Development and evaluation of fermented milk with Lactobacillus acidophilus added to concentrated cranberry (Vaccinium macrocarpon) juice with the potential to minimize the recurrence of urinary tract infections

Abstract

Repeated urinary tract infections affect many people worldwide. A potential strategy to reduce the incidence of these infections is to consume probiotics and cranberry fruit regularly. In this context, this study aims to prepare fermented milk with Lactobacillus acidophilus La-5 added with concentrated cranberry juice in two concentrations (5 and 10 %, corresponding to C1 and C2 samples, respectively) and evaluate different technological aspects of the samples after production and during storage, and comparing with the control sample (C). The juice had pH 1.91, 70.09 % of solids, and total proanthocyanidins and A-type proanthocyanidins (PACs) values of 117.03 mg/100 g and 16.38 mg/100 g, respectively. The higher the juice content added to the product, the higher the acidity (1.4 and 2.6 g of lactic acid in 100 g, corresponding to C1 and C2 on day 1 (D1), respectively), the total proanthocyanidin content (1.96 and 4.01 mg/100 g on D1; and 1.31 and 3.05 mg/100 g on day 28 of storage (D28), corresponding to C1 and C2, respectively) and A-type proanthocyanidin (0.56 and 1.26 mg/100 g in Day 1; and 0.54 and 1.19 mg/100 g in D28, corresponding to C1 and C2, respectively), higher the values of the color parameters (L*a* and C*), and lower pH value, probiotic viability, and sensory acceptance. Furthermore, the rheological parameters demonstrated a stronger protein network due to the addition of cranberry. The new formulations, including samples C1 and C2, are alternatives as functional products, which regular consumption probably has the potential to minimize the recurrence of urinary tract infections.