משנה אויף ויקרא 10:9

Within what time must he eat them [for him to be liable]? [The time he would need] if he ate a similar amount of parched grains of corn, the words of Rabbi Meir. But the rabbis say: he must take from the beginning to the end [of his eating] no more time than is required for the eating of a peras (a half a loaf of bread) [to be liable]. If one eats unclean food or drinks unclean drinks, or if he drinks a quarter [of a log] of wine and then enters the Temple [he is liable if it takes less time] than it takes to eat a peras. Rabbi Eliezer says: if the drinking was interrupted or if he diluted it, he is exempt.

Three things are forbidden to a nazirite: ritual defilement, shaving, and products of the vine. All products of the vine join together [to add up to a minimum measure], and he is not liable until he eats an olive’s worth of grapes. According to the earlier mishnah, until he drinks a quarter [of a log] of wine. Rabbi Akiba says: even if he soaked his bread in wine and it is enough to make an olive’s worth he is liable.