Development of probiotic yogurt from almond and cow’s milk using Lacticaseibacillus rhamnosus GR-1

Abstract

Purpose

The purpose of this study is to evaluate the effect of almond milk supplementation on the growth and viability of Lacticaseibacillus rhamnosus GR-1 (LGR-1) in yogurt samples over 6 h of fermentation and 30 days of refrigerated storage.

Design/methodology/approach

Four yogurt treatments (T1–T4) were inoculated with the probiotic strain L. rhamnosus GR-1 and fermented for 6 h at 37°C and then placed in refrigerated storage at 4°C for 30 days. Microbial and pH analysis of each sample was conducted every 2  h throughout the fermentation period and on Days 1, 15 and 30 of cold storage to determine the viability of L. rhamnosus GR-1.

Findings

All samples achieved mean microbial counts of at least 108 CFU/mL during fermentation and storage. During fermentation, mean microbial counts increased for all treatments; however, differences in mean microbial counts between treatments were not significant. During storage, the mean microbial count for T4 at 15 and 30  days was significantly higher (p = 0.031) than microbial counts on Day 1. However, mean microbial counts did not differ significantly across all storage time points for treatments 1, 2 and 3 (p > 0.05). These results suggest that the addition of almond milk, in combination with cow’s milk, is suitable for propagating and preserving the viability of L. rhamnosus GR-1 in yogurt.

Originality/value

There is a consumer shift towards plant-based products due to health, environmental and ethical reasons. Almond milk is a popular nondairy alternative that provides enhanced nutritional value to traditionally dairy-based probiotic yogurts. L. rhamnosus GR-1 is an especially beneficial probiotic for women as it colonizes the gut and vaginal epithelium, promoting urogenital health, including preventing the recurrence of urinary tract infections and bacterial vaginosis.

Citation

Burrowes, R. and Hekmat, S. (2023), "Development of probiotic yogurt from almond and cow’s milk using Lacticaseibacillus rhamnosus GR-1", Nutrition & Food Science, Vol. 53 No. 6, pp. 995-1004. https://doi.org/10.1108/NFS-06-2022-0194