Biochemical changes and quality characterization of cold-stored ‘Sahebi’ grape in response to postharvest application of GABA

• Published in: Food chemistry 2022-03, Vol.373 (Pt A), p.131401-131401, Article 131401
• Main Authors: Asgarian, Zahra Sadat, Karimi, Rouhollah, Ghabooli, Mehdi, Maleki, Masoomeh
• Format: Article
• Language: English
• Subjects: Anthocyanidins; Antioxidants; Ascorbate Peroxidases; Cold Temperature; Flavonoids; Food Storage; Fruit; gamma-Aminobutyric Acid - pharmacology; Grape; Postharvest; Tartaric acid; Vitis; γ-Aminobutyric acid
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2021.131401

•GABA maintained postharvest quality and increased chilling tolerance of ‘Sahebi’ grape.•GABA retards rachis browning and weight loss by triggering ABA content.•Berry soluble sugars and organic acids retained at higher level.•GABA preserved grape phenolic acids, stilbenes, flavonoids and anthocyanidins but drops PPO activity.•GABA enhances antioxidant enzyme activity, DPPH and FRAP scavenging capacity and mitigates lipid peroxidation. In this study, the effect of γ-aminobutyric acid (GABA) at 0 (control), 20 and 40 mM on maintaining postharvest quality, chilling tolerance and fungal decay of ‘Sahebi’ grapevine (Vitis vinifera L.) was investigated during 60 days storage at 1 °C. GABA-treated fruits especially at 40 mM showed less weight loss (35%), rachis browning (30%) and decay incident (63%) compared to the control. GABA-induced abscisic acid was linked to lower membrane electrolyte leakage (13%) in treated grapes. Moreover, at the end of 60 days, GABA treatment at 40 mM resulted in higher activities of antioxidant enzymes including superoxide dismutase (50%), catalase (35%), guaiacol peroxidase (65%), and ascorbate peroxidase (47%) and lower malondialdehyde (21%) compared to control samples. The highest soluble sugars and organic acids were related to 40 mM GABA-treated grape clusters. Phenolic compounds (phenolic acids, stilbenes, flavonoids and anthocyanidins) and antioxidant capacity increased in 40 mM GABA-treated grape due to lower polyphenol oxidase activity. Therefore, GABA is recommended for maintaining internal quality and reduction in fungal decay and chilling injury of grapes during postharvest storage.