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"Before I make jam, can I find out how much pectin is in the fruit?"

Hi Anne and Sue,

Is there any way of determining the pectin content of fruit before making jam or jelly? Then I would be able to find out if a fruit would set without added pectin.



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Dear Theresa,

Yes, there is a test using rubbing alcohol that provides a rough indication of the amount of pectin in fruit juice.

Alcohol Test: Mix 1 teaspoon of cooked, cooled fruit juice with 1 tablespoon of rubbing alcohol. Use a closed container and shake gently. Juices rich in pectin form a solid jellylike mass that can be picked up with a fork. However, juices low in pectin form only small jellylike particles, so such fruits require powdered or liquid pectin in order to set.
Caution: Do not taste the fruit-alcohol mixture, as rubbing alcohol is poisonous. Just throw it away, and wash all your utensils well.

While pectin naturally occurs in fruit, the amount can vary. Fruits such as citrus, tart cooking apples, cranberries, and quince are high in pectin. Fruits such as late-season blackberries, cherries, and nectarines, are at the low end of the pectin scale. Apricots, peaches, rhubarb, and strawberries, among others, are classed as medium in pectin content. The pectin content in all fruit is also generally higher when fruit is just barely ripe and diminishes as it matures from fully ripe to overripe.

Pectin can't work alone, however. Without the correct proportions of acid and sugar, jams or jellies won't set. These proportions vary according to the fruit you're using. Thus, using tried-and-true recipes when making jams and jellies generally gives a much higher quality product than if you're trying to ad-lib.

Homemade preserves taste so special come winter!

Anne & Sue


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