Environmental effects on cv Cabernet Sauvignon (Vitis vinifera L.) grown in Hawke's Bay, New Zealand.: 2. Development of a site index

Based on observations of Cabernet Sauvignon phenology, cropping and fruit characteristics at six vineyard sites in Hawke's Bay (New Zealand) studied over three seasons, a numerical model is proposed to characterise environmental conditions of a vineyard site. The proposed model is based on air temperature in October and January, seasonal rainfall, rooting depth, gravel percentage and clay-to-silt ratio in topsoil. The 'Site Index' (SI) calculated from these variables was significantly correlated with soil temperature and volumetric soil moisture content, themselves closely linked with clay-to-silt ratio, air temperature and rainfall. Vegetative growth, canopy characteristics, precocity of veraison, total anthocyanins, TSS and malic acid concentration in grapes, as well as wine sensory score, were all significantly correlated with the SI values at six sites and over two seasons. Over the same period, correlation of SI with several viticultural variables was generally stronger than five existing climatic indices for viticulture calculated for these sites. The proposed SI index appears to have potential use for vineyard zoning and site selection and evaluation.     

Dependence of wine sensory attributes on vine water status

The dependence of wine sensory attributes on the water status of the source vines was determined following vineyard irrigation treatments which included early and late season water deficits and continually irrigated vines. In both seasons, the experimental wines made from the different irrigation treatments did not differ in the concentration of residual sugar or ethanol, titratable acidity, or pH. The concentrations of anthocyanins and total soluble phenolics in the wines were greater from water deficit treatments than from continually irrigated vines. For sensory evaluation, a novel protocol for paired comparisons was developed to test separately for differences in wine appearance, flavour, taste and aroma; differences were detected for each wine comparison. In both seasons, continually irrigated wine differed from early and late season water deficit wine, and early season water deficit wine differed from late season water deficit wine in appearance, flavour, taste and aroma. The sensory differences were not attributable to differences in vine yield or fruit maturity. When professional wine tasters were sampled using similar tests, a majority was able to detect visual but not flavour differences between a selected pair of wines. It is concluded that, where vine water status can be altered, irrigation offers a means to manipulate wine sensory characteristics in the vineyard.     

Variation in vine vigour,grape yield and vineyard soils and topography as indicators of variation in the chemical composition of grapes,wine and wine sensory attributes

Background and Aims: Vineyard variability makes satisfaction of winemaker demands for uniform parcels of fruit that are suitable for particular product streams difficult. Indeed, it may not be possible to satisfy these demands without being able to adequately characterise differences between wines derived from different fruit parcels or different areas of the same vineyard, understanding how final wines are affected by management decisions implemented in the vineyard, and/or understanding the effects of variation in the vineyard's biophysical characteristics (e.g. soil, topography) on grape and wine composition. This work sought to identify and examine relationships between the chemical and sensory attributes of wines derived from different parts of the same block and the biophysical characteristics of these different vineyard areas. Methods and Results: Remote sensing of vine vigour, yield mapping and EM38 soil survey were used to identify zones of contrasting vineyard performance in a Cabernet Sauvignon vineyard in the Murray Valley region. Small‐lot wines were made from fruit sourced from these zones. Both sensory and chemical analysis (solid phase microextraction‐gas chromatography‐mass spectrometry) of these wines demonstrated them to be different. Likewise, soil properties and indices of vine nutrition differed between the zones. Conclusions: This work suggests that it is possible for robust relationships to be established between specific (manageable) biophysical attributes of the place where grapes are grown and the sensory and chemical characteristics of the wines derived from them. It also supports the view that terroir is spatially variable at the within‐vineyard scale. Significance of the Study: The work provides a foundation for further research aimed at establishing how specific sensory and/or chemical properties in wines might be modified through targeted management interventions in the vineyard.     

Effect of vine age on vine performance of Shiraz in the Barossa Valley,Australia

Background and Aims

Old vineyards are often suggested to be superior to younger ones, a claim that has scarcely been investigated scientifically. The aim of this study was to investigate if vineyard age influences vine performance.

Methods and Results

Five commercial Shiraz vineyards in the Barossa Valley, SA, were selected; each site contained younger vines, which had been vegetatively propagated from older vines on the same site. Measurements of vegetative growth and reproductive development were obtained over three seasons. Results show that the effect of vine age is difficult to measure and separate from seasonal and site interactions. Vine age was strongly correlated with trunk circumference. Vines aged 49 years showed more similarities with older vines (93–168 years old) than with younger vines (6–28 years old).

Conclusions

Vine age had an impact on grapevine reproductive performance. Older vines produced a yield greater than that of younger vines. Greater vine size, measured by increase in trunk circumference over time, may be a key determining factor in increased reproductive capacity.

Significance of the Study

Vine age is commonly attributed to superior vine performance, as a precursor to fruit and wine quality. Our findings suggest that increasing vine age had a positive effect on reproductive performance in terms of yield, contrary to popular belief. This establishes a starting point for future studies that are underway to quantify if these findings have an effect on fruit and wine composition and sensory attributes.     

Growth and dry matter partitioning of Pinot Noir (Vitis vinifera L.) in relation to leaf area and crop load

Treatments varying source:sink ratio (leaf number per vine in relation to crop load) on container-grown Pinot Noir grapevines produced differences in vine growth and dry matter accumulation and partitioning. Vines with (+) and those without (-) fruit were subject to a range of leaf removal treatments. All treatments retained leaves at nodes 1–4 from the shoot base and then had: 100% (control); 66%; 33%; or 0% leaves retained from node 5 to the apex of the shoot. Leaf removal was done as leaves appeared. Leaf removal reduced vine weight. The presence of crop and the number of leaves influenced nodes per shoot and dry weight of the shoots. Removal of leaves did not influence shoot length although un cropped vines were larger in all of the above categories. Removal of either leaves or crop had an impact on leaf number, area per vine, area per leaf and leaf dry weight.'crop' vines carried fewer, and smaller leaves then the 'crop' vines. Carbon partitioning between above ground vegetative organs and roots followed the same relationship, regardless of harvest date, crop status or defoliation treatment. The 'crop 33% leaf retained' vines compensated for leaf removal by increasing their leaf size and dry weight over the '66% leaf retained' and the control.     

不同种植区烤烟烟叶类胡萝卜素与外观质量指标分值的关系

为揭示我国不同生态区烤烟外观质量差异的可能原因,研究了西南烟草种植区、东南烟草种植区和黄淮烟草种植区烤烟类胡萝卜素的含量和构成特点及其与颜色、成熟度等外观质量指标分值的关系。结果表明:西南和黄淮烟区烤烟的类胡萝卜素含量显著或极显著高于东南烟区,东南烟区烤烟的叶黄素比例极显著高于西南烟区。东南烟区烤烟类胡萝卜素总量低、叶黄素比例高的特点可能与其独特的颜色特征（桔黄偏深色域）有关。西南烟区烤烟类胡萝卜素与外观指标分值呈明显正相关性,显著或极显著的指标包括成熟度、叶片结构和色度等;黄淮烟区与西南烟区类似,但仅颜色分值与β-胡萝卜素和类胡萝卜素显著或极显著正相关;东南烟区烤烟类胡萝卜素与颜色和成熟度分值呈显著负相关关系。聚类分析结果也显示东南烟区烤烟类胡萝卜素含量与外观指标分值的关系与西南和黄淮烟区明显不同。      

藤茶感官特征定量描述分析与风味轮构建

采用感官定量描述分析法研究藤茶的感官风味特征,并绘制藤茶风味轮。研究结果表明,经培训的评茶小组确定了藤茶的5个外形描述词、5个汤色描述词、7个香气描述词、10个滋味描述词及其定义,之后通过方差分析(P<0.05)结合主成分分析(贡献率>80%),确定所列的27个藤茶感官描述词均可较好评价藤茶样品的感官品质,结合聚类分析进一步得出胶质感、鲜黄、草香、木香、槟榔香、花香、甘甜、回甘、清爽、刺喉感、粗钝感及生津是区分藤茶品质的主要感官特征属性,同时绘制出直观反映藤茶感官特征的风味轮。该研究为了解藤茶的风味品质及开发应用提供参考。     

Influence of retained cane number and pruning time on grapevine yield components,fruit composition and vine phenology of Sauvignon Blanc vines

Background and Aims: Traditionally, the start of cane pruning is delayed until after leaf fall, when carbohydrate accumulation and cane maturity are complete. However, by starting immediately after harvest, the period for pruning may be increased by at least 4 weeks, reducing peak labour demands. Trials were conducted to investigate the consequences of various pruning times on vine phenology and yield. Methods and Results: Vines were pruned using 2‐ or 4‐canes at one of four times during the winter from shortly after harvest to just before bud break in the spring. Pruning shortly after harvest caused no significant adverse effects on vine phenology or productivity. Pruning just before bud break delayed vine development. Stored total carbohydrate concentrations in the trunk were unaffected by pruning time or cane number retained after pruning. Conclusions: Carbohydrates accumulated in the trunks of grapevines to adequate levels by harvest and any post‐harvest photosynthesis and/or cane maturation that may be occurring at this time had little effect on subsequent vine growth and development. Pruning shortly before bud break delayed bud break and may be an advantage where vines are at risk to spring frosts. Significance of Study: In cool climates where leaves senesce shortly after harvest, pruning immediately after harvest will have no adverse effects on subsequent vine phenology or yield, but will extend the period available to prune the vines, reducing the peak labour demand in the vineyard. Pruning late, slightly delays bud break potentially providing greater tolerance to late spring frosts.     

Vineyard variability in Marlborough,New Zealand: characterising variation in vineyard performance and options for the implementation of Precision Viticulture

Background and Aims: Vineyards are variable. However, to date, no spatial analysis of vineyard variability has been conducted in New Zealand. We were interested to quantify variability in a Marlborough vineyard and to produce a spatial platform onto which modelled information on phenology and juice composition could be integrated. Methods and Results: A combination of remote and proximal sensing of vine vigour, direct measurement of trunk circumference, yield mapping and high resolution electromagnetic induction (EM38) soil survey was used to examine vineyard variability in a 5.9 ha Marlborough vineyard planted to Vitis vinifera L. cv. Sauvignon Blanc. Yield variation was little more than twofold, in spite of substantial variation in vine vigour which was associated with variation in the land (soil, topography) underlying the vineyard. Conclusions: A focus on tools that facilitate enumeration of variation in vine vigour may offer the greatest value to Marlborough practitioners interested in adopting Precision Viticulture approaches to grapegrowing and winemaking. EM38 soil survey appeared to be useful for describing vineyard soil variation, but because the soils that predominate over the alluvial Wairau Plains in Marlborough are shallow and stony, very low values of apparent electrical conductivity (ECa) over a narrow range were observed. However, ECa was closely correlated with trunk circumference, an index of vine vigour. In contrast to Australian studies, neither ECa, plant cell density (derived from remotely sensed imagery) nor trunk circumference were good predictors of grapevine yield. It is hypothesised that this is largely a reflection of differences in vine training systems (hand cane pruning in Marlborough vs mechanical pruning in Australia) and the greater degree of selection of buds when vines are hand pruned. Significance of the Study: This is the first such study conducted in New Zealand and provides results that contrast with similar studies conducted in Australia. Nevertheless, the maps produced are expected to provide a valuable platform for a follow‐up study aimed at understanding spatial variation in vine phenology and juice composition. The study also highlighted the power of kriging as a means of interpolating useful vineyard maps from relatively sparse, unevenly distributed sampling data.     

Effect of free and encapsulated recombinant aminopeptidase on proteolytic indices and sensory characteristics of Cheddar cheese

The recombinant aminopeptidase of Lactobacillus rhamnosus S93 in free or encapsulated form was used in production of Cheddar cheese. The effects of these enzymes on the proteolytic indices as well as sensory characteristics have been investigated during Cheddar cheese ripening. An extrusion method was used to encapsulate the enzyme in alginate beads coated with chitosan. The free or encapsulated aminopeptidase were added at the renneting or salting stage at three different concentrations (50, 500, 2000 units per 18 L of milk). Indices of secondary proteolysis were enhanced by increasing the enzyme concentration. Cheeses with the highest concentration of the encapsulated enzyme had significantly higher concentrations of soluble nitrogen in phosphotungstic acid and total free amino acids and received the highest mean scores for the sensory characteristics.     

