Abstract
The postharvest life of flat peach fruit is limited by the appearance of chilling injury symptoms, especially internal browning. In this study, impacts of the exogenous application of proline (0, 5, 10, and 15 mM) and L-cysteine (0, 0.2, 0.4 and 0.6%) on attenuating chilling injury of flat peach fruit were evaluated all over the cold storage. The results demonstrated that the fruits treated with 15 mM proline and 0.4 % L-cysteine showed lower levels of internal browning and these treatments prevented the excess enhancement of total soluble solids (TSS), the decline of titratable acidity (TA) content and the loss of fruit firmness during storage time. A lower accumulation of hydrogen peroxide (H2O2), malondialdehyde (MDA), electrolyte leakage, and higher activity of antioxidant enzymes, along with higher ascorbic acid content and antioxidant capacity, were observed in treated fruits. Treated fruits also showed higher activity of phenylalanine ammonia lyase (PAL) and conversely lower activity of polyphenol oxidase (PPO), which led to a higher accumulation of total phenols and flavonoids. Moreover, a higher accumulation of endogenous proline was observed in 15 mM proline treated fruits. Eventually, according to our results, the exogenous administration of proline and L-cysteine as safe, natural and environmentally friendly treatments, preserved the nutritional quality of flat peach fruits during long-term cold storage.
Highlights
The flat peach (Prunus persica (L.) Batsch ‘Maleki’) as a mutation of the standard peach, has high economic value due to excellent texture and taste and being a unique source of phenolic compounds such as flavonoids, anthocyanin, and so forth [1,2]
The application of exogenous proline and L-cysteine could delay the increase of internal browning, so, the lowest level (19.03% and 22.43%) of browning index (BI) belonged to 15 mM proline and 0.4% L-cysteine respectively, after 28 days of storage (Figure 1a,b)
The mentioned treatments could prevent internal browning by controlling the activity of polyphenol oxidase (PPO) and preserved the texture and flavor of treated fruits
Summary
The flat peach (Prunus persica (L.) Batsch ‘Maleki’) as a mutation of the standard peach, has high economic value due to excellent texture and taste and being a unique source of phenolic compounds such as flavonoids, anthocyanin, and so forth [1,2]. The changes of texture occur as a result of pectin degradation enzymes such as polygalacturonase (PG) and pectin methylesterase. The oxidation of phenolic compounds mainly by polyphenol oxidase (PPO) leads to flesh and skin browning [3,4]. Storing the fruit in cold storage (close to 0 ◦ C) is suggested to alleviate undesirable changes and extend storage life. The high sensitivity of stone fruit to low temperatures and the appearance of some symptoms such as skin and flesh browning, declining flavor, mealy
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
