Potential antimicrobial activity of weak acids in combination with pH and temperature on Alicyclobacillus acidoterrestris

Alicyclobacillus acidoterrestris is a spore-forming, thermophilic and acidophilic bacterium causing spoilage in fruit juices and acid dinks. This research investigated the effects of various ascorbic, malic, citric, tartaric, and lactic acidson the growth and survival of two wild strains of A. acidoterrestris in interaction with pH levels (2, 3 and 4) and storage temperatures (5 and 45°C) over 2, 7 and 14 days.

The results show different impacts of weak acids on A. acidoterrestris growth and survival. Ascorbic and malic acids have the highest antimicrobial activity, leading to significant reductions in viable cell count; also, pH played a crucial role. Moreover, the results suggest a possible activity of acids on outgrowing spores rather than on spores.

The findings emphasize the significance of acid type and concentration, pH, and temperature conditions in determining the efficacy of weak acids against A. acidoterrestris. However, further validation in real food products is necessary to develop predictive models for effective control measures against this spoiling microorganism. Understanding the complexities of weak acid interactions with A. acidoterrestris in food systems is crucial for implementing preventive or corrective strategies in juice and acidic drinks industries to ensure product quality and reduce spoilage incidents.