Quality of Rubi grapes coated with Aloe vera L. gel in the pre-harvest

Abstract

The use of edible coatings is one of the technologies that has been studied for the maintenance of post-harvest quality of fruits; they can function as a barrier for water loss, change gas exchange, and improve fruit appearance. Aloe vera gel, which is rich in polysaccharides, is one of the of coatings that has been tested for this purpose. In this context, the objective of this work was to evaluate the effect of pre-harvest application of A. vera gel in the post-harvest quality of Rubi grapes. The treatments used were: A. vera gel at the rates of 100, 200, and 300 mL L-1, chitosan (160 g L-1), and distilled water (control). The following post-harvest characteristics were evaluated: Titratable acidity (TA), soluble solid (SS) contents, SS/TA, color indexes (brightness, hue, and chroma), and anthocyanin contents. The coatings with Aloe vera gel L. improved the post-harvest quality of Rubi grapes, by decreasing titratable acidity, increasing SS/TA, and improving color indexes. The coatings also increased anthocyanin contents. Thus, the use Aloe vera gel is recommended for the coating of Rubi grapes in the pre-harvest period.