Observations on the composition of milk-substitute products for treatment of inborn errors of amino acid metabolism. Comparisons with human milk. A proposal to rationalize nutrient content of treatment products

We tabulated and compared the stated compositions of four milk-substitute products, now in wide use for the treatment of various inborn errors of amino acid metabolism, and the known composition of human milk. Variations between the treatment products is great not only in the content of amino acids but also in minerals and vitamins, for example. Different source materials and rationales for their manufacture appear to explain these differences. All four products deviate in many ways from the composition of human milk. Although the existing treatment products are quite effective clinically, we propose that a more rational approach to the feeding of young infants whose nutrition is compromised by inborn errors of metabolism would begin with a synthetic product based on the composition of human milk that could be modified specifically to fit the needs and tolerance of the individual patient.

An evaluation of the phytate, zinc, copper, iron and manganese contents of, and zn availability from, soya-based textured-vegetable-protein meat-substitutes or meat-extenders

1. A study has been made of the zinc, copper, iron, manganese, protein (nitrogen X 6.25) and phytic acid contents of nineteen soya-bean-based textured-vegetable-protein (TVP) meat-extenders and meat-substitutes and of three "ready-prepared" canned meals containing TVP. 2. Phytate analysis was performed using a newly-developed method based on Holt's (1955) procedure. This method enabled the phytate content of milligram quantities of TVP to be estimated, with an SD for six replicates of 3%. 3. The Fe, Cu and Mn contents (mg/kg) of the meat extenders or meat-substitutes varied, with values of 59.4-144, 14.1-19.7 and 19.5-29.1 respectively. The protein content of these products was approximately 500 g/kg. 4. The phytate content of the meat-extenders and meat-substitutes ranged from 11.0 to 20.2 g/kg and the Zn content from 35.0 to 49.4 mg Zn/kg. The calculated molar ratio, phytate: Zn varied from 25 to 42. 5. The trace element, phytate and protein contents of the "ready-prepared" canned meals were 30-50% lower than the meat-extenders and meat-substitutes. 6. Cooking the "ready-prepared" meals as specified by the manufacturers was without effect on the trace element or phytate content. 7. When TVP was fed to rats as the only protein source, they had significantly lower growth rates and plasma Zn concentrations than rats given an egg-albumen-based diet of similar Zn content (14.5 mg Zn/kg). Supplementation of the TVP diet with Zn (100 mg Zn/kg) significantly increased growth rate and plasma Zn concentration whereas Zn supplementation of the albumen diet was without effect. 8. The possible implications of consumption of TVP products in relation to Zn status of the human population is discussed.

Effect of reconstitution on vitamins A and C content of whey-soy drink mix

The nutritive quality of a whey-soy drink mix was determined by measuring the retention of added vitamins A and C after the product was reconstituted in boiling water. In one study the mix was mixed in boiling water for up to 5 min and analyzed for vitamin content after each 1 min heating interval. The reconstituted product lost approximately 50% of the original vitamin content after being boiled for 1 min. Little further decrease in vitamin content was observed after several additional minutes of boiling until the 5-min interval when both vitamins dropped to about 35% of original amounts. In another study the mix was reconstituted by mixing the powder in boiling water for 20 s, then allowing the mix to stand at room temperature with no additional heating. This mixture decreased slightly in vitamin content when analyzed at 5 min intervals for up to 25 nin. For maximum vitamin retention whey-soy drink mix should be reconstituted by blending it in boiling water for about .5 min, then allowing the mixture to stand at room temperature before serving.

Determination of phytonadione in elemental diets by TLC-spectrophotodensitometry

The quantitative analysis of phytonadione in several elemental diet formulations at levels ranging from 90 to 150 ppb is described. After extraction with petroleum either, the sample is cleaned up by silica gel column chromatography and separated on a TLC plate; phytonadione is determined by reflectance densitometry. Recovery data show that the method is accurate (X = 97%) and has a precision (RSD) of +/- 6%.

