Hello! 1) What is the time limit for saying "Amen" to someone’s bracha? If you don’t say it immediately, could you hypothetically say it 10 seconds later or longer, etc.? 2) What is the time limit for making a bracha achrona after bread, but also after other types of foods? 3) If you start eating something without a bracha, can you then make a bracha halfway through? Thanks!
Shalom, Thank you for your great questions! 1. The time limit for saying amen to someone's blessing is within "toch kedai dibur" – the minimum measure of time in relation to speech. It is the time it takes to say "Shalom Alechah Rebbi [Mori]". This is only the time of a few seconds. When hearing a blessing in a congregation one may answer as long as long as the majority of the congregation has not finished saying "amen". (See Shulchan Aruch, Orech Haim 124, 8 and the Mishna Brurah 34). 2. One may say an after blessing as long as the food has not completely digested, after this stage one may no longer say the after blessing (See Shulchan Aruch, Orech Haim 184,8). In general we say with bread that this takes up to 72 minuets. (There are many details about this law, but if you try to always remember to say birkat hamazon at the end of the meal, or at least within 72 minuets you will be safe). With other foods one also has the same 72 minuets. But, all this is only true if one ate to satiation. If one at a smaller amount, such a piece of fruit between meals, then there is some doubt as to how long one may say the after blessing. You should try to say it straight away, or at least within half an hour, but if you only recalled later, you may rely on the same 72 minuet rule (see Mishna Brurah ibid 20). 3. If one accidently started eating without a blessing, one must stop eating and say a blessing on the remaining food. Blessings.