The effect of heating temperature on the stability of bacteriocins produced by Growol isolate lactic acid bacteria

¹ Department of Microbiology, Faculty of Medicine and Health Sciences, Universitas Muhammadiyah Yogyakarta, Indonesia
² Department of Agribusiness, Universitas Muhammadiyah Yogyakarta, Indonesia
³ Politeknik Pembangunan Pertanian Yogyakarta Magelang, Indonesia

^* Corresponding author: lilis.suryani@umy.ac.id

Abstract

Growol is a functional food resulting from fermented cassava which is made through a process of soaking in water. During the soaking process, fermentation occurs by probiotic lactic acid bacteria. The aim of this research is to determine the effect of heating temperature on the stability of the bacteriocin produced by lactic acid bacteria isolating Growol against Escherichia coli. This research method was a laboratory experiment, with several stages, namely: 1) making Growol using fermentation techniques, 2) isolating lactic acid bacteria from Growol, 3) isolating bacteriocins, 4) testing the stability of heating temperature on bacteriocin activity. The place of research was carried out at the Microbiology Laboratory, Faculty of Medicine and Health Sciences, Universitas Muhammadiyah Yogyakarta. The results of the research showed that the Growol isolate of lactic acid bacteria had microscopic characteristics of rod-shaped cells and was gram positive. Bacteriocin was able to inhibit the growth of E. coli ATCC 25922 with an inhibition zone diameter of 6.5 mm. The bacteriocin produced by the Growol isolate of lactic acid bacteria is stable against heating at a temperature of 40-121°C. The heating temperature does not affect the stability of the bacteriocin produced by Growol isolate lactic acid bacteria.