Nisin as a food preservative: physicochemical, sensory properties and antimicrobial activity in Mexican tomato sauce

Summary Biopreservation is a technique that utilises natural microbiota and antimicrobial products to extend the shelf life of food in a controlled manner. Nisin, bacteriocins, is used commonly in meat and dairy items and is acknowledged as safe by the FDA under the acronym GRAS. Tomato sauce is an essential component of Mexican cuisine but has a limited shelf life. Nisin (0.01%, 0.1% and 0.2%) was used as a preservative to preserve its physicochemical and microbiological properties. The results were compared with those of a control group (with no preservative) and a sample that used potassium sorbate (0.2%) as a preservative. The Mexican tomato sauces were stored at 4, 20 and 35 °C for 180 days to test their stability. The results indicated that the nisin‐preserved Mexican tomato sauces remained stable at all three temperatures for 180 days. In addition, the sauce preserved with 0.01% nisin was preferred by untrained panellists, as it maintained its desirable taste and texture. The sauces preserved with 0.1% and 0.2% nisin exhibited no significant changes in their physicochemical properties. However, after 150 days of preservation, there was a noticeable difference in the antimicrobial activity of the nisin‐containing sauces compared with the sauce with sorbate and the control sauce without any additives. Based on the product's unique characteristics and physicochemical, microbiological and sensory properties, nisin can serve as a natural preservative for Mexican tomato sauces.