This review examines the parameters of enzymatic browning in apple and apple products that is, phenolic compounds, polyphenoloxidases, and other factors (ascorbic acid and peroxidases), both qualitatively and quantitatively. Then the relationships between intensity of browning and the browning parameters are discussed, including a paragraph on the methods used for browning evaluation. Finally, the different methods for the control of browning are presented.

Enzymatic browning reactions in apple and apple products

Anthocyanins are a group of natural occurring pigments responsible for the red-blue colour of many fruits and vegetables. Anthocyanins are of interest for two reasons because they cannot only be used in the technological field as natural colorants but also have important implications in the field of human health. Numerous studies indicate the potential effect that this family of flavonoids may have in reducing the incidence of cardiovascular disease, cancer, hyperlipidemias and other chronic diseases through the intake of anthocyanin-rich foods. This review examines existing literature in this area: from plant content and distribution to health implications, including the effect of agronomic and genetic modifications on the anthocyanin content of plants as well as other biotechnological factors and food processing. The bioavailability, metabolism, bioactivity, and epidemiology of anthocyanins will also be reviewed.

Anthocyanins: from plant to health

External control of anthocyanin formation in apple

This paper proposes a concept based on applying postharvest abiotic stresses to enhance the neutraceutical content of fresh fruits and vegetables.We hypothesize that selected abiotic stress treatments, such as wounding, phytohormones, temperature, ultraviolent light, altered gas composition, heat shock, and water stress, among others,will effect the secondary metabolism of fresh produce and increases the synthesis of phytochemicals with neutraceutical activity or reduce the synthesis of undesirabe compounds.Controlled stresses may be used as tools by the fresh produce industry to enhance the health benefit properties of fresh-cut or whole fresh produce and by the food processing and dietary suppliment. Industries to obtain healthier processed products or enhance extractable nutraceuutical yields.

The Use of Controlled Postharvest Abiotic Stresses as a Tool for Enhancing the Nutraceutical Content and Adding-Value of Fresh Fruits and Vegetables

The literature of the regulation of color in apple skin is reviewed and compared with current knowledge of the regulation of flower color. Color in apple skin is a blend of various amounts of chlorophyll, carotenoids, and anthocyanins/flavonols. A variety of red colors are produced by cyanidin glycosides copigmented with flavonols and other compounds. The concentration and identification of flavonols, proanthocyanidins, and cyanidin glycosides in apple skin are tabulated. From a knowledge of the pigments present in apples, and the biosynthetic pathway present in flowers, a possible biosynthetic pathway to cyanidin glycosides, proanthocyanidins (e.g., catechin), and flavonols (e.g., quercetin glycoside) can be derived. Anthocyanin biosynthesis is developmentally regulated; flavonols and proanthocyanidins are high in juvenile fruit, decrease in concentration during fruit growth, and then increase during fruit ripening. In some cultivars, anthocyanins also increase during ripening. Light is a key re...

J.D. Faragher

Papers

Anthocyanin accumulation in apple skin during ripening: Regulation by ethylene and phenylalanine ammonia-lyase