Optimization of the growth ofLactobacillus in skim milk added with green banana flour and determination functional properties

摘要

Purpose - This paper aims to study the effect of addition of green banana flour (GBF) in skim milk, provides a nutritional and functional contribution to this matrix when added. They have biological compounds like resistant starch, phenolic compounds,antioxidant compounds and others. The skim milk containing 1.08 per cent of GBF was chosen after a central composite rotational design and response surface methodology. The response variable was the growth of Lactobacillus plantarum (LP) and Lactobacillus helveticus (LH). Design/methodology/approach - During the fermentation process, the antioxidant activity, plasmid DNA protection capacity, proteolytic activity and inhibitory activity of angiotensin-converting enzyme (ACE) of the fermented milk was determined.Findings - All variables were influenced by the fermentation time. The antioxidant activity evaluated by the ABTS radical presented values of 0.83 ± 0.04 fiM Trolox.mL-1 and 0.79 ± 0.02 Trolox.mL-1, respectively, for the fermented LP and LH The extracts fermented by L. plantarum and L helveticus were able to inhibit the oxidation of plasmidial DNA. The proteolytic activity was higher in the fermented with LH (1.16 ± 0.03) than in the fermented with LP (0.71 ± 0.02). The ACE inhibitory activity was higher in the fermented LH (59.01 per cent) than in the fermented LP (54.45 per cent).Originality/value - Fermented milk with 1.08 per cent GBF presented positive results in the analyzed variables and could be studied commercially as a functional food alternative.