Some important points to consider: Is the intoxicating ability of a substance judged qualitatively or quantitatively? If it is judged quantitative, where do we draw the line for minute amounts of ethanol produced (certain or speculatively) as a result of fermentation? E.g. you may find tiny amounts of it if you use sufficiently sensitive tools even in juices. The distinction between fermentation and adulteration. Secondary considerations about the point of intoxication. E.g. if a natural process produces so much acid in a liquid that before you reach the 'large quantity' needed to intoxicate, the acid would kill you, then do we even take theoretical points of intoxication into account? Would subsequent fermentation be tabdil al-mahiya and thus a method for dealcohilization, such as with vinegar.