Avaliação de parâmetros físico-químicos, microbiológicos e nutricionais de folhas de couve tratadas com luz ultravioleta em função do tempo de armazenamento

Abstract

The consumption of fresh and nutritious food has become a common practice in people's lives, especially with the overall growth of the healthy lifestyle tendency. In this field, leafy vegetables stand out due to their many nutritious properties. As a food that does not undergo heavy processing and is many times consumed raw, microbiological quality of kale leaves is extremely important and can be related to the product's safety and also its shelf life. Ultraviolet irradiation, known for its DNA-damaging potential, is one of the many alternatives that aim to reduce microbial load while maintaining food safety. It can be seen as an alternative to commonly-used technologies that rely on chemical agents to sanitize vegetables in general. The present study compared the effect of UVC LED treatment and a conventional sanitizing method (soaking vegetables in sodium hypochlorite solution) applied to kale leaves (Brassica oleracea L. var. acephala). Mesophile and psychrotrophs counts, as well as total phenolic, clorophylls and mineral (iron, potassium and calcium) content were evaluated using Tukey's test to a 5% significance level. The microbiological results were positive, with LED UV-C treatment being effective in reducing microbiological counts of quality indicators. The physical chemical and mineral results are in accordance with the results observed in studies that seek to make the technology viable, even though many other evaluations (including tests with specific microorganisms) must be conducted to solidify the usage of UV-C technology.