Effect of drying air temperature and slice thickness on the physical and microbiological quality of dried beef

The aim of this study was to investigate the influence of cabinet drying air temperature (30-60 °C) and sample thickness (2.5-10 mm) on the quality attributes of dried beef. The physical (colour, rehydration ratio/RR and texture) and microbial quality of beef samples were evaluated using standard procedures. There was a significant decrease (P ≤ 0.05) in L*, a*, b*and chroma/C* colour values with increasing temperature and beef thickness, while change in thickness had no effect (P > 0.05) on the hue/H* colour attribute. The RR was higher at 60 °C for 5-10 mm thick samples and decreased (P ≤ 0.05) with increase in beef thickness. The firmness values increased with increase in temperature from 30 to 50 °C, decreased at 60 °C and were significantly lower (P ≤ 0.05) at 2.5 mm beef thickness. The total viable counts (TVC) and Staphylococcus aureus numbers in beef dried at 30 and 40 °C were higher than that of fresh beef, whereas drying at 60 °C significantly (P ≤ 0.05) reduced the microbial numbers.