Content in dairy products

Comparative studies by Forss and co-workers (1960A.C) on the fishy, tallowy, and painty flavors of butterfat tended to emphasize the importance of the relative and total carbonyl contents in dairy products with different off-flavors. These researchers showed that three factors distinguished painty and tallowy butterfat from fishy butterfat. First, there was a relative increase in the n-heptanal, re-octanal, n-non-... 

A reversed-phase HPLC method was used for determination of cholesterol in dairy products, it evaluated that a more complete evaluation of cholesterol contents in dairy products is necessary when the vegetables and fruits are present. 

Some food items have a high iron content (e.g., blood sausage, meat and fish), while the iron content in dairy products, cereals, vegetables and fruits is comparatively low (see Table 13.1-1). In Germany, an average two-thirds of iron intake is accounted for by foodstuffs of animal origin (Anke 2001). 

Reliable data on the cholesterol content of dairy products, lacking in the past, are now available (LaCroix et al 1973). The amount in whole milk fat was 13.49 1.01 mg per 100 g milk which contained 3.47 0.74 g of fat. Data were obtained from 27 kinds of products, and from these an equation was derived for estimating the cholesterol content of dairy products with fat contents greater than those of whole milk. It is obvious that more fat is accompanied by more cholesterol, e.g., Cheddar cheese contains 102 mg/100 g, an approximate 8fold increase over whole milk. 

Hegarty, R V. J. 1981. Some practical considerations in the nutritional evaluation of the mineral content of dairy products. Ir. J. Food Sci. Technol. 5, 157-163. 

When reviewing Exhibit 1, it can be seen that every dairy product had detectable levels of at least one banned pesticide, whereas 13 dairy products had at least two or more detected banned pesticides. Clearly, the higher the fat content of the dairy products, the greater the number of the banned pesticides. Another common group of pesticides in dairy products are the endosulfan pesticides. Because endosulfan pesticides are a common contaminant in most agricultural products, its occurrence in dairy products (i.e., found in 10 out of 19 products) is expected. 

The discovery of health benefits of CLA and a recognition of the potential of RA as a functional food component in dairy products has stimulated research to identify factors that affect the CLA content of milk fat. These... 

Forss et al. (1960a,c) compared the qualitative and quantitative distribution of carbonyl compounds in dairy products with fishy, tallowy or painty off-flavor. Total content of volatile carbonyl compounds was approximately 10 times greater in the tallowy and 100 times greater in the painty butterfat than in fishy butterfat. Tallowy butterfat contained greater amounts of -heptanal, -octanal, -nonanal, 2-heptanone 2-heptenal and 2-nonenal, while painty butterfat contained greater amounts of K-pentanal and C5 to C10 alk-2-enals. 

Although significant strides have been directed at reducing fat content in food products, certain lipid ingredients and sources of fatty acids are used to enhance the health and nutritional quality of foods. For example, CLA isomers were enriched in both dairy and nondairy products to convey its anticancer and antiobesity effects that were reported repeatedly in animal studies (39). Sources of n-3 PUFAs are also added directly to infant formula to provide sufficient DHA for normal development of the nervous system during early infancy. In the United States, DHA was approved by the FDA in 2001 to be added into infant formula (40, 41). 

Before the 1990s, there were few options to standardize milk remove or add fat as cream, add casein as NDM, evaporated milk, or condensed milk [127]. Although to a lesser extent than fat content, the protein content of fluid milk also exhibits considerable natural variability worldwide. This variability is significantly magnified in dairy products that are manufactured by water removal, such as skim milk powder [128]. The International Dairy Federation (IDF) interprets protein standardization to imply relatively small changes in protein content, within the limit of natural variability, that are achieved by the addition or removal of natural milk constituents without altering the natural ratio of whey protein to casein [128]. 

Figure 47.3 Nosological types of hyperthyroidism with different iodine intake levels. Relative frequency of the four most common nosological types of hyperthyroidism in Iceland, with relatively high iodine intake from consumption of fish and high iodine content of dairy products, and from East Jutland, Denmark, with mild-to-moderate iodine deficiency. MNTG, multinodular toxic goiter GD, Graves disease STA, solitary toxic thyroid adenoma SAT, subacute thyroiditis. Data from Laurberg et al., (1991).

Despite the reduction in iodine content of dairy products, the contribution of these foods to the total iodine intake in the 2003-2004 NZTDS was still high, with 34% of the intake of a young male and 67% of that of a 1—3-year-old child (Vannoort and Thomson, 2005). A comparison of concentrations in corresponding foods analyzed for the 2003—2004 NZTDS (Vannoort and Thomson, 2005) with early values produced by Hercus and Roberts (1927), indicates that the only foods that show higher concentrations are cheese and milk as a result of iodophor contamination, and eggs as a result of trace mineral supplementation of poultry feed (Table 129.1). 

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