Evaluation of the effect of supplementing fermented milk with quinoa flour on probiotic activity

• Grant number: 14/14834-3
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: August 01, 2014
• End date: January 31, 2015
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Science
• Principal Investigator: Ana Lúcia Barretto Penna
• Grantee: Ana Lúcia Barretto Penna
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

In this work we investigated the effect of supplementing fermented milk with quinoa flour as an option to increase probiotic activity during fermented milk production and storage. Fermented milk products were produced with increased concentrations of quinoa flour (0, 1, 2 or 3 g/100 g) and submitted the following analysis at 1, 14, and 28 days of refrigerated storage: post acidification, bacterial viability, resistance of probiotics to simulated gastrointestinal (GI) conditions and the adhesion of probiotics to Caco-2 cells in vitro. The kinetics of acidification were measured during the fermentation process. The results for tVmax, tpH5.0 and tpH4.6 were similar for all treatments. Therefore, adding quinoa flour had no effect on the fermentation time; however, it contributed to post-acidification of the fermented milk during storage. Quinoa flour did not affected the counts of B. animalis subsp. lactis BB-12 and L. acidophilus La-5 during the storage, it did not protected the probiotic strains during simulated GI transit and did not have a positive effect on the adhesion of probiotic bacteria to Caco-2 cells in vitro. Additionally, the adhesion of strains to Caco-2 cells reduced during the refrigerated storage of fermented milk. Although the addition of at least 3% quinoa flour had a neutral effect on probiotic activity, its incorporation to fermented milk can be recommended because it is an ingredient with high nutritive value which may increase the appeal of the product to consumers. (AU)