Muscle color

Little is known about the intestinal metabolism and uptake of retinoids in fish. This is surprising since these processes have been well described in mammals (see reviews 16,64,88) and dietary carotenoids (used to enhance muscle color) can amount to 20% of the total cost of diets used in aquaculture. Few studies have considered the intestinal absorption of retinoids, although a study with juvenile sunshine bass (Morone chrysops x M. saxatilis) reported that retinol uptake appeared to be carrier mediated28, as is the case with mammals36. 

Bai et al. (2004) showed high-pressure treatment (700 MPa, 20 min) influenced sensory, microscopic, and textnral properties of cattle and mutton skeletal muscles. Color of the samples faded and extension decreased. A marked variation could be seen in the microscopic structnre of myofibrils. Furthermore, shrinkage of sarcomere and rednction in shear force was observed. Han and Ledward (2004) found that, in the case of beef muscle, hardness increased with increasing pressnre (200-800 MPa) at a constant temperature (up to 40°C), whereas the hardness decreased significantly with the application of pressnre (200 MPa) at higher temperatnres (60°C or 70°C). Accelerated proteolysis might be the major contributing factor to the loss in hardness of the beef sample. 

High-pressure treatment of vacuum-packed prawn extended its shelf life, although it did affect muscle color slightly, giving it a whiter appearance. The viable shelf life of 1 week for air-stored samples was extended to 21,28, and 35 days for vacuum-packaged samples, samples treated at 200 and 400MPa, respectively (Lopez et al., 2000). 

Genes are segments of chromosomes. Some of the genes are coded to give each animate species its characteristics (e.g., color and number of eyes, type of hair, muscle), and others are coded to produce the chemicals required for the organism to live (metabolism). 

The sacroplasmic proteins myoglobin and hemoglobin are responsible for much of the color in meat. Species vary tremendously in the amount of sacroplasmic proteins within skeletal muscle with catde, sheep, pigs, and poultry Hsted in declining order of sarcoplasmic protein content. Fat is also an important component of meat products. The amount of fat in a portion of meat varies depending on the species, anatomy, and state of nutrition of the animal. The properties of processed meat products are greatiy dependent on the properties of the fat included. Certain species, such as sheep, have a relatively higher proportion of saturated fat, whereas other species, such as poultry, have a relatively lower proportion of saturated fat. It is well known that the characteristic davors of meat from different species are in part determined by their fat composition. 

Fleischfarbe, /. flesh color, fleisch farbig, farben, a. flesh-colored. Fleisch-faser, /. muscle fiber, -faulnis, /. spoiling or putrefaction of meat, fleischfressend, p.a. meat-eating, carnivorous. Fleisch-gift, n. meat toxin, ptomaine, -guinmi,... 

Following massive crush injury, myoglobin released from damaged muscle fibers colors the urine dark red. Myoglobin can be detected in plasma following a myocardial infarction, but assay of serum enzymes (see Chapter 7) provides a more sensitive index of myocardial injury. 

Cytochrome c is a heme containing protein which occurs in muscle at lower concentrations than does myoglobin. It was demonstrated some time ago (18) that oxidized cytochrome c reacts with gaseous nitrite oxide to produce a nltrosyl compound. Recent work (19, 20, 21) has examined the reactions of cytochrome c with nitrite and the contribution of the product formed to cured meat color in considerably more detail. The general conclusion is that even at the pH normally encountered in meat, the reaction can take place in the presence of ascorbic acid but probably does not affect meat color because of the unstable nature of the reaction product and the low concentration. 

Se deficit Baltic Sea States, Northwestern Russia, middle Volga regions, south of East Siberia Low Se content in forage plants, 0.01-0.1 ppm Depressed glutationperoxidase activity. White-colored muscles... 

Danielle, nine years old when interviewed, enjoys playing the piano and recorder, and making colorful origami animals. Ordinarily even-tempered, Danielle experiences dramatic physical and emotional reactions from exposure to perfumes and other chemicals, and from eating certain foods containing additives and allergens. Her reactions include nosebleeds, muscle aches, headaches, crying spells and irritability. 

Textured Soy Proteins. Textured vegetable proteins, primarily textured flours and concentrates (50% protein and 70% protein, dry basis, respectfully) are widely used in the processed meat industry to provide meat-like structure and reduce ingredient costs (3-6, 9-10). Available in a variety of sizes, shapes, colored or uncolored, flavored or unflavored, fortified or unfortified, textured soy proteins can resemble any basic meat ingredient. Beef, pork, seafood and poultry applications are possible 03, 4-7, 15, 19) Proper protein selection and hydration is critical to achieving superior finished product quality. Textured proteins have virtually no solubility and, thus, no ability to penetrate into whole muscle tissue Therefore, textured soy proteins are inherently restricted to coarse ground (e.g. sausage) or fine emulsion (e.g. weiners and bologna) products, and comminuted and reformed (i.e. restructured) meat products. None are used in whole muscle absorption or injection applications (2-4, 6, 11). 

Fig. 9.21 In vivo images of MWCNTs-QDs (0.5 tg ml-1 in PBS) in mice injected at different body regions a) MWCNTs attached with CdSe/Zns quantum dots (emission of 600 nm) at middorsal location b) MWCNTs attached with CdSe/ZnS quantum dots at ventrolateral locations, the suspensions were diluted by PBS at various concentrations as indicated (A through E) c) MWCNTs attached with InGaP/ZnS quantum dots (emission of 680 nm, 0.25 jj,g ml-1 in PBS) in liver, kidney, and leg muscles. All images were taken successfully in 2 min under epi-UV illuminator with excitation of 435nm. (Shi et al. 2007). Published with permission from Wiley-VCH see Color Plates)...

Mechanisms of action. The tonus of vascular smooth muscle can be decreased by various means. ACE inhibitors, antagonists at ATI-receptors and antagonists at a-adrenoceptors protect against the effects of excitatory mediators such as angiotensin 11 and norepinephrine, respectively. Prostacyclin an-Ltillmann, Color Atlas of Pharmacology 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 

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