RESUMO
Objective: To study the amount of fat, cholesterol and fatty acid intake in China and provide the basic material for dietary guidance. Methods: Two areas were selected both in North and South China and each area included 3 provinces, or municipality or autonomous region. Three representative survey sites were selected in each province, or municipality or autonomous region. Dietary survey was conducted by the method of weighing and recording and cooking method was also recorded. The amount of food consumption was calculated as standard person (adult male, light physical activity). All foods were gathered as 12 kinds of foods, and each kind of food was cooked and then mixed. The content of fat and fatty acid was analyzed for 8 kinds of foods and the content of cholesterol was analyzed for 4 kinds of foods. The intake of fat, fatty acid and cholesterol per capita was calculated. Results: The amount of fat intake among North I, North II, South I, South II was 70.5 g, 46.5 g, 58.7 g, 71.0 g respectively and the amount of cholesterol intake was 329.6 mg, 128.5 mg, 400.9 mg, 306.0 mg respectively. The main source of dietary fat was from meat and vegetables. Egg was the main source of dietary cholesterol and meat and egg were both the main source of dietary cholesterol in south II area. About 90% of saturated fatty acid was palmitic acid and stearic acid and 90% of monounsaturated fatty acid was oleic acid. Linoleic acid was the principal n-6 polyunsaturated fatty acid and linolenic acid was the principal n-3 polyunsaturated fatty acid. The ratio of S∶M∶P in North I was 1∶1.1∶1, in North II was 1∶1.6∶1.3, in South I was 1∶1.6∶1.3 and in South II was 1∶1.5∶1. Conclusion: The amount of fat intake and fatty acid profile was quite different among different areas and the dietary guidance should be more pertinent The current cholesterol intake was more than dietary guidance in most areas. In addition to egg, meat was also an important source of cholesterol.
RESUMO
A simple spcctrophotometric method for determination of total rare-earth metals in food is presented. Weigh 5 gm of dry sample in a dish. After soaking the sample more than half an hour with 10 ml 3N H2SO4, evaporate to dryness on a hot plate and ash at 600℃. Dissolve the ash in 1 ml 6N HCl, and evaporate to dryness. Dissolve the residue in 2 ml water, and transfer it to a 10 mi-graduated tube. Wash the dish repeatedly with small amount of water. Transfer the washings to the same tube, and dilute to 10 ml with water. Pipette two portions of aliquots of 4 ml sample solution to two 10ml graduated tubes in which 2 ml of HCOOH-NH3 buffer (pH 3.7) is added. After mixing, add 1 ml each of 10% sulphosalicylic acid solution and 5% ascorbic acid solution. Make volume to 8 ml with water. Mix thoroughly. After 10 minutes, add 1 ml 15% alcoholic diphenylguani-dine solution, mix and add 1 ml 0.025% arsenazo Ⅲ &K solution. Mix, and measure the optical density at 680, 660 and 640 nm against a reagent blank solution. Calculate the total rare-earth metals content with a calibration curve. The sensitivity of the method is 0.01 ?g/ml and the detection limit is 0.05ppm (5 gm of sample). The average recovery of added TRExOy is 91.9% (n = 14).