Effect of Bio-Based Protein Coating on the Quality and Shelf Life of Fig Fruit (Ficus Carica L.)

Fruit coatings are an appropriate method to preserve quality and extend the shelf life of fruit. This study focused on the impact of coating fig fruit with bio-based proteins (sunflower seeds, whey, and caseins). The fruits were dipped into the coating solution and dried. Then, the fruits were stored in the refrigerator at 5°C with 85–90% relative humidity. Fruit quality was higher by using the coating method, and the fruits showed significantly higher sensory evaluation scores (color, texture, brightness, and overall acceptability) compared to the control, while the highest score was in the whey protein coating treatment. The weight loss and total soluble solids (TSS) in all coated fruits were significantly lower compared to the control. In particular, sunflower seeds protein had the highest titratable acidity (TA), and whey protein reduced polyphenol oxidase activity than the other treatments. However, a prolonged storage period substantially increased weight loss, TSS, TA, total sugar, and total phenol, as well as reduced all sensory evaluation scores. Therefore, the data of this study help to prolong the fig fruit shelf life and the period of display in the market. Especially, all bio-based protein coating significantly reduced fresh weight loss and preserved the fruit quality than the control throughout the post-harvest.