Resting of MAP (modified atmosphere packed) beef steaks prior to cooking and effects on consumer quality

Development of novel fortified beef patties with added functional protein ingredients for the elderly

The effects of clean label functional protein ingredients; pea protein isolate (PPI), rice protein (RP) and lentil flour (LF), at 3% and 7% inclusion levels on technological and shelf life parameters of beef patties were evaluated over 12days. Protein content in the RP7 treatment was higher (P<0.05) than controls, but did not differ significantly from PPI7 and RP3. No effects on moisture, fat or ash content were detected. LF addition reduced product hardness, cohesiveness, gumminess and chewiness compared with controls. RP-enriched and control patties were associated with lower lipid oxidation over storage than PPI- and LF-enriched patties. RP had a differential effect on (L*), (a*) and (b*) when compared with controls. Microbiological characteristics for all treatments were acceptable after 12days. Protein fortified beef patties with a softer texture and acceptable technological properties targeted for ease of consumption by older adults were produced in an attempt to reach dietary targeted protein requirements for this segment.

Biofilm formation, phenotypic production of cellulose and gene expression in Salmonella enterica decrease under anaerobic conditions

Salmonella enterica subsp. enterica is one of the main food-borne pathogens. This microorganism combines an aerobic life outside the host with an anaerobic life within the host. One of the main concerns related to S. enterica is biofilm formation and cellulose production. In this study, biofilm formation, morphotype, cellulose production and transcription of biofilm and quorum sensing-related genes of 11 S. enterica strains were tested under three different conditions: aerobiosis, microaerobiosis, and anaerobiosis. The results showed an influence of oxygen levels on biofilm production. Biofilm formation was significantly higher (P<0.05) in aerobiosis than in microaerobiosis and anaerobiosis. Cellulose production and RDAR (red, dry, and rough) were expressed only in aerobiosis. In microaerobiosis, the strains expressed the SAW (smooth and white) morphotype, while in anaerobiosis the colonies appeared small and red. The expression of genes involved in cellulose synthesis (csgD and adrA) and quorum sensing (sdiA and luxS) was reduced in microaerobiosis and anaerobiosis in all S. enterica strains tested. This gene expression levels were less reduced in S. Typhimurium and S. Enteritidis compared to the tested serotypes. There was a relationship between the expression of biofilm and quorum sensing-related genes. Thus, the results from this study indicate that biofilm formation and cellulose production are highly influenced by atmospheric conditions. This must be taken into account as contamination with these bacteria can occur during food processing under vacuum or modified atmospheres.