Smith, June; Mishra, Niharika (Weber State University)
Faculty Advisor: Oberg, Craig (Weber State University, Microbiology); Culumber, Michele (Weber State University, Microbiology)
Non-dairy food options have become a growing cultural necessity, however, providing fermented or probiotic supplemented non-dairy alternatives is difficult. Little is known about the activity and survival of probiotic cultures in dairy alternatives. We evaluated the activities of several probiotics at various concentrations and in different combinations in oat, almond, and coconut beverages. Probiotic culture strains of Streptococcus thermophilus (YFLO1), Lactobacillus rhamnose (LGG), L. casei (Casei 431), and Bifidobacterium animalis subsp. lactis (BB12), and commercial probiotic mixtures, YFLO2, and Fresh Q, were inoculated in MRS broth, transferred to MRS agar plates, and incubated anaerobically for 24 hours at 37_. BB12 was grown anaerobically in MRS + cystine broth and agar. Isolated colonies were assayed on API 50 CH panels, and a carbohydrate use panel was developed for each organism. Oat, almond, and coconut beverages were inoculated in duplicate with the isolated strains and incubated in a water bath at 40_. The pH was recorded at regular intervals for up to 41 hours. The oat beverage had the most rapid and significant pH change, when incubated with either YFLO1, casei431, and LGG, dropping between 1.5 to 3 pH units over 3 hours depending on the culture. The almond and coconut beverages did not show rapid pH change with the organisms tested. Due to the quick decrease in pH change, further tests on the oat beverage. It was inoculated with Lactobacillus casei 431, LGG, and YFLO1. Organisms were tested at 0.5%, 1.0%, and 2.0% concentrations in oat beverage in triplicate. These inoculations were again incubated at 40°C and pH monitored after 5 hours, then plated on MRS agar plates after 24 hours. Final ranged between 1.0 x 109 - 1.8 x 109 for the 1% inoculum. It appears that these organisms survive, and may even grow in the oat beverage. This research demonstrates that probiotic cultures can grow in non-dairy beverages and can ferment the available carbohydrates and decrease pH. These results provide insights that can be used for beverages, yogurt, ice cream, and other fermented food production.