摘要:

AbstractAn agent depressing thyroid function present in soya beans has been described. It is soluble at pH 4.2, in 2 vol. of acetone and 10% trichloroacetic acid and insoluble in 90% acetone, 90% ethanol and in ethyl ether. It is not precipitated by saturated ammonium sulphate and resists pancreatic digestion and boiling for 2 h, but is apparently destroyed by autoclaving. Evidence of its small molecular weight includes its dialysability and retardation on a Sephadex G25 column. It decreases iodine uptake by the thyroid gland and its incorporation into the diet increases the tri‐iodothyronine‐binding capacity of rat se

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230502

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe application of anin vitrotechnique for the routine determination of digestible organic matter (d.o.m.) on comparatively large numbers of dried silage samples is described using a drying technique found to be superior to previous routine drying methods. Results are given of a study of the effect of drying the fresh silage at different temperatures prior to the determination of the digestible organic matter. A close correlation has been obtained between the d.o.m. values on fresh silage and those on material dried at 85 °C for 18 h, but the correlation is unsatisfactory with silage dried at 100 °

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230503

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractFlours of wheat, rye, barley, oats, maize and sorghum have been extracted to remove albumins, globulins and prolamins. The SS bonds of the starch‐glutelin residues (4 to 8% protein) have been reduced with sulphite and titrated with phenyl mercury acetate (PMA) in the presence of 3M‐guanidine hydrochloride at 37 °C and, in its absence, at 2 and 37 °C. Attention has been paid to several possible sources of error including oxidation and the rate of diffusion of PMA into protein particles. Approximate values for the diffusion coefficients of PMA through cellulose and protein films were obtained. Titrations at 37 °C in the absence of guanidine hydrochloride are unsatisfactory due to reaction of intrachain SS links. Evidence in the literature suggests that the SS bonds titratable at 2 °C are inter‐chain, possibly includingsomestrained intra‐chain bonds. The results imply that most of the major polypeptide chains in the cereal glutelins examined, apart from barley and sorghum, contain two such bonds. In the case of barley glutelin probably less than half the chains have two labile SS bonds. Most of the chains in sorghum glutelin appear to have a single labile bond and the polymers may contain only a few chains. The molecular weights (in thousands) of the principal polypeptide chains of the glutelins, deduced from gel electrophoresis in sodium dodecyl sulphate (SDS), are: Cappelle‐Desprez wheat 44, 41; Manitoba wheat, rye and barley, 44; oats, 33, 23; maize, 23, 19; so

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230504

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe chemical composition (moisture, ash, protein and non‐protein N, amino acids, ether extract, crude fibre, Ca, P, Fe) and biological quality (protein efficiency ratio and available lysine) were investigated in two batches ofCandida utilis(Torula yeast). The samples (S1and S2) were collected from a local factory. S2was sterilised before drying. Protein, mineral and B‐complex vitamin contents were comparatively high. Amino‐acid analysis showed a high content of lysine and threonine, but a deficiency in sulphur amino acids. The biological quality measured as the protein efficiency ratio (p.e.r.) and available lysine gave values of 1.80 ± 0.05 and 6.6 g/100g of crude protein, respectively, in S1. These are higher than values reported in the literature. Sterilisation (S2) and storage for 1 year (S1(a)) significantly reduced the biological quality of the protein (p.e.r. 1.15 ± 0.12 and 1.34 ± 0.07, respectively). Supplementation ofC. utiliswith 0.3%DL‐methionine increased the p.e.r. value to 2.77 ± 0.03, close to that of casein.C. utilisappears to be a valuable material for human diets because of the high content and satisfactory quality of its protein and othe

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230505

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractA method has been developed for the extraction, isolation and quantitative estimation of the total glutathione content of one‐g samples of flour.Graphs are presented showing the relationships obtained between total glutathione in flour and rheological properties of the resulting dough. It is concluded that endogenous glutathione in flour is an important determinant of dough's rheological propertie

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230506

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractDigestibility and nitrogen balance trials were carried out with sheep to investigate the action of a commercial food additive, desiccated glandular tissue, on the digestion of hay and mixed hay and barley diets. Use of the additive led to small increases in the apparent digestibility of dietary organic constituents including crude fibre, nitrogen and, in some diets, ether extract.In a second series of experiments with rumen‐cannulated sheep the effects of the additive on rumen fermentation were examined using a variety of diets. Supplementation of the diet, in most instances, was associated with an increase in rumen pH and in the proportion of butyric acid in the mixture of short‐chain fatty acids in the ru

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230507

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe main volatile product during the early stages of the autoxidation of α‐farnesene is 6‐methyl‐5‐hepten‐2‐one. Evidence that other unsaturated volatile ketones are also formed was obtained by catalytic reduction of the reaction mixture, when their more stable saturated derivatives were isolated. These ketones may arise by fragmentation of an α‐farnesene derivative at the central tertiary carbon atom in each of thre

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230508

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractLittle difference was observed in the extent or rate of hydrolysis when either rumen hemicellulase orTrichoderma viridecellulase + hemicellulase were incubated with cell‐wall preparations from oven‐dried and freeze‐dried samples of ryegrass, cocksfoot or white clover, respectively. Results of rumen nylon bag experiments were essentially similar to those from thein vitroenzyme digests. Although oven drying denatured about one‐third of the protein, rendering it insoluble in hot neutral detergent, this protein did not interfere with the enzymic hydrolysis of the cell‐wall polysa

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230509

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractRegularly shaped samples of flesh from a lean fish from temperate waters, cod (Gadus morrhua,) and a fatty fish from tropical waters, hilsa (Hilsailisha), were dried to various extents in a mechanical drier at 30 °C. Similar blocks of muscle were subjected to the same temperature conditions but wrapped to prevent dehydration in order to compare the effect of heating without dehydration. The changes in extractable proteins, non‐protein nitrogen, bacterial count, pH and, in the case of hilsa, lipid oxidation are reported. The amount of extractable myofibrillar protein decreases markedly during both heating and drying, the rate being faster for cod than for hilsa and the extra effect of drying over heating alone is different in the two species. The bacterial count increases continuously with time in the case of the heated samples but reaches a steady value and then decreases during drying. Non‐protein nitrogen and pH changes are similar to the bacterial changes. There is marked lipid oxidation during both heating and drying, the effect being greater in the dried samples. It is concluded that most of the protein changes during drying are due to the effects of heating rather than dehydra

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230510

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractAn experiment is described in which feather and offal meal was used at levels of 0, 2.6, 5.2 and 7.8 and 10.4% to replace soyabean meal and at a level of 14.0% to replace both soyabean meal and meal and bone meal in a non‐fish meal containing control diet fed to light hybrid caged layers.Replacement of the soyabean meal by feather and offal meal did not adversely affect total or mean egg weight up to the 7.8% level of addition. The efficiency of utilisation of metabolisable energy (ME) for egg production was adversely affected at the higher levels of addition.The addition of 0.07% DL‐methionine to the control diet resulted in a statistically significant improvement in percentage production, total egg weight and efficiency of ME utilisation.Mould growth occurred in stored feather and offal meal when the dry matter content was below about 90%.The proximate, Ca, P and amino‐acid analyses of the feather and offal meal are pres

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230511

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY