Sinalbin is metabolised to form the mustard oil 4-hydroxybenzyl isothiocyanate by the enzyme myrosinase. The less sharp taste of white mustard is because 4-hydroxybenzyl isothiocyanate is unstable and degrades to 4-hydroxybenzyl alcohol and a thiocyanate ion, which are not pungent. Half-life of the isothiocyanate is depending on pH of the solution –  longest time is 321 minutes at pH 3, and lowest is 6 min at pH 6.5. Glucobrassicin is a structurally related glucosinolate that likewise yields a non-pungent isothiocyanate due to reaction with water.
Sinalbin is metabolised to form the mustard oil 4-hydroxybenzyl isothiocyanate by the enzyme myrosinase. The less sharp taste of white mustard is because 4-hydroxybenzyl isothiocyanate is unstable and degrades to 4-hydroxybenzyl alcohol and a thiocyanate ion, which are not pungent. The half-life of the isothiocyanate depends on the pH of the solution – the longest time is 321 minutes at pH 3, and the shortest is 6 minutes at pH 6.5. Glucobrassicin is a structurally related glucosinolate that likewise yields a non-pungent isothiocyanate due to reaction with water.
R
Half-life
The half-life
R
is depending on
depends on the
A
the
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lowest
the shortest
R
min
minutes