Ascorbic Acid Content in ‘Passe-Crassane’ Winter Pear as Affected by 1-Methylcyclopropene during Cold Storage and Shelf Life

Abstract

<jats:p>‘Passe-Crassane’ is a winter pear which requires a cold storage period to produce ethylene and properly ripen. In this study, the effects of 1-methylcyclopropene (1-MCP), an ethylene perception inhibitor, were studied during cold storage (30, 60, 90, and 135 days) and shelf life at 20 °C (30 days) of ‘Passe-Crassane’ pears. Ethylene accumulation was monitored and quality parameters were measured. Oxidative stress of fruit was estimated by measuring lipid peroxidation. The cell antioxidant status was assayed determining ascorbic acid (AsA) content and the activities of the enzymes ascorbate peroxidase (APX), monodehyroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) involved in its oxidation and recycling. AsA content was positively affected by higher temperature (20 °C) and by 1-MCP after 90 days of storage. This effect was more evident after shelf life. Thiobarbituric acid reactive substances (TBARS) increased in pears kept at 20 °C and in treated pears, starting from 60 days of cold storage and remained elevated after shelf life. Although during storage 1-MCP enhanced the activities of APX and DHAR only at 90 days, after shelf life the effect on APX, MDHAR, and DHAR activities was more pronounced and enzyme activities were higher in treated pears sampled after 60 and 90 days of storage. The results indicate that 1-MCP has a beneficial effect on the antioxidant potential of winter pears: it maintained high AsA levels throughout storage and shelf life and improved the enzymatic mechanisms of AsA recycling, especially after shelf life. The effect of 1-MCP on pear ripening may not be solely due to its action on ethylene but also to an increase in antioxidant defense. A stress response linked to lipid peroxidation is triggered by the interaction of cold temperatures and treatment as ‘Passe-Crassane’ pears acquires ripening competence. However, it may be compensated by the high AsA content.</jats:p>

Effect of Temperature and 1-Methylciclopropene on the Storability of ‘Alexander Lucas’ Pear

“…Franck et al (2003) noticed that browning inducing CA storage conditions in 'Conference' pear resulted in more than 4-fold faster decrease in ascorbic acid concentration. Cocetta, Mignani, and Spinardi (2016) found that treatment of 'Passe Crassane' pear with 400 nL L -1 1-MCP maintained a higher ascorbic acid during air storage at 0 °C and during shelf life. The effect of 1-MCP on pear seems to be similar to apple.…”

Ethylene: Management and breeding for postharvest quality in vegetable crops. A review

“…Also, selenium treatments were effective in repressing the expression of ET biosynthetic genes, and in stimulating the enzymatic antioxidant systems in tomato, while prolonging the shelf life ( Zhu et al., 2017 ). Another widely used product, 1-MCP can have different effects on the quality attributes of climacteric fruits like tomatoes ( Poyesh et al., 2018 ; Zou et al., 2018 ; Taye et al., 2019 ) pears ( Cocetta et al., 2016 ), apples ( Kim et al., 2018 ) and bananas ( Satekge and Magwaza, 2020 ). On the other hand, it has been reported to have just slight effects on internal fruit quality of non-climacteric fruits ( Li et al., 2016 ).…”