The effect of temperature and Pasteurization time on Staphylococcus aureus isolates from dairy products

Abstract

A feasibility study of prepubertal and over mature aged local goat in relation to results of In Vitro growth culture to obtain additional M-II oocyte resources AIP Conference Proceedings 1908, 020001 (2017)

Molecular characterization of antimicrobial resistance genes on farms and in commercial milk with emphasis on the effect of currently practiced heat treatments on viable but nonculturable formation

“…Given that pasteurization time and temperature are not sufficient to destroy all Staphylococcus spp. producing enterotoxins, recommending treatment at 80°C for 20 min for complete elimination of those staphylococci may be required (Yaniarti et al, 2017). Furthermore, pasteurization has been described as a predisposing factor for VBNC creation in E. coli in milk and dairy products (Gunasekera et al, 2002).…”

“…High-temperature, short-time pasteurization is a validated heat treatment in the dairy industry that involves heating the milk to 72°C (161°F) for 15 s. The aim of pasteurization is to reduce the number of microorganisms present, including pathogens, to a level where they do not pose a major consumer health risk (Mullan, 2019). Although pasteurization eliminates the majority of viable bacterial cells in good-quality raw milk (i.e., that with low initial thermoduric bacterial counts), it may also stimulate the formation of bacteria that are viable but nonculturable (VBNC; Yaniarti et al, 2017). Commercial UHT processing sterilizes the milk, killing not only viable bacteria but the majority of endospores as well; UHT processing usually involves heating milk to >135°C for 2 to 5 s. As such treatment is bactericidal, the VBNC state is not likely induced by UHT processing of milk.…”

Staphylococcus aureus: significance, control and rapid detection across milk chain

“…Besides enterotoxins, other toxins like exfoliative toxin A and B, and toxic shock syndrome toxin, are also produced by S. aureus (Fagundes and Oliveira, 2004). Further, they possess many surface proteins, which initiate infection by sticking (adhesion phase) to the tissues; and a variety of enzymes, such as proteases, lipases, and hyaluronidases that allow the bacteria to enter (invasion phase) and destroy tissues and spread (evasion phase) to nearby tissues during the infection process (Yaniarti et al 2017;Maikranz et al 2020). Heat resistance, toxin production, biofilm formation, antibiotic resistances are among the many characteristics that contribute to pathogenicity of S. aureus.…”

“…Another study documented that the pasteurization parameters failed to eliminate S. aureus from different dairy products. Optimally, 80 o C/20 minutes is required to kill S. aureus in dairy products(Yaniarti et al 2017).S…”

Isolation and Assessment of Antibiotic Response Pattern of Heat Resistant Staphylococcus aureus from Milk

“…Temperatures higher than 46°C are not acceptable for majority of the strains, but some may grow up to 50 °C (Medveďová and Valík, 2012). However there are reports of isolation of heat resistant S aureus from different food samples (Beena et al, 2014;Montanari et al, 2015;Yaniarti et al, 2017). Pasteurization, the process of heating every particle of milk to at least 63 o C for 30min or 72 o C for 15sec or to any temperature-time combination which is equally efficient in approved and properly operated equipment is one of the major thermal processes the dairy industry relies on to assure the safety and quality of the milk.…”