In order to make the blessing of “al netilat yadayim” for bread we must eat a kabeiyah (an egg size). This is 2 zeisim( 2 olive sizes). Does one have to eat this kabeitzah within the time of “kedei achilas pras” (3 minutes), or can one just eat 1 kaziyit kedei achilas pras, and the the other kezayis later or within the meal?
There is no need to eat the full kebeitzah amount within the short time frame of kedei achilas p’ras, and it can be eaten at leisure throughout the meal. Netilas yadayim was enacted for a proper meal, which demands the eating of a kebeitzah, but does not demand that this amount be eaten in a specific time frame.
At some stage of the meal, a kezayis must be eaten within the required time frame, so that the obligation of birkas hamazon will be incumbent; it is preferable to eat this kezayis at the beginning of the meal.
Although there are different opinions as to the length of kedei achilas peras, which range from 2 to 9 minutes, for the purpose of the meal one can rely on the opinion of 4 minutes.