noun
Refers to the sour taste of food or drink, such as citrus, vinegar, or fermented items.
このレモンのすっぱみが料理を引き立てる。
The sourness of this lemon enhances the dish.
ヨーグルトのすっぱみが苦手な人もいる。
Some people dislike the acidity of yogurt.
Derived from the adjective 酸っぱい (sour) with the nominalizing suffix み, which turns adjectives into nouns expressing a degree or quality.