Pectin: Pectin is a substance in fruits that forms a gel if it is in the right combination with acid and sugar. All fruits contain some pectin, but some must be combined with fruits high in pectin or with commercial pectin products to obtain gels. Because fully ripened fruit has less pectin, one-fourth of the fruit used in making jellies without added pectin should be under-ripe.
The use of commercial pectin simplifies the process, but jelly made without added pectin contains less sugar and tastes fruitier. Acid: The proper level of acid is critical to gel formation. If there is too little acid, the gel will never set; if there is too much acid, the gel will lose liquid weep. For fruits low in acid, add lemon juice or other acid ingredients as directed. Commercial pectin products contain acids that help to ensure gelling.
Sugar: Sugar serves as a preserving agent, contributes flavor and aids in gelling. Granulated white sugar is the usual type of sugar for jelly or jam. Corn syrup and honey may be used to replace part of the sugar in recipes, but too much will mask the fruit flavor and alter the gel structure. Use tested recipes for replacing sugar with honey and corn syrup. Do not try to reduce the amount of sugar in traditional recipes. Too little sugar prevents gelling and may allow yeast and mold growth.
Tested recipes must be used to make jellies without added sugar, and these products usually must be stored in the refrigerator or freezer. Even though sugar helps preserve jellies and jams, molds can grow on the surface of these products. Research now indicates that the mold people usually scrape off the surface of jellies may not be as harmless as it seems. Mycotoxins have been found in some jars of jelly having surface mold growth.
Mycotoxins are known to cause cancer in animals; their effects on humans are still being researched. Because of possible mold contamination, paraffin or wax seals are no longer recommended for any sweet spread, including jellies.
All jellied products should be processed in a boiling water bath to prevent mold growth. Wipe the jar rim, and close with a treated canning lid and screw band. Place on a rack in a canner filled with boiling water. The water should cover the jars by at least one inch. Cover the canner. Bring the water back to a boil; boil gently for 5 minutes. Remove the jars to a protected surface and cool, away from drafts, undisturbed for 12 hours.
Altitude Adjustments: The processing times given for processing jellied fruit products are for altitudes of 0 to feet. Most areas in South Carolina will fall within these altitudes. Add 1 minute of processing and sterilizing time for each feet of additional altitude. To Extract Juice: Use only firm fruits naturally high in pectin.
Select a mixture of about three-quarters ripe and one-quarter under-ripe fruit. Do not use commercially canned or frozen fruit juices; their pectin content is too low. Wash all fruits thoroughly before cooking. Crush soft fruits or berries; cut firmer fruits into small pieces. Using the peels and cores adds pectin to the juice during cooking. Table 1 provides instructions and proportions for extracting juice from specific fruits.
Put fruit and water as instructed in a large saucepan and bring to a boil. Then simmer according to the times in Table 1 or until fruit is soft. Stir to prevent scorching. One pound of fruit should yield at least 1 cup of clear juice. When fruit is tender, strain through a colander, then strain through a double layer of cheesecloth or a jelly bag. Allow juice to drip through, using a stand or colander to hold the bag. Pressing or squeezing the bag or cloth will result in cloudy jelly.
To Make Jelly: Use no more than 6 to 8 cups of extracted fruit juice at a time. Double batches do not always gel properly. For jellies made without pectin, it is important to know whether there is enough natural pectin to form a gel.
There are three ways of determining this. Heat slowly, stirring constantly until all the sugar is dissolved. Bring the mixture to a boil and boil rapidly until it gives the sheeting test. Pour the jelly into a clean, hot jelly glass or a small bowl and let it cool. If the cooled mixture is jelly-like, your fruit juice will gel.
Alcohol Test: Add 1 teaspoon of juice to 1 table-spoon of rubbing alcohol. To mix, gently stir or shake the mixture in a closed container so that all the juice comes in contact with the alcohol. Watch it wiggle. If you've ever eaten in a cafeteria or attended a cookout or family reunion, chances are good that your dessert and salad options included some form of Jell-O.
Hundreds of recipes use Jell-O to create everything from your simple institutional-style gelatin squares to ornate designs that incorporate varied flavors, fruit and whipped toppings.
Jell-O consists of four basic ingredients:. How can one possibly mold Jell-O into so many different shapes? The gelatin in Jell-O is what allows you to get so creative — but what exactly is gelatin, anyway? Gelatin is just a processed version of a structural protein called collagen that is found in many animals, including humans. Collagen makes up almost one-third of all the protein in the human body. As you get older, your body makes less collagen, and individual collagen fibers become increasingly cross-linked with each other.
You might experience this as stiff joints from less flexible tendons, or wrinkles due to loss of skin elasticity.
Gelatin can come from the collagen in cow or pig bones, hides and connective tissues. Today, the gelatin in Jell-O is most likely to come from pigskin. Collagen doesn't dissolve in water in its natural form, so it must be modified to make gelatin. Manufacturers grind the body parts and treat them with either a strong acid or a strong base to dissolve the collagen.
Then the pretreated material is boiled. Controls at every step of the process ensure purity and safety. The materials are washed and filtered repeatedly. During this process, the large collagen protein ends up being partially broken down; the resulting product is a gelatin solution. That solution is chilled into a jelly-like material, cut and dried in a special chamber. At this point, the dried gelatin — about 10 percent water — is ground. If it's going to make Jell-O, it will be ground into a fine powder.
When you buy a box of Jell-O or another brand of gelatin at the grocery store , you get a small packet of the powdered gelatin with sugar or artificial sweetener and artificial flavorings and colors added. At room temperature, the gelatin protein is in the form of a triple helix. This is a fairly ordered structure not unlike that of DNA.
With DNA, two chains of nucleotides are twisted together in a spiral pattern resembling a ladder, in a design known as a double helix. In the gelatin protein, three separate chains of amino acids called polypeptide chains have lined up and twisted around each other. As the mixture cools, the water-rich filaments begin to bump into one another and intertwine.
The remaining water gets confined within a thicket of protein filaments and the mixture thickens into a gel. Gelatin is used in other foodstuffs like marshmallows and ice creams as well. It is also used to bind chemicals used in photographic film, in pharmaceuticals and glue.
Did people use gelatin before it was sold in shops? People made gelatin at home. And that meant boiling bones, or using isinglass, a kind of gelatin obtained from fish. But today, apart from gelatin, starch and pectin are also used to gel or thicken foodstuffs. Starch is used to thicken sauces and to make confectionaries like Turkish Delight.
Pectin, which is obtained from fruit, binds fruit preserves. Starch and pectin are types of sugars formed into long molecular chains. Also called complex carbohydrates or polysaccharides, they are excellent sources of food energy.
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