Primary Metabolism in Fresh Fruits During Storage

Abstract

The extension of commercial life and the reduction of postharvest losses of perishable fruits is mainly based on storage at low temperatures alone or in combination with modified atmospheres (MAs) and controlled atmospheres (CAs), directed primarily at reducing their overall metabolism thus delaying ripening and senescence. Fruits react to postharvest conditions with desirable changes if appropriate protocols are applied, but otherwise can develop negative and unacceptable traits due to the onset of physiological disorders. Extended cold storage periods and/or inappropriate temperatures can result in development of chilling injuries (CIs). The etiology, incidence, and severity of such symptoms vary even within cultivars of the same species, indicating the genotype significance. Carbohydrates and amino acids have protective/regulating roles in CI development. MA/CA storage protocols involve storage under hypoxic conditions and high carbon dioxide concentrations that can maximize quality over extended storage periods but are also affected by the cultivar, exposure time, and storage temperatures. Pyruvate metabolism is highly reactive to changes in oxygen concentration and is greatly affected by the shift from aerobic to anaerobic metabolism. Ethylene-induced changes in fruits can also have deleterious effects under cold storage and MA/CA conditions, affecting susceptibility to chilling and carbon dioxide injuries. The availability of the inhibitor of ethylene perception 1-methylcyclopropene (1-MCP) has not only resulted in development of a new technology but has also been used to increase understanding of the role of ethylene in ripening of both non-climacteric and climacteric fruits. Temperature, MA/CA, and 1-MCP alter fruit physiology and biochemistry, resulting in compositional changes in carbon-and nitrogen-related metabolisms and compounds. Successful application of these storage technologies to fruits must consider their effects on the metabolism of carbohydrates, organic acids, amino acids and lipids.

Changes in Bioactive Compounds, Antioxidant Activity, and Nutritional Quality of Blood Orange Cultivars at Different Storage Temperatures

“…Citrus fruit taste depends on sugars and organic acids, which are reduced at higher rates compared with sugars and therefore, flavor changes after long-term storage [ 28 ]. In this study, cultivar and storage temperature affected the acceptability of blood oranges, and in many cases, subtropical crops, such as citrus fruit stored at lower than optimal temperatures, induce undesirable changes [ 36 ]. Overall, panelists gave the higher scores to “Sanguinello”, which could be attributed to a better balance between sugars and acids than the other cultivars, together with the enhancement of anthocyanins.…”

Fruit volatilome profiling through GC × GC-ToF-MS and gene expression analyses reveal differences amongst peach cultivars in their response to cold storage

“…This period can comprise 3–5 weeks including shipping, handling at production, and receipt 16 . Peach fruits are characterized by a rapid deterioration at room temperature 17 , 18 and therefore cold storage (0–1 °C) is commonly applied as the most suitable method for delaying ripening after harvest and extending fruit commercial life 19 , 20 . However, as in many fruit species, low temperature storage can lead to chilling injury (CI), a collective term for several visible physiological disorders that affect fruit quality 21 .…”

Changes in Bioactive Compounds, Antioxidant Activity and Nutritional Quality of Blood Orange Cultivars at Different Storage Temperatures

“…flavour changes after long-term storage [28]. In this study, cultivar and storage temperature affected the acceptability of blood oranges, and in many cases sub-tropical crops such as citrus fruit stored at lower than optimal temperatures induce undesirable changes [36]. Overall, panellists gave the higher scores to 'Sanguinello' which could be attributed to a better balance between sugars and acids than the other cultivars together with the enhancement of anthocyanins.…”