45F-18 |
Different grading methods affect blueberry quality and shelf life during refrigerated storage |
Y. LU, J. L. Silva, and T. Kim. Dept. of Food Science & Technology, Mississippi State Univ., Campus Mailstop 9805, Mississippi State, MS 39762-9805 With increased demand for high quality, fresh fruits and vegetables, automatic grading is needed to increase production while lowering operating costs. However, this may affect the post-harvest quality and shelf life of blueberries. The objective of this research was to determine the quality and spoilage rate and causes of non-graded, hand or machine graded rabbiteye blueberries (Vaccinium ashei). The pH, titratable acidity (TA), soluble solids (Brix), soluble solids to acid ratio (STA), and surface color of non-graded, hand graded, and machine graded blueberries were determined. Aerobic plate counts (APC), yeast and mold counts (YMC), weight loss, and rate of spoilage were determined during storage at 4oC. Hand graded berries had higher pH and non-graded berries had higher Brix, but they were not different in TA and STA. There was no difference in APC between grading methods, but they differed in YMC during storage. Machine graded berries' YMC increased at a faster rate than in the other grading methods. The YMC were higher for machine graded berries after 8 d but were similar to non-graded berries after 12 d. The rate of spoiled berries rapidly increased during the first eight days, with a lower rate of increase the next four days. Machine graded berries had a higher spoilage rate than the other berries. The increased spoilage rate of machine graded berries was probably caused by handling damage, increasing the number of leakers and broken berries, and not by bacteria, or yeasts and molds.
Session 45F, Fruit & Vegetable Products: Fruits (Fresh)
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