Métodos tradicionais e emergentes para evitar o escurecimento enzimático de vegetais

Abstract

Enzymatic browning is a common problem, especially in fruits and vegetables when they suffer mechanical damage, such as a cut, exposing their tissue to oxygen and the action of some enzymes, such as polyphenoloxidase and peroxidase. This exposure leads to darkening of tissues and consequently loss of quality. In some cases, enzymatic browning may begin with intact plant tissue. Because it is a problem that directly affects the quality and consequently the acceptance of the product by the consumers, it is necessary to search for processes that can avoid or delay the effects of the enzymatic dimming. Therefore, this work aims to review the main methods used to avoid the enzymatic browning of vegetables. One of the most obvious and most used methods to prevent such a reaction from occurring is by bleaching with hot water or using steam. However, these methods can lead to some nutrient losses. Therefore, many other processes have been developed and improved such as microwave bleaching, high temperature and hot air impact bleaching, ohmic heating, irradiation, edible films, genetic modification and the use of chemical agents, methods that will be addressed in this job. The enzymatic darkening reaction in fruits, vegetables and their derivatives are one of the main problems in the food industry, so technological advances in the conservation of these products stimulate research to control this darkening, consequently improving the quality and conservation of these foods.