“…Probiotic cultures are commonly used in the dairy industry, and some products produced during lactic acid fermentation such as lactic acid, diacetyl, and acetaldehyde could be associated with the loss of viability of added probiotic bacteria [12]. Probiotic lactic acid starters have been suggested to produce bacteriocin against probiotic bacteria and vice versa [13,24]. In general, the cell viability depends on the strains used, interaction between species present, culture condition, oxygen content, final acidity of the product, and the concentration of lactic acid and acetic acid.…”