PHYSIO-CHEMICAL CHANGES DURING RIPENING IN WILLIAMS, ZELING AND GRAND NAIN BANANA

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1 J. Dairying, Foods & H.S., 28 (3-4) : , 2009 AGRICULTURAL RESEARCH COMMUNICATION CENTRE / indianjournals.com PHYSIO-CHEMICAL CHANGES DURING RIPENING IN WILLIAMS, ZELING AND GRAND NAIN BANANA S.C. Sarode 1 and N.H. Tayade 2 Faculty of Agric. Engg., Indira Gandhi Krishi Vishwa Vidyala, Raipur. ABSTRACT The banana cultivars viz. Williams, Zeling and Grand Nain were packed in polyethylene bags with ventilation and stored at room temperature (32 ± 2 0 C),cold storage (20 ± 2 0 C) and deep freezer (4 ± 2 0 C).Changes in storage characteristics were recorded at 3 days intervals till the condition of fruit turned to rejectable stage. For chemical analysis, pulp of each sample was ground in grinder (mixer). Known amount of these samples were weighed for determining ph, TSS, Moisture and Total sugar. The ph value of banana fruit decreased as storage period increase. There was increase in TSS, moisture and total sugar as increase in storage period increase. At 4 0 C, due to occurrence of chilling injury in samples, there was negligible amount of sugar present after 12 days storage. Room temperature can control the banana quality upto 21 days while for 20 0 C, quality of banana could K controlled upto 39 days. Key words : ph, TSS, Moisture, Total sugar, Banana. INTRODUCTION Banana (Musa sp) is one of the oldest fruit known to mankind. It belongs to the family Musaceae and botanically named Musa paradisiaca. The word banana was applied to all table varieties. Formerly, the word banana was applied to Nendran banana of Kerala which was however called Plantain by westenners. Bananas are cultivated in over 100 countries. They are grown over a harvested area of 10 million ha with an annual production of around 88 million metric tones in The fruits are normally dispatched to the market immediately after harvesting and they ripen on their way to the destination. The field temperature reaches upto 45 0 C in most part of India during summer as a result burn injury occurs on fruits. On the other hand, particularly during winter season, the atmospheric temperature drops below 10 0 C in the Northern hilly and plain area. The temperature attained by the fruits during transit could vary from 10 0 C to 37 0 C, with the result there are variations in quality of ripe banana (Ranganna, 1992). 1 Deptt. of Agri. Engg. College of Agriculture. Saralgaon , India. 2 Shri Shivaji College f Horiculture, Amravati , India. Green unripe Robusta banana fruits at two stages of maturity (100 and 115 days from fruit set) were held at room temperature (control) and at 15 and 20 0 C for 1-4 weeks, followed by ripening in ambient conditions. The fruits remained green, firm and unripe for 2-3 weeks at all temperatures. The delay in ripening was related to reduce rates of softening and peel colour development and to increased pulp/peel ratio. Quality of fruits after 1-4 weeks of holding at 20 0 C was best, quality was also best in fruits held for 3 weeks at 15 0 C by harvesting fruits early(at 100 days) the shelf life in ambient conditions were extended from days (Krishanamurthy,1989). Temperature plays an important role in ripening process of banana and the development of optimum quality. The efficiency of four post harvest treatments of the bunches of banana fruits (Gibberellic acid at 150 ppm + 6 per cent Waxol, Gibberellic acid at 150 ppm + Benlate at 500ppm,use of an ethylene absorbent and wrapping with polythylene) was evaluated under ambient

