Modeling thermal resistance and survival variabilities of Salmonella during conching and storage of chocolate

• Grant number: 17/00569-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2017
• End date: August 31, 2017
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Anderson de Souza Sant'Ana
• Grantee: Samuel Hiroyuki Kumazawa
• Host Institution: Faculdade de Engenharia de Alimentos (FEA). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

In foods such as chocolate, stress response mechanisms allow a survival of pathogenic microorganisms, e.g. Salmonella, and due to its fat content few cells are able to cause infection when the contaminated food is consumed. During cocoa processing, Salmonella contamination occurs mainly at the drying and fermentation stages. At later stages such as roasting and conching, even under application of processing conditions considered drastic (high temperatures), it is possible to observe survival of Salmonella. However, it is known that strains of Salmonella can present varied resistance to heat treatments carried out on low water activity substrates. The knowledge of the thermal resistance of Salmonella strains that circulates in any cocoa and chocolate producing country is extremely important for sizing a proper thermal processing and for adopting control measures aiming to avoid contamination of raw material. Nevertheless, there is no data on literature regarding variability of the thermal resistance of Salmonella strain. Additionally, another extremely relevant factor in studies involving pathogens in foods with low water activity is the recovery of the surviving microorganisms over time. Preliminary data obtained in our laboratory indicate that under osmotic stress conditions, there is great variability in the recovery of surviving microorganisms. However, this variability has not been characterized nor reported in literature. Thus, the objective of this study is to characterize a thermal resistance and variability in the recovery of different Salmonella strains from different serotypes during a stage of respectively conching and storage of the chocolate. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHAVES, RAFAEL D.; KUMAZAWA, SAMUEL H.; KHANEGHAH, AMIN MOUSAVI; ALVARENGA, VERONICA O.; HUNGARO, HUMBERTO M.; SANT'ANA, ANDERSON S.. Comparing the susceptibility to sanitizers, biofilm-forming ability, and biofilm resistance to quaternary ammonium and chlorine dioxide of 43 Salmonella enterica and Listeria monocytogenes strains. FOOD MICROBIOLOGY, v. 117, p. 8-pg., 2023-09-08. (13/27118-1, 18/15432-7, 14/03791-1, 17/00569-4)