ISSN:0022-5142    

DOI:10.1002/jsfa.2740020802

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractHydrogen peroxide has been used as a reagent for studying oxidation turbidities in bottled apple juice. The extent of sediment formation is dependent upon concentration of both dissolved oxygen and of an oxygen acceptor which is probably tannin, since juices with high tannin contents throw heavier deposits than others. Prolonged storage in bulk before bottling and heat treatment by pasteurization reduce the volume of deposit in bottle. Ascorbic acid added as an antioxidant is only slightly effective in controlling oxidation turbidities. The role of dissolved oxygen in apple juice is discussed at some length.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020803

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractA description is given of the berry fruit‐growing industry in Southern Tasmania. The methods of harvesting and conditions of transportation are described. Analyses of blackcurrants and raspberries, made during the 1948, 1949 and 1950 seasons, are presented with a view to providing information of assistance in determining the amounts of these fruits in pulps and jam

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020804

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractThe concentration of total carotenoids in various sections of the root of the carrot was studied by extracting the fat‐soluble yellow pigment and estimating it colorimetrically. The concentration had a general fall longitudinally from crown to tip although there was a small increase just beyond half‐way. The side roots and the ‘rat‐tail’ root had relatively very low concentrations of carotenoids.The pigmentation of xylem was always less, and varied much more, than that of the phloem but the two were positively correlated. Carotene comprised about 70% of the total carotenoids in the xylem and this percentage was positively correlated with depth of pigmentation. The concentration of carotenols in xylems of different carrots was much more nearly constant than that of

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020805

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractFreshly harvested carrots were stored at about 6°c. in a closed tin box. Loss of weight and mould growth were negligible. From time to time tiny cylinders were removed from each carrot and total fat‐soluble pigment was extracted and estimated colorimetrically. This pigment increased during storage. The increase, which was unrelated to variety, age or initial pigmentation, reached a maximum of 11% ±3.3 in about 60 days and declined thereafter. The carotenol (‘xanthophyll’) fraction increased much more than the carotene fraction. No evidence was found for the conversion of any carotenoid pigment into a deeper one and the conclusion is reached that a colourless substance is converted into a colou

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020806

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractThis research was undertaken to determine the relative suitability of a range of Austenitic stainless steels for use in equipment for handling hot citrus fruit concentrates containing sulphur dioxide. The work was carried out as two parallel investigations in separate Laboratories using, as corroding agents, in one Laboratory a hot solution of citric acid, sugar, common salt and sulphur dioxide, and in the other, natural citrus fruit concentrates containing sulphur dioxide.It is shown that the steels which contained from 2% to 3% of molybdenum were much more resistant to both these agents than were similar steels which did not contain this element. It is reasonable to suppose that the molybdenum‐bearing steels would give satisfactory service in the citrus juice industry, and this opinion has been confirmed by further tests under factory conditions.It is noted that the use of welding in the fabrication of stainless‐steel equipment frequently causes a lowering of the corrosion‐resistance of the steel in the welded region. This applies to some extent even with the molybdenum‐bearing

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020807

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractExperiments are described in which thiouracil was given to fattening pigs under different systems of feeding. When individually fed pigs received 0.1% thiouracil in the meal ration, they increased in weight from 150 lb. to 210 lb. almost a week sooner than the controls, with a saving of about 45 lb. meal (20%). Thiouracil given to younger pigs tended to extend the period required to increase from 100 lb. live weight to 210 lb., as compared with the controls; the saving of food was up to 75 lb. per head (17%).From the results obtained it is concluded that the frequency of thiouracil administration, as distinct from the daily intake, is an important factor in determining the ultimate response. Attention is given to the effects of thiouracil on carcass quality and composition.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020808

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractAfter removal of calcium as oxalate, magnesium (50–500 μg.) is precipitated as magnesium ammonium phosphate in a centrifuge tube in the presence of citrate, which prevents the interference of iron and aluminium. The magnesium in the precipitate is determined by titration with standard hydrochloric acid using the ‘4.5’ indicator. Manganese if present interferes but may be allowed for by determining the manganese in the precipitate and applying a correction

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020809

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractAnalytical, viscometric and pH data were determined for two samples of karaya gum (Indian and West African), and the effect of dry grinding on the viscometric properties and on particle size was studied. The analytical data were in agreement with those published previously and were not affected by grinding; the pH changes on the addition of alkali indicated either the presence of free acidic groups, or of esterified acidic groups. The pH value had a marked effect on the degree of dispersion of the gums in water, and the viscosity‐pH curves showed pronounced maxima, but at different pH values for the two gums. The electro‐viscous effect became significant only at extreme dilution, and it was possible to apply the concentration‐viscosity equations of Wissler to the aqueous solutions of the gums; these showed that the effect of grinding for various periods was to produce a series analogous to a homologous series. The changes in particle size produced by grinding are pres

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020810

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740020811

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY