Environmental factors influencing the efficacy of probiotic bacteria.

Probiotic bacteria are not typical ingredients but rather living cells that can rapidly respond and adapt to changing conditions in their environment. Numerous factors from culture preparation and preservation, conditions in consumer product matrices, and genetic, dietary, cultural, and health differences between consumers can affect probiotic cell activity and probably influence the specific host-microbe interactions required for probiotic effects in the digestive tract. Understanding the impact of these factors on probiotic efficacy will aid in elucidating the molecular mechanisms of probiotic function, improve the design of probiotic-containing consumer products, and guide the establishment of standardized procedures for clinical studies intended to evaluate probiotic effects.