Short communication: Survival of the characteristic microbiota in probiotic fermented camel, cow, goat, and sheep milks during refrigerated storage

Abstract

The objective of this study was to monitor the viability during storage of Lactobacillus acidophilus LA-5 (A), Bifidobacterium animalis ssp. lactis BB-12 (B), and Streptococcus thermophilus CHCC 742/2130 (T) in probiotic cultured dairy foods made from pasteurized camel, cow, goat, and sheep milks fermented by an ABT-type culture. The products manufactured were stored at 4°C for 42d. Microbiological analyses were performed at weekly intervals. Streptococcus thermophilus CHCC 742/2130 was the most numerous culture component in all 4 products both at the beginning and at the end of storage. The viable counts of streptococci showed no significant decline in fermented camel milk throughout the entire storage period. The initial numbers of Lb. acidophilus LA-5 were over 2 orders of magnitude lower than those of Strep. thermophilus CHCC 742/2130. With the progress of time, a slow and constant decrease was observed in lactobacilli counts; however, the final viability percentages of this organism did not differ significantly in the probiotic fermented milks tested. The cultured dairy foods made from cow, sheep, and goat milks had comparable B. animalis ssp. lactis BB-12 counts on d 0, exceeding by approximately 0.5 log10 cycle those in the camel milk-based product. No significant losses occurred in viability of bifidobacteria in fermented camel, cow, and sheep milks during 6wk of refrigerated storage. In conclusion, all 4 varieties of milk proved to be suitable raw materials for the manufacture of ABT-type fermented dairy products that were microbiologically safe and beneficial for human consumption. It was suggested that milk from small ruminants be increasingly used to produce probiotic fermented dairy foods. The development of camel milk-based probiotic cultured milks appears to be even more promising because new markets could thus be conquered. It must be emphasized, however, that further microbiological and sensory studies, technology development activities, and market research are needed before such food products can be successfully commercialized.

Short communication: Viability of culture organisms in honey-enriched acidophilus-bifidus-thermophilus (ABT)-type fermented camel milk

“…Only moderate changes, not exceeding 0.4 log 10 cycle, occurred in viability of bifidobacteria during the 35-d storage period. This finding is in agreement with earlier reports that the loss in viability of bifidobacteria up to 6 wk of storage is mostly less than 1 log 10 cycle (Abu-Taraboush et al, 1998;Gueimonde et al, 2004;Varga et al, 2014). Honey addition at a level of 5% resulted in an increase (P < 0.05) in survival rates of B. animalis ssp.…”

“…The viability of Strep. thermophilus is generally reported to be high (>8 log 10 cfu/mL) in fermented dairy foods stored refrigerated for up to 6 wk (Antunes et al, 2005;Varga, 2006;Varga et al, 2014). It is worth noting that the viable counts of Strep.…”

“…For instance, its vitamin C content can be as much as 10 times higher than that of bovine milk (Konuspayeva et al, 2010). The aforementioned compositional differences between camel and cow milks may influence the growth and viability of lactic acid bacteria and bifidobacteria strains commonly employed in fermented dairy foods (Varga et al, 2014).…”

“…Further dilutions were made as required. Microbiological analyses (i.e., enumeration of ABT culture organisms, yeasts, molds, coliforms, and Escherichia coli) were carried out as described by Varga et al (2014). The pH value of samples was determined at room temperature with a Jenway 3510 pH-meter and combined glass electrode (Keison Products, Chelmsford, UK) standardized with pH 4.00 and 7.00 standard buffer solutions (Merck KGaA, Darmstadt, Germany).…”

Determination of biogenic amines by high‐performance liquid chromatography (HPLC‐DAD) in probiotic cow's and goat's fermented milks and acceptance

“…During the first 10 days of storage, the probiotic strains are highly viable in both fermented milks (cow and goat) (Varga et al. 2014). At this stage, probiotics produce substances that may provide beneficial effects to human health (Kongo et al.…”