Evaluation of Antimicrobials and Salt Replacers for Use in Low‐Sodium Dairy Products

Abstract

AbstractSalt replacers and antimicrobial agents may be required to maintain consumer acceptability and safety of low‐sodium dairy products. To determine which antimicrobials could potentially be effective in these products, this study evaluated the efficacy of eight commercial antimicrobials alone and in combination with six commercial salt replacers. Milk and low‐sodium cheese agar systems were used as the growth medium for screening. Antimicrobials with and without salt replacers were added to the agar systems. Then cocktails of Listeria monocytogenes, Salmonella or Escherichia coli O157:H7 were spread plated on the supplemented agar and observed for growth after 24 and 48 h at 35C. Fermentates C and D, lauric arginate (LAE), and lactoperoxidase inhibited growth of all pathogens on milk agar. No pathogen growth was observed in the cheese agar containing lactoperoxidase. Salt replacers decreased efficacy of the fermentates and LAE against Salmonella and E. coli O157:H7.Practical ApplicationsPressure has been put on the food industry to reduced sodium levels in food. Because reduction of salt from dairy products could change the microbial stability and flavor, alternative antimicrobials and salt replacers may be required. Many commercial antimicrobial systems and sodium replacer exist, but testing each potential combination in a specific food matrix is impractical. Through the use of model milk and cheese systems, eight antimicrobials and six salt replacers were screened for efficacy against selected pathogens. Four of the eight antimicrobials screened inhibited pathogen growth in the model systems. Findings also indicated that salt replacers can negatively impact antimicrobial efficacy. While variation in a product matrix can interfere with antimicrobial efficacy, these findings can be used to help guide selection of antimicrobials and salt replacers for use in dairy products.