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H T Slover

Publications and source records attributed to H T Slover.

12 recordsLinked to original sources
PubMed1976

Relative autoxidative and photolytic stabilities of tocols and tocotrienols.

The relative stabilities of selected individual tocols and tocotrienols and of equimolar mixtures of either alpha- plus gamma- or alpha- plus delta- tocopherols were determined in methyl myristate and methyl linoleate during autoxidation and photolysis. Solutions containing 0.05% of the appropriate tocopherol(s) or tocotrienols were subjected to UV light (254 nm) or to a flow of 4.3 ml/min of oxygen, both at 70 C. Tocopherols (T) and tocotrienols (T-3) were determined by gas chromatography without preliminary separation or purification. Under photolytic conditions, stabilities in increasing order in methyl myristate were gamma-T-3 less than alpha-T-3 less than delta-T less than alpha-T less than gamma-T less than 5,7-T less than beta-T and in methyl linoleate were alpha-T less than alpha-T-3 less than or equal to gamma-T-3 less than or equal to beta-T less than or equal to 5,7-T less than gamma-T less than delta-T. A solvent effect on the initial rate of photolysis was observed for 5-methyl substituted tocols but not for the tocols with an unsubstituted 5-position or for the tocotrienols. Under autoxidative conditions, stabilities in increasing order in methyl myristate were alpha-T = alpha-T-3 less than beta-T-3 less than gamma-T-3 less than delta-T-3 less than gamma-T less than delta-T = beta-T and in methyl linoleate were alpha-T less than alpha-T-3 less than gamma-T-3 less than beta-T less than gamma-T less than delta-T. Tocopherols were much more stable during autoxidation in methyl myristate than they were in methyl linoleate. In mixtures, there was no significant protection of alpha-tocopherol by either gamma- or delta-tocopherol under any of the conditions used. However, alpha-tocopherol was highly effective in protecting gamma- and delta-tocopherols in methyl myristate during both photolysis and autoxidation and in methyl linoleate during photolysis. During autoxidation in methyl linoleate, alpha-tocopherol protection of gamma- and delta-tocopherols after 24 hr was slight tough measurable.

Chromatography, Gas↗
PubMed1976

Automated fatty acid analysis.

An automated system for the analysis of fatty acids is described. Samples dissolved in CS2 are automatically injected and separated by temperature programmed gas chromatography. Peak areas and retention times were measured by an electronic integrator, and recorded on punched paper tape. Peaks are identified and amounts calculated by an off-line computer program based on one or more internal standards. The system is designed for use with samples of at least 10 mug. Some of the problems adn limitations are discussed.

Autoanalysis↗
PubMed1975

Composition of diets containing 25 and 35 per cent calories from fat. Analyzed vs. calculated values.

In a dietary study conducted to evaluate the effects of low-fat, low-cholesterol diets on the reduction of blood lipids in man, meals were analyzed for proximate composition, ten vitamins, fourteen minerals and trace minerals, fatty acids, tocopherols, and cholesterol; Validity of the calculated nutrient composition of the diets was assessed by comparing calculated with determined values. Comparisons were also made of the determined values with 1974 Recommended Dietary Allowances. Analyzed values and those calculated from Agriculture Handbood No. 8 were exceptionally close, except for calcium; By analysis, on a per-kilogram basis, the 35-per-cent-fat-calorie diet more nearly met the Recommended Dietary Allowances for most of the nutrients than did the 25-per-cent-fat-calorie diet. However, on a per-1,000-kcal basis, there were few differences between nutrients in diets with the two levels of fat calories.

Cholesterol, Dietary↗
PubMed1975

Major fatty acids and proximate composition of dairy products.

Data are reported on the major fatty acids and moisture, protein, fat, lactose, and ash content of several important dairy products, including major cheeses, presently available to the consumer. Samples of milk products, cheeses, wheys produced in processing, and the original milks from which the products were made were obtained from dairy processing plants. Samples of cheeses were also obtained from retail markets in six geographic areas of the United States. Nonfat fluid whole milk contained amounts of protein, lactose, and ash similar to those found in fluid whole milk. The fatty acid distribution of milk fat was not appreciably altered by the processing employed for this study. Protein and fat values were quite constant among samples of each cheese. No lactose was detected in the ripened cheeses. Mean fatty acid patterns for the different cheeses were not appreciably different from each other. The butyric acid (4:0) in the cheeses showed the greatest sample variation. The cheeses did not contain appreciably different proportions of polyunsaturated fatty acids. Procedures for converting data on fatty acid methyl ester to fatty acids (free acids or triglycerides) as weight percentages of the food are presented.

Animals↗