炖制鸡肉感官评价与仪器分析指标的相关性

为构建鸡肉在传统中餐烹饪方式下的品质评价体系,对8 种炖煮鸡肉进行感官评价,同时用多种仪器对相关参数进行测定,探讨炖制鸡肉感官评分与仪器分析指标间的相关性。结果表明：8 种鸡肉样品的感官评价具有差异性,仪器分析各个参数之间也存在一定的差异性;鸡肉的咀嚼性和弹性与口感（有嚼劲）和整体感觉呈极显著正相关（P＜0.01）,可有效评价感官指标中的口感（有嚼劲）和整体感觉;肌苷酸含量与滋味（鲜香感）呈极显著正相关（P＜0.01）,可评价鸡肉的鲜香感;总脂肪含量和蒸煮损失率与多汁感呈极显著相关（P＜0.01）,可有效评价鸡肉的多汁性。     

Validating and comparing predictive models.

The bias and accuracy factors introduced by Ross [Ross, T., 1996. Indices for performance evaluation of predictive models in food microbiology. J. Appl Bacteriol. 81, 501-508] for the evaluation of the performance of models in 'predictive food microbiology' are refined by basing the calculation of those measures on the mean square differences between predictions and observations. The use of the indices is extended by presenting formulae and methods which enable evaluation of the difference between alternative models for growth of an organism of interest over a domain of environmental factors. This is done by calculating the integral mean of the square differences between the models under investigation over the domain of the environmental variables common to those models, or a sub-region of it. The use of the techniques is exemplified by evaluating the difference between four published models for the growth rate of psychrotrophic pseudomonads.     

Sensory Characterization of Sweet Corn Lines Differing in Physical and Chemical Composition.

Chemical, physical and sensory characteristics were determined in a population of 103 F₃ families derived from the cross between two sweet corn inbreds that differed in kernel properties associated with eating quality. Kernel characteristics correlated well with panel perception of sensory attributes. Chemical, physical and sensory properties were grouped into three factors: taste—including sweetness, starchiness, juiciness, and sucrose and starch concentrations; texture—crispness, tenderness, juiciness and cooked kernel tenderness; and aroma—sweet corn aroma, grassy aroma, grassy flavor and concentrations of an unknown volatile (V179). The relative importance in determining overall liking was taste 45.1, texture 30.5, and aroma 24.4%.     

烤烟主要化学成分与感官质量的相关性分析

对我国15个省及部分进口烟叶样品化学成分指标与感官质量指标间进行了简单相关分析。结果表明,所有化学成分指标均与总体感官质量呈显著或极显著的相关关系,与总体感官质量的相关程度由大到小排序依次是：总氮^-〉烟碱^-〉总糖^＋〉两糖差^＋〉有机钾^＋〉还原糖^＋〉糖碱比^＋〉无机硫^-〉钾硫比^＋〉两糖比^-〉钾氯比^＋〉氮碱比^＋〉总氯^-〉总钾^＋（指标的上标为“-”表示与总分负相关,上标为“＋”表示与总分正相关）。研究认为,相对于两糖比指标、烟叶的两糖差与感官质量的关系更为密切,相对于总钾、氯、钾氯比等指标,无机硫、有机钾与燃烧性及感官质量的关系更为密切,两糖差、无机硫、有机钾可作为烟叶品质评价的重要指标。     

Light and temperature effects on shoot fruitfulness in Vitis vinifera L. cv. Sultana: Influence of trellis type and grafting

Fruit bud initiation in Sultana is more sensitive to climatic factors than fruit bud initiation in other cultivars. This paper considers historical findings regarding the influence of light and temperature on fruit bud initiation and fruitfulness in view of modern Sultana vineyard management practices.
Past results were reviewed and confirmed by experiments in which variability in vine size and structure was introduced by grafting and modifications of trellis design. Ramsey-grafted vines were consistently less fruitful than own-rooted Sultana, possibly because of a more shaded canopy interior due to greater vegetative growth of vines grafted to Ramsey rootstock. Carbohydrate reserves of node and internode tissue in late winter between node 2 and 18 followed a similar trend along the cane as fruitfulness in the following spring.     

Climate change associated effects on grape and wine quality and production

Climate change is exerting an increasingly profound influence on vine phenology and grape composition, and ultimately affects vinifications, wine microbiology and chemistry, and sensory aspects. Among the most important climate change-related effects are advanced harvest times and temperatures, increased grape sugar concentrations that lead to high wine alcohol levels, lower acidities and modification of varietal aroma compounds. Under extremely hot temperatures, which are already being experienced in some regions, vine metabolism may be inhibited leading to reduced metabolite accumulations, which may affect wine aroma and color. Musts with high sugar concentrations cause a stress response in yeast, which leads to increased formation of fermentation co-products, such as acetic acid. If not controlled by acid addition, the higher pH can lead to significant changes in the microbial ecology of musts and wines and increase the risk of spoilage and organoleptic degradation.     

