Compounds with a Cooling Effect

A cooling feeling in the mouth is produced by both fats (cf. 14.3.2.2.2), which melt on consumption, as well as low-molecular compounds which are capable of stimulating receptors for cold perception. Menthol is well known (cf. 5.3.2.4). Its threshold for the cooling effect is 9 pmol/kg of water. In comparison with the cooling effect, however, the retronasal threshold for the characteristic menthol odor is lower by a factor of 9.5, which is a disadvantage for the wider application of menthol. 

In dark roasted malt, a-keto enamines with a cooling effect have been identified as products of the Maillard reaction. The odorless 5-methyl-4-(l-pyrrolidinyl)-3(2H)-furanone (Formula 8.1) was especially active. Its threshold for the cooling effect was 13.5 pmol/1, which is comparable with that of menthol. Studies on the relationship 

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