ISSN:0027-769X    

DOI:10.1002/food.19760200257

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0027-769X    

DOI:10.1002/food.19760200258

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0027-769X    

DOI:10.1002/food.19760200259

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe selectivity of hexane isomers towards cottonseed pigments and colour fixed pigments was illustrated by using spectrophotometric analysis of crude, refined and bleached oils, and by refinability and bleachability criteria. Crude cottonseed oil contains besides the alkali‐refinable gossypol and gossypurpurin, several colour fixed pigments. Anhydrogossypol, gossyfulvin, anthocyanins and carotenoids seem to be responsible for the colour‐fixation of the oil. Only carotenoids are eliminated by bleaching. Selectivities of hexane isomers towards colour fixed pigments are in the following order: isohexane

ISSN:0027-769X    

DOI:10.1002/food.19760200202

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe changes in cottonseed constituents at different boll ages ranging from 5 to 60 days after flowering are reported. A gradual depletion of sugars coincided with gradual formation of oil has been found. Proteins are accumulated at a more or less even rate. Gossypol starts its appearance in 10 days old boll, and continuously increases. The iodine value of the oils shows gradual increase, while the acid value continuously decreases. Continuous decrease in total saturated fatty acids during development and maturity was observed while linoleic acid continuously increases. The total phospholipid content of the oil continuously decreases. The total saturated fatty acid contents of the phospholipids are generally higher than that of their corresponding oils.

ISSN:0027-769X    

DOI:10.1002/food.19760200203

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0027-769X    

DOI:10.1002/food.19760200204

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractOlive oil was converted into methyl esters which were autoxidized at 60 °C. The composition of oxidized products was determined by the comparison of infrared spectra and NMR spectra of the original and acetylated samples, the sample reduced with potassium iodide and the acetylated reduced sample. Oxidized products were separated by preparative thin layer chromatography on silica gel and characterized by selective detection and by infrared spectrometry of the fractions. The oxidation products consisted of hydroperoxido butyl oleate, substituted hydroperoxides, mono‐and disubstituted monomeric derivatives and a small amount of oligome

ISSN:0027-769X    

DOI:10.1002/food.19760200205

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractPhosphatidylamine isolated from egg yolk phospholipids was autoxidized at 60 °C. Oxidation products were separated by thin layer chromatography on silica gel and by column chromatography on DEAE‐cellulose. The fractions were characterized by UV and IR spectra and by chemical analysis. Polyunsaturated fatty acids were destroyed during the oxidation, the content of primary amino groups decreased and imine derivatives appear

ISSN:0027-769X    

DOI:10.1002/food.19760200206

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe thermal treatment of vegetable oils was studied by gel chromatography on packings of styrene‐divinylbenzene copolymers. Unlike oils with a lower content of polyene acids, those with a high content of polyene acids contained a larger amount of higher oligomers of fatty acids. The gel chromatography of fatty acid methyl esters from heated oils allowed the determination of the ratio of intra‐ and intermolecular bonds arising by polymerization reactions. The results of determination of the iodine value of products were correlated with the data obtained by gel chromatogra

ISSN:0027-769X    

DOI:10.1002/food.19760200207

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractA review of analytical methods for determination of dithiocarbamate residues by carbon disulphide evaluation method was made. On basis of KEPPEL method the colorimetric step was modified. For this purpose the reaction of hydrogen sulphide with p‐aminodimethylaniline in the presence of ferric and zinc ions to form methylene blue was applied. The coloured compound after a chloroform extraction was measured at 650 nm. The method gives a very high sensitivity of about 2 μg. Recoveries obtained with zineb and maneb for various crops are satisfacto

ISSN:0027-769X    

DOI:10.1002/food.19760200208

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY