I would like to know if an addition of alcohol (such as rum or whiskey) to custard or especially the creme brulee formula, changes the temperature at which it sets. As I know from Harold Macgee's book the fact that egg proteins are dissolved in cream, as well as the addition of sugar, rise the temp to more than 175F, the addition of acid, such as lemon juice, drops the temp to about 170F, in Heston Blumenthal's lemon tart it does the job at 158F. Last time I did my creme Brulee with rum added in proportions 10g of rum and 1 egg yolk for every 100g of cream using the sous vide technique and I noticed that at 175F it curdled slightly, but the center part of the jar (where the temp reached only 158F) was silky smooth. Does alcohol speeds up the process of coagulating of the egg protein?
