Meat fats

Food and kindred products Processing, packaging, shipping Meats, fats, oils, bones, offal, vegetables, fruits, nuts and shells, cereals... 

In water, the concentration of toxaphene considered safe for protection of freshwater life is conservatively estimated to lie between 0.008 and 0.013 pg/L for marine life, it is 0.07 pg/L. This is in sharp contrast to the current recommended drinking water criterion for human health protection of 5.0 to 8.8 pg/L. Similarly, residues in fish tissue in excess of 0.4 to 0.6 mg/kg wet weight may be hazardous to fish health and should be considered as presumptive evidence of significant environmental contamination, although fish may contain up to 5.0 mg/kg before they are considered hazardous to human consumers. Toxaphene criteria for human health protection — which range in various foods from 0.1 mg/kg for sunflower seeds to 7.0 mg/kg in meat, fats, and citrus fruits — also appear adequate to safeguard sensitive species of wildlife. 

It thus seemed that the origin of the various components in meat volatiles could best be established by analyzing irradiation-induced compounds in meat protein and meat fat separately. Accordingly, a 500-gram sample of meat, the same size of sample normally used in irradiation studies of whole meat, was separated into a protein, a lipid, and a lipoprotein fraction by means of a methanol-chloroform extraction of the fat. The dry, air-free, fractions were then irradiated separately with 6 megarads of gamma radiation in the manner used for whole meat. The analytical results (Table V) show clearly that mainly sulfur compounds and aromatic hydrocarbons are formed in the protein fraction, whereas mainly aliphatic hydrocarbons are formed from the lipid. The lipoprotein fraction produced, as expected, both aliphatic hydrocarbons and sulfur compounds. Only the lipoprotein fraction had a characteristic irradiation odor. 

Another class of lipid components formed by heating which contribute to meat flavor is the lactones, which are formed by the lac-tonization of y- and 6-hydroxy fatty acids. 6-Long chain (6-tetra-decalactone) lactones predominate. Lactones can also be formed by conversion of low molecular weight saturated fatty acids, aldehydes and alcohols during heating of meat fat (13). Larick et al. (14) found Cla-Ci, 6-lactones associated with more desirable flavor of beef... 

Pork fat contains more unsaturated fatty acids than beef and its linoleic acid content is double that in beef. Heat produced volatiles in red meat fats are listed in Table IV. The presence of pyrazines in the volatiles of beef fat is due to the presence of nitrogenous compounds in the fat amounting to 0.1-0.2%N, (Kjeldhal method). These compounds might be proteins, peptides, amino acids, and amine moities in polar lipids. Such compounds... 

Fatty acids are the building blocks of TAG. More than 90 percent of fatty acids have an even number of carbon atoms, and are in aliphatic chains ranging from 4 to 22 carbons in length. The major fatty acid synthesis pathway is production of stearic acid (18 carbons) after which separate desaturase systems introduce 1, 2, or 3 unsaturated (double) bonds. Additional enzymes become active in elongating the chain as needed. Shorter fatty acids also are produced. Trace amounts of odd-number carbon fatty acids are found in most fats, and also have been synthesized for research purposes. Microorganisms frequently produce odd-number carbon fatty acids, with heptadecenoic (17 carbon) acid a major component of Candida tropicalis yeast fat. Up to 8 percent C17 fatty acids have been found in milk and meat fats of ruminants (cattle, sheep, goats) and are of rumen microbe origin. 

Oleochemical A chemical derived from biological oils or fats. These oils can be derived from meat fat, wool and vegetables. They are used in detergents, cosmetics and explosives. 

Lipids are biological materials that are insoluble in water but soluble in nonpolar organic solvents. Here the term will be used interchangeably with acylglycerol, the primary component of animal lipids. These are classihed as either fats or oils. The former are predominantly solid at room temperature (24°C), and the latter are liquid. The depot lipids of animals are generally fats. The major animal fats (also termed meat fats) of contemporary commerce are produced from pigs Sus scrofa), in which case they are termed lard and rendered pork fat, from the fat of cattle Bos taurus) or sheep Ovis aries) and termed tallow, or from poultry (primarily chickens. Callus gallus) and termed poultry fat. Tallow... 

TABLE 11. Selected Characteristics of Meat-Fat or Meat-Vegetable Fat Shortenings (reprinted by permission of AOCS). 

A study on diet and colon cancer was reported by W. Willett s group (Willett et at., 1990) (Table 11.3). The study examined various components of the diet, such as fiber, fat, and meat. The fiber component was divid into cereal fiber and fruit fiber. The fat component was divided into meat fat, dairy fat, saturated fat, and unsaturated fat. The meat component was divided into beef, pork, and lamb, and into rare versus well-done Styles of cooking. The body mass index, as defined in the Obesity chapter, was also recorded. The study was part of the Nurses Health Study Cohort, which was inibated in 1976 and involved 121,700 female nurses. Every 2 years, the nurses filled in a questionnaire that asked about various risk factors for disease. The questionnaire asked, for example, about 61 foods and their frequency In the diet. The foods were chosen to allow epidemiologists to make broad statements regarding the component nutrients. 

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