The consumer preference of Hunter Valley Semillon (HVS) with varying amounts of glucose was investigated. The respondents were divided into three categories; novice (consumer), experienced (consumer) and winemakers. Experienced drinkers preferred wines with less added glucose than did the novice group. Winemakers preferred a lower level of glucose addition again. This study has also defined levels of residual sugar within which winemakers can aim to produce wine in order to fulfil the desires of the consumer, allowing winemaking decisions for residual sugar levels to be quantitatively based.

A headspace-solid-phase micro-extraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method has been developed to quantify a range of volatile compounds in Hunter Valley Semillon wines. The fibre selected for the method was a 50/30 m divinylbenzene/carboxen/polydimethylsiloxane fibre, a three-phase fibre that allows extraction and desorption of a wide range of volatile compounds of different chemical functionalities and polarities. Four internal standards, methyl isobutyl ketone, n-dodecane, 4-methyl-2-pentanol and ethyl nonanoate were used to monitor the SPME fibre extraction efficiency and integrity. Fibre integrity was monitored by plotting the ratio of the peak area for each internal standard divided by the sum of the peak area for all internal standards as a function of analysis number. The advantage of using four internal standards for better quality control of the fibre integrity is described. The identity of twenty-one volatile compounds was ascertained by comparison of their chemical characteristics (retention indices, mass spectra) with reference compounds using two columns of different polarities. Quantification was achieved using calibration curves constructed for each compound with linear regression equations having correlation coefficients (R 2 ) ranging from 0.9717 to 0.9999. The method was applied to two Semillon wines (recent vintage and aged) representative of the Hunter Valley styles. As is typical of white wines, 3-methyl-1-butanol was quantified as the most concentrated volatile compound (83 and 66 mg L −1 for the 2006 and the 1996 wines, respectively). The study highlights the use of well-defined procedures to ensure integrity of quantitative data where several fibres may be required during an extended study over one or more vintages.

Predictions of grapevine yield and the management of sugar accumulation and secondary metabolite production during berry ripening may be improved by monitoring nitrogen and starch reserves in the perennial parts of the vine. The standard method for determining nitrogen concentration in plant tissue is by combustion analysis, while enzymatic hydrolysis followed by glucose quantification is commonly used for starch. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR) combined with chemometric modelling offers a rapid means for the determination of a range of analytes in powdered or ground samples. ATR-FT-IR offers significant advantages over combustion or enzymatic analysis of samples due to the simplicity of instrument operation, reproducibility and speed of data collection. In the present investigation, 1880 root and wood samples were collected from Shiraz, Semillon and Riesling vineyards in Australia and Germany. Nitrogen and starch concentrations were determined using standard analytical methods, and ATR-FT-IR spectra collected for each sample using a Bruker Alpha instrument. Samples were randomly assigned to either calibration or test data sets representing two thirds and one third of the samples respectively. Signal preprocessing included extended multiplicative scatter correction for water and carbon dioxide vapour, standard normal variate scaling with second derivative and variable selection prior to regression. Excellent predictive models for percent dry weight (DW) of nitrogen (range: 0.10-2.65% DW, median: 0.45% DW) and starch (range: 0.25-42.82% DW, median: 7.77% DW) using partial least squares (PLS) or support vector machine (SVM) analysis for linear and nonlinear regression respectively, were constructed and cross validated with low root mean square errors of prediction (RMSEP). Calibrations employing SVM-regression provided the optimum predictive models for nitrogen (R 2 = 0.98 and RMSEP = 0.07% DW) compared to PLS regression (R 2 = 0.97 and RMSEP = 0.08% DW). The best predictive models for starch was obtained using PLS regression (R 2 = 0.95 and RSMEP = 1.43% DW) compared to SVR (R 2 = 0.95; RMSEP = 1.56% DW). The RMSEP for both nitrogen and starch is below the reported seasonal flux for these analytes in Vitis vinifera. Nitrogen and starch concentrations in grapevine tissues can thus be accurately determined using ATR-FT-IR, providing a rapid method for monitoring vine reserve status under commercial grape production.

Semillon wines from the Hunter Valley region, Australia, were evaluated by sensory descriptive analysis using 15 trained judges. The panel initially identified 37 attributes, but after training, discussion and statistical analyses the list was reduced to 12 different aromas. Additionally the tastes of acidity and sweetness were practised and results obtained. Principal component analysis (PCA) of the sensory data obtained combined with mean intensity ratings enabled the wines to be divided into four groups or 'styles' . PCA revealed a two-factor solution explaining 82.5% of the total variance, where bottle age was the most important flavour dimension. Three different styles of young Semillon wine and an aged category were determined, confirming that there is a style with substantial flavour that can sold without the need to bottle age.

The production and sale of alcohol-reduced wines, and the lowering of ethanol concentration in wines with alcohol levels greater than acceptable for a specific wine style, poses a number of technical and marketing challenges. Several engineering solutions and wine production strategies that focus upon pre-or postfermentation technologies have been described and patented for production of wines with lower ethanol concentrations than would naturally arise through normal fermentation and wine production techniques. However, consumer perception and acceptance of the sensory quality of wines manufactured by techniques that utilize thermal distillation for alcohol removal is generally unfavorable. This negative perception from consumers has focused attention on nonthermal production processes and the development or selection of specific yeast strains with downregulated or modified gene expression for alcohol production. The information presented in this review will allow winemakers to assess the relative technical merits of each of the technologies described and make decisions regarding implementation of novel winemaking techniques for reducing ethanol concentration in wine.

Difficulties with induction and cultivation of L-forms, particularly those derived from Gram positive parent cells, have constrained to some degree the ability to evaluate the pathogenicity of these morphotypes. Induction of L-forms of Lactococcus garvieae was undertaken using either charcoal or inactivated horse serum media supplemented with ampicillin, benzylpenicillin or erythromycin, the drug of choice for treatment of infections in rainbow trout, Oncorhynchus mykiss, (Walbaum), and NaCl as an osmotic stabiliser. Lysozyme treated cells could be cultured in a cell wall deficient state using media consisting of charcoal, NaCl and either ampicillin or benzylpenicillin. The influence of some amino acids for induction of L-forms was assessed by disc diffusion and combined interaction. Analysis of variance of colony counts indicated that the amino acids glycine, DL-methionine, L-threonine and L-serine (P < 0.03), and the presence of charcoal were beneficial and that inactivated horse serum was detrimental to L-form development. Electron microscopy revealed that the cell wall of L-forms was missing and this cell had a greatly expanded volume compared to parent cells. Electrophoresis of whole cell proteins showed some variation of electropherotype between parent and L-form cells. L-forms expressed greater quantities of proteins with molecular mass of 36 and 66 kDa and parent cells contained greater quantities of proteins of molecular mass 29, 43 and 60 kDa. Additional proteins of molecular mass 32, 44 and 53 kDa were present in L-form extracts, and in parent cells of 34, 38, 40, 42, 85 and 123 kDa which may represent cell wall associated proteins or alterations in expression due to different growth rates. Intraperitoneal challenge of rainbow trout with L-forms failed to produce overt infection even in immune-suppressed fish, but L-forms were shown by indirect fluorescent antibody test to remain in Veterinary Microbiology 69 (1999) 287±300 (L.M. Schmidtke) 0378-1135/99/$ ± see front matter # 1999 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 8 -1 1 3 5 ( 9 9 ) 0 0 1 2 0 -0 kidney tissue. Fish were susceptible to infection when challenged with parent cells of L. garvieae. #

The consumer preference of Hunter Valley Semillon (HVS) with varying amounts of glucose was investigated. The respondents were divided into three categories; novice (consumer), experienced (consumer) and winemakers. Experienced drinkers preferred wines with less added glucose than did the novice group. Winemakers preferred a lower level of glucose addition again. This study has also defined levels of residual sugar within

1994. Isolates of the salmonid pathogen Vagococcus salmoninarum were recovered from Atlantic salmon, rainbow trout and brown trout with peritonitis. T h e phenotypes of these isolates and the type strain of Vaz. salmoninarum NCFB 2777 were determined by morphological, biochemical and physiological tests and whole cell protein profiles by SDS-PAGE. There was a high level of phenetic similarity between the salmonid isolates and the type strain. T h e species forms short Gram-positive rods, hydrolyses L-pyrrolidonyl-/)-naphthylamide, is a-haemolytic on sheep's blood agar, grows at pH 9-6 and 10°C but not at 40°C or in 6.5% NaCl and is catalase-negative; a Lancefield group N antigen is not present. Vagococcus salmoninarum can be distinguished phenetically from similar fish pathogens including Carnobacterium piscicola, Enterococcus seriolicida and Lactococcus piscium.

Difficulties with induction and cultivation of L-forms, particularly those derived from Gram positive parent cells, have constrained to some degree the ability to evaluate the pathogenicity of these morphotypes. Induction of L-forms of Lactococcus garvieae was undertaken using either charcoal or inactivated horse serum media supplemented with ampicillin, benzylpenicillin or erythromycin, the drug of choice for treatment of infections in rainbow trout, Oncorhynchus mykiss, (Walbaum), and NaCl as an osmotic stabiliser. Lysozyme treated cells could be cultured in a cell wall deficient state using media consisting of charcoal, NaCl and either ampicillin or benzylpenicillin. The influence of some amino acids for induction of L-forms was assessed by disc diffusion and combined interaction. Analysis of variance of colony counts indicated that the amino acids glycine, DL-methionine, L-threonine and L-serine (P < 0.03), and the presence of charcoal were beneficial and that inactivated horse serum was detrimental to L-form development. Electron microscopy revealed that the cell wall of L-forms was missing and this cell had a greatly expanded volume compared to parent cells. Electrophoresis of whole cell proteins showed some variation of electropherotype between parent and L-form cells. L-forms expressed greater quantities of proteins with molecular mass of 36 and 66 kDa and parent cells contained greater quantities of proteins of molecular mass 29, 43 and 60 kDa. Additional proteins of molecular mass 32, 44 and 53 kDa were present in L-form extracts, and in parent cells of 34, 38, 40, 42, 85 and 123 kDa which may represent cell wall associated proteins or alterations in expression due to different growth rates. Intraperitoneal challenge of rainbow trout with L-forms failed to produce overt infection even in immune-suppressed fish, but L-forms were shown by indirect fluorescent antibody test to remain in Veterinary Microbiology 69 (1999) 287±300 (L.M. Schmidtke) 0378-1135/99/$ ± see front matter # 1999 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 8 -1 1 3 5 ( 9 9 ) 0 0 1 2 0 -0 kidney tissue. Fish were susceptible to infection when challenged with parent cells of L. garvieae. #

Background and Aims: Springtime root-zone warming activates mobilisation of the root carbohydrate reserves, a critical source of carbon for early canopy and reproductive development in grapevines following winter dormancy. Seasonal variability in soil temperature during spring may result in inconsistent vegetative growth and fruitset with consequences for berry growth and ripening. Methods and Results: We monitored flowering and berry ripening in Shiraz grapevines (Vitis vinifera L.) grown in large temperature-controlled pots. The vines were exposed to a cool, ambient and warm root-zone temperature from budburst to fruitset. Root starch mobilisation after budburst was linearly correlated to the cumulative heat units received by the soil. A warm root-zone temperature also hastened leaf expansion, net positive carbon assimilation, onset of flowering and fruit set, berry enlargement and the onset of veraison. At harvest, berry pH and nitrogen concentration as well as fresh and dry mass were higher for the vines exposed to a warm root-zone while berry acidity was lower. Conclusions: Warm soil temperature in spring stimulated the mobilisation of carbohydrates in the roots and accelerated shoot and reproductive development, resulting in larger berries with lower acidity. Significance of the Study: Because root-zone temperature is an environmental driver of berry size and composition, models predicting yield and berry composition can be fine-tuned to incorporate this critical parameter.

Semillon wines from the Hunter Valley region, Australia, were evaluated by sensory descriptive analysis using 15 trained judges. The panel initially identified 37 attributes, but after training, discussion and statistical analyses the list was reduced to 12 different aromas. Additionally the tastes of acidity and sweetness were practised and results obtained. Principal component analysis (PCA) of the sensory data obtained combined with mean intensity ratings enabled the wines to be divided into four groups or 'styles' . PCA revealed a two-factor solution explaining 82.5% of the total variance, where bottle age was the most important flavour dimension. Three different styles of young Semillon wine and an aged category were determined, confirming that there is a style with substantial flavour that can sold without the need to bottle age.