The Complete Handbook of Quince

Chapter 1: Understanding Quince

1. What Quince Is: A Pome Fruit with Unusual Rules

Let's start with what you actually have in front of you. Quince (Cydonia oblonga) is a pome fruit, like apples and pears, but it operates under different rules than its better-known cousins. The fruit is hard, yellow, and irregularly shaped. When you take a bite of a raw quince, you'll notice two things immediately: the astringent, mouth-drying sensation and a gritty, woody texture. This is not a defect. It's the fruit's natural defense mechanism, and it dictates everything you need to know about how to handle quince commercially or as a serious hobbyist.

The astringency comes from tannins. The grittiness comes from stone cells, which are clusters of lignified cells called sclereids. These stone cells are far more abundant in quince than in any commercial apple or pear variety. You will not remove them by peeling. You will not remove them by cooking. They are structural components of the flesh. The only way to deal with them is to either cook the fruit for a very long time (which breaks down some of the structure) or to put the flesh through a fine sieve (which physically separates the grit from the smooth puree). Understanding this simple fact will save you from countless failed recipes. The famous quince paste, or membrillo, is not a "reduced jam." It is a suspension of pureed, sieved, and highly concentrated flesh that has been cooked until the natural pectin