Influence of aging time, temperature and relative humidity on the sensory quality of dry-aged Belgian Blue beef.

The objective of this study was to evaluate the effect of aging period (0, 3, 6 or 9 weeks), aging temperature (2 versus 6 °C at 75% relative humidity, experiment 1) and relative humidity (70 versus 90% at 2 °C, experiment 2) on the sensory traits, oxidative stability and proteolysis of Belgian Blue beef. For each experiment, eight loins (M. longissimus thoracis et lumborum) from four animals (left and right side) were assigned to one of the two treatments (n = 4). Results showed no further tenderization after three weeks of aging, whereas metmyoglobin formation and lipid oxidation increased until nine weeks of aging (P < 0.05). During the nine weeks of aging, atypical flavor, odor and flavor intensity was affected (P < 0.05). This was accompanied by an increase of small peptides and other nitrogenous compounds. Aging temperature and relative humidity had only a very limited effect on the quality traits.

Isothermal gelation behavior of myofibrillar proteins from white and red chicken meat at different temperatures.

This paper provides insights in the isothermal gelation behavior of white and red chicken myofibrillar proteins (CMP) at different temperatures (20 to 80°C) and the underlying aggregation mechanism, allowing understanding of structure formation in poultry products during thermal processing. At low temperatures (20 to 60°C), an increase in aromatic surface hydrophobicity (SoANS) was found, suggesting potential formation of hydrophobic interactions between CMP. At higher temperatures (60 to 80°C), high SoANS and a significant decrease in total sulfhydryl amount (SH-amount) strongly indicate the presence of hydrophobic interactions and disulfide bonding, resulting in aggregation, as suggested by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The elastic modulus G' after 60 min isothermal heating (G'60min) significantly increased at 70 or 80°C, depending on the type of CMP. Differences in G'60min between white and red CMP were rather small at low temperatures (20 to 60°C). However, at 70°C, white CMP reached higher G'60min compared to red CMP, while the opposite was observed at 80°C. Overall, for every temperature studied, SoANS and SH-amount of red CMP were higher compared to white CMP. The differences in G'60min, SoANS, and SH-amount between white and red CMP were probably due to different isoforms. The results may help to steer quality characteristics of poultry products through intelligent choice of processing conditions.