What is the peculiar bitter substance, soft or liquid, and of a yellow color, produced when meat, bread, gum, sugar, starch, and the like, are roasted till they turn brown called?

assamar — The peculiar bitter substance, soft or liquid, and of a yellow color, produced when meat, bread, gum, sugar, starch, and the like, are roasted till they turn brown. (Webster's 1913.)

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