摘要:

AbstractEarlier work reporting an inverse relationship between the disulphide group content of flour protein and the protein content of flour has been followed by measurements of the disulphide group content of the soluble protein in flour. These have been found to vary with the protein content of the flour in a way similar to that of the disulphide group contents of the total proteins, but over a smaller range. Further experimental work on changes in the titratable sulphur in flour doughs on severe mixing has led to the conclusion that these do not provide any conclusive evidence for the occurrence of mechanical scission of disulphide bonds, and attempts to demonstrate this by other means have also so far proved unsuccessful.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150501

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe infusion of linseed oil or whale oil into the rumen of pasture‐fed identical twin cows resulted in marked reductions in intake and in the concentrations of acetic and butyric acids in the rumen. Concentrations of propionic acid however remained at or above those found during the pre‐treatment periods. Added linseed oil also resulted in an increase in the concentration of ammonia in the ru

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150502

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe hydrolysis and hydrogenation of grass and clover lipids and linseed oil have been followed in fistulated twin cows. Mono‐ and di‐glycerides, in addition to fatty acids, were found in the rumen liquor after infusion of linseed oil into the rumen. The proportions of linoleic acid found in rumen liquor 6.5 h. after infusion of linseed oil were above normal, but the proportions of linolenic acid had returned to about the pre‐feeding level in this time. The free fatty acids were more saturated than the unhydrolysed triglycerides, but the proportions of unsaturated fatty acids in the partially hydrolysed glycerides were not greatly different to those of the triglyce

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150503

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractHydrogen sulphide, methyl mercaptan and dimethyl sulphide are formed when herring are cooked at 100°

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150504

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractFree histidine was isolated from herring flesh and characterised. Its distribution in the musculature of the fish was measured, and the total content compared with that in the pilchard (Clupea pilchardus). The loss of the amino‐acid which occurs during heat‐processing was studied in relation to free sugars and sugar‐containing compounds. Measurements of the glucose content of fresh Scottish East Coast herring suggested that a maximum occurs in late June, coinciding with maximum oil co

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150505

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractFats from ripening coconut at oil development stages of 3–100% showed practically no acetyl value by a new sensitive gravimetric technique. It is suggested that biosynthesis of triglycerides in ripening coconut takes place by a ‘quantum’ mechanism, the unit of esterification consisting in the conversion of one glycerol to a triglyceride mol

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150506

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractA study is made of the relationship between the accumulation of oxaloacetic acid in the tissue and the subsequent development of low‐temperature breakdown in cold‐stored apples.A short interim period of storage at higher temperature reduces both the accumulation of oxaloacetic acid and the intensity of tissue breakdown. Concomitant changes in pyruvic and α‐oxoglutaric acids are measured and from the results obtained it is suggested that low‐temperature breakdown is caused by an interference in the operation of the Krebs cycle in th

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150507

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe steam‐volatile nitrogenous fraction of laboratory silages prepared from short‐rotation ryegrass (Lolium sp.) consisted of ammonia, ethylamine and trimethylamine. The proportions of ethylamine and trimethylamine increased during ensilage, but the ammonia‐nitrogen was never less than 97.8% of the total steam‐volatile nitrogen.Increased nitrogenous fertilisation of the herbage produced silages having higher levels of steam‐volatile nitrogen.Silages prepared from immature hertage had more steam‐volatile nitrogen than those prepared from more mature materials. Fertiliser level and maturity of the herbage had little effect on the composition of the steam‐volatile nitrogenous fraction.The compositions of the steam‐volatile nitrogenous fractions of a number of field silages (perennial ryegrass‐white clover mixtures) were similar to those of the l

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150508

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractSialic acid isolated from submaxillary gland and also from casein, and synthetic sialic acid have been used as standards in the determination of sialic acid in casein by the thio‐barbituric acid method. Consistently higher results for the apparent sialic acid content of casein were obtained with the synthetic sialic acid than with the sialic acid obtained from biological materials.A study has been made of the effects of conditions of hydrolysis on the apparent concentration of sialic acid in whole casei

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150509

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractIn three experiments each involving 16 groups of 12 birds, diets having normal to low ratios of crude protein to metabolisable energy were fed, for the first 12 weeks of life, to cockerels of a Rhode Island Red X Light Sussex cross and a modern commercial fast‐growing hybrid. Dietary ratios of crude protein to metabolisable energy were lowered by adding either maize starch or animal fat to a diet which was based on cereals and was, by calculation, adequate in all known nutrients. The efficiency with which metabolisable energy was converted to tissue energy was assessed by a carcass analysis technique which also allowed a study of the effect of diet on body composition.In both strains of bird, diets in which the ratios of crude protein to metabolisable energy had been lowered considerably below that corresponding to the 20% protein and 2.9 Mcal. metabolisable energy per kg. recommended by the (U.S.A.) National Research Council, gave rise to a greater metabolisable energy intake and greater loss of this energy, mainly as heat, per unit of live body weight. Deposition of body fat was also greater than in birds fed normal diets. The relative importance of heat loss to the environment and deposition of body fat, for disposal of excess energy ingested through overeating to compensate for inadequate concentrations of amino‐acids in the diet, may be influenced by breed and the proportion of fat in the diet. No significant differences were found among diets in the percentage utilisation of dietary metabolisable energy for tissue energy production and it may be that the differences found between strains arise solely from differences in dietary energy intake. Whatever the diet, the modern fast‐growing type of bird consumed more feed and therefore energy and made about 30% greater live‐weight gain with about 40% greater tissue energy gain over 12 weeks than the Rhode Island Red X Light Suss

ISSN:0022-5142    

DOI:10.1002/jsfa.2740150510

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY