Abstract:
At present, in the industry sector chemical preservatives are mostly used to preserve food, which may have a long-term negative impact. Therefore, this study aimed to adopt bacteriocin, a substance that inhibits the growth of microorganisms and can be digested in the gastrointestinal tract of human beings as a bio-preservative for food.
The research started with the isolation of Lactic acid bacteria (LAB) from Thai fermented food and local fresh food. LAB was primarily screened and selected from the effectiveness of bacteriocin production using the agar-well diffusion technique. The selected LAB was subsequently used to test for the shelf-life extension of tofu, flat noodles and Thai rice noodles. Four pathogenic bacteria were added to the sample and monitored for growth at room temperature for 72 hours.
The results showed that LAB could be grouped into 464 isolates, LAB Code L.459 had the best ability to inhibit the growth of target pathogenic bacteria and preserve tofu and noodles. Additionally, an L.13 had the best ability to inhibit pathogenic bacteria in Thai rice noodles. When compared to the control samples, the shelf life extended for at least 48 hours. The experiment and positive control were not significantly different. Finally, when identifying strains of L.459 and L.13 by 16S rDNA, and the data were compared by BLAST, it was found to be similar to the genetic sequence of Lactobacillus plantarum at 99 Percent identity.