Scoville scale

Wilbur L. Scoville, 1912

Scale used to estimate the degree of sharpness of substances. Originally, the degree of sharpness was determined purely subjectively, today it is determined by metrological methods. The value depends on the proportion of capsaicin contained in the dried fruit.

The degree of dilution at which no more sharpness could be determined is indicated by the Scoville degree 0. Pure capsaicin has a Scoville degree between 15,000,000 and 16,000,000 Scoville Units (SCU).

The Scoville degree defines the quantitative ratio between the liquid to be determined and the liquid used for dilution (usually water). For example, 1 ml of pure capsaicin must be diluted with 16 million ml of water to obtain Scoville grade 0 (no sharpness). Pure capsaicin is thus given the value 16,000,000 in this procedure.

The method commonly used today to determine sharpness is the percentage content of the 2 most common capsaicin compounds (capsaicin, dihydro-capsaicin) determined by chemical analysis (HPLC). The content of these two pungent drugs thus determined is then converted into Scoville Units (SCU).

Pungent drugs are used medically internally to stimulate the peristalsis of the gastrointestinal tract. They increase the secretion of digestive secretions.

On the skin they cause a dermatitic reaction and have antipruritic effects. Furthermore, they can be successfully used for chronic zoster pain (see capsaicin below).

1. González-Zamora A et al.(2013) Characterization of different Capsicum varieties by evaluation of their capsaicinoids content by high performance liquid chromatography, determination of pungency and effect of high temperature. Molecules 18:13471-1386.
2. Purkayastha J et al (2012) Molecular characterization of 'Bhut Jolokia' the hottest chilli. J Biosci 37:757-768.
3. Reilly CA et al (2001) Quantitative analysis of capsaicinoids in fresh peppers, oleoresin capsicum and pepper spray products. J Forensic Sci 46:502-509.