SIMULATION OF LIGNIN PYROLYSIS

Model compound pyrolysis reaction pathways and kinetics were used in simulation of both native (e.g.. milled wood) and Kraft lignin thermolyses where either only primary or also secondary reactions are important.

Predicted products fell into one of permanent gases, tight liquids, phenolics and carbonaceous residue fractions. Product yields were more dependent on lignin type than on reaction environment.

Comparison of simulation predictions with experimental pyrolyses of actual lignins, accomplished in terms of both product identities and yields, is encouraging. It is noteworthy that the simulations are strictly a priori and incorporate no actual lignin pyrolysis information.     

The influence of ascorbic acid on the composition, colour and flavour properties of a Riesling and a wooded Chardonnay wine during five years' storage

This paper presents the results from an investigation to assess the development of a Riesling and a wooded Chardonnay wine over five years. The wines were bottled either with or without added ascorbic acid and stored under controlled temperature and humidity conditions. Ascorbic acid addition to wine at bottling had little effect on wine aroma and flavour when the wines in this study had been in bottle for 6 months or less. For both wines, at bottle storage times of 3 years or more, addition of ascorbic acid at bottling resulted in wines with no difference in aroma or less oxidised and/or more fresh fruity aromas, even if all the ascorbic acid had been depleted at the time of assessment, compared to wines without addition of ascorbic acid at bottling. In terms of colour, for the Chardonnay wines, the effect of ascorbic acid addition at bottling assessed between two weeks and two years after bottling suggested that wines without addition were browner and had more overall colour intensity. For the Riesling wines, ascorbic acid addition had no significant effect on brownness and overall colour intensity although the Riesling wines with ascorbic acid were generally higher in yellow colour. The A₄₂₀ measurements, which are widely used to estimate the brown colour of wines, did not always appear to correlate with the brown scores obtained by visual assessment or colour measures by CIELAB when wines with and without ascorbic acid addition were compared together. For both wines, after three and five years storage, the concentration of the antioxidant sulfur dioxide was either little different or else slightly(statistically significantly) higher in wines to which ascorbic acid was added at bottling than those without addition.     

底装料立式多用炉的节能减排

热处理炉通过对材料或零件进行加热、保温和冷却,使材料或零件组织改善、性能提高,零件和产品安全性增加,寿命延长。热处理炉是装备制造业节材、降耗、减排的工具和手段;同时,热处理炉制造和工作时也要消耗原材料和能源,产生废物影响环境。所以从节能减排的角度出发,高质量的热处理炉在其自身制造和运行中应消耗少、污染小,对零件的强化作用大、质量好[1-2]。本文结合瑞士索罗工业炉技术,从热处理炉的节能减排,优质高效等方面,阐述底装料立式多用炉的优越性。     

Relationships between berry size,berry phenolic composition and wine quality scores for Cabernet Sauvignon (Vitis vinifera L.) from different pruning treatments and different vintages

Background and Aims: Commercial winemakers observed differences in wine sensory properties among wines produced from vines of three different pruning treatments in a single vineyard. To clarify the relationships between berries and wine quality, this study examined berry size and berry composition and the quality rating for wines produced from the pruning treatments. Methods and Results: The study was conducted over three seasons. Berries from Machine‐, Cane‐ and Spur‐pruned vines were sampled at commercial harvest for analysis of berry size and berry phenolic composition. Wines made from each treatment were assessed for quality by a panel of winemakers. Machine berries were lighter and had higher concentrations of anthocyanins, tannins and total phenolics than Cane or Spur. Machine wines had the lowest quality scores. Comparing vintages, berries from 2004 were lighter, but did not always differ in phenolic composition to other vintages, and wines from 2004 had lower quality scores than the other vintages. Vintage effects were generally stronger than pruning effects. Conclusions: In this study, high berry anthocyanins, total phenolics and tannin concentration measures were not good indicators of wine quality scores. Changes in vineyard treatments and, in particular, vintage influences, produce incremental, but potentially important, changes to berry size and composition and to wine quality. Significance of the Study: This study is unique in its focus on the commercial reality of producing wines to a specific style and quality, while bringing scientific rigour to investigating the relationships between berries and wine quality in this vineyard over a number of vintages.     

Investigation des mécanismes de liaison impliqués dans la cohésion des compacts a usage cosmétique

La présence d'un pourcentage élevé de particules lamellaires dans les compacts à usage cosmétique les rend difficiles à compacter. La cohésion des particules de poudre n'est rendue possible que par la présence d'un liant de caractère lipophile. La détermination du bilan énergétique de compression ainsi que des mesures de dureté par indentation et de résistance mécanique des compacts mettent en évidence l'importance des propriétés rhéologiques et aussi du pourcentage auquel il est employé pour l'obtention de caractéristiques mécaniques optimales. Il est montré que les compacts cosmétiques de ce type sont un exemple d'un système de poudre humide compactée, différent en celà de ceux rencontrés dans d'autres branches de l'industrie (pharmacie, metallurgie, céramique…). Enfin, ces résultats permettent de conclure qu'une amélioration significative de la formulation passe par une bonne connaissance des propriétés rhéologiques du liant.     

Detection of Enocyanin in Cranberry Juice Cocktail by Color and Pigment Profile

Addition of enocyanin to cranberry juice cocktail can be determined by a four-step color and pigment profile. Enocyanin colorant is slightly more blue, therefore, a simple measurement of color will detect samples with 12% or less cranberry juice. Cranberry juice cocktail normally contains 25% cranberry juice. Anthocyanins and flavonoids, recoverable by a CG-50 ion exchange column, are lower in samples with 12% or less cranberry juice. Anthocyanin aglycones, found in grapes and not in cranberries, can be detected by paper chromatography in Formic reagent. Replacement of 50% of cranberry juice by a solution of enocyanin and citric acid, can be detected by paper chromatography of anthocyanins in 1% HCl in water.     

An Evaluation of Simple Methods for Following Rigor Development in Fish

Measurements obtained with a simple rigorometer (muscle tension measuring device) were found to correlate well with measurements of the relative ATP/IMP content ratio (258/250 nm absorbance ratio of perchloric extracts), muscle pH, and visual measurements of stiffness in whole fish (tilapia, Areochromis aureus) during rigor development. These simple tests yielded measurements which clearly differentiated the effects of ante-mortem stress on the rate of onset of rigor mortis and associated biochemical changes in the fish muscle.     

Detection of Enterotoxigenic Escherichia coil in Foods by DNA Colony Hybridization

A DNA colony hybridization procedure was used to identify and enumerate a heat-labile toxin-producing strain of Escherichia coli (H10407) in various types of foods. Foods were seeded with H10407 cells and examined by DNA hybridization on nitrocellulose filters with ³²P- labeled heat-labile toxin gene fragments. The number of cells recovered on plate count agar and eosine methylene blue agar was compared. With nitrocellulose filters, recoveries were about 81% on plate count agar and about 76% on eosine methylene blue agar. No significant differences in recovery were observed with ten different food types.