Desenvolvimento e avaliação de revestimento comestível com adição de antifúngicos naturais para a proteção de morangos

Abstract

The strawberry is a highly perishable fruit for possessing high respiratory rate, great sensitivity to climate and mechanical damage. These factors are associated with a high susceptibility to attack from pathogens, especially fungi, during cultivation and after harvest, leading to economic losses and final product quality. Hoping to solve these problems have been adopted the practice of indiscriminate use of antifungal chemicals, which can lead to residual contamination of fruit and consequently, harm who consumes. In this context stands out the importance of the development of techniques to replace the use of fungicides chemicals which, in your most, are harmful to one's health. The aim with this test, apply and evaluate edible coatings added to crude extract hydro-alcoholic of Aloe (Aloe vera), Lemongrass (Cymbopogon citratus) and Ginger (Zingiber officinalle) in strawberries, to control fungal development and increase the shelf-life after harvest. The coatings to be applied on Strawberry were developed from four filmogenics agents: manioc starch, xanthan gum, corn starch and pregelatinized starch. The water solubility test in coatings produced from the casting technique, being the manioc starch, by offering lower solubility, selected for the continuity of the study. For the test for the application of coatings were used organic strawberries camarosa varieties, randomly divided into homogeneous groups. The strawberries were added separately in filmogenics solutions containing plant extracts only manioc starch and a group remained untreated for the control. The strawberries were sanitized and, except do control, immersed in the filmogenic solution and drained on screens. After that, were placed in an oven temperature controlled the BOD 25 °C for a period of seven days, during which took place as periodic physical-chemical analyses of CR, loss of mass, soluble solids, acidity and pH. The results obtained on the physico-chemical analyses and the visible effects of fungal infestation and appearance, revealed that manioc starch film proved more effective than the control group, however the groups treated with the film added with no extracts were more effective than the control, with the exception of some samples treated with ginger. It is assumed that the low interaction of extracts with manioc starch led to formation of cracks in the film after application in the fruit which could leave the surface of the fruit is susceptible to fungal attack. This work’s results that might be useful in further studies aimed at optimizing the use of cassava starch in plant extracts in the production of edible films for protection. However will require new tests in order to better evaluate the in situ antifungal action of these plant extracts.