Heat-treated Soybean Research Articles

Protected Methionine and Heat-Treated Soybean Meal for High Producing Dairy Cows

Twenty-four high producing Holstein cows (14 primiparous and 10 multiparous) were fed concentrate mix containing heat-treated soybean meal without or with 15g of added DL-methionine daily provided as 50g of ruminally protected methionine product during wk 4 through 16 postpartum. The 15% crude protein mixed diets contained 30% (dry matter basis) corn silage, 15% alfalfa hay, and 55% concentrate mix. Covariant adjusted yields of milk (34.6 and 33.1 kg/d), 4% fat-corrected milk (28.4 and 27.6 kg/d), and solids-corrected milk (29.0 and 28.5 kg/d) were not increased by feeding supplemental methionine. Percentages of fat (2.81 and 2.92) and protein (2.88 and 2.92) were similar, whereas total solids (11.49 and 12.69) and solids-not-fat (8.68 and 8.77) were higher with supplemental methionine. Dry matter intakes (20.2 and 21.0 kg/d) were higher when cows were fed supplemental methionine. Ruminal pH, volatile fatty acids, and ammonia as well as blood serum urea and glucose were generally unaffected by methionine supplementation. Concentrations of methionine in arterial and venous plasma were elevated slightly when additional methionine was fed. The first-limiting amino acid for milk production, methionine, was calculated by several methods and was not changed by feeding supplemental ruminally protected methionine.

Comparison of the Nutritive Value of Different Heat-Treated Commercial Soybean Meals: Utilization by Chicks in Practical Type Rations

Four commercially heat-treated soybean meals (Subnormal, Normal, Over, or Rumen Escape) were evaluated on the basis of their nutritive quality using proximate analysis, amino acid composition, in vitro tests (trypsin inhibitor activity, urease activity, protein dispersibility index, nitrogen solubility index), Hunterlab color values, and a chick bioassay. Each soybean meal (SBM) was incorporated into a practical-type broiler diet, formulated to contain 100% (Experiment 1) or 85% (Experiment 2) of the protein requirement.Compared to the Normal meal, excessively heat-treated SBM (Over or Rumen Escape) had lower crude protein (essential and nonessential amino acids); less trypsin inhibitor and urease activities; reduced protein dispersibility and nitrogen solubility indices; and was darker in color (redness). The nutritive profile of the Subnormal SBM was nearly identical to that of the Normal meal except that trypsin inhibitor activity, urease activity, nitrogen solubility index, and color scores (lightness and yellowness values) were reduced in the Normal meal due to processing. The protein dispersibility index was highest in the Normal meal, followed by the Subnormal, Over, and Rumen Escape.Performance data (body weight gain, feed conversion, relative pancreas weight) among broiler chicks fed either Subnormal, Over, or Rumen Escape SBM did not differ significantly compared to birds fed Normal SBM in Experiment 1 or Experiment 2. Moreover, supplementing diets containing Over or Rumen Escape heat-treated SBM with lysine (Experiment 2) did not significantly improve performance.These results indicate that the nutritive quality of commercially processed SBM should be assessed not only on the basis of in vitro tests but also on the basis of a chick bioassay.

Possibilities of using heat-treated full-fat soybeans in carp feeding

Full-fat soybeans were treated thermally (118°C) or hydrothermally (90–95°C), either gently (0.5 or 15 min) or intensely (2.5 or 30 min). They were flaked and then ground in a hammer mill. The trypsin inhibitor of the soybeans was more sensitive to hydrothermal treatment than was the urease activity. The content of available lysine was not affected by the type of treatment. The oil extracted from heat-treated soybeans, particularly from those treated hydrothermally, proved to be more resistant to oxidation than the oil from untreated beans. The heat-treated soybean meals were tested as feed components (50%) and compared with a protein equivalent fishmeal control diet in feeding experiments with carp. For body weight gain and body protein retention of the fish, the most favourable results were obtained with the gently and intensely hydrothermally or the intensely thermally treated soybean meals. However, only 60–65% of the potential of the fishmeal control diet was attained and a relatively higher body fat deposition could be observed. The possibility of improving the nutritional value of full-fat soybeans by amino acid supplementation is shown and is discussed in view of the documented high amino acid and energy availabilities of properly heated beans.

