Before eating rice, as we know, one must recite the Beracha of "Mezonot." However, rice differs from all other foods requiring "Mezonot" in that it does not belong to one of the five principal grains (wheat, barley, oats, rye and spelt). For this reason, after eating rice one recites the Beracha of "Boreh Nefashot" rather than "Al Ha’mihya." Whereas after eating other foods that require a "Mezonot" one recites "Al Ha’mihya," after eating rice one recites "Boreh Nefashot."
Another exceptional "Mezonot" food is noodles. Generally speaking, if a person eats 8 oz. or more of a "Mezonot" food, he must recite Birkat Ha’mazon. This large quantity of grain products constitutes a meal, and thus requires the recitation of Birkat Ha’mazon instead of "Al Ha’mihya." However, this Halacha does not apply to noodles, which are boiled, rather than baked. A Halachic principle establishes that "Ma’aseh Kedera" – food boiled over a flame, and not baked in an oven – can never be considered a "meal" with respect to Berachot. As such, even if one eats an entire box of spaghetti, he recites "Al Ha’mihya," rather than Birkat Ha’mazon.
One must recite a Beracha before chewing gum. Even though one does not swallow the actual gum, the gum is coated with sugar or other flavoring that is indeed swallowed. There is no difference, then, between chewing gum and eating a small bit of sugar directly; since one tastes and swallows the sugar, he must recite "She’hakol" before placing the gum in his mouth.
This would apply also to flavored vitamins. For example, some Vitamin C supplements are orange flavored, and therefore require the recitation of a Beracha. Even though one ingests the vitamin for medicinal purposes, and not for enjoyment, he must nevertheless recite "She’hakol" since he tastes the orange flavor. Similarly, children who are given flavored vitamins must recite "She’hakol," just as they must be trained in reciting Berachot before eating food. This would hold true in the case of flavored medications, as well. Children’s medications are often flavored in the taste of bubblegum or other sweet flavors; children who take such a medicine should be instructed to recite "She’hakol" before ingesting the medicine, since they taste the sweet flavor.
Summary: One who eats rice recites "Mezonot" before eating, and "Boreh Nefashot" after eating. Generally, one who eats 8 oz. or more of a "Mezonot" food must recite Birkat Ha’mazon; in the case of noodles, however, one recites "Al Ha’mihya" regardless of how much he ate. One must recite "She’hakol" before chewing gum and before ingesting flavored vitamins and medications.
