Measuring the heat of chillies
The heat of a chilli is related to the growing conditions i.e. in winter the chillies are not as hot as when grown in summer. That is why there such a big difference in Scoville ratings of the same chilli.
The modern way of tasting the heat of a chilli is using the scientific "High Pressure Liquid Chromatography" (HPLC), which to me takes away the more "organic feel" of the less accurate Scoville method.
Scoville ratings is a measure of the enzyme capsaicin which is the heat of the chilli. This test is the measure of the juice of the chilli diluted with the same amount of sugar water until no burning sensation is tasted in the mouth eg. Red Habaneros have a scoville rating about 500.000 Scoville Units, so 1 teaspoon of red habanero juice would need 500.000 teaspoons of sugar water before no heat is tasted.
A mature green chilli has a very similiar heat rating to the red version. The red chilli has a slightly sweeter heat than the green chilli. To know a green chilli is mature, break the chilli open and check weather the seeds are fully developed.
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