Assessment of Enterotoxin Production and Cross‐Contamination of Staphylococcus aureus between Food Processing Materials and Ready‐To‐Eat Cooked Fish Paste

Abstract

This study evaluated Staphylococcus aureus growth and subsequent staphylococcal enterotoxin A production in tryptone soy broth and on ready-to-eat cooked fish paste at 12 to 37 °C, as well as cross-contamination between stainless steel, polyethylene, and latex glove at room temperature. A model was developed using Barany and Roberts's growth model, which satisfactorily described the suitable growth of S. aureus with R(2)-adj from 0.94 to 0.99. Except at 12 °C, S. aureus cells in TSB presented a lag time lower (14.64 to 1.65 h), grew faster (0.08 to 0.31 log CFU/h) and produced SEA at lower cell density levels (5.65 to 6.44 log CFU/mL) compare to those inoculated on cooked fish paste with data of 16.920 to 1.985 h, 0.02 to 0.23 log CFU/h, and 6.19 to 7.11 log CFU/g, respectively. Staphylococcal enterotoxin type A (SEA) visual immunoassay test showed that primary SEA detection varied considerably among different storage temperature degrees and media. For example, it occurred only during exponential phase at 30 and 37 °C in TSB, but in cooked fish paste it took place at late exponential phase of S. aureus growth at 20 and 25 °C. The SEA detection test was negative on presence of S. aureus on cooked fish paste stored at 12 and 15 °C, although cell density reached level of 6.12 log CFU/g at 15 °C. Cross-contamination expressed as transfer rate of S. aureus from polyethylene surface to cooked fish paste surface was slower than that observed with steel surface to cooked fish paste under same conditions. These results provide helpful information for controlling S. aureus growth, SEA production and cross-contamination during processing of cooked fish paste.

In vitro and in vivo characterization of the antibacterial activity and membrane damage mechanism of quinic acid against Staphylococcus aureus

“…S. aureus is widely distributed in air, water, dust, and the waste of human and animals. Moreover, S. aureus can survive in different foodstuffs over a wide range of temperatures (10–45°C), pHs (4.5–9.3), and NaCl concentrations (up to 15%) (Tango, Hong, Wang, & Oh, ). These characteristics make it easy to facilitate the bacterial contamination of foods during the process of manufacturing, package, storage, and circulation.…”

“…Some conventional physical treatments have been applied to control and kill bacteria, including thermal inactivation, high pressure, and normal cooking (Shi et al, ). Although bacteria can be killed by these methods, the heat‐resistant enterotoxins can persist, leading to staphylococcal food poisoning, and some physical treatments can cause adverse effects on the food quality (Tango et al, ). In addition to the physical treatments, chemically synthesized preservatives, such as sorbic acid and sorbate, benzoic acid, and benzoate, are also applied in food industry (Calo, Crandall, O'Bryan, & Ricke, ).…”

Modeling for Predicting the Time to Detection of Staphylococcal Enterotoxin A in Cooked Chicken Product

“…The initial time (another expression of TTD) in that study was suggested to be predicted by using the threshold concentration of S. aureus and the established S. aureus growth model in milk. Tango et al ( 2015 ) also analyzed the S. aureus cell density and the time when the toxin could be detected under various temperatures in cooked fish paste. However, both of them didn't apply and validate this method in their article.…”

Comparative microbiological analysis of four different sea fishes collected from local market in Dhaka Metropolis

“…(Reij et al, 2004;Jelena et al, 2011). Previously several studies showed that some thermostable enterotoxin of Staphylococcus aureus and Escherichia coli would not destroy completely even after cooking of seafood or if the food cooked properly, due to improper handling recontamination can take place and consumption of this type of food causes severe food poisoning (Ayulo et al, 1994;Vieira et al, 2001;Omeo et al, 2005;Simon and Sanjeev, 2007;Beleneva, 2011;Tango et al, 2015). On the other hand, cooked-frozen fish are widely consumed by working people in their busy life.…”