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The aim of the study was to investigate quality and shelf life of beef meat cooked under sous vide conditions then extended refrigerated storage for 10 weeks. Biceps femoris (n = 6) from six to seven year old cows were treated with 2 g/L ginger powder (GP) containing zingibain or control (no injection) and were then cooked in sous vide conditions at 65 °C for 1 h or 8 h. Cooked samples were evaluated for physicochemical (pH, total water content, cooking loss, Warner-Bratzler shear force (WBSF), texture profile analysis (TPA), L*, a*, b* properties and thiobarbituric acid reactive substance (TBARS)), microstructure (scanning electron microscopy) and microbiological (Brochothrix thermospacta, Clostridium perfringens, Lactic acid bacteria, Listeria monocytogenes, Salmonella spp, and yeasts and moulds) quality after vacuum packing, cooking, then refrigerated storage at 4 °C for 0, 2, 4, 8 or 10 weeks. Physicochemical parameters were improved by GP treatment (P < 0.05) while there was no effect of storage time on WBSF, TPA or microstructure. The microbial quality of sous vide cooked meat in refrigerated storage appeared to be four weeks and oxidation shelf life of the cooked meat was found to be two weeks under refrigerated storage., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Meat tenderness is an important quality trait critical to consumer acceptance, and determines satisfaction, repeat purchase and willingness-to-pay premium prices. Recent advances in tenderness research from a variety of perspectives are presented. Our understanding of molecular factors influencing tenderization are discussed in relation to glycolysis, calcium release, protease activation, apoptosis and heat shock proteins, the use of proteomic analysis for monitoring changes, proteomic biomarkers and oxidative/nitrosative stress. Each of these structural, metabolic and molecular determinants of meat tenderness are then discussed in greater detail in relation to animal variation, postmortem influences, and changes during cooking, with a focus on recent advances. Innovations in postmortem technologies and enzymes for meat tenderization are discussed including their potential commercial application. Continued success of the meat industry relies on ongoing advances in our understanding, and in industry innovation. The recent advances in fundamental and applied research on meat tenderness in relation to the various sectors of the supply chain will enable such innovation., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The effect of thermal protein denaturation on the structure and quality of muscles of different fibre types is not well understood. Unaged masseter (100% type I fibres) and cutaneous trunci (93% type II fibres) muscles (N = 10) were assessed for their characteristics, protein denaturation, cooking loss, Warner- Bratzler shear force (WBSF) and shrinkage after heating at 50 °C - 85 °C with a rate of 5 °C/ min. Raw masseter had a higher pH, collagen and water content, shorter sarcomere, comparable fibre diameter, and shorter and wider fragments upon homogenization, than cutaneous trunci. In cutaneous trunci, at 55 °C - 60 °C, the lower transition temperature of myosin and the greater cumulative enthalpy resulted in greater cooking loss in muscle cuboids, and greater transverse, longitudinal and volume shrinkage in fibres and fibre fragments, than in masseter. Protein denaturation explained 71% variability in fibre fragment volume and 58% in cooking loss of both muscles, as well as 47% variability in WBSF of masseter., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study examines the effects of ageing (1, 14 days), cathepsin inhibition (No or Yes) and temperature (25-90 °C) on the shrinkage of fibre fragments from three bovine muscles (semitendinosus, biceps femoris and psoas major) during heating. Shrinkage was quantified using light microscopy images. Muscle fibres (except in psoas major) had greater transverse shrinkage, and less longitudinal shrinkage in aged than in unaged muscles at temperatures ≥60-75 °C. In addition, cathepsin inhibition during heating at ≥65-90 °C caused greater transverse shrinkage in semitendinosus fibres, and reduced longitudinal shrinkage for all muscles. At temperatures ≥75 °C, the longitudinal and transverse shrinkage of the fibres was correlated for all muscles. Ageing of biceps femoris increases volume shrinkage on a fibre level, and hence potentially cooking loss, while cathepsin activity in the semitendinosus reduces volume shrinkage. In conclusion, cathepsin activity and ageing influence the shrinkage that occurs during heating and these factors should be explored further to enable optimisation of thermal meat processing., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aim of this study was to investigate the permeability properties of synthetic polymeric materials and their influence on the quality of packed chilled pork. Barrier properties of biaxially oriented polypropylene (BOPP) coated with acrylic/polyvinylidene chloride (BOPPAcPVDC) and biaxially oriented coextruded polypropylene (BOPPcoex), were tested on three gases: oxygen, carbon dioxide and nitrogen at different temperatures: 4 °C, 20 °C, 40 °C and 60 °C. Coefficients of permeability, diffusion and solubility were determined. The quality parameters of vacuum packed fresh chilled pork stored under controlled temperature over a 21-day period were evaluated with physico-chemical, sensory and microbiological analyses. Results showed that BOPPAcPVDC film provided better protection for fresh pork than BOPPcoex film in terms of physico-chemical, sensory and microbiological attributes, due to its greater barrier behaviour, with smaller permeance data (q) (0.98 to 324 cm 3 /m 2 · d · bar) for BOPPAcPVDC, compared to BOPPcoex (227 to 6200 cm 3 /m 2 · d · bar), in the temperature range from 4 °C to 60 °C (p < .001). The shelf life of fresh pork packed in this film was doubled, from 7 to 14 days., (Copyright © 2019 Elsevier Ltd. All rights reserved.)