Amino Acids in Plasma and Duodenal Digesta and Plasma Growth Hormone in Cows Fed Varying Amounts of Protein of Differing Degradability

Eighty-four Holstein cows in early lactation fed diets varying in protein percent (11, 14, and 17% crude protein) and degradability in the rumen (normal and heated soybean meal) were sampled for effects on amino acids and growth hormone in blood plasma, and amino acid profiles in the duodenal digesta. Essential and branched chain amino acids in plasma increased as protein and amount of protected protein in the diet increased. These changes were accompanied by decreased concentrations of nonessential amino acids. Plasma growth hormone was highest at low protein (11.3%) probably because of decreased intakes on this diet. Molar percentages of amino acids in duodenal contents were not affected by diet suggesting that our heat-treated soybean meal influenced quantity more than quality of amino acids available for absorption in the small intestines.

Effect of Processing Temperature on Utilization of Whole Soybeans by Calves1,2

To evaluate utilization of processed whole soybeans by calves, in the first trial raw soybeans and soybeans processed at 138°C without tempering or 138°C with tempering, or at 171°C were evaluated in a nitrogen balance trial of four male Holstein calves 10 to 15 wk of age. Nitrogen retention was similar when calves consumed any of the heat-treated soybean diets but less for the raw soybean diet.In the second trial raw and processed soybeans were evaluated in an 8-wk growth trial of 96 Holstein day-old calves. Starters contained soybean meal, that with added fat, raw soybeans, or soybeans processed at 138, 171, or 191°C in a California Pellet Mill Jet-Sploder. Calves consuming the starters containing soybeans processed at 171°C consumed more feed, gained faster, had lower fecal scores (less scours), and less mortality.

Heat-Treated Soybeans for Lactating Cows

An experiment with 12 cows in switchback design determined the feeding value of a heat-treated soybean product. Treatments were regular soybean meal with 44% crude protein, commercially available heat-treated soybeans, and unheated soybeans. Concentrate mixes of protein sources and corn were formulated to contain 15% crude protein and fed at 1 kg/3kg milk. Forage portion of the diet consisted of 2.3kg alfalfa hay per day and corn silage ad libitum. Nitrogen solubilities of the protein supplement sources in 10% Burroughs’ buffer solution were 13.8, 9.4, and 25.4%, and averaged 29.4, 28.9, and 33.2% for the total rations. Cows averaged 7 wk postpartum at the start of the experiment, which consisted of three 4-wk periods. Production of milk was similar for all treatments. Means for cows fed soybean meal, heat-treated soybeans, and unheated soybeans were 28.6, 29.1, and 28.3 kg/day. No differences were in milk fat (3.57, 3.61, and 3.53%) or total solids (12.16, 12.12, and 12.13%). Protein percent in milk was lower for heat-treated and unheated soybeans (3.00, 2.92, and 2.93%), probably because of the higher fat content of those diets. Amounts of long chain unsaturated fatty acids in milk fat were higher for soybean diets. Heating soybeans improved their value slightly as a feed for lactating cows, but milk production by cows past peak production was not significantly greater than production with conventional corn-soybean meal diets.

Protein Solubility, Amino Acid Composition, and Biological Value of Regular and Heat-Treated Soybean and Sunflower Meals

Commercially available soybean and sunflower meals were subjected to moist heat in a cooker extruder. Heat treatment reduced solubility of nitrogen of soybean and sunflower in diluted Burroughs mineral solution 27 and 35%. Amino acid composition of the heated soybean and sunflower meals were similar to composition in the unheated meals. Essential amino acids tended to be slightly more insoluble than nonessential amino acids. Heat treatment tended to reduce solubility of all amino acids in soybean meal to about the same extent whereas the relative solubility of several amino acids differed substantially between sunflower meal and heated sunflower meal. Comparisons of essential amino acid compositions to the composition of milk indicated that methionine was the first limiting amino acid in soybean meal and remained first limiting in heated soybean meal as well as in the insoluble fraction of both meals. Lysine was first limiting in sunflower meal and its insoluble fraction but was second limiting after threonine in heated sunflower meal and its insoluble fraction. Growth rates of mice fed heated protein supplements were the same as those fed regular soybean and sunflower meals, indicating that the heat treatment did not reduce protein quality. This heat treatment may be an appropriate method for reducing the solubility of ration proteins in the cow's rumen and yet allowing the proteins to be digested and utilized in the intestines.

Heat-Treated Soybean Meal as a Protein Supplement for Lactating Cows1,2

Eighteen Holstein cows were used to evaluate the effect of heat-treated soybean meal on production and composition of milk in a 16-wk lactation trial. Cows averaged 9 wk postpartum when the trial started. Concentrate mixes containing 50% of crude protein from regular, solvent extracted or heat treated soybean meal were fed at 1kg per 3kg milk produced. Corn silage was fed ad libitum and alfalfa-brome hay at 2 to 3kg per head daily. Cows receiving heat-treated meal produced slightly more milk during the first 8 wk of the lactation period when protein intake was limiting than cows fed the extracted meal but not in the later part of lactation when protein intake by both groups was more than adequate. Percents of milk components, intakes of dry matter and gains in body weight were similar for both treatments. In a total-collection digestion trial, wk 7 and 8 of the lactation trial with six cows from each group, digestibilities of dry matter, nitrogen, energy, and fiber fractions were slightly higher for the heat-treated ration. There were no differences in rumen ammonia, volatile fatty acids, or blood urea nitrogen, although blood urea nitrogen was not elevated as much by heat-treated meal. Heat treatment of soybean meal did not alter the profile of amino acids in the arterial or venous blood serum of cows nor affect uptake of amino acids by the mammary gland.

Role of Coprophagy in Masking Dietary Deficiencies of Cystine in the Rat

When a diet containing raw soybean was fed to rats, there was an increase in the synthesis of pancreatic protein, presumably exocrine protein, as evidenced by an increased uptake of [35S]cystine. There was also an increased transsulfuration of methionine sulfur as indicated by labeled sulfur transformation from methionine to cystine. This same pattern of events was produced in rats receiving a casein-containing diet when 50 mg of crystalline trypsin inhibitor was administered by gavage. However, if coprophagy was prevented, the increased uptake of [35S]cystine and [35S]methionine transsulfuration under both dietary conditions was blocked. It was found that prevention of coprophagy was without effect upon these two processes if supplementary dietary cystine was provided or if a dietary protein source with adequate cystine, i.e., heat-treated soybean, was provided. It was concluded that by practicing coprophagy, sufficient fecal cystine was being returned to the upper intestinal tract to permit some synthesis of pancreatic exocrine protein and with this stimulation of synthesis, transulfuration could proceed. This assumes that the biosynthesis of cystine is dependent upon the availability of sufficient cystine to permit active protein synthesis. In another situation where cystine requirement is high, namely, the rapidly growing rat, a limited amount of cystine was fed by providing a 12% casein diet. Either supplementary cystine or methionine was provided and it was found that both amino acids gave optimal growth in conventional rats, but when coprophagy was prevented, optimal growth was achieved only with the cystine-supplemented diet.

Raw and Heat-Treated Soybeans for Growing-Finishing Swine, and their Effect on Fat Firmness

Raw and Heat-Treated Soybeans for Growing-Finishing Swine, and their Effect on Fat Firmness

The Effect of Pelleting on the Nutritional Value of Ground Soybeans for the Chick

THE poor availability of soybean oil in ground soybean s limits their usefulness as a source of energy as well as protein for the chick. In a previous study (Carew et al., 1961) ground soybeans had a metabolizable energy value that was only 86% of that which would be anticipated on the basis of the composition of ground soybeans. However, in this same study it was found that the availability of soybean oil in soybeans for chicks could be markedly improved by compressing cracked dehulled soybeans into very thin flakes prior to including them in diets for chicks. Flaked, heat-treated dehulled soybeans were found to be equal to equivalent amounts of soybean oil meal and soybean oil in their ability to promote growth in chicks and improve efficiency of feed utilization. Apparently, the maximum value from heat-treated soybeans as a poultry feed ingredient can be obtained only if a processing …

An in Vitro Method for Determining the Availability of Soybean Oil in Unextracted Soybean Products for the Chick

SOYBEAN oil is an excellent source of energy for chicks and also will stimulate growth rate when included in certain types of chick diets (Dam et al., 1959; Carew, 1961). Therefore it is desirable to study various means by which soybean oils may be easily incorporated into diets for chicks.Since soybean protein is the most widely used source of amino acids for poultry rations, unextracted soybeans, which contain approximately 20% soybean oil, offer a simple means of supplying most of the amino acids as well as the beneficial properties of soybean oil to chick diets in the form of a single feed ingredient.Previous reports from this laboratory have shown that finely ground, heat-treated soybeans do not serve as an efficient source of soybean oil for the chick because the soybean oil present in the soybean is poorly digested (Renner and Hill, 1960; Carew et al., 1961). Whereas extracted …

Liver xanthine oxidase activity in relation to availability of methionine from soybean protein.

SummaryXanthine oxidase activity in livers of rats consuming soybean protein was increased by feeding heat-treated soybean flour or by adding methionine to diets containing ther unheated flour. Since there was no difference in the degree to which the methionine was absorbed, it was concluded that heating increased the availability of methionine for the synthesis of enzyme protein. The poor growth on raw soybean flour was not entirely due to an impairment in the availability of methionine.

The site of nitrogen absorption in rats fet raw and heat-treated soybean meals.

The site of nitrogen absorption in rats fet raw and heat-treated soybean meals.