Impact ofSaccharomyces Cerevisiaeon Viability of ProbioticLactobacillus Rhamnosusin Fermented Milk under Ambient Conditions

Abstract

The viability of probiotic Lactobacillus rhamnosus HN001 was examined in fermented milk with and without Saccharomyces cerevisiae var. bayanus EC‐1118. The yeast enhanced the viability of L. rhamnosus at 30C but not at 12C. High temperature (40C) was detrimental to yeast vitality and diminished its viability‐enhancing effect. The yeast inoculated at 103 cfu/g multiplied to 106 cfu/g and enhanced the viability of L. rhamnosus. Viable yeast exerted maximum beneficial effects, although the cell‐free yeast supernatant also enhanced the survival of L. rhamnosus. The addition of yeast after fermentation decreased its viability‐enhancing effect. Removal of oxygen achieved the viability of L. rhamnosus that was comparable with that achieved in the presence of viable yeast. The results suggest that the improved viability of L. rhamnosus might involve yeast viability, oxygen removal and yeast metabolite(s). The findings would help develop novel microbial starter technology for ambient‐stable fermented milks with live probiotics. Practical Applications Maintaining cell viability of probiotics is a scientific challenge, especially under ambient conditions. The findings of this study would lay the foundation for developing novel microbial starter technology for ambient‐stable fermented foods with high cell counts of live probiotics, which entails stringent process and engineering control to ensure hygienic conditions and product safety. Benefits of such products would include: reducing distribution and storage costs by saving capital cost involved in chilled‐chain distribution, storage and retailing; market penetration and growth where it was not possible due to a lack of or poor refrigeration; extending shelf life and increasing consumer convenience.

Antioxidant activities of kombucha prepared from three different substrates and changes in content of probiotics during storage

“…The low pH value (3.15) of LGTK may be due to the rapid decrease of LAB in kombucha. In addition, it has been reported that the yeast enhanced the viability of L. rhamnosus at 30 o C but not at 12 °C (Suharja et al, 2012). The low temperature (4 °C) used in the present study may have reduced the viabilityenhancing effect of the yeast against LAB.…”

Probiotic Potential of Yeasts Isolated From Traditional Indian Fermented Foods

“…Saccharomyces cerevisiae is the only clinically proven yeast being used as a human probiotic and has shown to positively influence host's health by antimicrobial effect, nutritional effect, inactivation of bacterial toxins, quorum sensing, trophic effects, immunomodulatory effects, anti-inflammatory effects, cell restitution and maintenance of epithelial barrier integrity [83,84]. Candida tropicalis is a well-known yeast species found all over the world, and not only colonizes animal's gut has been known to exert nutritional and other nutritional probiotic effects in the host, such as production of phytase [85].…”

Saccharomyces cerevisiae EC-1118 enhances the survivability of probiotic Lactobacillus rhamnosus HN001 in an acidic environment

“…Recently, the use of yeasts as a novel means to enhance the survivability of probiotics in foods has also been explored (Liu and Tsao 2010;Suharja et al 2014). Liu and Tsao (2009) demonstrated the potential of co-culturing different combinations of yeasts and probiotic bacteria to enhance the survival of the probiotics in fermented milk stored at 30°C.…”