Winegrowing Futures Final report Theme 5 Matching wine composition to consumers The National Wine and Grape Industry Centre is a research centre within Charles Sturt University in alliance with the Department of Primary Industries NSW and the NSW Wine Industry Association Contents Abstract 1 Summary 1 Background 2 Aims 4 Experiments 5 Experiment 5.1 Characterisation of Hunter Valley Semillon 5 Materials and methods 5 Results and discussion 8 Experiment 5.2 Consumer preference of Hunter Valley Semillon 11 Materials and methods 11 Results and discussion 11 Experiment 5.3 Sweetness acceptance of novices, experienced consumers and winemakers in Hunter Valley Semillon wines 14 Materials and methods 14 Results and discussion 16 Experiment 5.4 Sensory characterisation of bottle age using Hunter Valley Semillon Wine 19 Materials and methods 19 Results and discussion 21 Experiment 5.5 What do consumers think about Semillon? 26 Materials and methods 26 Results and discussion 27 Experiment 5.6 Winemaking consistency 30 Materials and methods 30 Results and discussion 30 Experiment 5.7 Wine chemistry analysis of Semillon flavour compounds 30 Materials and methods 30 Results and discussion 34 Experiment 5.8 Grape and wine composition in Semillon influenced by vine resources under different environmental conditions 102 Materials and methods 102 Results and discussion 106 Experiment 5.9 Consumer wine show days and what they offer: Do the right consumers attend? 113 Material and methods 115 Results and discussion 115 Experiment 5.10 Consumer wine show days and what they offer: Coming up with a valid measure 119 NWGIC Winegrowing Futures Final Report Page i Experiment 5.11 Consumer wine show days and what they offer: Testing the method in wine shows 122 Results and discussion 123 Experiment 5.12 Vineyard management and Semillon wine styles in the Riverina 125 Material and methods 126 Results and discussion 127 Experiment 5.13 Manipulating Semillon wine aroma profile with different strains of yeasts 136 Material and methods 136 Results and discussion 137 Experiment 5.14 Vineyard and Semillon wine styles in the Hunter Valley 139 Material and methods 139 Results 141 Discussion 148 Outcomes/conclusions 149 Outputs 153 Appendices 158 Appendix 1 Communications 158 Appendix 2 Intellectual property 160 Appendix 3 References 161 Appendix 4 Staff 169 Appendix 5 Other relevant material 170 Appendix 6 Budget reconciliation 193 Page ii NWGIC Winegrowing Futures Final Report THEME 5 Matching wine composition to consumers Abstract The outcomes of theme 5 fall broadly within three categories. Firstly, the project built capacity in the consumer- sensory, experimental winemaking and chemical analysis domains at the NWGIC. Secondly, the project developed new methods within those same areas. Finally, the project identified wine styles that appeal to consumers, how they can be developed and possibly even how they could be marketed. acceptance of specific styles of this wine. The use of Summary paired comparison tests also enabled a quantitative Research in this report has shown that a substantial basis for winemakers to produce HVS with a range sensory profile can be produced for young Hunter of residual sugars appropriate to the acceptance Valley Semillon (HVS) which would be suited for of the consumer. By choosing test wines that were immediate consumption. Furthermore, one style was not typically associated with overt sweetness, the identified that possessed both early drinking appeal most likely conditions to find differences between and an apparent aging potential. Further research is ‘experts’, ‘novices’ and winemaker consumers have needed to discover the winemaking and viticultural been fulfilled. Having established differences do practices that lead to each of the four styles defined, exist between specific consumer groups for sweet as well as consumer preference research to determine preference in HSV, future research is now required whether all styles appeal to consumers. to extend this investigation to other wine styles, and In addition fresh fruit characters and acid-sugar broader consumer segments such as specific export balance were found to be important drivers of markets of importance to the wine industry. preference for HVS. To a lesser extent, developed The effect of three years bottle age on HVS has characters were important to a specialised segment of been investigated using sensory descriptive analysis. the market. An avenue for Hunter Valley Semillon to Different HVS wine styles have been shown to become even more approachable to consumers, with develop at different rates. The ability of many HVS a new focus on an early drinking style, was discussed. wines to retain their original primary fruit character It is hoped that quintessential HVS, “one of Australia’s whilst also developing desirable aged attributes has great gifts to the world of wine”, will become more also been demonstrated. popular with consumers in the long term, as they are The ranking of perceived aroma compounds introduced to the early drinking style and graduate to and the relative potency of aroma compounds as other styles. extracted from Semillon wine was investigated. Of The influence of the level of critical tasting and the compounds identified, those stemming from industry experience on sweet preference for consumer yeast-fermentation processes would appear the categories, reported here, has not been previously most common group of compounds contributing reported in the scientific literature. This investigation to the aroma of the extracts. A range of unknown demonstrated that each consumer category based compounds were found to be of high aroma potency on knowledge, experience and involvement in the and are potential targets for future identification and wine industry, preferred different levels of residual recombination experiments. sugar and sweetness in HVS. Experienced consumers Research led to an improved understanding of the preferred wines with less added glucose than did role of carbohydrate and nutrient reserves during the novice group and significant differences existed grape maturation under different environmental at high glucose additions (32.0 g L-1). Research conditions, particularly with regard to fruit and wine confirmed the necessity to control for level of composition. The understanding of different vineyard experience within a general consumer group, not just management practices on critical aroma and flavour between consumers and ‘experts’. Results suggest that compounds assists in optimizing grape production. a higher than typical residual sugar level may increase Different vineyard management practices altered consumer acceptance of HVS for novice and expert nutrient and carbohydrate reserves and ultimately consumers alike, but may also alter winemaker’s vine performance. Understanding the impact of these NWGIC Winegrowing Futures Final Report Page 1 management practices on fruit N compounds assists in on traditional market segmentation approaches to optimising grape and wine production. Post-harvest consumer preference studies. N additions generated different sensory attributes in • Validated a small scale wine making protocol for wine compared with those wines made from different white wine. N-status plants. This information suggests further benefits from optimisation of N management in the Background vineyard. A complete amino acid profile of berry and wine samples was analysed to investigate more Site-specific practices and Semillon detailed nitrogen storage and mobilisation processes wine composition at different price during berry ripening and fermentation. The analysis points of this data is currently in process. Further research in There exists some scientific evidence that supports yeast nutrient requirements is still necessary. the relationship between yield and grape and wine The effect of crop removal on Riverina Semillon was composition (Chapman et al. 2004), but other work investigated. There was only a small impact on the shows that it is not significant (Keller et al. 2005). final aroma profile of Semillon wines with 33% and, Through pruning and fruit or shoot removal we even, 50% bunch removal at pea size (EL stage 31). can manipulate vine cropping levels. These different Any differences were too small for trained panellists to crop regulation methods can have varying levels of describe and, thus, probably too small for the average accuracy in targeting desired yields, different effects wine consumer to differentiate. Thus, reducing crop on vine physiology and fruit composition, and finally load of Semillon in the Riverina below what is normal different economic consequences (some will be more seems to have little effects on wine flavour profile. expensive than others). This area has been a subject of The flavour components still need to be analysed some study (Clingeleffer 2002), however there is still a chemically in the grape and in the wine at different lot of uncertainty in the wine industry in this respect, stages of ageing to understand their synthesis and and furthermore there are few scientific publications degradation. The vineyard itself seems to be more on this topic relevant to Australia. Vine cropping important than the actual crop removal. The wine of levels will also tend to vary with site and season. vineyard C showed a relatively strong change when With the sharp drop in grape prices, there is the fruit was removed; on the other hand, no effect naturally increasing interest among grape growers could be observed