Showing papers by "John W. Erdman published in 1983"

Bioavailability of Trace Mineral Elements

Abstract: INTRODUCTION . . . . . .. """"""""", . . . . . . . . . . ,"',',"""", .,' 2 1 3 CHROMIUM"", ...... , .,"""', ., . . . . . . . . .. ,.,""', . . ,'"""', . . . . , .""""",., . . . . . . ,""""" 214 COPPER ,. ,' "", . .. . .. , ' ,"""', ., . .. ...... ,""" , . . . "", """", . ... ",.,"'" "" ., . '" """"" 215 MANGANESE,., .. ,"""""", . . . . , . .. ,"""""""""""',., .,', .,"""', .,""""""", . . . . 2 1 8 SELENIUM ",.,.,.,"""",., ...... .. ,"""""', .,"""", ."., .,', .,""', ." .,"""", .,"', . . , 2 1 8 ZINC .",,"""",.,""""""",.,.,"""""",.,"",.,"""",., ........ . ,", . . . ,', .,',"""'" 220 IRON."" ,"""",. , .""""""" ... ", '" """"", .. , ... ,""', . . , ," , ., ,""", .. ,"'" 223 CONCLUSION ... ,""',""" . . . ,""',""",., .. , .. ,,""", . . . .. """"""""""""""""" 226

Bioavailability of Zinc in Coagulated Soy Protein (Tofu) to Rats and Effect of Dietary Calcium at a Constant Phytate:Zinc Ratio

Abstract: An assay was conducted with young albino rats to compare the bioavailability of zinc contained in calcium- and in magnesium-precipitated tofu to zinc supplied as the carbonate in egg white diets. Relative availability of zinc from both tofu preparations was 51% as measured by weight gain and 36-39% for log micrograms tibia zinc accumulation. In a separate experiment with zinc supplied at 9 mg/kg in all diets, the effect of increasing dietary calcium on weight gain and tibia zinc accumulation was tested. Performance of tofu-fed rats relative to zinc carbonate-fed rats at 0.4, 0.7 and 1.2% calcium was, respectively: 92, 67 and 48% for weight gain, and 70, 58 and 61 for tibia zinc content.

Determination of lycopene, α- and β-carotene and retinyl esters in human serum by reversed-phase high performance liquid chromatography

Abstract: A rapid specific, microdetermination of the major human blood carotenoids by high performance liquid chromatography (HPLC) separation and quantitation at 466 nm is detailed in this paper. Serum retinyl esters can also be quantified utilizing the same separation procedure but detected at 325 nm. One hundred microliters of deproteinated serum were extracted with chloroform and injected on a reverse-phase column. Separation occurred within 16 min for all compounds of interest employing a mobile solvent of MeOH/AcN/CHCl3 (47:47:6). All compounds were quantified at the wavelengths cited by integrated peak areas using retinyl acetate as a daily standard. Analysis of serum from a hypercarotenemic anorexia nervosa patient and a person suffering from hypervitaminosis A are presented as examples of the clinical application of this procedure.

Effect of chronic alcohol consumption and moderate fat diet on vitamin A status in rats fed either vitamin A or β-carotene

Abstract: The effect of chronic alcohol consumption on vitamin A metabolism was investigated in male rats. Liquid diets containing five times the NRC requirement for vitamin A and varied levels of ethanol were fed. The vitamin A content of the liver was decreased in rats receiving alcohol. Liver lipids were only slightly elevated in alcohol-fed rats. Hepatic vitamin A storage was also decreased in rats fed 30% calories as alcohol and beta-carotene or vitamin A at the NRC requirement level, but not in rats fed one-sixth the NRC requirement as vitamin A. The activities of alcohol dehydrogenase, NADPH cytochrome c reductase, and retinol dehydrogenase were not altered in hepatic or testicular tissue by the vitamin A or alcohol content of the diet. When an intragastric dose of [3H]retinyl acetate or [14C]beta-carotene was administered, fecal excretion of radioactivity was lower than controls in rats receiving 30% ethanol in the diet for a total of 4 weeks, for 1 week following 7 weeks of control diet consumption, and after an acute dose of ethanol. Recovery of the 3H label was greater in the testes of rats chronically consuming ethanol. When a solution containing [3H]retinyl acetate or [3H]beta-carotene with or without ethanol was injected into intestinal segments, no alterations in absorption of retinyl acetate or beta-carotene due to ethanol occurred. It is concluded that alcohol consumption results in decreased hepatic vitamin A storage, which is not due to the malabsorption of either retinyl acetate or beta-carotene, or to altered activities of several enzymes involved in ethanol and vitamin A metabolism.

Effects of Calcium Addition on Stability and Sensory Properties of Soy Beverage

Abstract: Pasteurized or thermally processed soy beverages (6% soy solids) were fortified to a comparable level of cow's milk with 25 mM (or 30 mM) calcium using mixtures of calcium citrate and tricalcium phosphate. These fortified pasteurized products had acceptable sensory properties. Addition of these calcium salts did not adversely affect protein stability of the beverage. Calcium citrate addition caused a decrease in beverage pH and viscosity. Thermally processed (still retort and agitort) canned beverages containing calcium salts were stable for 6 months when stored at 1°C or at room temperature.

Laboratory scale production of winged bean curd.

Abstract: Procedures for the preparation of 100% winged bean or mixed winged bean-soybean curd employing the essential steps of soy curd production have been developed and optimized. Use of magnesium chloride, gluconodelta lactone, acetic acid and calcium sulfate as coagulants was investigated. The results showed that while curd formation was not facilitated by acetic acid, sticky and less cohesive curds could be formed with magnesium chloride and gluconodelta lactone. Calcium sulfate precipitation resulted in a semi-solid and appreciably cohesive curd from winged bean. Winged bean curd had very low hardness value in comparison to soy tofu. Curd products prepared from five ratios of winged bean-soybean mixtures indicate that 50:50 and 25:75 winged bean-soybean combinations by weight resulted in satisfactory products.