Simple syrup improves the taste of fruits and helps preserve their nice color during canning dense syrup has a lot of sugar and less water, while very light syrup uses a lot of water and only a bit of sugar. You should use light syrups because they add fewer calories from extra sugar.
You prepare basic syrups boiling water with sugar. They can have taste of herbs or fruit, or stay plain sugar and water. The basic proportion is 1:1, so one cup sugar for one cup water, that is all that is needed.
How to Make and Use Simple Syrup for Canning Fruit
Proportion of the ingredients ranges according to the wanted sweetness and thickness, but 1:1 always works well. For thikcer syrup, take two parts sugar to one part water by weight.
For canning fruits like peaches, pears or berries, various syrup weights work for different needs. Very light syrup uses 6½ cups water with ¾ cup sugar, or 10½ cups water with 1¼ cups sugar, according to the amount. For peaches you commonly choose 2:1 water-sugar proportion, although too light syrup can remove the taste.
Each syrup type comes with amounts to fill a canner load of pints or quarts.
For safe canning use at least 1:1 sugar-proportion. Pour hot syrup in sterilized jars and process with a water bath canner. Fill every pint or quart jar with fruit, cavity side down for good arrangement.
Add hot syrup, juice or water in one jar at a time, leaving ½ inch of head space.
For warm packs, boil water with sugar, add fruit, boil again and immediately fill jars. If you want syrup with whole fruit pieces, save one or two cups of fresh or frozen fruit, mix with sugar and cook like normal syrup. Remove from heat, remove the foam and fill in clean half-pint or pint jars.
The mix you can pass through a fine strainer to remove solids before pouring in jars or bottles.
If syrup has 1:1 proportion of sugar to water or juice, sugar helps to preserve it, and it stays good 4-6 weeks in the refrigerator. Light honey is a good alternative with gentle taste and clear color. Mix half honey with half granulated sugar for a good replacement.
For safety, swap up to half of the amount with another sweetener. Fruit and herbal syrups work also from jelly recipes, adding dried herbs to fruit juice and leaving pectin for syrup instead of jelly. The website of NCHFP gives reliable proportions for syrups and science about safe canning.