Shelf-Life Investigation of Whey Protein Concentrate-Rice Bran Oil Coated Kiwifruit (Actinidia deliciosa)

Edible coating can provide effective protection for fresh fruits. In the present paper we use an edible coating based on whey protein concentrate (WPC) and four different levels of rice bran oil (0, 0.2, 0.4, and 0.6 g/100ml) to maintain the quality of kiwifruit (A. deliciosa). We have tested and compared the following postharvest storage quality conditions of coated groups and a control group in four subsequent weeks: weight loss, color parameters (L*, a*, b*), texture changes, titratable acidity, soluble solids content, and sensory attributes. Coating application reduced the weight loss in kiwifruits. Our results indicate also a significant difference in the soluble solids content and a non-significant difference in titratable acidity between the control and coated kiwifruits after 4 weeks of storage at 8°C. Moreover, our results show that kiwifruits coated with whey protein concentrate-based coatings had higher L*, and lower a* than the uncoated kiwifruits. Our coated kiwifruits received higher scores than the control samples in sensory evaluations. Coating reduced texture loss up to 5% with respect to the control samples depending on the rice bran oil contents.