Muscle microstructure

Mikel, W.B., Goddard, B.L., and Bradford, D.D. 1996. Muscle microstructure and sensory attributes of organic acid-treated beef strip loins. Journal of Food Science 61 1058-1061. 

Development of the microscope by Anton van Leeuwenhoek (1673) and others, enabled man to see a new world of microcreatures. including bacteria, yeasts, molds, blood cells, and spermatozoa, and microstructures such as muscle fibers and plant and seed tissues. This added credibility to later claims by Louis Pasteur and Robert Koch that microorganisms can spoil foods and cause disease at a time when many influential learned men still clung to theories of spontaneous generation of life. 

The description of structure in complex chemical systems necessarily involves a hierarchical approach we first analyse microstructure (at the atomic level), then mesostructure (the molecular level) and so on. This approach is essential in many biological systems, since self-assembly in the formation of biological structures often takes place at many levels. This phenomenon is particularly pronounced in the complex structures formed by amphiphilic proteins that spontaneously associate in water. For example myosin molecules associate into thick threads in an aqueous solution. Actin can be transformed in a similar way from a monomeric molecular solution into helical double strands by adjusting the pH and ionic strength of the aqueous medium. The superstructure in muscle represents a higher level of organisation of such threads into an arrangement of infinite two-dimensional periodicity. 

Tn view of the complicated microstructure of the muscle fiber one would - expect that formation of ice crystals within the very small cavities would cause some damage to various cellular elements. A point of particular interest is "What influence does freezing of muscle tissue have on the sensitive membranes associated with mitochondria, the sarcoplasmic reticulum, lysosomes, and other subcellular particles In order... 

The basic component of meat is muscle tissue, which has a complex microstructure. Individual myofibers are surrounded by connective tissue membranes (endomysium) and bundles of myofibers are separated from each other by another connective tissue membrane, the perimysium. Muscle also contains veins, arteries, and nerve fibers. Skeletal (or striated) muscle differs in microstructure from the smooth muscle that is present in internal organs such as... 

From everyday experience of conventional materials, we may come to expect that disordering of a microstructure will always lead to a loss of reinforcement and a reduction or even failure of load-bearing ability. In fact, this combination of cause and effect has some notable exceptions, none more significant than the contractile mechanism of muscle (Pollack, 1990, 2001). 

Montejano, J.G. Hamann, D.D. Lanier, T.C. Thermally induced gelation of selected comminuted muscle systems Rheological changes during processing, final strengths and microstructure. J. Food Sci. 1984, 49, 1496-1505. 

Forceful static or repetitive muscle contractions lead to the compression of the vascular microstructures, changing the blood supply of the involved tissues (Kumar, 2001). Several studies have related the presence of WRMD and disturbances in blood flow (Pritchard et al., 1999, Brunnekreef et al., 2006, Gold et al., 2010). 

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