barrels or casks and the client would fill their pitcher or bottle. Glass bottles revolutionized the wine industry. The absence of transfer and thus contact with the oxygen in the air has made a significant improvement to the quality of the product. Other containers have emerged: aluminum cans, Tetra Pak cartons, plastic bottles, and the bag-in-box. Their quality is in their chemical inertness in relation to wine and their hermetic character against oxygen. The wine bottle has been given certain shapes dedicated to wine. The most emblematic is the bottle of sparkling wine: because of the pressure inside it is a fairly thick glass. Many countries have adopted this shape for bottles of white wine – a more streamlined form than red wine bottles. Wine tasting Colour The colour of white wine is as varied as the types of wines. The term most commonly cited is yellow. However, the richness of vocabulary leaves free space for visual analysis between the actual colour and the hue (the range of colour is often different at the joint between the wine and the glass). At the end of the 20th century the components of the wine which made the colour were still not clearly identified. Over the ages the flavones in the grapes were considered responsible for the yellow colour but their very low dissolution in wine, due to short maceration, led to a search for other molecules. A thesis by Biau in 1995 alluded to the influence of polysaccharides, proteins, and some phenolic acids. Léglise specified that: "the term gold is used if the appearance is very bright and full of reflections, in the definition of the various nuances specific to the metal (...) If, with proper clarity, the wine does not shed light and does not radiate reflection, we will give only the term yellow". On a colour scale white wine can be almost colourless white. When young it usually takes on a pale greenish or pale yellow tint. Its yellow colour darkens with age and maturing becoming gold, then copper, and finally amber. One of the darkest wines in the world is achieved with a white grape: the Pedro Ximenez. The ratio of sugar also affects the colour of the wine making the colour more sustained, depending on the nature of the grape varietal: a Bordeaux Sauvignon blanc or a Muscadet Melon have a greenish tint while Chardonnay or Traminer