44C-12 |
Characterization of cloud components from selected tropical fruits |
E. K. KOFFI, Food Science and Technology, University of Georgia, Athens, GA 30602-7610 and L. Wicker. Whey proteins have the potential to improve the nutritional value of tropical fruit juices through fortification. However, previous work indicates that there is still great potential for improving the acceptability of the fortified beverages. The pectin and protein structure of cloud in insoluble cloud matter (ICM) or alcohol insoluble solids (AIS) will likely influence cloud stability of fruit added whey beverages. The objective of this study is to evaluate the composition of banana and mango for factors that are likely to influence cloud stability compare to citrus. The ICM was obtained after centrifugation (three times) of the fruit pulps at 21000g for 15 minutes, followed by washing in distilled water after each cycle. The AIS was obtained after washing the fruit pulp with 95% alcohol three times and a final wash with acetone. The methoxylester and the anhydrogalacturonic acid contents were determined colorimetrically. Proteins were characterized by SDS-PAGE using the Phastsystem. Mango had the highest methoxylester content (89%) followed by orange (87%) and banana (69%). The anhydrogalacturonic acid was the highest in mango (6.3%), followed by orange (5.6%) and banana (4.5%). Protein fractions of 14,000 to 60,000 molecular weight were identified in banana AIS whereas those in the ICM ranged from 14,000 to 40,000. In mango AIS the protein fractions ranged from 14,000 to 90,000 whereas the range was from 14,000 to 30,000 in the ICM. Tropical fruits contain various amounts of pulp-associated compounds that could have a major impact on the stability of the juices derived from them. Knowledge about the composition of mango and banana will help predict the performance of such fruits in producing cloud stable whey fortified beverages. Results of this study will help prevent the loss of 40% of the overripe fruits in developing countries.
Session 44C, Fruit & Vegetable Products: Chemistry
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