Individual differences in perceived complexity are associated with different affective responses to alcoholic cocktails

Complexity is a relevant dimension in the development of products preferences and acceptability because of its relationship with hedonic appreciation. The present study aimed to investigate the individual differences in the relationships between product complexity in alcoholic cocktails to liking and to specific sensory properties, situational appropriateness and emotional responses. Six alcoholic cocktails, all of them composed by a common bitter ingredient were selected to represent different complexity levels based on alcohol content, number of ingredients and differences in sensory properties. Products were evaluated by a consumer panel using consumer-led product specific questionnaires. At panel level, the perceived complexity was found to be aligned with the hypothesized range of complexity. When two clusters of consumers based on individual differences in complexity ratings were considered, we observed different relationships between complexity and liking as compared to panel level. Furthermore, the sensory, emotional and situational appropriateness drivers of complexity differed in the two clusters. These data showed that perceived complexity is a multi-dimensional construct in which individuals showing high familiarity with cocktails based on bitter are found to have a very high variation in complexity perception due to a difference in conceptualization of this product dimension compared to individuals with a lower familiarity.     

Quality Comparison of Hydroponic Tomatoes (Lycopersicon esculentum) Ripened On and Off Vine

There is a general belief that the quality of tomatoes ripened on vine is better than tomatoes ripened off the vine, influencing among other parameters, the price of this commodity. We compared the quality of hydroponic tomatoes ripened on and off vine by chemical, physical, and sensory evaluation to find what attributes are affected and to what extent. Lycopene, β-carotene, total and soluble solids, moisture content, ascorbic acid, acidity, pH, texture, and color were analyzed. Tomatoes ripened on vine had significantly more lycopene, β-carotene, soluble and total solids, higher a* and lower L*, and were firmer. However, a 100-judge panel rated only the color and overall liking of the vine-ripened tomatoes as more intense than the fruit ripened off vine. Therefore, the chemical and physical differences were mostly not large enough to influence the panelist's perception. The characterization of tomatoes ripened on and off vine may help to guide post-harvest handling and treatment and to improve the quality of tomatoes ripened off vine.     

Vineyard variability in Marlborough,New Zealand: characterising spatial and temporal changes in fruit composition and juice quality in the vineyard

Background and Aims: Previous work has demonstrated that vineyards are spatially variable and that this variability can be understood in terms of the underlying characteristics of the land (soils, topography) supporting the vineyard. Selectively harvesting blocks in response to such variability may be highly profitable. While it has also been shown that crop maturation is spatially variable, there may also be temporal variations in the rate of maturation. Integrating knowledge of how spatial variation in fruit composition may be moderated in time has not previously been attempted and is the key objective in this work. Methods and Results: We used a proximal sensor to map vine vigour at high spatial resolution in a 5.9‐ha Marlborough vineyard planted with Sauvignon Blanc. Vigour measurements were also related to fruit‐soluble solids (SS), titratable acidity (TA) and pH – key indices of crop maturity. Knowledge of crop phenology and maturation was used to predict how these indices changed with time. The pooled opinions of over 50 Marlborough winemakers on the optimum juice SS, pH and TA at harvest to produce a ‘typical Marlborough Sauvignon Blanc’ were used to develop a juice index (JI), which in turn was mapped in space and time at the study site. The JI showed marked spatial and temporal variation. Conclusions: In addition to being spatially variable, grape quality in vineyards also changed with time. Thus, the optimisation of decisions about harvest timing requires knowledge of spatial variability. Conversely, strategies such as selective harvesting cannot be properly optimized without knowledge of crop phenology, the maturation of fruit and their implications for fruit quality – which are all also spatially variable. In this study, we have shown that, by integrating knowledge of crop phenology with an understanding of vineyard variability and winemaker objectives through the construction of a JI, it is possible for the optimum harvest decision to be made such that fruit destined for a particular end use are harvested at the right time and from the right place. Significance of the Study: This is the first study in which knowledge of both spatial and temporal vineyard variation has been integrated. It demonstrates that in order to be optimal, strategies such as selective harvesting need to incorporate knowledge of crop phenology rather than rely on knowledge of spatial variation alone.