EFFECT OF HURDLE TECHNOLOGY ON BITTERNESS AND SHELF LIFE OF SWEET ORANGE (Citrus sinensis.L) JUICE
KrishiKosh
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Title |
EFFECT OF HURDLE TECHNOLOGY ON BITTERNESS AND SHELF LIFE OF SWEET ORANGE (Citrus sinensis.L) JUICE
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Creator |
RHODA SUSESHI, P
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Contributor |
UMA DEVI, K
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Subject |
fruits, confectionery, fruit juices, flavouring, storage, sugar, sampling, acidity, biological phenomena, vitamins
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Description |
Citrus fruits are recognized as an important component of the human diet providing a variety of constituents important to human nutrition including vitamin C, folic acid, potassium, flavonoids, pectin and dietary fiber, in addition to energy. Citrus also contain significant amount of highly oxygenated terepenoid compounds (Limonoids), particularly in underutilized by products of citrus juice production. The sweet orange (Citrus sinensis L. Osbeck.) belongs to citrus fruits which contributes 71% of the total citrus production in the world. India ranks 3rd in the production of sweet orange with annual production of 4266.9 million tonnes. Fresh juice of sweet orange is an important nutritious product providing 45 kcal, moderate quantity of vitamin C, potassium, bioflavonoid and folic acid and essential nutrients. It is refreshing, thirst quenching and energizing drink that improves health and meets nutritional requirements (Syed, 2012). Fresh juice is highly appreciated as a part of breakfast, mid morning, noon and evening beverages in all seasons, especially during summer. The major problem in citrus industry is the formation of bitterness in the citrus juice within hours of juice extraction from the fruit or if heated within a few minutes. This is called “delayed bitterness”. The primary causes of delayed bitterness are the triterpenoid dilactones, limonin and nomilin. The study, “Effect of hurdle technology on bitterness and shelf life of sweet orange (citrus sinensis.L) juice” was planned with an objective to reduce the bitterness and extend the shelf life of sweet orange juice in its fresh plain form, retaining its natural taste and flavour. Hurdle technology in this work is a method of ensuring that changes in sweet orange juice are eliminated or controlled so that the juice is safe for consumption, and its shelf life is extended. The hurdles in a food system are high temperature during processing, low temperature during storage, increasing the acidity, lowering the water activity and addition of sugar, salt or preservatives. To delay formation of bitterness and retain the fresh flavour, taste and mild acidity of the fresh sweet orange juice for a period of few hours at ambient temperature to a few days at low temperatures, small quantities of sugar, salt and preservative were added separately and tested for acceptability and physic chemical and microbial characteristics. Irradiation was another hurdle used on plain sweet orange juice and on samples added with sugar or salt packed in two materials, HDPE pouches and glass bottles and subjected to four doses of irradiation, 0.25, 0.50, 0.75 and 1.00kGy. Samples were analyzed for physicochemical properties (pH, TSS, titrable acidity, reducing sugars and vitamin C,) and microbial tests. Sensory evaluation was done using hedonic scale with 5 point continuum for evaluating the acceptability by taste panel judges. Sweet orange juice was packed in HDPE pouches in six different formulatins i.e., T1 (plain sweet orange juice), T2 (plain sweet orange juice + sugar), T3 (plain sweet orange juice + salt), T4 (plain sweet orange juice + potassium sorbate), T5 (plain sweet orange juice + sugar + potassium sorbate), T6 (plain sweet orange juice + salt + potassium sorbate).These samples were stored at ambient temperature, at 6-9°C and at - 20°C. Sensory evaluation of samples kept at ambient temperature and at 6-9°C tested every two hours to estimate at which hour the bitterness has developed showed that at ambient temperature bitterness developed at 5th hour after squeezing the juice and at 9th hour in juice stored at 6-9°C. Physicochemical analysis of sweet orange juice samples with hurdle materials, sugar, salt, preservative before and after irradiation at four doses showed that the pH of the juice decreased in both HDPE pouches and glass bottles. The titrable acidity did not change due to the effect of the irradiation doses. There was a slight increase and decrease in the acidity values. The increase and the decrease in the acidity values were statistically not significant. There was a slight decrease in the reducing sugars but the decrease was statistically not significant. There was very slight decrease in the Vitamin C as the irradiation dose increased to 0.5kGy; 0.75kGy and 1.00kGy. The juice kept in HDPE pouches and stored at -20°C and studied for shelf life for 15 days with an interval of 5 days revealed that, pH of the sweet orange juice decreased as the storage period increased from 0th day to 15th day. TSS of sweet orange juice samples with and with hurdle materials gradually increased from 0th day to 15th day. The increase was significant (P |
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Date |
2016-06-22T15:03:11Z
2016-06-22T15:03:11Z 2013 |
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Type |
Thesis
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Identifier |
http://krishikosh.egranth.ac.in/handle/1/67740
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Language |
en
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Relation |
D9432;
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Format |
application/pdf
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Publisher |
ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY
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