Microbial and Physical Properties of Probiotic Fermented Milk Supplemented with Lentil Flour

Fatemeh Zare,Benjamin K Simpson,Claude Champagne,Joyce I Boye,Valerie Orsat

doi:10.5539/jfr.v1n1p94

Abstract

Skim milk (9.5 % w/v solid content) was supplemented with 1-3% (w/v) lentil flour or skim milk powder, inoculated with Lactobacillus rhamnosus AD 200 at 37 ?C and stored at 4 ?C. Acid production during the fermentation, microbial growth, physical (pH, syneresis, and color) and rheological (dynamic oscillation temperature sweep test at 4-50 ?C) properties, were studied after production and during 28 days. Milk supplementation with 1-3% lentil flour enhanced acid production, and the microbial population (CFU) of L. rhamnosus was comparable with that of the non-supplemented control after production. After 28 days, the CFU of 2% and 3% lentil-supplemented probiotic were as high as 1% skim milk supplemented sample. All lentil flour-supplemented samples had significantly lower “L” values and higher “b” and “a” values. Probiotic products with 1-3% lentil flour showed higher storage (G?) and loss (G?) moduli compared with 1-3% skim milk supplemented samples and the non-supplemented control.

Highlights

Probiotics are “live microorganisms which when administered in adequate amounts confer health benefits to the host” (Araya et al, 2002)
As milk has greater buffering capacity in comparison with lentil flour (Table 1), the greater acidification rates in products supplemented with lentil flour could have been partially due to their lower buffering capacity when compared to the corresponding skim milk-supplemented probiotic products
This study showed that supplementation of probiotic beverages with 1-3% lentil flour results in a significantly faster lowering of the pH than 1-3% skim milk powder, suggesting that the fermentation process was significantly faster in 1-3% lentil-supplemented probiotic samples

Summary

Introduction

Probiotics are “live microorganisms which when administered in adequate amounts confer health benefits to the host” (Araya et al, 2002). The health benefits of probiotics have been known for a long time, dating from the very early ages when Hippocrates and other scientists reported that fermented milk could heal certain digestive disorders (Ranadheera et al, 2010). Élie Metchnikoff is, considered in recent history to have discovered probiotics (Heller, 2001). He noticed with greater longevity in Caucasian populations who frequently consumed fermented milks and proposed that the acid-producing organisms in fermented dairy products stopped “fouling” in the large intestine, leading to prolongation of a healthy life (Heller, 2001). Recent studies have indicated that probiotic bacteria can provide several therapeutic advantages, such as modification of the immune system, blood cholesterol reduction, lessening of lactose intolerance, maintained remission of Crohn's disease, healing of diarrhea, and prevention of infections of uro-genital organs (Hekmat, Soltani, & Reid, 2009)

Methods

Results

Conclusion