Biochemistry and Molecular Biology in Fruits during Cold Storage

Abstract

Cold storage of fruits is exploited to prolong postharvest life and marketing period by minimising their metabolic activity. However, exposure of fruits to nonfreezing low temperatures for prolonged periods of time may also lead to the development of cold‐inducible physiological disorders termed chilling injuries. Chilling injuries represent an economically relevant problem that may occur in an unpredictable way depending on the sensitivity of the fruits to low temperature. In this article, we consider the main aspects of cold stress signalling and responses taking place in fruits during storage and during the following period of warming at room temperature that often results in the further induction of chilling injury symptoms. A vast amount of research has contributed to the identification of several biochemical and molecular events underlying cold stress responses in fruits. Convincing evidence shows that ethylene plays a pivotal regulatory role, through a complex interplay with other hormones, but early inducing factors remain elusive. Recent studies based on system analyses of cold‐dependent trancriptomic and metabolomic changes have contributed to shed light on some early regulatory events which may contribute to determining the fruits' sensitivity to cold stress. A better understanding of these phenomena is essential to optimise cold storage conditions and for an efficient use of resources to deliver a more sustainable fruit supply chain.

Effects of Genotype, Storage Temperature and Time on Quality and Compositional Traits of Cherry Tomato

“…Fresh tomatoes commercialization is often characterized by significant temporal gaps among production and consumption. This implies the optimization of quality maintenance of the product along the distribution chain, in order to match the consumers' sensorial and nutritional demands [4]. Indeed, fresh vegetables are perishable commodities, whose postharvest decay represents a primary matter of social concern in terms of economic (loss of capital, fuel and manpower) and environmental costs (due to landfilling), associated to losses of valuable phytonutrients [5].…”

Transcriptomic Insights on the Preventive Action of Apple (cv Granny Smith) Skin Wounding on Superficial Scald Development

“…The early wounding signalling effect resulted to be based to a certain degree on the regulation of hormonal responses, an aspect that became evident by both GO analyses and by a gene-by-gene study approach. An early response to wounding in apple skins appeared to be the up-regulation of genes encoding the jasmonic acid (JA) biosynthetic enzyme allene oxide cyclase (AOC) and of genes involved in fatty acid desaturation (FAD) and in lipid metabolism (lipases), a typical adaption response to cold stress for increased membrane fluidity and reduction of cold inducible disorders [3,11,69,70]. Both these processes are known to be related to wounding and cold responses, respectively, and to be involved in priming of the tissues against abiotic stress.…”

“…One of the most important and most studied chilling injuries of apples is superficial scald due to its wide economic impacts in susceptible varieties (e.g., Granny Smith). Superficial scald is finally manifested with the necrosis within portions of the fruit epicarp and the first 5-6 hypodermal cell layers leading to the appearance of slightly sunken irregularly distributed brown skin patches on the surface of the fruits [2,3]. Superficial scald symptoms become manifest mainly during shelf life at room temperature (20 • C) following a period of cold exposure (−1 to 4 • C) of at least two-three months [2,4] and can be commercially controlled by different chemical treatments such as the application of antioxidants such as diphenylamine (DPA), 6-ethoxy-1,2-dihydro-2,2,4-trimethyl quinoline (Ethoxyquin), by treatment with the ethylene inhibitor 1-methylcyclopropene (1-MCP, 0.5 µL L −1 ) and/or by storage in low oxygen (LO 2 , <0.5%) atmosphere [5].…”

“…Chlorogenic acid can be further oxidised by polyphenol oxidase (MdPPO) which gene, according to several authors, is highly up-regulated during cold stress exposure and subsequent shelf life [2,9,10]. Recent studies have exploited omic approaches to uncover the overall molecular and metabolic changes that occur during both storage and shelf-life and are associated or not with scald development [3]. Most of these studies, aimed at the systematic identification of molecular and metabolic changes taking place during the triggering phase of scald induction and its subsequent phase of symptoms development, have relied on the use of DPA (or antioxidants) and 1-MCP (ethylene inhibition) as tools to create experimentally separate groups of apples characterised by a low potential for scald development as opposed to groups of apples with a high potential for scald development.…”

Performance Evaluation of Mobile Liquid Cooled Thermoelectric Refrigeration System for Storage-Cum-Transportation of Fruits and Vegetables

“…The refrigeration system provides a very effective and efficient cold chain infrastructure to the freshly harvested commodities for maintaining freshness with an extended shelf life. As a result, it extends the storage life of food up to several weeks or a month without deteriorating the quality of fresh produce until it reaches the end consumer [12]. By way of maintaining the physicochemical and nutritional quality of food for a longer period, the cold preservation technique not only reduces the food losses in physical form but also lessens the economic losses to the manufacturer, as well as avoids the foodborne illness instigated by the multiplication of bacteria and microorganisms [13,14].…”