Red wines come in different colours: deep purple, ruby, garnet (generally the lighter the colour, the older the wine); white wines: golden, lemon (yellow), pale with green tinge (the older the wine, the deeper the colour). Wines should be bright in colour. Wine Leg is a phenomenon in which droplets drop slowly along a wine glass, a sign of wine with a high alcohol content. This does not mean the wine is of higher quality; there are other factors to consider.

Smell the wine to see any aroma in there. Aroma is a descriptor of young wines with fruit flavour, while bouquet is for mature wines with sign of development. With a little imagination you can describe the aromas of wine you taste. In general fruit flavour for red wines include blackcurrants, blueberries, plums, strawberries, cherries, raspberries etc. Floral aromas of red wines include roses, violets, flowers etc. Spices include cinnamons, cloves, and black pepper etc. Vegetal notes with green capsicum, herbs; oak barrel notes include toast, coffee, smoky developed into tea leaves and tobacco with age. For white wines, there are aromas such as grapefruits, oranges, peaches, almonds, floral, grassy; sweet white wines come with aromas like honey, apricots, and dried fruit.

After a sommelier pours you a wine, you first have to smell it to get the first impression of the wine. Then swirl the glass gently to let it get more in touch with air. Then smell the wine again. Do not swirl the glass too much, or the aroma will simply be gone.

A wine has gone bad if it smells rotted, strange, like vinegar, rotten eggs, or corks.

Generally speaking, sweetness is to be found in white wines. Acidity in wine is affected by wine regions: the hotter the climate, the higher level of sweetness and so lower the acidity. For red wines, high content of tannins will bring about astringency. Tannin comes from the skin, seeds, and stems of grapes. Tannin is an important component to the complexity and ageing of wine. With times, they become soft and smooth and even silky. In regard to alcohol, the higher level of alcohol the fuller the body of wines, but it doesn't mean the quality of wine is higher. Nevertheless, the more complex a wine is, it needs a certain level of alcohol to balance the fruitiness, tannin and acidity. While acidity makes wines lively and refreshing, otherwise they will taste more like juices. A good quality white wine is refreshing and pleasant and a good red is smooth, with a lingering finish.