摘要:

AbstractOf the relatively few investigations that have been made of the phospholipids of fish tissues, many have yielded inexact results, for a variety of reasons.Detailed studies have now been made of the phospholipids of the flesh of cod and haddock. The component phospholipids of this tissue show a general similarity in the two species. A complex mixture of phospholipids is present, in which lecithins predominate (50–60% of the total phospholipids). There is also a group of unidentified phospholipids, temporarily named A, B and C, with A greatly predominating. Two of these lipids (A and C) may be derivatives of a bis‐phosphatidic acid. Three types of inositol phosphatide have been detected. Phosphatidyl‐ethanolamine is a minor component, there are traces of plasmalogens, sphingomyelin is doubtful, and phosphatidyl‐serine is absent.The fatty acids of the lecithins are remarkable for their high content of C20and C22polyethylenic acids and for the virtual absence of hexadecenoic acid. Part of the lecithin fraction is soluble in cold acetone, and this material is more unsaturated than the acetone‐insoluble lecithins. Phospholipid‐A contains an unusually high proportion of stearic acid, while phospholipid‐B is virtually devoid of C22acids. The fatty acids of phospholipid‐C resemble those o

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071201

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe component fatty acids of four composite milk fat samples from groups of stall‐fed beef cows in the Inverness area were determined by the ester‐fractionation procedure. The milk fat from cows fed on grass silage resembled in composition that from dairy cows at pasture, whilst the milk fats from cows fed wholly or mainly on roots were more saturated; a feature of these fats was their relatively high content of palmitic acid accompanied by a correspondingly low content of oleic acid. In all four milk fats a reciprocal relation was observed between the proportions of oleic acid and palmitic acid present, whilst the proportion of stearic acid in these fats varied directly with their content of oleic acid. The influence of diet on the composition of the milk fats is discus

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071202

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractExperiments are described which have clarified the chemistry of the D.N.P. * method1for pyrethrum and allethrin assay. The fate during the course of analysis of a number of the non‐insecticidal contaminants has been determined and the scope and limitations of the method are reviewed in the light of the new finding

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071203

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA series of more than fifty field experiments carried out in south‐east Scotland showed superphosphate to be a more efficient phosphate fertilizer than any other with which it was compared. The apparent recovery of phosphorus by crops showed highly significant correlations with exchangeable calcium (positive), easily‐soluble soil phosphorus (negative), and summer rainfall (positive). The low (apparent) recovery of applied phosphorus in dry seasons appears to be due to the increased yield on the control plots, resulting from a higher availability of soil phosphorus. This may be caused by an increase in soil temperature in dry seasons. The optimum dressing of superphosphate for swedes on phosphate‐deficient soils was approximately 4.5 cwt. per

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071204

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractAn outline is given of the standard procedures of dough testing on the Brabender, Chopin and Simon instruments and a comparison is made of the essential differences in technique, espicially in the methods of preparation and treatment of the dough. Data from each instrument on several series of flours are compared with baking behaviour. The Flours examined include samples which had been treated in various ways, e.g., with agene, oxidising improvers, etc.The effect of the presence of yeast on the dough is important especially when comparing untreated with treated flours in relation to fermentation time requirements. It was concluded that for reliable testing of bread flours of unknown treatment the technique should ensure that the dough (1) contains the amount of water to bring it to the correct consistency at the end of fermentation, (2) should include yeast, (3) should be allowed at least 3 hours rest before the final moulding and (4) should be given adequate moulding.The Simon technique meets these requirements, and the Brabender technique can be modified to include them. The Chopin apparatus, though useful in studying untreated wheat flours and also in experimental work, does not permit such modifications to be made to its mode of use.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071205

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA method is described for measuring the water absorption of flour, using a yeasted dough 3 hours after mixing, by determining the minimum mobility on remixing in the Brabender Farinograph. This enables a correction to be applied to derive the water necessary for the dough subsequently stretched on the Extensograph. A yeasted dough is given 3 hours rest before moulding and then a further 30 minutes before stretching. The advantage over the standard method is that untreated and variously treated bread flours are shown in a more correct relation to each other in close agreement with their placings in baking practice.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071206

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe value of leaf protein concentrates as supplements to cereal diets for chicks has been studied using the ‘gross protein value’ technique. Protein concentrates from different crops have been found to vary widely in nutritive value, but have in all cases been inferior to casein. Concentrates from lucerne contained a factor depressing chick growth, the effect of which was counteracted by adding cholesterol to the diets. This factor was not found in concentrates from Italian ryegrass or white clover. The addition of lysine increased the value of diets containing leaf protein concentrates, possibly because the lysine present in the latter was partly unavailable through low digestibility of the proteins or chemical combinat

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071207

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractLeaf protein concentrates were treated in various ways in an attempt to improve their nutritive value, as measured by the “gross protein value” technique with chicks. Washing with hot water improved the value of some lucerne concentrates by removing a water‐soluble toxic factor. No appreciable improvement was obtained by: (a) varying pH of precipitation of curd, (b) different methods of drying the wet curd, or (c) solvent extraction of pigments, waxes, etc. Dried whole juice and alkali‐soluble protein had low nutritive values. The leaf protein concentrates differ considerably in “gross protein value”, but all are inferior to the better animal protein c

ISSN:0022-5142    

DOI:10.1002/jsfa.2740071208

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY