Functional Exploitation of Carob, Oat Flour, and Whey Permeate as Substrates for a Novel Kefir-Like Fermented Beverage: An Optimized Formulation.

Sana M’Hir,Asma Mejri,Ali Zein Alabiden Tlais,Raffaella Di Cagno,Lamia Ayed,Pasquale Filannino

doi:10.3390/foods10020294

Abstract

This study investigated the fortification of a carob-based kefir-like beverage (KLB) with whey permeate (WP) and oat flour (OF). The response surface method was used to show the effect of WP and OF concentrations on lactic acid bacteria and yeast cell densities, pH, total titratable acidity (TTA), total phenolics content (TCP), DPPH radical scavenging activity, and overall acceptability (OA) in KLB. The statistical design provided thirteen formulations where OF concentration varied from 3% to 5% and WP from 10% to 15%. The enrichment of carob pods decoction with WP and OF had a positive effect on biomass production. Overall fermentation was shown to increase TPC of KLB. Furthermore, OF supplementation led to the higher levels of TPC and antiradical activity. WP negatively affected OA at linear and quadratic levels, whereas no effect of OF was observed at the linear level. The optimum point was found by using WP at 11.51% and OF at 4.77%. Optimized KLB resulted in an enrichment of bioavailable phenolics derivatives and highly digestible proteins.

Highlights

Functional beverages represent one of the fastest-growing segments in a novel food category and an attractive topic of study for researchers [1]
Kefir grains consist of a polysaccharide matrix, which vehicles a complex microbial consortium mainly composed of lactic acid bacteria in symbiotic association with yeasts and acetic acid bacteria [7]
Under the conditions of our study, we investigated the fortification of a carob-based kefir-like beverage (KLB) with

Summary

Introduction

Functional beverages represent one of the fastest-growing segments in a novel food category and an attractive topic of study for researchers [1]. Kefir grains consist of a polysaccharide matrix, which vehicles a complex microbial consortium mainly composed of lactic acid bacteria in symbiotic association with yeasts and acetic acid bacteria [7]. They ferment sugar substrates to produce organic acids, CO2 , ethanol, and multiple volatile flavor [8]. Kefir grains were used to ferment non-dairy substrates, such as tea and plant juices, to produce functional beverages enriched in bioactive compounds or able to vehicle potential health-promoting bacteria [9]. Under the conditions of our study, we investigated the fortification of a carob-based kefir-like beverage (KLB) with

Objectives

Methods

Results