The best tips for canning sweet potatoes include those that provide a home canner with ways to maximize the potato's taste, quality, and shelf-life without compromising food safety. Small techniques used during potato selection; storage, canning, and syrup preparation; and jar filling can help to ensure that the finished product has a pleasing taste and appearance. Proper canning, preparation, and storage also preserve the food for a longer time period.
Canning sweet potatoes with optimum sweetness typically requires curing the potatoes beforehand. One to two months after harvest, store the potatoes in an area at 85° Fahrenheit (29.5° Celsius) for four to seven days. Humidity levels should measure between 90 and 95 percent during this time. After this period, lower environment temperatures to 55° to 60° Fahrenheit (12.7° to 15.5° Celsius) for storage until canning.
The type of root that you choose for canning sweet potatoes affects the end-product's quality and shelf-life. Sweet potatoes that have been cured for one week, have been harvested in the previous one to two months, and are firm and healthy at harvest make for higher-quality canned sweet potatoes. Larger sweet potatoes typically retain moisture much longer than smaller sweet potatoes, and also have a longer shelf-life when canned, especially when kept in a cool, dark place. Choose potato size according to when you'd like to use them, up to over one year for large sweet potatoes. Smaller sweet potatoes should be used within a year.
To retain the peeled potatoes' color, soak them in nearly hot water or cook them in boiling water until semi-soft while you prepare the canner for boiling. Cut the pieces to the desired size; do not mash or puree them since a safe resulting product has not been able to be achieved by the U.S. Department of Agriculture (USDA). Adding 2 tablespoons of citrus juice to the canning jars after filling them with sweet potatoes and syrup also helps with color retention, as they will have a tendency to turn brown.
Choose a customized canning syrup recipe when canning sweet potatoes that fits your tastes and dietary needs. Solutions using honey or sugar mixed with water or fruit juice add thickness, flavor, and visual appeal to canned sweet potatoes. To cut the calorie count and sugar content, packing in plain water or fruit juice is safe, so long as you follow canning instructions from a reputable source. Sugary syrup sometimes drips on the outside of the jar, so be sure to wipe down the jar with a warm, damp cloth before storing to keep things clean and avoid attracting bugs.
Filling your canning jars properly ensures your food safety and quality. Packing the cut sweet potatoes very tightly in the canning jar allows less air into the jar, especially since the potatoes shrink slightly during the canning process. Leave about 1 inch (2.54 cm) of space at the top of the jar so that a proper vacuum can form during cooling, and so that extremely hot air has some room to expand when canning sweet potatoes.