Proximate Analysis, Free Amino Acid, Vitamin and Mineral Content of Microwave Cooked Meat

Abstract

Beef, pork and lamb roasts were cooked by two 2450 MHz microwave ranges, one operated at 220V (1054W cooking power) and one at 1lSV (492W cooking uower) and by a conventional gas oven (163 f 3°C). The only significant effect related to power level of micrdwave ranges was retention of thiamine, riboflavin and niacin which was less in meat cooked by the micro\lave 115V than by the other two methods. There was a trend toward less retention of sodium, chloride, phosphorus and iron in meat cooked by microwaves than by the conventional method. Also, microwave cooking resulted in less formation of free amino acids than conventional cooking but total protein did not differ significantly.

Nutrient retention in foods after earth-oven cooking compared to other forms of domestic cooking

“…Retention of riboflavin in microwave cooked lamb chop samples was above 90% which was in good agreement with the retention values reported by Ang et al (1975) for cooking of beef by four reconstitutional methods. Retention values for microwave cooked lamb chops (97%) was slightly higher than the retention of 88% reported by Baldwin et al (1976) and 89.5% by Bowers and Fryer (1972) for microwave cooked lamb and turkey, respectively.…”

Nutrient retention in foods after earth-oven cooking compared to other forms of domestic cooking

“…Almost all previous researchers have found significantly more moisture to be lost by microwave cooking than by conventional cooking of meat (Janicki and Appledorf, 1974;Baldwin et al, 1976;Moore et al, 1980;El-Shimi, 1992). Except for the values in chicken skin and lamb fat, the content of moisture in microwave-cooked meat (chicken and lamb chops) was always lower than the moisture content of meat roasted in the oven.…”

“…Another reason could be the amount of dripping, which probably was proportionally more from the chicken, washing out more fat from the chicken than the lamb chops. Baldwin et al (1976) found that the percent fat in the drippings differed for pork and lamb cooked conventionally and by microwave. There seemed to have been no explanation for this difference in the trends between the two species of meat.…”

“…Previous researchers have shown nitrogen to be present in the drippings of cooked meat (Lang, 1970;Baldwin et al, 1976;Cross and Fung, 1982). Protein is lost into the drippings through the loss of collagen in the form of gelatin in the drip (Lang, 1970).…”

Free aromatic amino acids in egg yolk show antioxidant properties

“…Most of the amino acids, including aromatic amino acids, were significantly reduced in quantity during cooking; microwave cooking caused the highest losses in both type of samples (Table 4). A previous study on conventional and microwave cooking of pork, beef and lamb showed that most essential amino acids including leucine, isoleucine, phenylalanine and methionine were affected during cooking (Baldwin, Korschgen, Russel, & Mabesa, 1976).…”