2 Vol. 28, No. 3/4, temperatures. The three treatments were found beneficial in retarding the ripening process and extending ripening by 3,2 and 1 days respectively. These treatments resulted in relatively high numbers of green fruits, good marketability over a long period and reduced weight loss. The metabolic rate of the treated fruit was low, as evidenced by low catalase activity in pulp tissue. Wrapping the bunches in polythyelene film was effective in minimizing the weight loss and bruising (Rao and Chudawat,1988). To get banana fruit with good consumer acceptability and longer shelf life, it is imperative to determine storage characteristic of banana at different temperatures. MATERIAL AND METHOD The available banana cultivars viz. Williams, Zeling and Grand Nain were selected for the study. The study was carried out in the Faculty of Agricultural Enginerraing, Indira Gandhi Vishwa Vidyala, Raipur during Bunches of these three cultivars of uniform size were harvested from keptive farm of Jain Foods Ltd. Jalgaon about 105 days after fruits set. Each fruit without any blemishes were cut from the bunches. Three lots were made from each variety. Banana fruits were packed in polyethylene bags (22.5 mm x 15mm and 40 micron thickness) with ventilation, having three samples of each variety in one bag. One lot from each variety was kept at room temperature (32 ± 2 0 C), cold storage (20 ± 2 0 C) and deep freezer (4 ± 2 0 C).Changes in physiological characteristics like Physiological loss in weight (PLW), PLW/ initial weight ratio and pulp/peel ratio were recorded at 3 days interval. Observations were recorded till the rejectable condition of fruit. One sample from each variety was taken out for analysis, therefore total 9 samples viz. 3 from room temperature, 3 from cold storage and 3 from deep freezer were taken out. Parkin and scott (1979) placed banana bunches in polyethylene sleeves tied at both ends markedly retarded ripening and at 20 0 C, fruits were held for 50 days. Ripening was further delayed by including an inert carrier such as vermiculite, coke or pumice impregnated with a strong solution of potassium permanganate. Elzayat (1996) investigated the effect of pretreatment (Dipping in thiabendazole at 400 ppm), storage temperature (15 0 C) and packing (wrapping in polyethyelne before packing in cartons) on the storage quality of banana cv. Maghrabi (green fruits harvested at three quarter stage from Kanater experiment station, Egypt) in 1992 and Fruits were stored for one month. All packaged fruits were in good condition after storage and had a shelf life 5 to 7 days in ambient conditions. RESULT AND DISCUSSION The relationship between dependent variable (ph, TSS, Moisture and total sugar) and independent variable (storage days) variables is given in Table 1. ph : Comparison of changes in ph of banana when stored at various temperatures against storage days for various varieties of banana was shown in Fig 1. The ph of banana fruit decreased with the increase in storage duration in all varieties at all temperatures viz, 32, 20 and 4 0 C. This may be due to as ripening Fig. 1. Changes in ph against storage days for various varieties of banana.

3 222 J. DAIRYING, FOODS & H.S. advances, acidity increases which resulted in decrease of ph. Similar results were reported by Lodh et al. (1971) and Madamba et al. (1977). During 30 days of storage at 32 0 C, for all varieties of banana, the initial range of ph was from 4.76 to 4.87 while at 20 0 C, it was from 5.10 to 5.12, which decreased in the range of 4.81 to 4.86 during 39 days of storage. At 4 0 C, ph value fell from to during 30 days of storage. The relationship between ph and storage days was found to be linear upon regression analysis for all samples. The high value of coefficient of correlation R 2 (0.98 to 0.99) indicated that there exist a high degree of relationship between dependent (ph) and independent (storage days) variables. TSS : Comparison of changes in total soluble solids (TSS) against storage days for various varieties of banana stored at various temperatures was shown in Fig 2. In general, TSS of banana fruits increased with the increase in storage duration in all varieties at 32, 20 and 4 0 C. This may be due to conversion of complex polymers into simple substance. Fig. 2. Changes in TSS against storage days for various varieties of banana. Table 1. Mean haemoglobin levels in adult rats (N= 8) 0 C V Equations Equaions Equations Equations (ph) (TSS) (Moisture) (Total Sugar) 32 W Y= X Y= X Y= X Y= X (R 2 =0.99) (R 2 =0.94) (R 2 =0.99) (R 2 =0.63) Z Y= X Y= X Y= X Y= X (R 2 =0.98) (R 2 =0.97) (R 2 =0.90) (R 2 =0.62) G Y= X Y= X Y= X Y= X (R 2 =0.99) (R 2 =0.97) (R 2 =0.89) (R 2 =0.60) 20 W Y= X Y= X Y= X Y= X (R 2 =0.98) (R 2 =0.90) (R 2 =0.97) (R 2 =0.87) Z Y= X Y= X Y= X Y= X (R 2 =0.99) (R 2 =0.89) (R 2 =0.97) (R 2 =0.80) G Y= X Y= X Y= X Y= X (R 2 =0.98 (R 2 =0.89) (R 2 =0.99) (R 2 =0.82) 4 X Y= X Y= X Y= X Y= X (R 2 =0.99) (R 2 =0.56) (R 2 =0.97) (R 2 =0.80) Z Y= X Y= X Y= X Y= X (R 2 =0.98) (R 2 =0.42) (R 2 =0.97) (R 2 =0.81) G Y= X Y= X Y= X Y= X (R 2 =0.99) (R 2 =0.53) (R 2 =0.95) (R 2 =0.80)

4 Vol. 28, No. 3/4, Fig. 3. Changes in Moisture percentage against storage days for various varieties of banana. For 32 0 C storage, the increase in TSS was negligible upto 9 days but then it acquired appreciable increase while at 20 0 C storage, the increase of TSS was significant upto 24 days then it suddenly shooted up. In contrast to above, for 4 0 C, the value of TSS decreased after 21 days of storage possibly because of decomposition of carbohydrates into CO 2 and H 2 O.These result are in agreement with the finding of Madamba et al (1977). The relationship between TSS and storage days was found to be linear upon regression analysis for samples kept at 32 and 20 0 C. The high value of coefficient of correlation R 2 (0.89 to 0.99) indicated that there exist a high degree of relationship between dependent (TSS) and independent (storage days) variables. For 4 0 C, value of coefficient of correlation R 2 (0.42 to 0.53) indicated that there exist a moderate degree of relationship between dependent (TSS) and independent (storage days) variables. Moisture : Of all the factor which affects the quality of banana, moisture content probably the most important. Comparison of changes in moisture of banana when stored at various temperatures against storage days for all varieties was shown in Fig 3. Moisture of banana fruit increased with the increase in storage duration in all varieties. This may be due to movement of water from peel to pulp. There was sudden rise in moisture percentage after 21days of storage at 32 0 C.This is because of high temperature might have caused almost total transfer of moisture from peel to pulp thereby deterioration of banana fruit and fruit becoming pulpy. During storage at 20 0 C, banana fruits showed uniform increase in moisture percentage (71 to 77) which was suitable for ripening. At 4 0 C, due to occurrence of chilling injury, the fruit became black and watery as a result of increase in moisture percentage during storage. Similar results were reported by Awan and Ndubizu (1978) however, the result was not in agreement with the finding of Bose and Mitra (1990) who reported that fruit moisture percentage remained approximately constant for 27 days at room temperature and 45 days at cold storage (13 0 C). The relationship between moisture percentage and storage days was found to be linear upon regression analysis for all samples. The high value Fig. 4. Changes in Total sugar percentage against storage days for various varieties of banana.

5 224 J. DAIRYING, FOODS & H.S. of coefficient of correlation R 2 (0.89 to 0.99) indicated that there exist a high degree of relationship between dependent (moisture percentage) and independent (storage days) variables. Total sugar : Comparison of changes in total sugar of banana when stored at various temperatures against storage days for various varieties of banana was shown in Fig 4. There was increase in total sugar percentage as ripening advanced in all varieties during storage at 32, 20 and 4 0 C.This may be due to conversion of starch into sugar. During 32 0 C storage, there was decrease in total sugar percentage after 24 days due to deterioration of fruit. During storage at 20 0 C, total sugar percentage remained approximately same for Williams, Zeling and Grand Nain up to 21 days of storage. This is possibly due to slow progress in ripening of fruit. Afterwards, sudden rise in total sugar percentage was noticed which is because of progress in ripening of fruits. At 4 0 C, there was increase in total sugar percentage only upto 12 days of storage. Afterwards, there was negligible amount of sugar present in sample which could not be traceable in titration. There may be breakdown of sugar into alcohol due to fermentation. These results are in agreements with the findings of Aziz et al (1976). Carvalho et al.(1990) wrapped banana fruits in low density polyethylene bags and fruits which had not been wrapped were stored at ambient condition at 20 0 C. Total sugars increased from per cent in green fruits to per cent during ripening. The maximum amount of sugar was found in samples of all varieties during storage at 20 0 C. Therefore, 20 0 C is a most suitable temperature for storage of banana as compared to 32 and 4 0 C. Hence, 20 0 C storage temperature can be strongly recommended for storage of all varieties of banana in general and Williams, Zeling and Grand Nain varieties in particular. According to Nagaraju and Reddy (1955) the rate of increase in total sugars and decrease in starch were slow in fruits stored in cool chamber compared with those in ambient conditions. The relationship between total sugar and storage days was found to be linear upon regression analysis for all samples kept at 32 and 20 0 C. The high value of coefficient of correlation R 2 (0.60 to 0.87) indicated that there existed a high degree of relationship between dependent (total sugar percentage) and independent (storage days) variables.. For 4 0 C, value of coefficient of correlation R 2 (0.80 to 0.81) indicated that there existed a high degree of relationship between dependent (total sugar percentage) and independent (storage days) variables. REFERENCES Awan, J. A. and Ndubizu, T.O.C. (1978) Some aspects of nutrients changes in stored plantain fruits. Paradisiaca. No.3: Aziz, A. B. A., (1976) Egyptian J. Horti. 3(1): Bose, T.K. and Mitra, S.K. (1990) Fruits, Tropical and sub tropical. Nayaprakash, First edition, Calcutta. pp Carvalho, H. A. and A.B. Chitarra. (1990) Horti. Abstract. 60(12):1185. Elzayat, H. E. (1996) Bull. faculty Agril. Univ. of Cairo. 47(2): Krishanamaurthy, S. (1989) J. Food Sci. 29(1): Lodh, S.B.; et al. (1971) Indian J. Horti. 28: Madamba, L.S.; et al. (1977) Food Chemi., 2(3): Nagaraju, C.G. and Reddy, T.V. (1995) Adv. Horti. Sci. 9(4): Parkin, R. and Scott, K.J. (1979) Agril. Gezette of New South Wales. 90(5):52. Ranganna, S. (1992). Handbook of Analysis and Quality Control for Fruit and Vegetables Products. IInd edition. Tata McGraw-Hill publishing company Ltd.New Delhi. Rao, D.V. and Chudawat B. S. (1988) Guj. Agri. Uni. Res. J. 14(1):42-48.