Effects of calcium chloride treatment on softening in red raspberry fruit during low‐temperature storage

Abstract

Fruit softening is an inevitable event during ripening of red raspberry fruit even when stored at low temperature. In this research, the effects of CaCl 2 treatment on softening of red raspberry during storage at 4°C were studied. The results indicated that CaCl 2 treatment effectively delayed the decrease of firmness and reduced the respiration rate of red raspberry fruit during storage. The CaCl 2-treated fruit maintained higher protopectin content and lower soluble pectin content compared with controls. The cellulose and starch contents in the fruit treated with CaCl 2 kept higher than in the control during storage. Moreover, CaCl 2 treatment decreased activities of polygalacturonase (PG), pectin methylesterase (PME), and cellulase (Cx) mainly at the early stage of softening. Application of CaCl 2 lead to the decreased activities of amylase (AM) and β-galactosidase (β-gal) compared with controls during the entire storage periods. These results indicated that CaCl 2 treatment might delay postharvest softening of red raspberry fruit stored at low-temperature by retarding cell wall degradation and starch hydrolysis. Practical applications Red raspberry fruit is very popular with consumers because of its high-nutritional value and anticancer effects. However, it has a very short postharvest life and softens easily even when stored at low temperature, which limits its distribution to distant market. Our data indicated that CaCl 2 treatment delayed postharvest softening of red raspberry fruit stored at low temperature. The results could provide preliminary yet essential information to research community to further study the molecular mechanisms of softening in red raspberry fruit, and also provide reference data for maintaining quality of postharvest red raspberry fruit.

Effect of calcium chloride and 1-methylcyclopropene combined treatment on pectin degradation and textural changes of Eureka lemon during postharvest storage

“…Previous studies showed a strong relationship between pectin degradation and decline in DE of citrus fruits during postharvest storage ( Frempong et al, 2022 ). Contrary to reports on the effect of the postharvest application of 1-MCP or CaCl₂ on PME and other cell wall enzymes activities, fruits such as Mandarin, two varieties of Ber fruit, and red raspberry showed a reduction in PME activities during storage after treatment ( Jain et al, 2019 ; Baswal et al, 2020 ; Lv et al, 2020 ). This could support the reason why the rate of decline in the intensity of red color to the somewhat orange color for the control fruits was higher than that of the treated fruits.…”

Inhibitory Effects of CaCl2 and Pectin Methylesterase on Fruit Softening of Raspberry during Cold Storage

“…Firmness reduction of fruit during ripening is attributed to cell wall degradation and the loss of cell structure [16]. Application of calcium could effectively maintain the structural integrity of the cell wall and thereby maintain or even improve the texture and quality of fruit during storage [10].…”

“…Fruit firmness was determined using TA.XT. Plus texture analyzer (Stable Micro Systems Ltd., Godalming, Surrey, UK) equipped with a 50 mm probe according to the method described previously [16]. Fruit samples were compressed to a degree of 30%.…”

“…At present, calcium treatment alone or combined with other reagents have been widely applied in improving texture and maintaining the quality of papaya [12], persimmon [13], cherry tomato [14], and sweet cherry [15] during storage. Recently, Lv et al (2020) mentioned that CaCl 2 treatment delayed the fruit softening of raspberry as indicated by the reduction of activities of PG, pectin methylesterase (PME), and cellulase (Cx), as well as the maintenance of protopectin content [16].…”

Cell Wall Calcium and Hemicellulose Have a Role in the Fruit Firmness during Storage of Blueberry (Vaccinium spp.)

“…The role of calcium in fruit ripening processes, its interaction with the cell membrane and the cell wall, and development of physiological disorders has been studied for a long time [ 23 , 24 , 25 , 26 , 27 ]. There are varied publications describing the effect of calcium on the fruit quality of different species such as apple [ 28 ], pear [ 29 ], cherry [ 30 ], grape [ 31 , 32 ], peach [ 33 ], and berries [ 34 , 35 ], among others. In blueberry, the use of different compounds containing calcium has been studied in soil applications, foliar and solution dips [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ].…”