Chemistry, Biochemistry, and Dietary Role of Potato Polyphenols. A Review

Abstract

Potatoes and other plant foods accumulate a variety of secondary metabolites, including phenolic compounds, phytoalexins, protease inhibitors, and glycoalkaloids, as a protection against adverse effects of mechanical bruising, light, and injury by predators including beetles, fungi, and insects. Since these phytochemicals are consumed by insects, animals, and humans as part of their normal diet, a need exists to develop a better understanding of the role of these compounds in both the plant and the diet. To contribute to this effort, this multidisciplinary overview describes analytical and compositional aspects of phenolic compounds in potatoes; their biosynthesis, molecular genetics, and role in host-plant resistance relationships; bruising-, ferrous ion-, and heat-induced discolorations such as after-cooking blackening and blackspot formation, which affect appearance and sensory properties of potatoes; polyphenol-oxidase-catalyzed enzymatic browning reactions and their prevention by chemical and plant molecular biology techniques; and effects of baking, cooking, microwaving, light, and γ-radiation on the stability of the major potato polyphenol, chlorogenic acid. Also covered are beneficial effects of phenolic compounds in the diet as antioxidants, antimutagens, anticarcinogens, antiglycemic, and hypocholesterolemic agents; adverse effects on protein nutritional quality; and recommendations for future research. Understanding the biochemical basis of stressinduced formation of polyphenols in plants, the chemistry of their transformations in the plant and in foods, and their functions in plant physiology, food science, nutrition, and health should stimulate interest in maximizing beneficial sensory, nutritional, and health effects of polyphenols in the diet. Such efforts should lead to better foods and improved human health.

Processamento mínimo de tubérculos de batata de baixo valor comercial

“…O pH dos tubérculos minimamente processados apresentou uma leve redução em função do armazenamento, cujas diferenças foram detectadas a partir dos 10 dias, porém manteve-se entre 5,0 e 7,0, conforme preconizados por Carvalho & Castro (2002). Os valores de acidez titulável foram menores nos tratamentos com o branqueamento (0,10 a 0,20), devido à utilização do ácido clorogênico na formação do complexo com o íon ferroso (Friedman, 1997). Os valores médios aumentaram durante o armazenamento (0,18 a 0,23), cujo aumento foi mais discreto nos tratamentos com o branqueamento.…”

“…A polpa crua de batata possui aproximadamente 17,4 mg 100 g -1 de vitamina C e, após o cozimento, esse valor é reduzido para 13,1 mg 100 g -1 (Chitarra & Chitarra, 2005 (Friedman, 1997). Portanto, a aplicação de branqueamento promove a formação de cor não característica de tubérculos recém descascados, o que poderia causar a rejeição da batata minimamente processada pelos consumidores.…”

Health benefits of finger millet (Eleusine coracana L.) polyphenols and dietary fiber: a review

“…Fortification of diets with food materials rich in phenolic acids was shown to impart antimutagenic, antiglycemic, and antioxidative properties, and this can be exploited in developing health foods (Friedman 1997). Utilization of Wholegrain cereals in food formulations is increasing worldwide, since they are rich sources of phytochemicals and dietary fiber which offer several health benefits (Jones and Engleson 2010).…”

Antocianinas, ácido ascórbico, polifenoles totales y actividad antioxidante, en la cáscara de camu-camu (Myrciaria dubia (H.B.K) McVaugh)

“…La importancia de los antioxidantes es crucial para la salud, debido a su capacidad de neutralizar radicales libres, que contienen uno o más electrones desapareados (THOMAS, 2000), siendo responsables de muchas enfermedades degenerativas, cataratas, artereoesclerosis, muerte celular y cáncer, asimismo por su capacidad de eliminar y atrapar potencialmente a los electrófilos dañadores del ADN, metales tóxicos, hasta la inhibición de enzimas activadoras de precarcinógenos, hasta carcinógenos (FRIEDMAN, 1997). El antioxidante al colisionar con el Radical Libre (RL) le cede un electrón, oxidándose a su vez y transformándose en un RL débil no tóxico (PERÓN; LÓPEZ; J. R. M.; LÓPEZ, Y. T, 2001;ZHENG;WANG, 2001).…”