Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt

Abstract

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate (SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5* plant extract, 0.25* SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis,Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage.

Investigating the effect of aqueous extracts of basil and savory on antioxidant activity, microbial and sensory properties of probiotic yogurt

“…Increases in E h and the hydrogen peroxide concentration coming from the metabolic activity of bacteria can lead to a reduction in bacterial counts during storage (Dave and Shah, 1997). Michael et al (2015) reported similar results when investigating the effect of adding herbal extract on the viability of Lactobacillus delbrueckii ssp. bulgaricus and Lactobacillus acidophilus in probiotic non-fat yogurt.…”

“…The reason for this is the fact that milk fermentation with the herbal extracts increased the metabolic activity of the yoghurt bacteria, thus elevating the yoghurt acidity due to the production of organic acids by lactic acid bacteria (Amirdivani and Baba, 2011). Furthermore, the acidity of all samples increased significantly during storage (p < 0.05), because as the storage time increased, the lactose fermentation by the starter and probiotic bacteria proceeded, and acidity increased due to the accumulation of organic acids such as lactic acid and formic acid (Michael et al, 2015). Joung et al (2016) obtained similar results.…”

Means to Facilitate the Overcoming of Gastric Juice Barrier by a Therapeutic Staphylococcal Bacteriophage A5/80

“…To our surprise, yogurt turned out to be relatively efficient in protecting phage from stomach juice, despite that in the case of milk no clear effect was observed. This may be associated with mildly acidic pH of Danone natural yogurt (5.29 according to Çaglar et al, 2011) and with the yogurt buffering activity (Kargul et al, 2007). In in vivo studies, the ingestion of yogurt was shown to stabilize the gastric pH for 1 h at the level exceeding 3.5 (Martini et al, 1987).…”

Some current applications, limitations and future perspectives of lactic acid bacteria as probiotics

“…After 28 days of storage, L. bulgaricus and L. acidophilus counts were greater compared to the non-supplemented yoghurts. Streptococcus thermophilus and Bifidobacterium animalis counts were not affected by supplementation.[88] Lactobacillus acidophilus Lactobacillus bulgaricus Streptococcus thermophilus Bifidobacterium lactis Bb-1272 children commenced and 70 children (36 placebo and 34 probiotic) completed the trial. There were no incidents of severe diarrhoea (stool consistency ≥6, ≥3 stools/day for ≥2 consecutive days) in the probiotic group and six in the placebo group (Fisher’s exact p = 0.025).…”