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Alcohol-free beers (AFBs) brewed by cold-contact fermentation exhibit a flavor reminiscent of wort which affects consumer acceptability. The aims of this study were to identify the odor-active compounds in AFB and elucidate the contribution of these to the overall aroma and worty character of the beer. Using a sensomics approach, 27 odor-active aroma compounds were identified and quantitated using gas chromatography–mass spectrometry. The most odor-active compound was methional (boiled potato-like aroma), followed by 3-methylbutanal (cocoa-like), ( E )-β-damascenone (apple, jam-like), 5-ethyl-3-hydroxy-4-methyl-2(5 H )-furanone (curry, spicy-like), and phenylacetaldehyde (floral, honey-like). The important contribution of these flavor compounds to the worty and honey aroma of AFB was determined by sensory assessment of the recombinate in a beer-like matrix with omission tests. The role of 5-ethyl-3-hydroxy-4-methyl-2(5 H )-furanone in AFB aroma was reported for the first time. The outcomes from this study are of relevance for the brewing industry to design strategies for the reduction of the wortiness of AFB.

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Quantifying the exposure of agricultural workers to pesticides is difficult in the face of the heterogeneity of the pesticides used, the variability in methods of application, and the lack of adequate exposure data. This report describes an attempt to estimate long-term dermal and inhalation exposure of bulb farmers by the development of an exposure index. This proposed exposure index consists of generic levels of exposure specific to the method of application, which were derived from databases as well as from field studies. The index is further determined by farm-related parameters such as acreage and number of pesticide applications ascertained from questionnaire responses. A widely used dithiocarbamate mixture served as a marker compound for exposure to other pesticides. Ranking of 127 bulb farmers according to calculated lifetime dermal exposure correlated only moderately to ranking based on duration of exposure, e.g., years of exposure and farm acreage. This finding indicates that the proposed exposure index could provide a useful estimate of long-term exposure to a mixture of pesticides in epidemiological investigations.

Although present in concentrations in microgrammes per litre level, aldehydes, in particular those derived from Strecker degradation, are known to majorly contribute to the undesired wort flavour of alcohol-free beers. In order to improve currently available products, one needs to understand the underlying cause for the over-prevalence and identify leverage points and methods to selectively reduce the aldehydes in alcohol-free beers. This work gives a short overview on relevant flavour-active wort flavours identified in alcohol-free beer and on their involved chemical formation pathways. Consequently, aldehyde removal technologies in general and in brewing industry are presented. Adsorptive removal of off-flavours by aldehydescavenging groups is already widely exploited in the packaging industry and may achieve reduction of these components to near depletion, depending on the process conditions. Its principles are adaptable to recovering off-flavours before filling. Also, supercritical CO 2 extraction has been successfully applied to separate flavours from food matrices. In brewing, the focus has been set to biologic conversion by restricted fermentation steps, but the reduction of key components of more than 70% is not achieved. Newer developments focus on thermal separation techniques that not only include non-specific physical dealcoholisation but also more selective technologies such as pervaporation, where aldehydes are reduced to near depletion. However, for most unit operations, selectivity and capacity are not yet investigated. Future research should explore the shortcomings of current techniques and overcome bottlenecks either by developing more specific methods for aldehyde removal and/ or a clever combination of unit operations to optimise the separation and process integration.

A prospective study was performed in the Dutch flower bulb culture to investigate the possible effects of subchronic exposure to the soil fumigant 1,3-dichloropropene (DCP) on liver and kidney function and on glutathione conjugation capacity in blood. Urine spot samples and venous blood samples from 14 workers applying DCP (applicators) were taken at the start of the season in July, and after the season in October. The parameters of liver function measured were: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, y-glutamyltranspeptidase, and total bilirubin (conjugated and unconjugated). Total bilirubin was significantly decreased from 9-5 before to 7-0 pmol/l after the season. In combination with an increase in serum y-glutamyltranspeptidase activity from 12-5 to 19 5 UlI this indicates moderate hepatic enzyme induction. To study renal function, creatinine and i2-microglobulin in serum, and f,-microglobulin, albumin, alanine aminopeptidase, f-galactosidase, and retinol binding protein in urine were measured. The glomerular func-R T H van Welie tion parameters albumin in urine and creatinine in serum changed significantly during the season: albumin concentration increased from 5-2 to 7-6 mg/l, whereas creatinine excretion decreased from 93-0 to 87 5 pmol/l. The tubular function parameter retinol binding protein also increased in concentration from 20-0 to 26-9 ug/l. Therefore, a subclinical nephrotoxic effect of subchronic exposure to DCP cannot be excluded. Effects on glutathione conjugation capacity were studied by measuring erythrocyte glutathione S-transferase activity and blood glutathione concentrations. The activity of glutathione S-transferase in erythrocytes was significantly decreased from 4-7 before to 3-3 UIg haemoglobin after the season. The same was true for the blood glutathione concentrations, which decreased from 0-93 to 0-82 mM. Both parameters seem to be affected by exposure to DCP.

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