Preparations used for the artificial feeding of infants

Cow's milk differs from human milk in a number of important ways, and manufactures of dried milk preparations for infants have used various methods to make the composition of the diluted product more like that of human milk. The first was to add lactose, or to recommend the mother to add sucrose. This not only increased the carbohydrate, but also 'diluted' the protein and inorganic constituents which are more concentrated in cow's than in human milk. The second was to replace all or part of the cow's milk fat with animal and vegetable fats, and so make the fatty acid composition more like that of human milk fat. In particular the proportion of linoleic acid was increased and that of stearic acid decreased, and this made the fat more easily digested and absorbed by the young infant. The third modification of cow's milk has been more fundamental. Its aim has been to make a product containing less sodium and phosphorus than cow's milk and with a higher lactalbumin: casein ratio. Whey, which contains lactalbumin but not casein, is used as the starting material. This is dialysed to remove soluble inorganic constituents. Some skimmed milk is then added to supply casein and some minerals, and the composition is adjusted as required with further minerals and vitamins. Lactose is added and a mixture of animal and vegetable fats. Dried milks on sale in Britain contain added vitamins A,D, and C and also iron. Some have added copper and zinc.

Determination of vitamin A in foods--a review

Formerly, few foods were routinely analyzed for vitamin A, but recent emphasis on nutrient requirements, nutrient labeling, and use of dietary convenience foods has created need for determining vitamin A in a variety of foods. There are many vitamin A methods--some suitable for certain products only. For regulatory purposes, the FDA specifies the AOAC method where it is applicable. However, some food analysts and organizations continue with their own vitamin A methods. If possible, a single, widely applicable general method should be used for vitamin A in foods. Vitamin A may be determined by spectrophotometric, colorimetric, and fluorometric procedures. Sometimes chromatography is required as an important part of the method. Colorimetric procedures with SbCl3 are now most widely used to measure vitamin A (retinol) in foods. If vitamin A content is high enough and extracts sufficiently free of interfering substances, spectrophotometric or flurometric methods are satisfactory. Methods in various stages of development for determining vitamin A in foods are based on flurospectrophotometry, gas-liquid chromatography, high-performance liquid chromatography, and automation. To estimate total vitamin A nutritional value of certain foods may also require determination of vitamin A isomerization and contents of carotenes, cryptoxanthin, reinaldehyde, and apo-carotenal.

Egg substitutes: use and preference--with and without nutritional information

Three egg substitutes, plus fresh and dried whole eggs, were evaluated by a consumer panel before and after receiving information on cost and caloric and cholesterol content of the products, and before and after sensory evaluations. Initially, most of the thirty panelists believed that the egg substitutes would cost the same or less than fresh eggs. After receiving information on cost and caloric and cholesterol content, the panelists perceived no significant differences in the nutritional value of the products. Fresh whole egg was the preferred product. After tasting, the consumers judged the nutritional value of all of the products higher, but their preferences were lower for all products except the fresh whole egg. Presentation of information on the caloric and cholesterol content of the egg substitutes without explanation of possible benefit in current health problems appears insufficient to change consumers' perception of a fat-modified product.

Egg substitutes: chemical and biologic evaluations

The total lipid, cholesterol, phospholipid, and fatty acid content of dried whole egg (DWE), a refrigerated liquid egg substitute, a powdered egg substitute, and a commercial egg yolk replacer (EYR) were compared. All substitutes contained less total lipid, cholesterol, and phospholipid than DWE. The powdered substitute contained only half the total lipid content reported by the producers and only a fifth of the cholesterol of DWE, while the percentage distribution of fatty acids was similar to that of DWE. The liquid substitute and EYR had fatty acid distributions similar to soybean oil. Rat growth and lipid response were compared for diets containing either DWE or a mixture of EYR and egg white. Both diets were fed with and without vitamin and mineral supplements. Rat growth response was greatest on the DWE diets, either with or without the supplements, was intermediate on the supplemented EYR diets, and was least on the unsupplemented EYR diets. The consumption of DWE-containing diets, when compared with the EYR-containing diets, caused greater liver weight, greater liver total lipid and total cholesterol content, and slightly higher serum cholesterol.

