White wine the death knell of northern viticulture. The vine disappeared from northern Germany and Baden, and the maximum altitude for viticulture descended to 220 metres. Hans-Jürgen Otto noted that: "all the vineyards suffered and decreased in area". In England the vine also disappeared. The less early vineyards preferred to select white varieties of grapes because, even if unripe, white grapes allowed wine that was a little sour to still be consumable, while red grapes do not give enough colour and green tannins make the wine bitter. The interruption of the fermentation by a cold winter led to the discovery of the
Colour recovery colour programmes were lost. However, in the case of the BBC, many telerecorded black & white film copies of affected programmes survived. These black & white copies were made for overseas commercial exploitation of BBC programmes. For a variety of technical and practical reasons (for example various incompatible international TV standards, and the then-high cost of videotape over that of film), black & white film copies were the preferred medium for selling programmes overseas. This practice ultimately led to many programmes which were originally made and transmitted in colour only existing in black and white form after the practice of