The juices from 39 strawberry genotypes were analysed for anthocyanin composition and colour characteristics. No single cultivar or breeding line possessed the innate pigment characteristics thought to confer greater colour stability on strawberry juices but the anthocyanin patterns were far more complex than hitherto reported in strawberries. Thirteen different peaks were observed during high-performance liquid chromatography of the juices and tentative identifications are proposed for two previously unidentified strawberry anthocyanins. The occurrence of pelargonidin 3-rutinoside was confirmed. Colour quality measurements derived from CIELAB L*a*b* values are reported for the fresh juices.

Red wines were made during 1992 from Vitis vinifera var Roriz grapes using a high and a low level of extraction and three levels of total sulphur dioxide (0, 75 and 150 mg SO2 kg−1). From this single experiment, the effects of total SO2 and extraction on anthocyanin composition and colour were observed by HPLC, spectrophotometry and tristimulus colorimetry. High extraction produced a wine with more total pigments and total phenols than low extraction and increased the amount of organic acids extracted during fermentation. More anthocyanins were extracted with increasing SO2 levels. On maturation, all wines lost colour and increased in brownness. Wines made without SO2 browned more than the wines made with SO2. The anthocyanins normally present in wines were all rapidly lost to trace levels at 24 months. Vitisin A, a more stable and highly coloured anthocyanin than malvidin 3‐glucoside, showed a slower decrease in concentration than malvidin 3‐glucoside and contributed significantly to the wine colour during aging. At the first analysis, the wines made without SO2 had a higher percentage colour due to polymers than the wines made with SO2. Polymerisation progressed during maturation, although the initial differences were maintained. Sensory analysis after 6 and 18 months storage by expert tasters revealed differences mainly related to the colour attributes, indicating that when wines are made using modern hygienic techniques, total SO2 has a negligible effect on aroma and flavour attributes. © 1998 Society of Chemical Industry.

The illegal use of nandrolone) and its esters in livestock, for growth promotion purposes, has been widely reported in the European Union. The target residues for surveillance of abuse in bovine urine and bile samples are 17a-and 17b-19NT, although this choice of target residues is not based on in vivo radiotracer biotransformation data. In this study, four steers were administered [ 3 H 2 ]-and [ 2 H 3 ] 17b-19NT laurate (2 mg kg 21 body mass) by intramuscular injection and blood, urine, faeces and bile samples were taken for 30 d until slaughter, after which tissues were sampled for total residue analysis. Total plasma radiolabelled residues reached a maximum of 56.3 ± 15.9 pmol ml 21 at 36 h and were still appreciable (13.3 ± 1.6 pmol ml 21 ) 30 d after treatment. Throughout the study period, total residue concentrations in bile (about 2-16 nmol ml 21 ), urine and faeces (0.5-3 nmol ml 21 or g 21 ) were higher than in other tissues sampled at slaughter. At slaughter there was evidence of residue accumulation in pigmented eye tissue (33.1 ± 6.1 pmol g 21 ) and in white (13.4 ± 3.4 pmol g 21 ) and black hair (28.9 ± 8.9 pmol g 21 ). Evaluation of radio-HPLC profiles of urine and bile extracts generally indicated that 19NT and 19NT laurate residues were present in relatively small amounts among a complex mixture of metabolites. GC-MS analysis of glucuronidase-hydrolysed bile extracts indicated that the major metabolites were 5b-estrane-3a,17a-diol, 5a-estrane-3b,17a-diol, 5a-estran-3a-ol-17-one (norandrosterone) and estra-1,3,5(10)-triene-3,17a-diol (17a-estradiol).

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