Effects of Lactobacillus acidophilus LA-3 on physicochemical and sensory parameters of açaí and mango based smoothies and its survival following simulated gastrointestinal conditions.

Abstract

The effects of the incorporation of Lactobacillus acidophilus LA3 (inoculated at 9 log CFU/mL) on physicochemical parameters, contents of sugars and organic acids, phenolic profile and sensory aspects of açaí (AS) and mango based smoothies (MS) during 28 days of refrigerate storage were assessed. The survival of L. acidophilus in AS and MS under simulated human gastrointestinal conditions during storage was also monitored. Counts of L. acidophilus LA-3 were approximately 8.5 log CFU/mL in AS and 7.5 log CFU/mL in MS after 1 day of storage and no changes (p ≥ 0.05) were observed in later evaluated storage time periods. Fruit smoothies (AS or MS) with L. acidophilus LA-3 presented lower (p < 0.05) contents of glucose, fructose and maltose and higher (p < 0.05) contents of lactic and succinic acids compared to those without L. acidophilus LA-3. Phenolic contents increased or decreased (p < 0.05) after 1 day of storage in AS and MS with L. acidophilus LA-3 and did not change (p ≥ 0.05) in AS or MS without L. acidophilus LA-3. The incorporation of L. acidophilus LA-3 increased the acidic flavor and fermented aroma in AS and MS. Viable counts of L. acidophilus LA-3 were approximately 7.5 and 8.5 log CFU/mL in AS and MS, respectively, at the end of in vitro digestion just after the incorporation, as well as on days 14 and 28 of storage. These results show the feasibility of incorporating L. acidophilus LA-3 into AS or MS and suggest these fruit smoothies as matrices for formulation of non-dairy beverages containing potentially probiotic lactobacilli.

Keywords: Fruit phenolics; Functional beverages; Lactobacilli; Probiotics.