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208 Technical Review February 2014 The Australian Wine A W R I Research Institute Technical Review No 208 February 2014 Registered by Australia Post PP 531629/00034 Table of contents In this issue 1 Technical notes 6 Measuring oxidative aroma compounds in wines 6 Napping – a rapid method for sensory analysis of wines 10 Current literature 15 AWRI publications 62 AWRI events calendar 67 Editor: Michael Major, Michael Major Media All enquiries: Ella Robinson; email: [email protected] Copyright: Reprints and quotations of articles published herein are permitted on condition that full credit is given to both The Australian Wine Research Institute Technical Review and the author/s, and that the date of publication and issue number are stated. Cover photograph courtesy of Michael Major ISSN 0816-0805 Cnr Hartley and Paratoo Rd PO Box 197 T +61 8 8313 6600 Published by The Australian Urrbrae Glen Osmond F +61 8 8313 6601 Wine Research Institute South Australia 5064 South Australia 5064 [email protected] ABN 83 007 558 296 Australia Australia www.awri.com.au In this issue TECHNICAL NOTES Measuring oxidative aroma compounds in wines A new suite of analyses for oxidation-related aroma compounds has been developed and applied to a set of aged wines from a closure trial. Results suggest that phenylacetaldehyde and methional are particularly important contributors to oxidative off-flavour in this set of white wines. Napping – a rapid method for sensory analysis of wines A number of alternative methods have been developed which can be used to assess a set of wines more rapidly. One such recently developed method is ‘napping’. Napping is a way of evaluating a group of samples, with individual assessors arranging them in a two-dimensional space according to how similar or different they consider samples to be from one another. CURRENT LITERATURE OENOLOGY General (page 15) I have a dream Juice and wine handling (page 15) Effect of aeration treatments prior to/during fermentation Here’s a hot idea straight out of the microwave Influence of winemaking procedure and grape variety on the colour and composition of young red wines A great tradition looking for that next cutting edge Co-fermentation of Syrah with various additions of Viognier: effect on colour and phenolics during winemaking and bottle ageing Effects of extended grape ripening with or without must and wine alcohol manipulations on Cabernet Sauvignon wine sensory characteristics Potato, a new source of vegetal protein for allergen-free fining of juice and wine White wine aroma optimisation Flash détente an explosive option for winemakers Development of a deacidification process for wine by electrodialysis utilising a bipolar membrane: Results from a laboratory scale feasibility study Microbiology (page 19) Behaviour during malolactic fermentation of three strains of Oenococcus oeni used as direct inoculation and acclimatisation cultures Impact of volatile phenols and their precursors on wine quality and control measures of Brettanomyces/Dekkera yeasts Microbial succession in spontaneously fermented grape must before, during and after stuck fermentation February 2014 Technical Review No. 208 1 Analysis and composition (page 21) Quantitative survey of 3-alkyl-2-methoxypyrazines and first confirmation of 3-ethyl-2- methoxypyrazine in South African Sauvignon Blanc wines Reactions involving iron in mediating catechol oxidation in model wine Impact of dissolved oxygen at bottling on sulfur dioxide and sensory properties of a Riesling wine Detecting the addition of sugar and water to wine Determination of isotope ratios of the main components in wine by HPLC-co-IRMS: An approach to developing authenticity markers The content and origin of Manganese in wines Effect of metal chelators on the oxidative stability of model wine A new method for protein extraction from red wines Marketing and packaging (page 24) The wine headache: consumer perceptions of sulfites and willingness to pay for non-sulfited wines Why are discounted prices presented with full prices? The role of external price information on consumers’ likelihood to purchase Why do people avoid consuming wine? Environment (page 25) Adaptions to climatic impacts on vineyard and wine cellar practices in recent vintages for Super-Tuscan and Bordeaux reds Global warming and impact on the world of viticulture Safety of GM crops: compositional analysis The viticultural system and climate change: coping with long-term trends in temperature and rainfall in Roussillon, France Sensory (page 27) The influence of the senses on the consumption and purchase of wine Effects of ethanol, tannin, and fructose concentrations on sensory properties of model red wines VITICULTURE General (page 28) Stability of ampelometric characteristics of Vitis vinifera