Overall Quality Properties of Kiwifruit Treated by Cinnamaldehyde and Citral: Microbial, Antioxidant Capacity during Cold Storage.

This work was undertaken to evaluate the microbiological characteristics and antioxidant and physiological activities in kiwifruits (Actinida deliciosa var. Qinmei) with/without cinnamaldehyde (C1) and citral (C2) fumigation treatments (5 μL/L) during 0, 3, 6, 9, and 12 d of storage at 4 °C. Essential oils (EOs) treatment lowered the total viable counts, yeast, and mold to 1.54, 2.36, and 2.05 log CFU/g, respectively. Moreover, EOs improved the antioxidant activities of kiwifruit. They enhanced phenolics and flavonoids content in fruit tissue by 49.48% at day 3 and 56.93% at day 6, respectively. In addition, ascorbic acid in treated groups had the lower losing rate. Similarly, MDA (malondialdehyde), H2 O2 (hydrogen peroxide), and • O2- (superoxide anion) production were effectively decreased in the range of 27.27% to 54.38%. Physicochemical characteristics showed that kiwifruits from treated group maintained higher levels of flesh luminosity and firmness. EOs also decreased the levels of reducing sugar by 45.97% at day 3, and increased the content of soluble protein and hydrolyzed amino acid. Therefore, postharvest EOs treatment has positive effects on delaying senescence and enhancing antioxidant capacities in kiwifruit.