Growth of Pseudomonas fluorescens in modified atmosphere packaged tofu

Abstract

Aims: The objective was to study the growth of Pseudomonas in a food product (tofu) where it typically occurs as a spoilage organism, and when this product is stored under modified atmosphere. Methods and Results: A Pseudomonas strain was isolated from the endogenous microflora of tofu. Tofu was inoculated with the strain, packaged in different gas conditions (air, 100% N2, 30% CO2/70% N2 or 100% CO2) and stored under refrigerated conditions. Microbial loads and the headspace gas composition were monitored during storage. Conclusions: The strain was capable of growing in atmospheres containing no or limited amounts of oxygen and increased amounts of carbon dioxide. Even when 100% CO2 was used, growth could not be inhibited completely. Significance and Impact of Study: In contrast to the general characteristics of the genus Pseudomonas (strictly aerobic, highly sensitive to CO2), it should not be expected in the food industry that removing oxygen from the food package and increasing the carbon dioxide content, combined with cold storage, will easily avoid spoilage by Pseudomonas species. Guarantee of hygienic standards and combination of strategies with other microbial growth inhibiting measures should be implemented.

Dynamic changes of the bacterial communities in roast chicken stored under normal and modified atmosphere packaging

“…() showed that in 30% CO 2 /70% N 2 MAP, some Pseudomonas strains could grow in large quantities in tryptone soy broth. This result is also similar to that of Stoops, Maes, Claes, and Van () who studied the growth of Pseudomonas fluorescens in tofu stored in MAP. By 28 days of storage in MAP, Pseudomonas remained the main spoilage organism in roast chicken, and its relative abundance increased by approximately 40%.…”

Microbial community assessment of mealworm larvae ( Tenebrio molitor ) and grasshoppers ( Locusta migratoria migratorioides ) sold for human consumption

“…Both insect species were also colonised by OTUs representing members of Pseudomonas. Pseudomonads are important spoilage organisms in meat, fish, eggs, milk, vegetables and tofu (Masson et al, 2002;Stoops et al, 2012). Results of the culture-independent analyses showed that fresh insects contained a variety of potential spoilage bacteria.…”

Pseudomonas fluorescens: a potential food spoiler and challenges and advances in its detection

“…P. fluorescens isolated from sea bream stored aerobically in Greece market at 0°, 10°, and 20°C and modified-atmosphere packaging (MAP) conditions (40% CO 2 -30% N 2 -30% O 2 ) (Tryfinopoulou et al 2002). An investigation in Belgium has confirmed Fasolato et al (2018) NS not specified the growth of P. fluorescens in tofu packed in modified conditions and showed that some strain can survive under 100% CO 2 (Stoops et al 2012). The postpasteurization contamination (PPC) of high temperature, short time-pasteurized fluid milk with P. fluorescens continues to be an issue with processor defects like lower flavor scores, coagulation, and fruity fermented milk (Reichler et al 2018).…”