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Abstract
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Background: The ‘functional foods” are considered enriched or fortified foods that provide health benefits besides providing essential nutrients (like minerals and vitamins) when consumed at efficacious amounts as part of a regular diet. Among the different types of functional foods, maximum attention has been paid to probiotic foods both as therapeutic supplements and health-promoting foods. Probiotic microorganisms ferment sugars and produce lactic and other organic acids. Tarhana, a traditional fermented cereal-based food of Iran, is prepared with a mixture of cereal flours, vegetables, herbs, spices, and yogurt. The objective of this study was to improve the survival of lactic acid bacteria (LAB) in Tarhana soup as a non-dairy matrix. Methods Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophiles were encapsulated in electrospun nanofiber mats fabricated from corn starch (CS) and sodium alginate (SA) and the protective effect of the nanofibers on the cells during the preparation of Tarhana and in the gastrointestinal tract were investigated. Results: The moisture contents of the control and nanofiber-loaded dried Tarhana samples were 8.75 and 8.71%, respectively; therefore, using nanofiber mats in the formulation had no significant effect on the moisture content of the samples. A negative zeta potential value of -15.1mV was found for LAB-loaded nanofibers. The nanofibers mats prepared from SA and CS mix showed a bead-free and clean structure with uniformity in size. The diameter size of most of the fibers was ranged from 175-338 with an average of 265 nm (Fig. 1a). Loading nanofiber mats with L. delbrueckii subsp. bulgaricus and S. thermophilus cells led to a uniform distributed beaded structure as seen in Fig. 1b and the average diameter enhanced to approximately 763 nmThe viability of L. delbrueckii and S. thermophilus at the end of the electrospinning were 92.82% and 95.83% indicating a slight loss in their population. Survival of nanoenca
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