Beef muscle, lipid extraction from

Lipid Extraction from Muscle Tissues 3. 1. LIPID EXTRACTION FROM BEEF AND POULTRY MUSCLE... 

Supercritical COj (SC-CO2) was used to reduce the lipid of meat and the cholesterol of meat and beef tallow. Lipids can be removed quantitatively from dried muscle foods by SC-CO2, but relatively high temperatures are needed. The use of SC-CO2 in conjunction with ethanol, adsorbents and multi-separators also reduced the cholesterol of beef tallow. SC-CO2 was also used to concentrate volatile flavor compounds from beef and pork fat. The volatile components in various extraction fractions were identified and quantitated. 

Extraction of lipids from muscle foods is more predictable if the food has less than 10% moisture. Higb recoveries of glycerides can be obtained from dry meat products by extracting with SC-CO2 above 300 bar, but cholesterol is extracted less effectively. Cholesterol is extracted from beef tallow more efficiently at lower pressures than at higher pressures (<300 bar). 

Dehydrated beef [12] and chicken [13], which are used extensively in a variety of convenience products, were extracted since extraction of intact muscle presents difficulties due to its fibrous structure and high moisture. Lipid and cholesterol r uction of 95 and 89%, respectively, was achieved at 38.6 MPa/55°C with chicken chunks [13]. Lipids were more easily extracted from beef and chicken chunks than powders. Even though dehydrated chicken products (2.89 and 4.4% moisture in powder and chunks, respectively) were used, there was a further reduction in moisture content following extraction. Lighter color products with less redness were reported for chicken and beef [12, 13], which was due to extraction of pigments with SC-CO2. 

Four aspects of research involving the use of SFE for the improvement of quality of muscle food products are briefly discussed. These include supercritical CO2 extraction of lipids fi om fresh ground beef and from dried muscle foods the extraction and separation of lipid and cholesterol from beef tallow supercritical CO2 extraction of flavor volatiles from beef and pork lipids for use as additives in synthetic meat flavors and identification and quantitation of flavor volatiles extracted with SC-CO2. 

Most studies of SC-CO2 quantitative extraction of lipids from muscle foods have been limited to dried materials with moisture levels below 10%. King et aL (26), Froning (27) and Hardardottir and Kinsella (28) were able to quantitatively remove lipid from muscle foods and data for Aese studies are shown in Table I. This table also includes data from study of dried pork. Maximum removal of lipid from dried beef and luncheon meat was obtained at 300-345 bar/45-80 C (26, 27) and at 275 bar/80 C for trout (28). 

Use of ethanol as a co-solvent with SC-CO2 enhances the extraction of cholesterol from dried muscle foods. High extraction pressure coupled with multiple separation vessels for gradual reduction of SC-CO2 density reduces the separation time necessary for separating cholesterol from beef tallow using less CO2 than extractions at lower pressure. Ethanol is a good co-solvent used with SC-CO2 for separating cholesterol from other lipids in beef tallow. 

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