Fermentation adaptability of three probiotic Lactobacillus strains to oat, germinated oat and malted oat substrates

Abstract

Functional foods targeting the improvement of gastrointestinal health are widely recognized; of these, dairy-based probiotics are the most popular. Thus, the design of nondairy probiotics applying fruits, vegetables and cereals has raised great interest in the healthy food sector. The objective of this work was to assess the potential of germinated and malted oat substrates to support the growth of the probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus rhamnosus. Fermentations were carried out with distinctive oat substrates at inoculum levels of 3, 5 and 7% v/v, substrate concentrations of 3, 5 and 7% w/v and with sucrose addition 1·5% w/v. Lag phase profiles, maximum growth rates and maximal growths were evaluated; protein and sugar contents were also quantified. There was no significant effect (P > 0·05) of the inoculum size on the fermentation kinetics; however, oat media significantly affected the growth kinetics. In simple oat media, Lact. acidophilus exhibited biphasic growth patterns. Lactobacillus growth patterns were significantly affected (P < 0·05) by the supplementation with protein sources. The germination and malting processes significantly improved oats nutrient characteristics demonstrating to be adequate substrates for the fermentation with probiotic lactobacilli. Significance and impact of the study: In this work, the effect of oat media composition and fermentation conditions on the growth kinetics of three probiotic lactobacilli was determined. The variation in the inoculum levels did not have a significant effect on the probiotic cultures growth. Results revealed that protein supplemented simple, germinated and malted oat enhanced the cell viability of the probiotic lactobacilli; Lactobacillus casei exhibited better growth adaptability. The results also highlight that different weight in volume oat substrate concentrations has particular effects on Lact. casei growth kinetics. Our results contribute to a better understanding of oat-based media formulations as substrates for probiotic cultures.

Optimisation of fermentation conditions for probiotication of sorghum wort by Lactobacillus acidophilus LA5

“…This result was not in agreement with the study of Herrera‐Ponce et al . () which found that the inoculation dosage has no influence on the growth of the fermented oat‐based media. However, it has to be noted that the fermentation media was different from the medium used in our study, which could be the reason behind the disagreement.…”

Effect of potentially probiotic lactic acid bacteria on the physicochemical composition and acceptance of fermented cereal beverages

“…Furthermore, cereals are also potential viable substrates as they contain nutrients easily assimilated by probiotics (Martins et al, 2013). It has been demonstrated that oat, barley and malt substrates can improve lactobacilli tolerance to the harsh conditions of the gastrointestinal tract, and they can support the growth of single and mix-culture fermentations of probiotic microorganisms (Charalampopoulos & Pandiella, 2010;Charalampopoulos, Pandiella, & Webb, 2003;Herrera-Ponce, Nevárez-Morillón, Ortega-Rívas, Pérez-Vega, & Salmerón, 2014). Additionally, to the proven potential of cereal substrates to support the growth of probiotic microorganisms these have been associated with the risk reduction of chronic diseases such as obesity, cardiovascular disease, type 2 diabetes, and some cancers (Wang, He, & Chen, 2014).…”

Headspace gas chromatography (HS-GC) analysis of imperative flavor compounds in Lactobacilli-fermented barley and malt substrates

“…The five factors used in the experiment and their corresponding minimum and maximum levels are as follows: sampling temperature (50-90ºC); heating chamber agitation (300-700 rpm); volatiles extraction time (5-25 min); sample volume in glass vials (6-12 mL); sample pH (3)(4)(5)(6)(7)(8)(9)(10)(11). Therefore, the chosen experimental design comprised 2 5 =32 observations and three replicates were performed.…”

“…In this area of research, previous work have reported that beverages such as fruit and vegetable juices may be the next category of food matrices to serve as carriers of probiotic bacteria. Extending these ideas, we note that cereals are highly viable substrates as they contain nutrients easily assimilated by probiotics (4,5). Malt and barley extracts have exhibit their importance to improve lactobacilli tolerance to the harsh conditions of the gastrointestinal tract, and they can support the growth of single and mix-culture fermentations of probiotic microorganisms (6,7).…”