摘要:

AbstractMany biological assays (bioassays) have been developed to detect fungal toxins (mycotoxins). Few of these assays are as sensitive to mycotoxins as chemical assays or have been shown to be able to detect a wide range of different mycotoxins. Bioassays also suffer from a number of other problems including interference by nonfungal agents and from often being slow and less reproducible than chemical assays for mycotoxins. Bioassays have given little valuable information in their use in the surveillance of food and foodstuffs. Their major value has been in the initial identification and isolation of mycotoxins.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330112

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractThe effect of derivatisation conditions on the quantitative analysis of indole glucosinolates as the desulphated trimethylsilyl derivatives using gas chromatography is examined. Structures for the trimethylsilyl derivatives of glucobrassicin and neoglucobrassicin are suggested from an analysis of their ammonia chemical ionisation mass spectra. Caution is urged in the analysis of these compounds without prior optimisation of the conditions of derivatisation.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330113

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractVolatile constituents were isolated from yams, during cooking, by concurrent steam distillation‐solvent extraction. The essence which resulted was analysed by linked gasliquid chromatography‐mass spectrometry (g.l.c.‐m.s.) employing capillary columns and by gas‐liquid chromatography coupled with sensory evaluation of the column effluent (nasal appraisal). In addition to hydrogen sulphide and a number of high‐boiling fatty acids, 29 compounds, comprising seven hydrocarbons, eight alcohols, eight aldehydes, four ketones, a furan and a disulphide, were identified for the first time in yam. A further five components were tentatively identified by g.l.c.‐m.s. and by thinlayer chromatography of derivatives. 4‐Phenylbutan‐2‐one was the major constituent of the

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330114

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractPhenolic compounds which can potentially form C‐nitroso derivatives by reaction with nitrite can act as catalysts on the formation of anN‐nitrosamine from nitrite and a secondary amine. Using a gas chromatographic technique, this effect has been measured for di‐ and trihydric phenols and for a number of naturally occurring phenolic compounds in the case ofN‐nitrosodiethylamine (NDEA) formation. The kinetics for this catalytic effect have been studied in detail with dinitrosoresorcinol and two possible mechanisms have been suggested. In addition, it has been shown that a number of naturally occurring phenols catalyse the formation of NDEA under alkaline conditions and such catalysis can lead to the artifactual formation of nitrosamines during their a

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330115

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractThe tannin content of a number of foods and diets commonly consumed in India has been determined. Most of the tannin in legumes resides in the seed‐coat. Decortication of seeds reduced tannin to a low level with a significant increase in ionisable iron. Germination of the legumes also resulted in a decrease in tannin and an increase in ionisable iron. Diets consumed in different parts of the country had tannin contents ranging from 1.5 to 2.5 g. Much of this appeared to be contributed by spices. A high level of tannin in these foods is associated with low ionisable iron. It is suggested that besides phytates, tannin may be an important factor responsible for the low absorption of iron from habitual diets in Indi

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330116

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractAspergillus flavusLink andA. parasiticusSpeare differed in sporulation and aflatoxin B1formation on 15 brown rices differing in starch properties and protein content. There was no significant correlation between the degree of spore formation by the fungi and the amount of aflatoxin they produced in the rice samples. Differences in sporulation and aflatoxin production were not correlated with the dimensions (weight and hardness) of brown rice nor with the protein content, alkali spreading value, amylose content and gel viscosity of milled rice. Aflatoxin B1was mainly concentrated in the bran layers. Histological examination revealed that the hyphae ofA. flavusentered through cracks in the periderm and penetrated the endosperm.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330117

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

摘要:

AbstractPork meat rejected by consumers because of a nauseating taint was analysed by gas chromatography and mass spectrometry (g.c.‐m.s.) and found to contain 5–20 mg kg−1of 1,4‐dichlorobenzene. Trace amounts (10–35 μg kg−1) of 1,4‐dichlorobenzene were found in wood‐shavings used as litter materials and in the feedstuffs, but were considered insufficient to be the main cause of contamination. Meat from the following batch of pigs from the same source contained only very small amounts, similar to those present in normal pork obtained elsewhere (10μg kg−1) in several samples of normal meat, and appeared to be wi

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330118

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330119

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740330101

出版商:John Wiley&Sons, Ltd    

年代:1982

数据来源: WILEY