L. cv. ‘Syrah’ and ‘Sauvignon Blanc’ leaves: impact of within-vineyard variability and pruning method/bud load Wine sector attitudes to the adoption of Precision Viticulture Wine aroma and grapevine berry ripening: how to capture the complexity Simulating three-dimensional grapevine canopies and modelling their light interception characteristics Grapegrowers refused to be crushed Comparison of sensory attributes of fresh and frozen wine grape berries using berry sensory assessment Dealcoholisation can be controlled from the vine to wine ASEV symposium explores tannin management strategies Measurement of grapevine canopy leaf area by using an ultrasonic-based method Improving Eastern industry profitability 2 Technical Review No. 208 February 2014 Physiology and biotechnology (page 32) Understanding plant hormones Get ready to regulate your ripening Impact of preharvest and postharvest treatment combinations on increase of stilbene content in grape HPLC-DAD detection of changes in phenol content of red berry skins during grape ripening Biochemically induced variations during some phenological stages in Thompson seedless grapevines grafted on different rootstocks Effect of sunlight exclusion at different phenological stages on anthocyanin accumulation in red grape clusters Postharvest dehydration of Nebbiolo grapes grown at altitude is affected by time of defoliation Berry characterisation of cv. Shiraz according to position on the rachis Low temperature exposure of root system and inflorescence affected flowering and fruit set in ‘Chardonnay’ grapevines (Vitis vinifera) Climate and soils (page 36) Does soil temperature restrict outdoor viticulture in southern Finland? Does the answer lie in the soil? Review: soil biological properties as indicators of soil quality in Australian viticulture Global climate analogues for winegrowing regions in future periods: projections of temperature and precipitation Biochar applications in a King Valley Vineyard Conservation tillage of cover crops in vineyard soils to improve carbon sequestration and diminish greenhouse gas emissions Vineyard management systems (page 39) Pellenc Optimum: A more productive and economical range (of machine harvesters) ‘Opti-grape’ A very selective harvesting and sorting system When management is all about measurement Delaying berry ripening through manipulating leaf area to fruit ratio Postveraison application of antitranspirant di-1-p-menthene to control sugar accumulation in Sangiovese grapevines Influence of mechanical postveraison leaf removal apical to the cluster zone on delay of fruit ripening in Sangiovese (Vitis vinifera L.) grapevines Late leaf removal aimed at delaying ripening in cv. Sangiovese: physiological assessment and vine performance Cluster thinning reduces the economic sustainability of Riesling production Cakebread Cellars gives new life to old vines Can catalytic water conditioners benefit vineyards? Temporal and spatial relationships of vine pruning mass in Concord grapes Pests and diseases (page 44) Simple and fast test kit for the detection of grey mould in grapes Highlights of a newly-emerging grapevine virus: grapevine red blotch-associated virus Understanding fungicide resistance in Australian vineyards Late harvest as factor affecting esca and Botryosphaeria dieback prevalence of vineyards in the Alsace region of France First detection of tomato black ring virus (TBRV) in a French vineyard An overview of the vine mealybug (Planococcus fìcus) in South African vineyards and the use of entomopathogenic nematodes as potential biocontrol agent Organic inputs for disease management in organic blocks February 2014 Technical Review No. 208 3 Gypsophila paniculata root saponins as an environmentally safe treatment against two nematodes, natural vectors of grapevine fanleaf degeneration Rising to the challenge of bird control Researchers turn technology on phylloxera threat Vitis vinifera canes, a new source of antifungal compounds against Plasmopara viticola, Erysiphe necator, and Botrytis cinerea Grapevine canes as new source of antifungal compounds It’s all in the way you spray Options to control powdery mildew Potential efficiency of grapevine leafroll disease management strategies using simulation and real spatio-temporal disease infection data Managing powdery mildew under threat of fungicide resistance Seven things you always wanted to know about fungicide resistance Vine improvement and varieties (page 50) Breeding breakthroughs just around the corner Mount Etna: The awakening of the volcano Divico, a first new grape breeding of Agroscope resistant to the main fungal diseases It all tastes Greek to me — or will soon Me llamo Graciano, señor Comparative study of the resveratrol content of twenty-one Italian red grape varieties
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