“Sugar serves as a preserving agent, contributes flavor, and aids in gelling. Cane and beet sugar are the usual sources 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 yeasts and molds to grow.”
To learn more about making jams and jellies go to: http://nchfp.uga.edu/how/can7_jam_jelly.html. The uga stands for University of Georgia and, if you use their guidelines in the amount of time to process as well as the amount of pressure to use, please be aware that University of Georgia is at sea level and you need to make altitude for preserving food at our higher altitudes.
Please refer to page 9 of the Ball Blue Book Guide to Preserving for the altitude chart on using the boiling-water method as well as the pressure method. The page number I am referring to is found in the new edition that was put out this year.
It says: “Boiling-Water Method. The processing times given in this book for high-acid foods are based on canning at or below 1,000 feet above sea level using the boiling water method. When processing at altitudes higher than 1,000 feet above sea level, adjust the processing time according to this boiling-water canner chart.” The chart shows that for those of us who live at 3,001 to 6,000 feet in altitude we should increase the processing time by 10 minutes. If you are at 6,001 to 8,000 feet you should increase the processing time by 15 minutes. For those water bath canning at 8,001 to 10,000 feet to increase the time by 20 minutes.
Pressure Canning: “The pounds pressure given for low-acid foods . . . is based on using a weighted gauge canner and processing at or below 1,000 feet above sea level. When using a dial gauge canner or processing at altitudes higher than 1,000 feet above season level, adjust pounds pressure according to this pressure canner chart: Altitudes 1,001- 10,000 feet should use the 15 pound weighted gauge. If you use a dial gauge, the adjustments are as follows: 2,001 – 4,000 pressure can at 12 pounds; 4,001 – 6,000 use 13 pounds; 6,001 – 8,000 use 14 pounds and 8,001 – 10,000 use 15 pounds.”
If you use the United States Department of Agriculture (USD) Complete Guide to Home Canning, the adjustments are already figured in the charts that accompany each recipe.
To me, it is fun to problem solve what happened in your preservation and to understand the why, so you don’t repeat the ‘oops’. Please call your Nutrition and Food Safety Extension Educator so that together we can work out the answer to your question.
(Sources: Ball Blue Book, United States Department of Agriculture (USD) Complete Guide to Home Canning)
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