[Artificial macaroni. 2. Biological value of synthetic macaroni]

The authors determined (in vitro) the amino-acid composition and the enzymatic cleavage of protein and starch as well as (in vivo) the biological value of synthetic macaroni produced on the basis of casein, soybean protein and cotton-seed protein. The products based on casein and soybean protein have a great biological value. Cotton-seed protein has a toxic effect. The biological value of synthetic macaroni is mainly determined by the composition of the initial mixture. The processes of production and culinary processing exert no essential effects on protein content, amino-acid composition of the protein and enzymatic cleavage.

Protein value of two imitation milks. Chemical and biologic assays

Two imitation powdered milk products were compared with whole milk for both quantity and quality of protein. One product had comparable quantity of protein, but inferior quality, while the other had comparable quality but inferior quantity. Therefore, neither was equivalent to whole milk when a reconstituted serving of the product was calculated in terms of the U.S. RDA. However, a single serving of either product would constitute 10 per cent of the U.S. RDA for protein. Calcium contribution in terms of U.S. RDA would also be significant, but would not equal whole milk for these particular products. Thus ingredient composition varies widely for imitation milk products. These products were not evaluated for other nutrients, such as fats and vitamins.

Chemically defined diet in the treatment of kwashiorkor

Kwashkorkor is associated with malabsorption of energy and nutrients. Standard diets often initiate diarrhea and a high mortality is still prevalent. A synthetic monomolecular formula has been evaluated and compared with a standard diet in the early rehabilitation phase of 21 children with kwashiorkor. The formula group had significantly less vomiting and reached minimum weight faster than the group on standard diet. Weight gain and diarrhea were similar. The rise of albumin and BUN was faster on standard diet. A significant increase in haemoglobin was seen only in the formula group. A rise in body temperature after a meal was evident in most patients and significantly more pronounced in the formula group. The lower total nitrogen content of the formula may explain the observed slower rise in albumin and BUN but the ready utilization was indicated by the favourable weight changes as well as the rise in rectal temperature. As high energy per volume was desirable the formula was not diluted to isoosmolality. However, the high glucose concentration in the experimental diet probably caused some negative effects.

[Analysis of a synthetic onion aroma (author's transl)]

A complex mixture of compounds possessing an intensive aroma of onions is obtained, when propionaldehyde, propionaldehyde and acetaldehyde are treated with hydrogen sulfide and ammonia. Dihydrodithiazines, diethyltrithiolane, diethyl-methyl-1,3-dithiine and in small quantities diethyltetrathiane, dimethylthiophene, dipropyldisulfide, dipropenylsulfide, alkylpyridines, and the condensation products of aldehydes can be proved by the GC-MS-technic. The compositions of the synthetic onion aroma corresponds slightly with the composition of the natural onion aroma.

Marine fat fed to young calves. I. Content and distribution of fatty acids in ingested and excreted fat

Fish oils hydrogenated to melting points of 31–33 or 38–40°C were examined as fat sources in milk replacers, soya lecithin being used as an emulsifying agent. Analyses performed on gas and thin layer chromatography showed a total fatty acid content of 68.2 % in the lesser hydrogenated and 58.7 % in the more hydrogenated fat. As much as 89 % of the total fatty acids were found in the triglyceride fraction of the former, and 75 % in the latter.

Diglycerides and cholesterol were measured together. Although 11 % of the total fatty acids was found in this fraction in the more hydrogenated fat, diglycerides and cholesterol were completely absent in the lesser hydrogenated fat.

Eight different samples of faeces originating from a balance experiment with calves were extracted by a modified Folch method and also by the Stoldt method. Both methods yielded similar total lipid contents, but the Folch method gave a considerably higher yield of fatty acids, particularly the longer chained ones.