|
1. |
Synthetic chemicals and the food industry |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 1-7
A. C. Frazer,
Preview
|
PDF (716KB)
|
|
ISSN:0022-5142
DOI:10.1002/jsfa.2740020102
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
2. |
Spontaneous heating and ignition in stored palm kernels. II.—Reactions between palm‐kernel bag fat and gaseous oxygen |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 8-20
J. H. Burgoyne,
A. Thomas,
Preview
|
PDF (976KB)
|
|
摘要:
AbstractThe reaction of oxygen at atmospheric pressure with dispersed palm‐kernel bag fat has been studied in the range of temperature 50 to 160°c., but principally at 80°c. and with the fat dispersed on glass surfaces, although the reaction with fat‐impregnated jute has also been studied comparatively. The relationships between oxygen consumption, product formation, total pressure change and heat evolution throughout the reaction have been established and the effects of the specific surface of the fat and the pressure of the oxygen on the reaction velocity have been studied. It appears that the oxygen initially attacks the linoleate present more rapidly than the oleate (which is in greater concentration); the linoleate consequently becomes exhausted first and the reaction rate is modified. The heat of initial reaction is about 59 kg.‐cal./mole. Observations on the formation of peroxide and the disappearance of double bonds during the reaction are discussed in the light of the modern views of Hilditch, Farmer and others on the mechanism of oxidation of unsaturat
ISSN:0022-5142
DOI:10.1002/jsfa.2740020103
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
3. |
Spontaneous heating and ignition in stored palm kernels. III.—Steady‐state temperature distribution in a uniform mass of material subject to atmospheric oxidation: A uni‐dimensional treatment |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 20-30
J. H. Burgoyne,
A. Thomas,
Preview
|
PDF (752KB)
|
|
摘要:
AbstractOn the basis of previously measured rates, rate‐temperature coefficient and heat of the reaction between oxygen and palm‐kernel fat, the steady‐state temperature distribution in uniform columns of palm kernels due to atmospheric oxidation is determined theoretically using a uni‐dimensional model. Temperature rise may be controlled by three factors; (i) conduction loss, (ii) oxygen deficiency and (iii) convection loss. In practice (i) and (ii) or (i) and (iii) usually operate together; however, they may be considered separately in order to define the lengths of column, external temperatures and ventilation rates at which the column is certainly safe from spontaneous ignition; but the margin of safety cannot be determined by this simplified
ISSN:0022-5142
DOI:10.1002/jsfa.2740020104
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
4. |
The pectase activity of apples |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 30-36
A. Pollard,
Margaret E. Kieser,
Preview
|
PDF (604KB)
|
|
摘要:
AbstractA study has been made of the pectin‐demethylating enzyme system in apple tissue and the level of activity compared with that in some other fruits. The apple varieties tested show considerable differences in their pectase content. The enzyme shows a maximum activity at pH 6–6: over the pH range of the fruit the activity is much lower, but the enzyme can still produce appreciable effects. Methods for the extraction and concentration of the enzyme are described. The concentrated enzyme preparations are readily inactivated by normal pasteurizing temperatures (68–70°c.), but in juices the enzyme shows a much greater stability. The significance of these findings is discussed in relation to the production of apple juice and
ISSN:0022-5142
DOI:10.1002/jsfa.2740020105
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
5. |
The fiske‐subbarow method for determining phosphate with special reference to soil extracts |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 36-42
S. H. Yuen,
A. G. Pollard,
Preview
|
PDF (506KB)
|
|
摘要:
AbstractModifications of the Fiske‐Subbarow method are described by which susceptibility to interference by silicate, arsenate, and certain acids and salts was reduced. In view of the possibility that some soils may contain considerable amounts of extractable arsenate and ferric iron, a method for eliminating interference by these two ions, by reduction with metabisulphite, is described. By this procedure, arsenate and ferric iron up to 20 p.p.m. As2O5and 80 p.p.m. Fe had no effects on the determination.The applicability of the modified technique to the determination of phosphate in soil extracts and in plant ashes is examine
ISSN:0022-5142
DOI:10.1002/jsfa.2740020106
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
6. |
Liver meal as a riboflavin supplement for breeding hens |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page 43-46
W. O. Brown,
Preview
|
PDF (310KB)
|
|
摘要:
AbstractThe present communication draws attention to the commercial significance of an adequate supply of riboflavin in the diet of the breeding hen. The results of an experiment carried out on a commercial breeding farm are reported, in which the basal ration contained 10% of herring meal. The replacement of half the herring meal by dried liver meal is shown to increase hatchability by 16·5%, and reduce the incidence of the specific riboflavin deficiency symptom of ‘clubbed’ down in dead embryos from 5·9 to 0·8%. These results are discussed in relation to recent experiments on factors, other than riboflavin, found to be essential for hatchability. Reference is made to the riboflavin supplements used in commercial breeders' rations available in Northern Ireland at the presen
ISSN:0022-5142
DOI:10.1002/jsfa.2740020107
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
7. |
Masthead |
|
Journal of the Science of Food and Agriculture,
Volume 2,
Issue 1,
1951,
Page -
Preview
|
PDF (62KB)
|
|
ISSN:0022-5142
DOI:10.1002/jsfa.2740020101
出版商:John Wiley&Sons, Ltd
年代:1951
数据来源: WILEY
|
|