The ideal strategy is to use an ALDH inhibitor. There are many food-based options available.
Mescaline is deaminted to it's aldehyde mostly by SSAO (with minor MAO-B involvement).
This aldehyde is oxidised mainly by Aldehyde dehydrogenase (ALDH).
If ALDH is inhibited, mescalines aldehyde metabolite can react with endogenous amines to form active substances.
There are many naturally occuring amines in the body, from ammonia to dimethylamine and phenethylamine.
It is likely that secondary amines are relevant here, including piperidine, dimethylamine and pyrrolidine. Levels of these amines can be influenced by diet. The amino acids lysine and arginine are converted by gut bacteria into piperidine and pyrrolidine respectively. Choline serves as the precrusor for dimethylamine.
With an effective level of ALDH inhibition, a dose of mescaline is much more effective.
Increasing levels of the endogenous amines mentioned above will influence the metabolites produced, and the nature of the experience.
Reports indicate that pomegranate extract/juice works well as an ALDH. There is a mention of pomegranate on this forum in the context drug potentiation. The poster was focusing on carbonic anhydrase inhibiton and seemed unaware that ALDH inhibition might have played a key role in his results.
I've made a mescaline-optimising salad using pomegranate, pistachioes, peas and parsley (there may have been some other ingredients - @downwardsfromzero has posted the recipe somewhere, I think). It was very tasty, and may even have worked to some extent.
Won't ALDH inhibition mean that pomegranate worsens hangovers - but maybe improves LSA/LSH experiences as well?