Pectin is the key ingredient for the perfect jelly. Pectin is a natural substance in plant materials that holds cell structure together. It is more plentiful in some fruits than in others, which is why some types of jelly require added pectin to form a gel or to set.
Traditional jelly or jam requires a careful balance of sugar (natural and added), acid (from the fruit itself or added lemon juice), and pectin (from the fruit and/or added) to create a gel. Before the availability of commercial pectin products, traditional jams and jellies were made by cooking fruit or fruit juice with sugar until the mixture reached a jelly-like consistency.
This was determined by the sheeting test where the jelly poured off a metal spoon in a “sheet.” A more precise method is to cook the mixture to 8 degrees F above the boiling point of water. Today, there are many types of pectin available, allowing you to make jelly and jam using fully ripe fruit in less time and with a greater yield from a given amount of fruit. Some products even allow for less or no sugar to be used. Thus, pectin is the gelling ingredient in sweet spreads.
Some jelly recipes call for other ingredients that are not pectin. These may create a tasty, sweet spread, but work entirely differently in the product. Clear Jel, Instant Clear Jel and ThermFlo are modified food starches, the purpose of which is to thicken a liquid in the same way that flour or cornstarch thickens liquids. Spreads made with modified food starches should not be canned. Those made with Instant Clear Jel and ThermFlo can be frozen. Gelatin — either unflavored (such as Knox brand) or fruit-flavored (such as Jell-O brand) — sets the product by allowing molecules to absorb liquid. Fruit-flavored gelatins may boost the flavor of a fruited jelly, but remember that gelatin dissolves when heated. Thus, jelly made with only gelatin as the setting ingredient will melt when spread over warm toast or wrapped in a baked jelly roll. Most jellies made with gelatin have a short storage life and can only be refrigerated.
Regular pectin comes in two forms — liquid and powdered. One type cannot be substituted for another. The method by which the sugar and pectin is added to the fruit is determined by the form of the pectin. In addition to making regular cooked spreads, the original pectin products include recipes for freezer jelly and jams (also called no-cook or quick and easy). Freezer jams use raw fruit and can be stored in the refrigerator for up to three weeks or in the freezer for up to a year.
Special pectin products allow you to make jelly with reduced amounts of sugar or no sugar at all. Most special pectins are low methoxyl and create the jel with calcium either as an ingredient in the package or as a separate packet that is mixed with water. Some are labeled for low sugar or no sugar and allow for the use of sugar substitutes. However, if it is for a cooked jelly, the sugar substitute must be able to withstand the heat of cooking. Sucralose is such a product. Aspartame loses it sweetness when cooked and saccharine may become bitter. Because sugar is a firming agent, products jelled with low-sugar or no-sugar pectin tend to have a softer set than those made with regular pectin. Some manufacturers suggest using frozen white grape or apple juice concentrate in place of the water in the recipe for added firmness. This takes advantage of the natural sugars in the concentrated juice. Many low-sugar products give you a choice of the amount of sugar to add; the basic recipe ranges from 0 to 3 cups. Using the higher range of sugar yields a firmer product.
No-sugar, low-sugar and artificially sweetened products do not have adequate sugar to control microorganism growth. Therefore, it is important to follow the manufacturer’s directions for processing the jelly or jam. Some have longer processing times than traditional jellies. Jars must be refrigerated after the jelly is opened.
Easy-to-use, freezer-jam pectin is made with less sugar than freezer jams made from regular pectin. Creative people can try a combination of fruits with this product. The drawback is that the consistency of the product varies with the natural pectin content of the fruit used.
For good results with any of these pectin products, follow the directions on the packages carefully. There are many choices available for any one product.
If you have food preservation questions, a home economist is available to answer questions on Wednesdays from 10 am to 2 pm, by calling 717-394-6851 or writing Penn State Extension, Lancaster County, 1383 Arcadia Road, Room 140, Lancaster, PA 17601.
The Well Preserved news column is prepared by Penn State Extension.