Abstract:
Beef jerky is a shelf-stable ready-to-eat dried meat product. In order to obtain
desired product characteristics, it is necessary to apply the appropriate drying process
in combination with adequate heat treatment, i.e. desired lethality time-temperature
combination sufficient for destruction of pathogenic microorganisms (“cooking
time”). In this study, the drying process with heat treatment was developed in
laboratory conditions using constant climate chamber, Model KBF 115 (BINDER
GmbH, Germany). The drying program was divided in two phases, lasting in total 6h
and 30min. During the first so-called cooking phase, the temperature in chamber was
70°C during the 2h and 15min. long period, while relative humidity ranged from 80%
to 93.4%, being ≥90% for at least 1h. Throughout the second phase, drying
temperature ranged from 60°C to 65°C, while the relative humidity was gradually
reduced from 70% to 35% in 4h and 15min. Efficiency of developed drying and
cooking process was verified by microbial analyses and determination of water
activity (aw), moisture-protein-ratio (MPR) as well as product yield. Pathogenic
bacteria such as Salmonella spp., Escherichia coli and Enterobacteriaceae were not
detected in any sample, as well as yeasts and molds. Water activity (aw) in final
products ranged from 0.786 to 0.814, being lower then recommended value (0.85) for
obtaining safe and stable jerky products (FSIS Compliance Guideline, 2014). Additionally, MPR was below recommended value (0.75:1), ranging from 0.61 to
0.66, and product yield was approx. 40.4%.
