RESUMEN
High pressure processing (HPP) of pre-rigor longissimus thoracis (strip loin) from prime and bull animals substantially decreased the shear force and improved consumer eating attributes of the final meat product. The improved tenderness in both prime and bull meat was associated with a lower myofibrillar fragmentation index and reduced calpain 1 activity which indicated the mechanism of tenderisation was different from that which occurred in chill aged meat. Light microscopy showed disruption to the fibre packing within the muscle and electron microscopy confirmed significant disruption of the Z discs and M lines and disappearance of the A lines. Thus, HPP is associated with a reduction in the structural integrity and strength of the sarcomeres. These effects were consistent in strip loins sourced from prime and bull stock. HPP also led to the movement of glycogen phosphorylase from the sarcoplasmic fraction to the insoluble myofibrillar fraction in all animals and this was associated with a higher pH at 24â¯h.
Asunto(s)
Músculos de la Espalda/química , Calidad de los Alimentos , Productos de la Carne/análisis , Industria para Empaquetado de Carne/métodos , Carne/análisis , Estrés Mecánico , Animales , Músculos de la Espalda/metabolismo , Músculos de la Espalda/ultraestructura , Calpaína/metabolismo , Bovinos , Culinaria , Femenino , Preferencias Alimentarias , Glucógeno Fosforilasa/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Masculino , Masticación , Microscopía Electrónica de Transmisión , Miofibrillas/química , Miofibrillas/metabolismo , Miofibrillas/ultraestructura , Nueva Zelanda , Sarcómeros/química , Sarcómeros/metabolismo , Sarcómeros/ultraestructura , Espectrometría de Masas en TándemRESUMEN
Currently, the exact role of telocytes within fascial structures is unknown. The morphology, distribution and behaviour of fascial telocytes as well as the mutual relationship between telocytes and other cellular fascia constituents should be definitely a subject of further studies. It will contribute to better understanding of the role of the fascial system in health and diseases, may shed light on the regeneration potential of these tissues and may help to find targets for future treatments for locomotor disorders, including fascial diseases. Last but not least, confirmation of the presence of telocytes within fascia may contribute to optimise the use of fascia as a graft material.
Asunto(s)
Músculos de la Espalda/ultraestructura , Fascia Lata/ultraestructura , Telocitos/ultraestructura , Músculos de la Espalda/metabolismo , Comunicación Celular , Tejido Conectivo/metabolismo , Tejido Conectivo/ultraestructura , Células Endoteliales/metabolismo , Células Endoteliales/ultraestructura , Fascia Lata/metabolismo , Fibroblastos/metabolismo , Fibroblastos/ultraestructura , Humanos , Mastocitos/metabolismo , Mastocitos/ultraestructura , Microscopía Electrónica de Transmisión , Miofibroblastos/metabolismo , Miofibroblastos/ultraestructura , Neuronas/metabolismo , Neuronas/ultraestructura , Regeneración/fisiología , Telocitos/metabolismoRESUMEN
The objective of this study was to evaluate the effects of electrical stimulation (ES) versus non-electrical stimulation (NES) and type of boning (hot versus cold) on the eating quality of Gannan yak longissimus lumborum. Eighteen Gannan yak bulls were randomly divided into two groups: ES and NES. Hot boning (HB) and cold boning (CB) were applied to the left and right side of the carcasses, respectively. All of the four treatments missed the "ideal" pH/temperature window. HB reduced the rate of pH decline, decreased meat tenderness and water holding capacity. ES increased the rate of pH decline and improved yak meat tenderness (P<0.05); however, ES explained only 1% of the variation in WBSF. HB and ES had no significant effects on cooking loss, L* or b* values of yak meat. Postmortem aging increased yak meat tenderness and improved meat color parameters. HB had negative effects on yak meat quality, while ES could not reverse these deleterious effects.