There are more than 300 varieties of chillies of which more than 100 are indigenous to Mexico. They vary in length from 5mm to over 300mm, some are long and narrow, and others plump and globular and they vary in heat from mildly warm to mouth-blisteringly hot.

Small chillies are hotter be- cause they contain proportionally more seeds and membrane.

If the heat gets to you then the answer is a glass of cold milk, not beer. Casein, a protein found in mild products, breaks the bond between the pain receptors and the capsaicin.

At different stages chillies are correctly called berries, fruits, vegetables and spices.

Birds cannot taste the hotness in peppers and the very small peppers known as "bird peppers" are often eaten whole by birds. The bird's gizzard breaks up the pods and the seeds pass through undigested and surrounded by a nice nitrogenous fertilizer. Mammals on the other hand are discouraged by the extreme hotness of the bird peppers.

The chilli is a rich source of vitamin C, even more so than the lemon or orange. Even after cooking it only loses 30 percent of its vitamin C. It is claimed to be effective in protecting against cancer, being a powerful anti-inflammatory and helps to decongest the respiratory system.

Scoville units were invented in 1912 to measure the heat of chillies. This is achieved by measuring the amount of capsaicin in a diluted solution of alcohol and sugar-water. To achieve a rating it takes three out of five people to detect the heat. The rate of dilution is the Scoville unit. Therefore if 60 percent of the testers can detect any heat at a dilution of one part per 2 500 parts of solution then the rating would be 2 500 Scoville units which is what a jalapeno pepper would achieve. Habanero peppers could be rated at up to 300 000 Scoville units ... very, very hot!

Red pepper "bombs" have been successfully used in Cameroon's Waza National Park to stop herds of elephant from straying out of the park. The elephant, which have a keen sense of smell, found the spray from the bombs so offensive that they re- treated deep within the park.

There is no difference between red and green chillies. Generally, the green chilli is harvested early and the red is left to change colour and ripen.

In cold weather a little chilli powder sprinkled into your socks will keep your feet warm all day. Experienced skiers use this trick but it also works if you don't wear ski boots.

A chilli sweetens as it turns from green to red and becomes milder and that's something to keep in mind when you're using Thai curry paste - the red pastes are milder than the green ones.

Chilli is the most popular spice in the world and psychologist Paul Rozin has suggested that in spite of the fact that it is an irritant to us it is an example of a "constrained risk", like riding a roller coaster. The hotness make our body respond with warning signals, but because the situation is not genuinely dangerous we can ignore the meaning.

Tabasco, the famous sauce, is only one of thousands and is by no means the hottest.