Wine Production : Vine to Bottle - Vinum Vine

More documents

Recommendations

Info

17 2.4 The concept of degree days A system of climatic classification based on degree days was devised by the Viticultural School of the University of California at Davis as a result of their research in matching vines to climate. A calculation is based on the seven months’ annual growing season according to the hemisphere: • Northern hemisphere: theoretical growing season = 1st April to 31st October • Southern hemisphere: theoretical growing season = 1st November to 30th April. CHAPTER 2 The vine does not grow at temperatures below 10 °C (50 °F). Each day in the growing season that the mean temperature is above 10°C is counted and totalled. Each one degree of mean temperature above 10 °C represents one degree day, e.g.: • 1st May: mean temperature 14 °C, therefore 1st May = 4 degree days • 31st July: mean temperature 24 °C, therefore 31st July = 14 degree days. Degree days are measured in either Fahrenheit or Celsius, but it is important when comparing different regions to compare like with like, i.e. °C with °C, °F with °F. The total number of degree days is then calculated. For example, in the USA the coolest climatic region (Region 1) totals less than 2500 degree days (F), whilst the hottest (Region 5) has more than 4000. Based on this classification, suitable varieties are selected to match a region’s climate. Some viticulturalists challenge the concept of degree days as an appropriate measure of mesoclimates. 2.5 Impact of climate Let us compare a Riesling wine from a cool climate such as Mosel–Saar–Ruwer, with an alcohol content somewhere between 7.5% and 10% ABV, and a Riesling from Clare Valley, South Australia,
18 Table 2.1 Comparison of annual sunshine and temperatures WINE PRODUCTION Duration of sunshine (hours) Average annual temperature °C °F Germany (average in 1400 10 50 wine regions) Bordeaux 2000 12.5 54.5 Châteauneuf-du-Pape 2800 14 57.2 with at least 12% alcohol. Generally speaking, as sugar levels increase during the ripening process, acidity levels fall. Consequently the German Riesling is likely to have higher acidity than the Australian wine, although it should be noted that the Australian producer is permitted to add acid during the winemaking process if it is thought desirable. Unless a derogation is given by the European Union, as happened in the exceptionally hot year of 2003, acidification is not permitted in the cooler regions of Europe. Black grapes need more sunshine and heat than white grapes, to ensure the physiological ripeness of the tannins in their skins. It follows, therefore, that a higher proportion of white grapes are grown in cooler regions; for example, Germany, Alsace, Loire Valley and England. A comparison of the sunshine hours and temperatures of the production regions of three very different styles of wine is shown in Table 2.1. Climate can be both friend and enemy to the vine. Vines perform at their best where there is a dormant period of about 5 months and a growing and fruit-ripening period of about 7 months. Essentially, sufficient warmth and moisture are required to be able to grow, produce and ripen grapes. It is, however, important that these conditions come at the right time in the vine’s annual growth cycle. 2.6 Weather Whereas climate is determined by geographical location and measured in long-term averages, weather is the result of day-to-day variation of those averages. The weather is the great variable in the vine’s
Page 1 and 2: FOOD INDUSTRY BRIEFING SERIES Wine
Page 3 and 4: © K. Grainger & H. Tattersall 2005
Page 5 and 6: INE PRODUCTION ivW 2.2.3 Strong win
Page 7 and 8: INE PRODUCTION viW 10.2 Must prepar
Page 9 and 10: viii WINE PRODUCTION 15.3.8 Rémuag
Page 11 and 12: INE PRODUCTION xW the bottle or in
Page 13 and 14: Preface There are, of course, many
Page 15 and 16: Acknowledgements We are grateful to
Page 17 and 18: xvi WINE PRODUCTION few years, glob
Page 19 and 20: This page intentionally left blank
Page 21 and 22: INE PRODUCTION 2W 1.1.1 Stalks Stal
Page 23 and 24: INE PRODUCTION 4W found in plants o
Page 25 and 26: INE PRODUCTION 6W Box 1.1 Definitio
Page 27 and 28: INE PRODUCTION 8W Fig. 1.3 Phylloxe
Page 29 and 30: 10 WINE PRODUCTION resistant to sho
Page 31 and 32: Climate Climate and weather have a
Page 33 and 34: 14 WINE PRODUCTION 2.2 Climatic ene
Page 35: 16 WINE PRODUCTION releasing the he
Page 39 and 40: Soil Soil is a critical factor in t
Page 41 and 42: 22 WINE PRODUCTION The most importa
Page 43 and 44: The Vineyard Viewpoints on viticult
Page 45 and 46: 26 WINE PRODUCTION In other parts o
Page 47 and 48: 28 WINE PRODUCTION Fig. 4.2 Vines p
Page 49 and 50: 30 WINE PRODUCTION Fig. 4.4 Vines t
Page 51 and 52: 32 WINE PRODUCTION 4.6 The growing
Page 53 and 54: Pests and Diseases As with any othe
Page 55 and 56: 36 WINE PRODUCTION soon as the grap
Page 57 and 58: 38 WINE PRODUCTION • Pierce’s d
Page 59 and 60: 40 WINE PRODUCTION jet machine, or
Page 61 and 62: 42 WINE PRODUCTION the vine pests
Page 63 and 64: The Harvest This is a critical poin
Page 65 and 66: 46 WINE PRODUCTION enable the grape
Page 67 and 68: Vinification - The Basics The proce
Page 69 and 70: 50 WINE PRODUCTION Fig. 8.1 Winery
Page 71 and 72: 52 WINE PRODUCTION Fig. 8.2 Winery
Page 73 and 74: Red Wine Making This chapter descri
Page 75 and 76: 56 WINE PRODUCTION is divided into
Page 77 and 78: 58 WINE PRODUCTION fermentation tak
Page 79 and 80: 60 WINE PRODUCTION 9.7 Malolactic f
Page 81 and 82: Dry White Wine Making Although the
Page 83 and 84: 64 WINE PRODUCTION for example, in
Page 85 and 86: 66 WINE PRODUCTION 11.2 Filtration
Page 87 and 88:
68 WINE PRODUCTION Fig. 11.2 Winery
Page 89 and 90:
70 WINE PRODUCTION 11.3 Stabilisati
Page 91 and 92:
72 WINE PRODUCTION important qualit
Page 93 and 94:
74 WINE PRODUCTION 12.1.2 Batch pre
Page 95 and 96:
76 WINE PRODUCTION Fig. 12.3 Inert
Page 97 and 98:
78 WINE PRODUCTION specialty use is
Page 99 and 100:
80 WINE PRODUCTION Must concentrato
Page 101 and 102:
82 WINE PRODUCTION Fig. 12.6 Aerati
Page 103 and 104:
84 WINE PRODUCTION Fig. 12.7 Staves
Page 105 and 106:
86 WINE PRODUCTION Micro-oxygenatio
Page 107 and 108:
88 WINE PRODUCTION 13.1.1 Size of t
Page 109 and 110:
90 WINE PRODUCTION control yet with
Page 111 and 112:
92 WINE PRODUCTION 14.1.1 Medium-sw
Page 113 and 114:
94 WINE PRODUCTION ‘by-product’
Page 115 and 116:
96 WINE PRODUCTION decades of barre
Page 117 and 118:
98 WINE PRODUCTION We know from our
Page 119 and 120:
100 WINE PRODUCTION from the smalle
Page 121 and 122:
102 WINE PRODUCTION Some smaller ho
Page 123 and 124:
104 Table 16.1 The least good years
Page 125 and 126:
106 WINE PRODUCTION of rainwater pe
Page 127 and 128:
108 WINE PRODUCTION Fig. 16.1 Toppi
Page 129 and 130:
110 WINE PRODUCTION with closures o
Page 131 and 132:
112 Table 17.1 EU permitted sulphur
Page 133 and 134:
Glossary Acetobacter. Genus of bact
Page 135 and 136:
116 WINE PRODUCTION Cask. Wooden co
Page 137 and 138:
118 WINE PRODUCTION acid into soft
Page 139 and 140:
120 WINE PRODUCTION Stelvin ® . Br
Page 141 and 142:
Bibliography Allen, M., Bell, S., R
Page 143 and 144:
Useful Websites Association of Wine
Page 145 and 146:
126 WINE PRODUCTION Wine Internatio
Page 147 and 148:
128 WINE PRODUCTION Daktulusphaira
Page 149:
130 WINE PRODUCTION veraison, 33 ve
show all

Wine Production : Vine to Bottle - Vinum Vine

Create successful ePaper yourself

Delete template?

Save as template?