摘要:

A comparison of the traditional spectrophotometric method, with prior application of a reducing Cd column, and a high performance liquid chromatography method with an anion exchanging column for the determination of nitrate in spiced Spanish sausage, was carried out.

ISSN:0265-203X    

DOI:10.1080/02652039209374054

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The preparation of four cereal reference materials (two wheat and two maize) and the certification of their 4‐deoxynivalenol (DON) contents is described. The materials were prepared and certified within the BCR programme of the Commission of the European Community as part of a broad activity to improve accuracy and agreement of measurements of importance in food and agriculture. Reference material RM 379 was prepared from naturally contaminated wheat four blended with ‘blank’ material to achieve the desired DON content. The reference material RM 378 was prepared from naturally contaminated maize identified as containing approximately the desired DON content. Details are given of the milling, blending and packaging procedure, and the checks to ensure homogeneity and stability of the materials. The reference materials RM 396 and 377 were similarly prepared from the blank wheat and maize samples respectively. The certification exercise was carried out by five laboratories (with a further two to three laboratories providing supporting data) using a variety of extraction and clean‐up procedures with either high performance liquid chromatography (HPLC) or gas chromatography (GC) as the determinative stages.

ISSN:0265-203X    

DOI:10.1080/02652039209374055

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The amounts of substances migrating from plastics into foodstuffs with high fat contents are in most cases higher than in foodstuffs with water contents. This increase in migration commonly is due to the higher solubility of the migrating organic compounds in fat compared to water. The increase in migration is not necessarily due to an increase in the substance's diffusion coefficient due to interactions between the fat and the plastic as is often assumed. Ethanol is a good simulant for fatty foods because it has little interaction with many plastics, e.g. polyolefins, migrants are readily soluble in it, and because it is easy to work with analytically. The utilizable limits of ethanol and ethanol/water mixtures as food simulants are developed from the physical background of diffusion. The use of ethanol and ethanol/water mixtures is supported by published experimental migration results.

ISSN:0265-203X    

DOI:10.1080/02652039209374056

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A method is described for the simultaneous determination of methyl carbamate (MC) and ethyl carbamate (EC) in wines that is based on: (a) extraction of the sample with dichloromethane using an extraction tube or an alumina—Celite column, (b) concentration of the extract to a small volume, and (c) determination by gas‐liquid chromatography‐thermal energy analyser (N‐mode). The method is highly sensitive (1–2 ng/ml), accurate (recoveries >80%), and precise (CV, 5–10%). Nineteen of 27 samples of wines analysed contained traces (up to 2.7 ng/ml) of MC, and most contained EC (up to 70 ng/ml). Wines treated in the laboratory with 200 ppm dimethyl pyrocarbonate (DMPC)—a cold sterilant recently approved for use in wines—indicated that such a treatment may increase the MC contents of the wines to 10 ng/ml. Additional studies suggested that formation of MC in DMPC‐treated wines is dependent on both pH and ammonia content of the wines. The identity of MC in a few selected samples was confirmed by gas‐liquid chromatography—high resolution (10 K) mass spectrometry. The natural low levels of MC found in these wines are not considered to pose a risk to human health.

ISSN:0265-203X    

DOI:10.1080/02652039209374057

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Butyl‐, cyclohexyl‐ and phenyltin compounds were extracted from enzymically‐hydrolysed wine and beer samples with 0.05% tropolone in pentane. Methyl derivatives were made by Grignard reaction for determination by gas chromatography‐atomic absorption spectrometry. Wine and beer samples contained <0.1 to 160 nl/ml of butyltins from an undetermined source of contamination. GC‐MS confirmation of butyltins also detected phenyltin, and di‐ and tricyclohexyltin compounds at levels less than the GC‐AAS based method detection limits of 0.05–0.13 ng Sn/mL.

ISSN:0265-203X    

DOI:10.1080/02652039209374058

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Utilizing elements of methodology developed previously for food colours, total free and bound non‐sulphonated aromatic amines (NSAA) were determined in commercial samples of soft drink beverages and hard candies. Bound amines in the samples were reduced using sodium dithionite, then total NSAA were extracted into chlorofom, transferred to aqueous acid solution and diazotized with sodium nitrite before coupling with 2‐naphthol‐3,6‐disulphonic acid, disodium salt (R‐salt). The coloured derivatives were analysed using reversed‐phase ion pair high‐performance liquid chromatography (HPLC) and an absorbance detector set at 512 nm. Solid phase extraction cartridges were utilized for extraction and clean‐up of the food colours present in the sample, and the concentration of each dye was determined quantitatively using HPLC and absorbance detector wavelengths of 426, 516 or 625 nm. Levels of total NSAA were compatible with those observed previously in food colours. Commercial soft drinks were found to contain (expressed in terms of total free plus bound NSAA in the beverage) 0.19–12.6 ng/ml of aniline, 0.83–8.25 ng/ml 1‐naphthylamine and 0.62–1.12 ng/ml 2‐naphthylamine. Levels of 0.66–9.15 ng/g of aniline and 2.48–10.6 ng/g 1‐naphthylamine were found in commercial samples of hard candies. Bound NSAA in hard candies appeared to survive the manufacturing process. Recoveries averaged 96.9% for tartrazine and 89.6–97.2% for the bound amines when hard candies were prepared in the laboratory.

ISSN:0265-203X    

DOI:10.1080/02652039209374059

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper reports the evaluation of five tetrahydro‐β‐carboline carboxylic acids, formed from the interaction of woodsmoke carbonyls and tryptophan, for mutagenicity in the Ames test. Three of the compounds tested have been detected recently in smoked foods at levels in theμg/kg or mg/kg range.

ISSN:0265-203X    

DOI:10.1080/02652039209374060

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Encyclopaedia of Food Science and Technology. Volumes 1–4.Edited by Y. H. Hui, (Wiley‐Interscience, New York, Chichester, Brisbane, Toronto and Singapore, 1992) Vol 1: pp. 1–658; Vol 2: pp. 659–1439; Vol 3: pp. 1440–2210; Vol 4: pp. 1441–2972. Price £385, ISBN 0–471–5041–2 (set).

ISSN:0265-203X    

DOI:10.1080/02652039209374061

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0265-203X    

DOI:10.1080/02652039209374062

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0265-203X    

DOI:10.1080/02652039209374053

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor