Australian Wine Research Articles

Methoxypyrazines in Sauvignon blanc Grapes and Wines

Three methoxypyrazines were identified and quantified by gas chromatography/mass spectrometry in wine and juice samples of <i>Vitis vinifera</i> L. cv. Sauvignon blanc. Twenty-two wines of Australian, New Zealand, and French origin were analyzed together with 16 juice samples from four Australian regions. 2-Methoxy-3-(2-methylpropyl)pyrazine was present in all wines (0.6 - 38.1 ng/L) and all juice samples (0.6 - 78.5 ng/L); it was invariably the major methoxypyrazine. 2-Methoxy-3-(1-methylethyl)pyrazine was found in 11 wines (0.9 - 5.6 ng/L) and almost all juice samples (0.2 - 6.8 ng/L). In three wines and some juice samples, small quantities of 2-methoxy-3-(1-methylpropyl)pyrazine were found (typically 0.1 - 1.0 ng/L). Methoxypyrazine levels in the New Zealand wines were significantly higher than in the Australian wines (<i>p</i> &lt; 0.001). Fruit grown under cool conditions gave higher grape methoxypyrazine levels than fruit grown under hot conditions. Grape methoxypyrazine levels were relatively high at veraison but decreased markedly with ripening.

Determination of free sulphur dioxide in red wine by alternating current voltammetry

Anthocyanins and oxygen interfere in the determination of ‘free SO2’ in red wine by d.c. and differential-pulse voltammetry. However, the a.c. voltammetric behaviour of anthocyanins extracted from red wine shows that there is no interference in the determination of SO2. Furthermore, there is minimal interference from oxygen which overcomes the need for de-oxygenation and its associated loss of SO2. A phase-selective second harmonic a.c. voltammetric procedure is described for the determination of free SO2 in red wine. The results of the analyses of several red wine samples are compared with those given by the spectrophotometric method accepted by the Australian wine industry.

Erratum

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/EUM0000000001541. When citing the article, please cite: Lester W. Johnson, Liane Ringham, Kevin Jurd, (1991), “Behavioural Segmentation in the Australian Wine Market Using Conjoint Choice Analysis”, International Marketing Review, Vol. 8 Iss: 4.

Pricing in the Australian Wine Industry

The complex issue of wine pricing is addressed with reference to the Australian wine industry. The influence of the costs of production, government policy and legislation, the image sought for the wine, competitive forces, distribution channel costs and consumer behaviour are detailed.

Erratum

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/EUM0000000000603. When citing the article, please cite: Frances Edwards, Tony Spawton, (1990), “Pricing in the Australian Wine Industry”, European Journal of Marketing, Vol. 24 Iss: 4, pp. 11 - 17.

Erratum

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/EUM0000000000587. When citing the article, please cite: J.P.A. Burns, M.J. Meyler, P. Tiernan, A.J. Fischer, (1989), “The South Australian Wine Grape Market: An Analysis Using Experimental Economics Techniques”, European Journal of Marketing, Vol. 23 Iss: 9, pp. 15 - 26.

Determination of 14C in Alcoholic Beverages

A simple and quick method for the determination of 14C in ethanol has been developed, using an ultra low-level liquid scintillation counter. I have studied factors influencing the lower limit of detection and have shown that liquor can be measured directly without pretreatment. Results of measurements on Austrian wines are presented and compared with results obtained from tritium measurements. The applicability and limitations of the results to age determination are discussed.

Genetic characterisation of New Zealand and Australian wine yeasts. Occurrence of killer systems and homothallism.

Twenty five culture wine yeast strains from New Zealand and Australia were examined for killer capability or sensitivity. Eight yeast strains were K2 + killers, six of the K2 + R1 - R3 + phenotype and two of the K2 + R1 - R3 - phenotype. The seventeen sensitive strains were separated into four phenotype classes. The homothallic life cycle was detected in twenty-one strains and one further strain is probably triploid.

Formation of Substituted Tetrahydropyridines by Species ofBrettanomycesandLactobacillusIsolated from Mousy Wines

Three species of <i>Brettanomyces</i> and two species of <i>Lactobacillus</i> capable of producing a mousy taint have been isolated and characterized from Australian wines for the first time. Growth of <i>Brettanomyces</i> yeast in a chemically defined medium, with and without lysine present, indicates that two previously identified compounds which cause a mousy taint, 2-acetyl-1,4,5,6-tetrahydropyridine and 2-acetyl-3,4,5,6-tetrahydropyridine, may be synthesized from lysine. Growth of a <i>Lactobacillus</i> in a grape juice/yeast extract medium demonstrated the formation of the two acetyltetrahydropyridines by bacteria, and also implicated ethanol in the formation of these two compounds. Substitution of ethanol with <i>n</i>-propanol resulted in the novel formation of the propionyl analogues of the two "mousy"acetyltetrahydropyridines.

Occurrence and properties of bacteriophages of Leuconostoc oenos in Australian wines.

Bacteriophages specific for Leuconostoc oenos were isolated from four red wines undergoing malolactic fermentation in one winery. Bacteriophages were not found in samples of 16 other wines. The morphology of the phages was examined by electron microscopy. The phages did not lyse all strains of L. oenos, and susceptibility correlated to some extent with the colony morphology of the strain. Phage survived in wines at pH values greater than 3.5 but was inactivated in wines of lower pH and by the addition of sulfur dioxide or bentonite. Phage did not affect the growth of a sensitive strain of L. oenos in filter-sterilized wine.

Experimental Production of Fortified Sweet Wine by Single-Stage Continuous Fermentation. II. Control Procedures forSaccharomyces Cerevisiae

Control of fermentor productivity was examined during the production of fortified sweet wine from grape juice in a one-liter continuous fermentor with a strain of <i>Saccharomyces cerevisiae. Sacch. cerevisiae</i> strain 729 was chosen for detailed study because it is widely used in the Australian wine industry. It was demonstrated that fermentor productivity could be controlled by varying dilution rate and temperature. Dilution-rate control was more suitable for small adjustments to fermentor productivity, whereas temperature control was preferred for large changes in fermentor productivity, such as might be necessary with a decrease in grape supply.

Problems in the Australian Wine Industry

Problems in the Australian Wine Industry

Glycerol in Australian Wines and Factors Influencing Its Formation

The glycerol content of a wide range of representative Australian wines ranged from 1.36 to 9.94 grams per liter. Dry red wines contained more glycerol than dry white wines, and flor sherries contained considerably less. The strain of yeast strongly influenced the amount of glycerol present in experimental wines made under controlled conditions. Significantly more glycerol was formed by fermentation at 25° than at 15°C, and yeast-temperature interactions occurred. Addition of 100 ppm sulphur dioxide increased the amount of glycerol formed, and the increase was greater at pH 3.3 than at pH 3.8. Yeast strain-pH-SO₂ interactions also occurred. The variety of grape used (<i>Vitis vinifera</i>) influenced the amount of glycerol formed under comparable conditions, and more glycerol was formed from riper grapes. The mechanism of glycerol formation in wine is discussed in the light of the results.

Growth and senescence of the grape berry*

Benzothiazole-2-oxyacetic acid (BTOA) was applied to bunches of grapes (Vitis vinifera cv. Shiraz) at different times during their development and its effect on their subsequent growth was followed by measuring changes in berry weight, reducing sugars, malate, and tartrate. It lengthened the slow growth phase of berry development and this delayed ripening. It had no effect on the course of the first or second rapid growth stages. Greatest response to a single application was obtained when BTOA was applied at the end of the first growth stage or during the first week of the lag phase. Two and three applications made at 2-weekly intervals lengthened the lag phase more than a single application. During the prolonged lag phase malate continued to increase and reached a higher maximum than in untreated grapes. No consistent effect of BTOA on the tartrate content of grapes was apparent. The response of grapes to treatment with BTOA and other auxins is discussed in relation to growth and senescence of the grape berry. * This work was initiated at the Australian Wine Research Institute, Glen Osmond, S.A. 5064, Australia.

Bacterial production of diacetyl and acetoin in wine.

AbstractWines which have undergone malo‐lactic fermentation contain significantly more diacetyl and acetoin than wines which have not. The amounts of diacetyl and acetoin formed depend on the type of bacterium present and on the composition of the wine. Leuconostoc mesenteroides is the chief organism forming these products in Australian wines while pyruvic acid and citric acid are the chief substrates from which they are formed. The presence of a few g. per litre of glucose interferes with the formation of these products in wine.The heterofermentative rods, Lact. hilgardii and Lact. brevis, which are responsible for malo‐lactic fermentation in some Australian wines, produce diacetyl and acetoin only under conditions unlikely to occur in wines. Homofermentative lactobacilli have not yet been isolated from Australian wines.

A Leuconostoc Causing Malo-Lactic Fermentation in Australian Wines

A bacterium belonging to the genus <i>Leuconostoc</i> plays a prominent part in the malo-lactic fermentation of Australian wines which have pH values below about 3.6 and this organism predominates when the fermentation occurs at pH values below about 3.4. Although none of the strains isolated formed dextran from sucrose it is claimed that they should be included in the species <i>Leuconostoc mesenteroides</i>.

The Australian Wine Industry

The Australian Wine Industry

The lead content of some australian wines

AbstractThe lead content of 55 Australian wines was determined, the values ranging from 0.04 p.p.m. to 0.86 p.p.m. with a mean of 0.23 p.p.m. The wines comprised both export and home consumption samples and represented white and red, sweet and dry, and unfortified and fortified types.The results are discussed in relation to the legal limit of one part per million of lead in wine recently introduced by the British Ministry of Food.The literature relating to the lead content of wines is reviewed.

British Food Journal Volume 26 Issue 5 1924

In a recent article published in The Times and referring in particular to the wines of Australia and South Africa, Mr. D. F. Cranston observes that the United Kingdom offers abundant opportunities to the Australian wine‐growers if they are prepared to co‐operate and pursue a courageous policy. As regards soil and climate Australia is potentially a more prolific wine‐producing country than France. Britain is the only market the Australian growers can hope to cultivate on a sufficiently large scale, and their main difficulty here is that the British people naturally tend to regard wine as the exclusive property of France, Portugal, and Spain. The Australian growers do not dispel this impression by making use of European “titles of origin” for their labels. The fact is that Australian burgundy is being sold as a substitute for the French wine, and a substitute cannot hope to supersede the article it imitates. The Australian wine may partake of the burgundy characteristics, but it is also essentially Australian, and if it were sold under a distinctive title it would soon find a public of its own, and the growers would have no difficulty in placing their agencies here. Another point worth indicating is that the public here is essentially spirit‐drinking even in its wines. Port carries all before it to‐day; yesterday it was sherry, which now takes second place in the public's favour; and Madeira would also have had its day if only it could be produced in sufficient quantities. It is useless for the Australians to clamour for the “ port label.” The trade here, backed by the Anglo‐Portuguese Treaty, is too strong. But there would be a market in England for a distinctive Australian wine of the class mentioned. The falling franc and the rising cost of the French wines also makes the market more favourably disposed to the Australian growers. The consumption of Australian wines here has shown a substantial improvement on the past three years, though the total quantity sold over the last 12 months only amounted to 52,726 gallons. Imports have been heavier lately. Last year's Australian vintage was a record.

Australian Wine Making, with some Notes on the Use of Pure Wine Yeasts

Australian Wine Making, with some Notes on the Use of Pure Wine Yeasts