ISSN:0022-5142    

DOI:10.1002/jsfa.2740010102

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010103

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractThe ascorbic acid in black currants is remarkably stable. It has been found that this fruit contains substances which inhibit the oxidation of ascorbic acid by the enzyme systems of Bramley apples. Partial separation of the active substance into two main fractions has been achieved. The one is associated with the anthocyanin pigments, and the other is associated with the yellow flavanone pigments which resemble “vitaminP

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010104

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractAnalytical data are presented, which have been collected over a period of years (1925–48), for the purpose of aiding in the determination of the fruit content of fruit product

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010105

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractAnalysis of cabbages grown on the same plot at Greenford (Middlesex) from seed of both English and South African varieties revealed that, in general, the English varieties had higher concentrations of vitaminC. Results of a similar experiment, with a smaller number of plants, at two places in South Africa tended to confirm this conclusion. Agreement between the results from the two places was sufficiently good to indicate that location had little or no influence. Unusually high concentrations of dehydroascorbic acid, probably caused by some seasonal effect, were found in the cabbages grown at Greenford. English spring cabbages grown in South Africa, under the same conditions as the other varieties, showed vitaminCcontents of the same order, whereas in England, in previous seasons, it has been found that spring cabbages contain a higher concentration of vitaminCthan those harvested in summer and winter.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010106

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractA method was developed during World War II for special military needs, to delay the usual manifestations of staleness brought about by the storage of the plain type of bread used by the British Army. The active ingredient employed was a mixture of paraffin wax and bees‐wax added to wheat flour to make a fine powder, which was incorporated into the main body of the flour before making the dough. No quantitative physical measurements which might correspond to the sensations of staleness could be made, but the rate of loss of moisture per unit made with this mixture usually kept in fairly good condition for periods up to 14 day

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010107

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractThe compositions of the blubber fats of a male and female elephant seal were examined. Evidence is presented to show that acids of chain length greater than C22were absent; there was an appreciable difference in the composition of the fatty acids from the two specimens. The possibility of a dependence of the fatty acid composition on the physiological state of the animal is discussed.The use of methyl esters in preference to fatty acids in the preliminary separation by low‐temperature crystallization has the advantage of obviating the cumbersome steps of saponification, regeneration of the fatty acids and final methylation, since the esters can be prepared directly by methanolysis. The risk of accidental oxidation of the highly unsaturated portion of the fat is also minimize

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010108

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractSubstances present in concentrated orange juice that are likely to combine with SO2are surveyed, and the more important are tested in pure solutions. They are shown to be, in order of importance, glucose, unidentified aldehydes or ketones, pectin, perhaps also breakdown products of pectin,e.g. arabinose. The behaviour of these substances, in equilibrium with SO2, is compared with that of orange juice in similar circumstances.The increased combination of SO2with glucose, as the concentration of glucose increases, is paralleled by a greater combination with concentrated than with dilute juices. At all concentrations, however, there is a greater combining‐power than can be accounted for by the sugar content of the juice. From comparison withheatedglucose solutions, it is suggested that this is due to the presence of traces of aldehyde‐ and ketone‐like substances, some of which may have been present in the juice originally and survived processing; most, it is suggested, are formed by reaction between sugars and acids in the concentrated juice during the heat‐treatment. Because of the presence of these traces of strongly‐combining substances, the proportion of SO2combining is not, as in pure glucose solutions, independent of the quantity added, but is variable; this combination is almost complete with small quantities of SO2, but with large additions of SO2it decreases towards the level corresponding to the glucose content.The combining‐power of glucose and aldehydes falls if their solutions are warmed, and the same happens withheatedsugar solutions. With concentrated juices, on the other hand, complicating factors apparently interfere, and the ultimate degree of combination increases with temperature.This paper deals only with equilibrium states; consideration of kinetics will follow in a s

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010109

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractStorage of dehydrated herrings in air at 10° C., followed by peroxide‐ and iodine‐value determinations, have been used to test the effects on the oxidation of the fat of the dried fish of(a)stowage of the raw material on ice, (b) varying the temperatures of cooking and drying and (c) antioxidants, including wood smoke. Stowage of the herrings in ice before drying has an adverse effect on the stability of the dried product, probably because of the activity of biological catalysts in the fat depot of herrings. Within limits, high temperatures of cooking, drying and storage, which may adversely affect general flavour, stabilize the fat. Previous suggestions regarding the production of antioxidants in milk by the action of high temperatures of processing apply also to herrings. Antioxidants added to the herrings before drying are ineffective, but the addition to the air during drying of wood smoke, which contains some of the simple antioxygenic phenols, stabilizes the fat of the dehydrated product very considerably. The smoke‐dried product resembles a dehydrated kipper in flavour, and it may be kept freely exposed to air at 10° C. for long periods without deteri

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010110

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740010101

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY