, stabilizer and emulsifier blend and cranberry juice concentrate on sensory properties of formulated medium fat ice cream Regression coefficients and ANOVA of fitted quadratic model for sensory characteristics of medium fat Ice Cream Physico - Chemical characteristics of medium fat Ice cream made with different levels of sugar, stabilizer and emulsifier blend and cranberry juice concentrate Regression coefficients and ANOVA of fitted quadratic model for physico-chemical characteristics of medium fat Ice cream Goals set for RSM constraints to optimize the low fat Ice Cream Goals set for RSM constraints to optimize the medium fat Ice Cream Optimized Solution of low fat cranberry Ice Cream Optimized Solution of medium fat cranberry Ice Cream Predicted and observed values of low fat Ice Cream Predicted and observed values of medium fat Ice Cream Proximate composition of low fat ice cream Proximate composition of medium fat ice cream 115

19 Fig. No. 3.1 List of Figures Title General flow diagram for the preparation of cranberry ice cream Page No Standard curve of Trolox by DPPH method Standard curve for estimation of total phenolic content Response surface curve for colour and appearance of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for colour and appearance of low fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for colour and appearance of low fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for body and texture of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for body and texture of low fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for body and texture of low fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for mouthfeel of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend

20 4.8 Response surface curve for mouthfeel of low fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for mouthfeel of low fat ice cream as Influenced by level of stabilizer and emulsifier blend and stabilizer and emulsifier blend Response surface curve for sweetness of low fat ice cream as Influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for mouthfeel of low fat ice cream as Influenced by level of sugar and cranberry juice concentrate Response surface curve for mouthfeel of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for flavour of low fat ice cream as influenced by level of cranberry sugar and stabilizer and emulsifier blend Response surface curve for flavour of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for flavour of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Surface curve for overall acceptability of low fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for overall acceptability of low fat Ice cream as influenced by level of cranberry juice concentrate and sugar

21 4.18 Response surface curve for overall acceptability of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for over run of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for over run of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for over run of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for hardness of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for hardness of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for hardness of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for acidity of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for acidity of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for acidity of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend

22 4.28 Response surface curve for melting rate of low fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for melting rate of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for melting rate of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for viscosity of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for viscosity of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for viscosity of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for total solid of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for total solid of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for total solid of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for a* of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend

23 4.38 Response surface curve for a* of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for a* of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for b* of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for b* of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for b* of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for G of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for G of low fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for G of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for G of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for G of low fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend 81

24 4.48 Response surface curve for G of low fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for colour and appearance of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for colour and appearance of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for colour and appearance of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for body and texture of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for body and texture of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for body and texture of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for mouthfeel of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for mouthfeel of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar 91

25 4.57 Response surface curve for mouthfeel of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for sweetness of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for sweetness of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for sweetness of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for flavour of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for flavour of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for flavour of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for overall acceptability of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for overall acceptability of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar 96

26 4.66 Response surface curve for overall acceptability of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for acidity of medium fat ice cream as influenced by level of sugar and stabilizer and emulsifier blend Response surface curve for acidity of medium fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for acidity of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for melting rate of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for melting rate of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for melting rate of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for viscosity of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for viscosity of medium fat ice cream as influenced by level of sugar and cranberry juice concentrate 101

27 4.75 Response surface curve for viscosity of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for total solid of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for total solid of medium fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for total solid of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for a* of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for a* of medium fat ice cream as influenced by level of sugar and cranberry juice concentrate Response surface curve for a* of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate Response surface curve for b* of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for b* of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for b* of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and cranberry juice concentrate

28 Response surface curve for G of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for G of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for G of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend Response surface curve for G of medium fat ice cream as influenced by level of stabilizer and emulsifier blend and sugar Response surface curve for G of medium fat ice cream as influenced by level of cranberry juice concentrate and sugar Response surface curve for G of medium fat ice cream as influenced by level of cranberry juice concentrate and stabilizer and emulsifier blend 110

29 LIST OF NOTATION AND ABBREVIATION USED % Percentage C Degree Celsius µ Micron AACC ANOVA AO AOAC APV CCD CCRD cfu CHD cm cp CVD DF DPPH et al. FAO g GAE h ICMR Kg L American Association of Cereal Chemist Analysis of Variance Antioxidant Association of Officials and Analytical Chemists Adequate precision value Central Composite Design Central Composite Randomization Colony Forming Units Coronary Heart Disease Centi Metre Centi Poise Cardio Vascular Disease Dietary Fibre 2, 2-Diphenyl-1-picrylhydrazyl and co-workers Food and agriculture organization Gram Gallic acid equivalent Hour Indian Council of Medical Research Kilogram Litre

30 LA LDL LDPE Mg Min ml MSNF MT N NaOH NLEA NS Pa ph PP PRESS rpm RSM Sec SMP SPC TPA Trolox TS Viz. Lactic Acid Low Density Lipoprotein Low Density Polyethylene Milligram Minute Millilitre Milk Solids Not Fat Million Tones Normality Sodium Hydroxide Nutritional Labelling and Education Act Non-significant Pascal Negative log of the hydrogen ion concentration Polyphenol Predicted Residual Error Sum of Squares Rotation per Minute Response Surface Methodology Second Skimmed Milk Powder Standard Plate Count Texture Profile Analysis 6-hydroxy. 2, 5, 7, 8 tetramethyl chroman-2- carboxylic acid Total Solids Namely

31 Chapter-1 INTRODUCTION

32 1. INTRODUCTION The name Ice Cream is derived from - phrase "Iced Cream". Ice cream is a delicious, wholesome and nutritious frozen dairy product. It is a popular dairy product liked by all age groups. It is stored at refrigerated temperature and consumed also in the frozen state. Ice cream is a complex colloidal frozen dairy dessert, which consist of partially coalesced fat droplets, air cells, ice crystals and a continuous aqueous phase, in which the polysaccharides, proteins, lactose and mineral salts are dispersed. Ice cream is an oil in water type emulsion. Ice cream consists by mainly three phases, viz., ice crystal, air bubble, and fat globules. The year on year growth of the ice cream has been consistently at about 15% by volume and 20% by value over the last few years. Indian ice cream market is about 350 million liters per annum valued at about 21,000 million of which about 65% is with the organized sector. The per capita annual consumption of ice cream is still at 0.25 litres as against nearly 12 litres of the USA (Saxena, 2007). It can therefore be visualized that the sector offers enormous opportunities for growth. Recently consumers have shown interest towards reduced or low-fat foods because these are associated with a reduced risk of obesity and coronary heart diseases. One of the goals in modifying ice cream formulations is to produce a product with a desirable texture and enhancement of texture will only occur through improvements in the products physical structure (Stanley, Goff and Smith, 1996). The consumption of low-fat foods has become a way of life for many health-conscious people. Generally, Ice cream contains 10-12% fat. But, in recent years, the dairy industry has developed a variety of low-fat and fat-free ice cream. The Food and Drug Administration has permitted the use of reduced-fat, low-fat and non-fat ice creams containing less than 10% milk fat, that is target for health-conscious consumers. Compared with traditional ice creams, the low-fat ice creams suffer from low flavour and textural quality. Texture is more important factor than flavour in determining overall acceptability of the low-fat ice cream. Removal of fat creates body and textural problems, such as coarseness and iciness, crumbly body, shrinkage and flavour defects. In low fat ice cream losses of texture and flavour. Thus, the formulation of food products with low fat content without affecting the sensory and texture is a challenge. Due to demand of low fat foods fat replacers are being used 1

33 INTRODUCTION to fulfil the gap between low fat and full fat foods. Fat substitutes for ice cream may be carbohydrate, protein or lipid based. Fat replacer provide low calorie than traditional fat sources. Ice cream is a good source of important nutrients but like other dairy products ice cream too, lacks in dietary fibre content. High intake of dietary fibre food is directly related to low incidence of many disorders and disease (e.g., chronic bowel disease, diabetes, coronary heart disease and colon cancer). Indian Council of Medical Research (ICMR) has recommended that minimum of g/day dietary fibre should be included in the diet. Inulin is a carbohydrate based fat replacer, is widely used in functional foods throughout the world for its health promoting attribute. Inulin as a fat mimetic has ability to bind water molecules and form a particle gel network. Inulin increases viscosity and hardness. Inulin reduces freezing point and improve the sensory properties of ice cream as well. Free radicals are generated through normal reactions within the body during respiration of aerobic organisms. Excessive amount of free radicals can result in cellular damage which, in turn, initiates several diseases including atherosclerosis, arthritis, diabetes and cancer (Cai et al., 2004). Antioxidant defence systems can remove reactive species through enzymatic (like superoxide dismutase and glutathione peroxidase) and non-enzymatic antioxidants (such as antioxidant vitamins, trace elements, coenzymes and cofactors). Oxidative stress in human usually plays the role of a promoter rather than an initiator of chronic diseases. Therefore, need of natural antioxidants, which can prevent oxidative stress and its deleterious effects. Antioxidants are nutrients in food that protect cells from damage from free radicals. Natural antioxidants from food resources such as phenolic compounds. These have antioxidant and anti-inflammatory properties and may protect against degenerative diseases such as cancer and cardiovascular disease (Bravo, 1998). These compounds are good contributors to the total antioxidant capacity of the foods that contain them and being water soluble compounds these can be easily mixed with milk. An important category of phytochemicals, phenolic compounds are dietary constituents widely existing in plants and have been considered to have high antioxidant capacity and free radical scavenging capacity. There has been an increase in the addition of phenolic compounds to dairy products to improve both their technological functionality and nutritional value (O Connell and Fox, 2001). The effect of the addition of fruit extracts, rich in phenolic compounds, on 2

34 INTRODUCTION the antioxidant and sensory attribute of Ice cream. Cranberries are rich sources of antioxidants and organic acids, including ellagic acid, citric acid, malic acid, quinic acid, flavonoids, proanthocyanidins, anthocyanins, and vitamin C (Vinson, 2001). Therefore adding more value to ice cream by lowering the fat content and incorporating ingredients which are healthful may trigger growth and offer alternatives to such skeptical consumers. Enrichment with fibers and bioactive from cranberry offers such possibilities. Therefore the present study is proposed to develop a formulation which is low in fat but high in fibre and nutraceuticals thus making the product far more functional. Hence, the present study is formulated with the following objectives:- Optimization of the levels of sugar and cranberry juice concentrate in the low fat ice cream formulation incorporated with fibre blend. Evaluation of physico-chemical and rheological properties of the ice cream formulation as a function of processing variables and bioactive properties of the optimized product. 3

35 Chapter-2 REVIEW OF LITERATURE

36 2. REVIEW OF LITERATURE Ice cream is a frozen dairy dessert which is made by combining milk, sweeteners, stabilizers, emulsifiers and flavourings. Other ingredients such as egg and egg products, coloring and starch hydrolysates may also be added. This mixture is called ice cream mix. Ice cream is a complex food colloid that consists of air bubbles, fat globules, ice crystals and an unfrozen serum phase. Ice crystals and air bubbles are usually in the range of µm. Air bubbles are usually partially coated with fat globules and the fat globules are coated with a protein/emulsifier layer. Serum phase consists of sugars and high molecular weight polysaccharides in a freeze-concentrated solution. Various steps in the manufacturing process, including homogenization, pasteurization, ageing, freezing and hardening, contribute to the development of the ice cream. Ice cream mix is homogenized and pasteurized before freezing. During freezing rapid removal of heat takes place while vigorous agitation contributes to incorporation of air, thus resulting in desirable smoothness and softness of the frozen ice cream. Several of these processing steps contribute to fat structure development in ice cream (Goff, 1997). The smooth texture and cooling sensation perceived by consumers on eating ice cream are due to a large degree, to the size, number and shape of the ice crystals present in the product. Sensory attributes of ice cream mostly depend on ice crystal size and % of fat. Ice cream is available in different flavors, forms. The demand of functional foods is growing rapidly all over the world due to increase in awareness of the consumers about the impact of food on health (Stoon, 2002). Therefore, one of the major recent challenges for dairy sector is to develop foods that may promote health and well being of individuals. In view of the raised attention of the nutritional value of foods and the increased popularity of functional foods, ice cream is a suitable matrix for added value in the nutrition area. Due to changing lifestyles, Individual are at a risk to diseases such as diabetes, hypertension, hyperlipidemia and atherosclerosis (Higurashi et al., 2007). Obesity affects more than 50% of adults and around one third of children in different countries and sugar and fat can increase the risk of obesity by increasing the energy density of the diet (Ruxton et al., 2010). Considering these facts, present 4

37 REVIEW OF LITERATURE investigation was planned to develop a product which can meet the demand of modern health conscious consumer. 2.1 HISTORY OF ICE CREAM Ice cream's origins are known to reach back as far as the second century B.C., although no specific date of origin nor has inventor been undisputable credited with its discovery. It originated in Europe and it was introduced later in the United States, where it developed into an industry. It is widely believed that ice cream evolved from iced beverage and water ices that were popular in the medieval period. Alexander the Great enjoyed snow and ice flavored with honey and nectar. During the Roman Empire, Nero Claudius Caesar (A.D ) frequently sent runners into the mountains for snow, which was then flavored with fruits and juices. In the 13 th century, Marco Polo returned to Italy from his famous journey to the orient and brought recipes for water ices said to have been used in Asia for thousands of years. The art of making these products then moved to France, Germany and England during the next few centuries. The first advertisement for ice cream in this country appeared in the New York Gazette on May 12, 1777, when confectioner Philip Lenzi announced that ice cream was available "almost every day. Around 1800, insulated ice houses were invented. Manufacturing ice cream soon became an industry in America, pioneered in 1851 by a Baltimore milk dealer named Jacob Fussell. Ice cream plant is also, established in New York, St. Louis, Chicago, Washington and Cincinnati. Ice cream production increased because of technological innovations, including steam power, mechanical refrigeration, the homogenizer, electric power and motors, packing machines, and new freezing processes and equipment. In 1846, Nancy Johnson patented a hand-cranked freezer that established the basic method of making ice cream still used today. In 1900, The Association of Ice Cream Manufacturers was formed and the later the name was changed to International Association of Ice Cream Manufacturers (IAICM). Development and acceptance of continuous freezers took place from The Vogt instant freezer was first introduced by Cherry Burrell and it was installed commercially in The Creamery package continuous freezer was introduced in Ice cream soda was introduced in 1879, while ice cream cone and Eskimo pie were introduced in 1904 and 1921 respectively. It was around 1920 that the value of ice cream as an essential food was generally recognized and the product has become 5

38 REVIEW OF LITERATURE immensely popular since then. The development of improved refrigeration and transportation, refrigeration units for home, improved packaging, marketing and high product standards have made ice cream widely available to the consumer. Modern automated operations on a large scale have enabled the industry to cater any kind of demand, for novelties, stick items, ice cream cakes, pies and other items. 2.2 ICE CREAM According to Food Safety and Standard Regulation (2011), Ice cream is the product obtained by freezing a pasteurized mix prepared from milk and/or other product derived from milk with or without the addition of nutritive sweetening agents, fruit, and fruit products, eggs and egg products, coffee, cocoa, chocolate, condiments, spices, ginger and nuts and it may also contain bakery products such as cake or cookies as a separate layer and/or coating. Nielson (1984) defined ice cream as a complex system consisting of foam which contains gas (air) dispersed as small air cells in a partially frozen continuous phase in which fat is dispersed as small air cells in a partially continuous phase, fat is dispersed as the inner phase in an emulsion. MSNF and stabilizers are in colloidal solution, while sugars and salts form a genuine solution. Ice cream (Glaces a la crème in French; Eiskrem in German; Helado in Spanish; Morozheno in Russian; Roomijs in Dutch; Fledies in Danish; Gelato in Italian; Sorvetes de crème in Portugese) is a frozen mixture. The mixture generally referred as ice cream mix is pasteurized and homogenized before freezing. Freezing involves rapid removal of heat while agitating vigorously results in incorporating air, thus imparting desirable smoothness and softness to the frozen product (Marshall et al., 2003). Khanna et al. (2004) defined as ice cream is a complex food colloidal made up of four phases of air (50%), ice (20%), fat (5%) and matrix (25%). 2.3 LEGAL STANDARDS OF ICE CREAM In India, according to FSSR (2011), frozen desserts means the product obtained by freezing a pasteurized mix prepared with milk fat and / or edible vegetable oils and fat having a melting point of not more than 37 C in combination and milk protein alone or in combination / or vegetable protein products singly or in combination with the addition of nutritive sweetening agents e.g. sugar, dextrose, fructose, liquid 6

39 REVIEW OF LITERATURE glucose, dried liquid glucose, maltodextrin, high maltose corn syrup, honey, fruit and fruit products, egg and egg products, coffee, chocolate, condiments, spices, ginger and nuts. The said product may also contain bakery products such as cake or cookies as a separate layer/ or coating, it may be frozen hard or frozen to a soft consistency. It shall have pleasant taste and flavor free from of flavor and rancidity and may contain food additives permitted. It shall also conform to requirements given in Table 2.1. It shall also conform to the microbiological requirements prescribed in Table 2.2. Table 2.1 FSSR requirements for ice cream and frozen dessert Requirements Regular Medium fat Low fat Total Solid 36% 30% 26% Wt. / Vol. (gms/l) Total Fat 10% >2.5 and <10% 2.5% Total Protein (N x 6.38) 3.5% 3.5% 3.0% On the basis of fat content, mainly four-grades of ice cream can be found usually in most market areas. One grade just meet the minimum fat content, often has over run that approaches the maximum allowed by law. At the other extreme, are the so called premium ice cream which are high in fat and low in over run. A third grade of ice cream designed, as a compromise between the minimum fat and premium product, is the type that has dominated the market for many years. And a fourth grade, often referred to as super premium ice cream, is characterized by higher fat content and lower overrun than premium varieties. Representative formulae for these grades have been suggested in Table 2.3 (Kilara, 1993). 7

40 REVIEW OF LITERATURE Table 2.2 Microbiological standards for ice cream Microbiological parameters Total plate count Coliform count Requirement Min. 2,00,000/g Max. 2,50,000/g Min. 50/g Max. 100/g E. Coli Absent/g Salmonella Absent/25g Staphylococcus aureus Less than 10/g Yeast and Mold count Less than 10/g Spore count Listeria monocytogenes Absent/g Absent/g Table 2.3 Representative formulae for ice cream of different grades Grade of Ice cream Constituents Minimum Standards (%) Regular (%) Premium-1 (%) Premium-2 (%) Super Premium (%) Milk fat Milk solids not fat Whey solids Sucrose Corn syrup solids High fructose solids Stabilizer Emulsifier Total solids (Kilara, 1993) 8

41 REVIEW OF LITERATURE 2.4 ICE CREAM MARKET India is the largest milk producer across the globe and it accounts for one-fifth of the total global milk production. The Indian ice cream sector is a competitive market with strong competition from the unorganized sector. The global sales of dairy products in 2002 were $US 43.7 bn (Thomas and Elphinstone, 2003). Overall global market is static, but volumes are falling in Western Europe, Japan and Latin America, and on the increase in Eastern Europe, Asia Pacifia and Asia. Ice cream industry in India has grown considerably over the last few years. Total domestic market is estimated at about Rs. 21,000 millions, out of which the GCMMF now account for nearly 37% market share followed by Unilever and Mother Dairy (Saxena, 2007). The year on year growth of the ice cream has been consistently at about 15% by volume and 20% by value over the last few years. Indian ice cream market is about 350 million liters per annum valued at about 21,000 million of which about 65% is with the organized sector. The per capita annual consumption of ice cream is still at 0.25 litres as against nearly 12 litres of the USA (Saxena, 2007). That is consumption of ice cream per capita per annum in India is still the lowest in the world. The percentage market share of different ice cream brands in India is given below (Table 2.4). Table 2.4 The percentage market share of different ice cream brands in India Company % Market shared Amul 38 Kawality waals 14 Vadilal 12 Mother Dairy 8 Cream bell 6 Others 22 9

42 REVIEW OF LITERATURE 2.5 LOW FAT ICE CREAM Excessive intake of high fat products has been associated with increased risk of obesity, certain forms of cancer, high blood cholesterol, diabetes and coronary heart diseases. Consumption of low-fat or non-fat dairy products has increased in recent years due to potential health benefits and nutritional advantages (Yackel and Cox 1992). Lombard (1965) prepared ice cream containing 32% total solids (5% fat, 12.1% milk SNF, 14% sugar, 0.9% stabilizer, emulsifier and 0.05% CaSO 4 ). A market survey in the U.S.A also confirmed a strong interest in low calorie frozen desserts and ice cream but indicated that the existing products of this type have a poor flavour and texture. Reducing intake of dietary fat and cholesterol is rapidly becoming an obsession among national health groups. The Dairy Council of California urges the entire dairy industry to shape new nutrition recommendation based on low fat products (Carson and Kubena, 1988). However, the retention of organoleptic characteristics in low-fat products is difficult, and they faced a lot of challenges in maintaining quality of low-food products (Duxbury, 1991). The primary difficulties to be overcome in low-fat or fat-free products are - to maintain the quality of texture and flavour intensity. Texture quality has been addressed with some achievements using fat mimetic but flavour is not so easily solved (Hatchwell, 1994). According to Nutritional Labeling and Education Act (NLEA), frozen desserts can now be labeled Reduced fat if the reformulated product contain 25 percent less fat than the original formulation. The term Lite/Light can be used if a 50 per cent reduction of calorie is achieved. A product can be labeled Low fat if one serving of the food contains no more than 3 grams of fat and food may be labeled as Fat free if it contains less than 0.5 grams of fat per serving. Serving sizes are defined and an average serving size for ice cream and frozen desserts is ml (Kilara, 1998). 2.6 FRUIT ICE CREAM The growing interest in the study of natural antioxidant compounds has been accompanied by an increase in the market presence of what are known as functional foods or nutraceuticals or health foods. Addition of fruit preparations, fruit flavours, and fruit purees has enhanced versatility of flavour, texture, colour, variety to Ice cream and additionally fruits also have a healthy image. India is the second largest fruit producing country in the world after China (FAO). Ice cream available commercially is generally poor in natural antioxidants like vitamin C, 10