Quality characteristics of cold-dried beef slices

Comparative study of ultrasound application versus mechanical agitation on pork belly brining for bacon production

Pork belly brining is a time-consuming step of bacon production that needs to be studied and enhanced through suitable technologies. In this sense, this study aimed at evaluating the impact of ultrasound (US), mechanical agitation (AG), and static brine (SB) on the kinetics of water loss (WL), solids gain (SG), and salt content (SC) of pork belly during brining under different temperatures. Mathematical models were used to estimate mass transfer rates, equilibrium parameters, and thermodynamic properties. Peleg model was chosen as the most suitable model to predict the kinetics experimental data (Radj2 ≥ 0.979 and RMSE ≤ 0.014). The increase in the brine temperature increased WL, SG, and SC for all treatments. Nonlinear effects of temperature were observed for WL, SG, and SC, following an Arrhenius-type behavior. The assistance of ultrasound significantly enhanced the velocity of WL, SG, and SC by 32-56%, while AG improved by 18-39% both compared to SB. Brining was considered an endothermic and non-spontaneous process through the thermodynamic assessment. The increase in temperature and the AG and US processes accelerated the formation of the activated complex. The application of ultrasound was considered the most suitable technology to reduce the brining time. However, significant improvements can be obtained by mechanical agitation. Therefore, both methods can be used to reduce the time processing of pork belly aiming at accelerating the bacon production process.

Improving the quality and processing efficiency of beef jerky via drying in confined conditions of pre-stretching

Inspired by the mechanical enhancement of hydrogel via drying in confined conditions, we applied this strategy to beef jerky manufacture for improving the quality and processing efficiency. In our study, beef strips were pre-stretched and then dried in a tensile state, and the confined conditions were achieved by controlling the stretched strains from 20% to 120%. Compared with the sample dried freely, beef jerky dried in confined conditions of different pre-stretching strains exhibited improved quality based on texture and sensory analysis. Additionally, this method also enhanced processing efficiency by reducing approximately 50% drying time. The excellent sensory quality and good texture of beef jerky were obtained as the pre-stretching strain was 80%. Drying beef strips in confined conditions made muscle fibers tense and enhanced hydrophobicity of myofibrillar proteins, leading to a compact structure with high shear force and anisotropy, and rapid water loss in beef jerky. This facile and green method provides a promising route to enrich the existing technologies of jerky processing.

Mass transfer enhancement of tuna brining with different NaCl concentrations assisted by ultrasound

The influence of different NaCl concentrations (2.5, 5, 7.5 and 10% (w/w)) on the mass transfer kinetics of tuna during brining process with and without ultrasound assistance was evaluated. Results showed that an increase in NaCl concentration and the application of ultrasound accelerated the salt diffusion in the tuna muscle, and the highest yield was obtained in 5% brine concentration. Moreover, the kinetics parameters were significantly affected by the NaCl concentration and ultrasound application during brining. The values of the mass transfer kinetics parameters (k₁, k₂) for total and water weight changes decreased as NaCl concentration increased with and without ultrasound assistance during brining. In contrast, the higher the NaCl concentration, the higher the value of the salting kinetics parameters for salt weight changes. The application of ultrasound enhanced the salt effective diffusion coefficient (De) from 402.8% to 653.21% during the brining process, and the highest De was also found at 5% brine concentration. The application of ultrasound can improve the uniformity of salt distribution, enhance water holding capacity, reduce hardness and chewiness, but have no significant effect on color of tuna muscle.

Application of ultrasound-assisted vacuum impregnation for improving the diffusion of salt in beef cubes

The aim of this study was to investigate the effect of different vacuum impregnation (VI) conditions (Control, VI-250, VI-500, VI-750, US-VI-250, US-VI-500 and US-VI-750) on the salt gain (SG) and water gain (WG) kinetics of beef cubes. The cubes were immersed in brine solution (4 g NaCl/ 100 g solution) and salted at different levels of vacuum (250, 500 and 750 mbar) using VI method with and without ultrasound. The final moisture and salt contents of the cubes were 78.60% and 1.59%, respectively, and the samples were salted the fastest with US-VI-250. Five kinetic models were selected to evaluate the SG and WG kinetics, and Azuara model exhibited the best fit. In addition, the salt (D_s) and moisture (D_w) diffusion coefficients were in the range of 5.94-8.11 × 10^-9 m²/s and 5.17-8.64 × 10^-9 m²/s, respectively. It can be concluded that the ultrasound-assisted VI could shorten the brining time by improving the salt diffusion in beef cubes.