Kinetic and thermodynamic parameters of nisin thermoinactivation

Author(s)

de Almeida, Gabriel Moretti ^[1] ; Nobrega Mendonca, Carlos Miguel ^[1] ; Converti, Attilio ^[2] ; de Souza Oliveira, Ricardo Pinheiro ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Biochem & Pharmaceut Technol, Prof Lineu Prestes 580 Bloco 16, BR-05508000 Sao Paulo - Brazil

^[2] Univ Genoa, Dept Civil Chem & Environm Engn, Pole Chem Engn, Via Opera Pia 15, I-16145 Genoa - Italy

• Document type: Journal article
• Source: Journal of Food Engineering; v. 280, SEP 2020.
• Web of Science Citations: 0

Abstract

Understanding the thermal inactivation of biopreservatives in food matrixes is essential for their proper use in the food industry, enabling reduction of heating time and optimization of heating temperature. With this aim in mind, the effect of heat treatment on the activity and thermostability of commercial nisin from Lactococcus lactis was investigated. Residual activity tests performed for 90 min in the 70-86 degrees C temperature range at pH 3.0 demonstrated that bacteriocin thermoinactivation followed first-order kinetics. Low values of the inactivation rate constant (0.0089-0.0892 min(-1)) and high values of the decimal reduction time (25.8 <= D-value <= 258.4 min) indicated excellent nisin thermostability in the lower end of the investigated temperature range, but the thermal resistance constant (z-value) was only 15.4 degrees C, which pointed out poor thermoresistance at the higher end. Thermodynamic parameters estimated for nisin irreversible thermal inactivation were energy, enthalpy and Gibbs free energy of activation of 155.1, 152.2-152.3 and 83.5-86.6 kJ mol(-1,) respectively, and activation entropy of 188.6-192.5 J mol(-1) K-1. If on the one hand these results taken together confirm the thermostability of nisin as a biopreservative in use in the food industry, on the other hand suggest the importance of looking for new more thermostable antimicrobials to use in operations at higher temperatures. (AU)

• FAPESP's process: 19/19054-0 - Use of lactic acid bacteria for the production of probiotic dairy drinks and bacteriocins: application in the food and pharmaceutical industries
• Grantee: Ricardo Pinheiro de Souza Oliveira
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• FAPESP's process: 18/04385-8 - Construction of a pediocin-producing recombinant lineage from agroindustrial waste
• Grantee: Ricardo Pinheiro de Souza Oliveira
• Support Opportunities: Regular Research Grants