Biological membrane deterioration and associated quality losses in food tissues

Abstract

Biological membranes are rarely considered by food scientists when the deteriorative reactions that take place during the processing or storage of food tissues are studied. Yet, membranes and their deterioration play a major but underestimated role in food losses, and recent biochemical information indicates that at least some of these reactions can be controlled by procedures suited to food materials. Much of the present information available on membrane degradation in food systems is incomplete and speculative. It is known, however, that in order to accomplish their many indispensable functions in cells, membranes are constituted mainly of phospholipids, protein, and some carbohydrates arranged in thin, bimolecular sheet-like structures that serve to compartmentalize cells and their organelles. Membranes have embedded in their asymmetric surfaces complements of catalytic and cytoskeletal proteins that serve permeability and structural functions. Membrane surfaces exhibit fluidity, due partially to the continuous lateral diffusion of lipids and some proteins. Two important consequences of fluidity are the ability of membrane phospholipids to exist in different interconvertible conformational phase structures and the formation of heterogenous lipid domains on the membrane surface. Cellular death leads unavoidably to the initiation of membrane deterioration. While the time course of this series of reactions differs in animal and plant tissue, they are damaged by generally similar mechanisms. These include an initial peroxidative attack on polyunsaturated fatty acids, with the concomitant production of free radicals. Many biological agents can act as accelerating agents in these reactions, including transition metal ions, heme compounds, radiation, illuminated chlorophyll, calcium, and ethylene. Once formed, free radicals catalyze further reactions that can affect all aspects of membrane function and cellular metabolism, and lead ultimately to significant losses in food quality through defects such as chilling injury and cold shortening. These are aggravated by many food-processing steps, especially those that involve tissue disruption. Control of membrane breakdown by exogenous chemical intervention has been practiced, but, at best, this only slows the rate of these reactions. Newer approaches to this problem include dietary treatment of meat animals, modified storage and packaging conditions, and genetic interventions. This review advances the proposition that membrane deterioration can be considered a "universal mechanism" that leads to significant quality losses in food. Perhaps because the study of biological membranes and the biochemical and physiological properties has only begun recently, not much progress has been made in finding practical control mechanisms for these reactions in food systems.(ABSTRACT TRUNCATED AT 400 WORDS)

Role of internal atmosphere on fruit ripening and storability—a review

“…Combined treatment also increased total volatile compounds during storage (although there were quantitative and qualitative changes depending upon the individual volatile compound) (Ayala-Zavala et al 2005). In view of the above reports, plant volatiles are important because fruits are reported to be accompanied by increase in the levels of reactive oxygen species during their maturation and ripening and this situation represents an oxidative stress like condition for fruits (Stanley 1991;Ferrie et al 1994;Palma et al 1995;Rogiers et al 1998). These examples show that at least some of the volatiles in the internal atmosphere of fruit can provide protection against biotic and abiotic stresses during ripening and storage and reflect the potential practical applications of these volatiles in overall postharvest management of fruits.…”

Feeding wet distillers grains plus solubles contributes to sarcoplasmic reticulum membrane instability

“…It is likely there were still plenty of antioxidants available to prevent membrane lipid oxidation early post-mortem, so the pre-rigor time course of calcium release was not be affected by the greater PUFA content in the SR membrane. In fact, Stanley (1991) hydrocarbon chain packing, thereby better preserve membrane integrity at lower temperature. An example of a western blot used to quantify TNT degradation is presented in Fig.…”

Salicylic acid treatment saves quality and enhances antioxidant properties of apricot fruit

“…Apricot fruits during cold storage were reported to show chilling injury symptoms and a high percentage of fruit decay (Stanley 1991). It is well known that apricot fruit starts to lose its physical and chemical quality (e.g.…”

“…It is well known that apricot fruit starts to lose its physical and chemical quality (e.g. fruit firmness, increased fruit acidity and reduction in soluble solid content) directly after harvest and through the storage period (Stanley 1991;Ezzat et al 2012).…”

“…Apricots as climacteric stone fruits have a limited post-harvest life and they remain fresh only for 2-4 weeks stored at 0°C depending on cultivar (Stanley 1991;Crisosto et al 1995). Apricot fruits during cold storage were reported to show chilling injury symptoms and a high percentage of fruit decay (Stanley 1991).…”