Berakhot 128

2:
The mugmar referred to in our mishnah is a receptacle containing burning aromatic spices – similar to in incense that one can see used in Roman Catholic and Greek Orthodox worship to this day. After the meal, these aromatics were brought to the table to create a pleasant smell: the function of the mugmar, although rather different in nature, was very similar to the modern "air-freshener". Just as one is required to recite a berakhah over food so we are required to recite a berakhah over pleasant smells and perfumes – just as we do over the perfume used during the Havdalah ceremony at the end of every Shabbat. The person designated to recite Grace after the Meal out loud for the benefit of all the diners was also the person who recited the berakhah over the wine that came after the meal and over the pleasant smell of the mugmar.

In Berakhot 125 we learned:

When taking one glass of wine during the meal we might have no intention of taking any more – and then subsequently change our minds. Therefore, states the Gemara, on ordinary days each glass of wine taken during the meal requires its own separate berakhah. There is another difference too." Which is not the case on Shabbat and Yom Tov.

Jeff Silver writes:

I can think of one glaring exception to the exemption of wine taken after the meal: Cups 3 and 4 at the Sedarim – Or is the entire Seder considered as one meal?

I respond:

Jeffrey Smith also noticed this point.

No, this is not the case because the entire Seder is considered as one meal, but because each of the four cups stands in its own right. These cups of wine are not "voluntary" – if you want to drink wine do so and if you want to refrain do so also. These four cups are "required". The Mishnah [Tractate Pesaĥim 10:1] is quite emphatic on this point: "Even a Jewish pauper must eat reclining, and may not be given less than four cups of wine – even if they come from the communal charity kitchen". Each of the four cups of wine is deemed to be parallel to a separate verb in Exodus 6:6-7. Thus each cup stands in its own right, and the drinking of one of them does not obviate the duty of drinking the others.

David Bockman writes:

It occurs to me that the question of berakhot is not directly linked to taxonomy. After all, we normally understand kashrut as linked to taxonomy: milk, meat, pareve, treif, organs, etc. And yet all these classifications are subsumed under only one berakhah, except for produce of various kinds, which in kashrut terms are non-issues. In terms of berakhot, however, plants are shown to have tremendously complex taxonomy, while that of the animal world is ignored! To be consistent, either plants should be differentiated vis-a-vis kashrut, or, what would make more sense, animals, dairy, etc, should have their own special berakhot. The only answers I can come up with regarding this question are that the berakhah taxonomy is intentionally omitted when dealing with animal products because

1. the animal life issue (not celebrating the fact the animal had to die to give us food by saying a berakhah) or
2. the "already having made a berakhah" (at the time of shchita, although this would then makes us wonder about Terumah and ma'aser and challah) issue.

The third possibility has to do with the epistemology of eating, i.e. forcing us, through the process of preparing to eat our food, to face the complexity of God's universe. If we have sufficiently been forced to realize, through selecting menu items that must be of certain differentiated types, that God's mercy is expressed in a vast multitude of ways, we may content ourselves with a simple berakhah acknowledging that fact (She-ha-kol). If, on the other hand, we eat "undifferentiated (vis-a-vis kashrut selection) foods", we must force ourselves, through the process of berakhah classification, to think of "kama ma'alot tovot la-makom aleinu".

BTW, I heard that the Bostoner Rebbe used to eat a banana at his seder as the karpas, just so he could teach his hasidim that it was "pri ha-adamah" and grew on a "bush".