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...some very phenolic compounds are used as replacemants in cases, such as the soaps, where vanillin cannot be used because it rapidly turns chocolate-brown
之前有听堂主说过香草是香料氧化变色的重灾区，指的应该就是这回事了。
Natural vanilla extract contains lots of phenolic notes, and smells a bit like a fresh exotic-fibre carpet or smoky, wet tea leaves. This is desirable, because pure vanillin is a little too clean all by itself, and needs a bit of phenolic raunch to perform at its best in perfume. Indeed, when Jacques Guerlain used vanillin in fragrances, he always choose a somewhat impure grade which smelled nicer (the firm of De Laire sold it to ihim for more than the pure stuff). He then mixed, say, ten parts of this stuff to one of the expensive vanilla absolute to make it both cheap and rich.
娇兰在Guerlinade基底里面专用的是有杂质的vanillin这一点之前也有所耳闻，原来所谓“杂质”的本体就是phenol，一种有烟熏感和焦油味的分子，合成vanillin的主要原材料的guaiacol的近亲。