Simple past tense and past participle of ferment.(verb)
Produced by fermentation.(adjective)
Of food or drink, turned sour due to unwanted fermentation.(adjective)
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Use "fermented" in a sentence
"For vegan "blue cheese" recipes you need white or plain Chinese fermented or preserved bean curd."
"Instead, instructions that call for a soaking in fermented bran, whey, or ashes followed by an astringent rinse of lemon juice, verjuice or, later, oil of vitriol seem more typical. reference"
"Check it out if you're interested in fermented grape juice."