Post by admin on Oct 6, 2006 1:40:52 GMT -5
www.extension.umn.edu/foodsafety/components/columns/Oct17.htm
Apples, potatoes and pumpkins have produced well this year. Canning them for later use is popular and so is sharing canning recipes. The Internet is another popular way to share recipes. Here are some of the outdated and risky recipes and methods that have been floating around this year.
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Canning potatoes in a hot boiling water bath canner (outdated recipe). Why is this risky? Pressure canning is the only safe method of canning low-acid foods like vegetables, meats, poultry and seafood. Clostridium botulinum bacteria are the main reason why these low-acid foods must be pressure canned to be safe. The spores of Clostridium botulinum can only be killed at temperatures of 240 degrees F. This temperature can only be reached in a pressure canner.
Current Recommendations: Place potatoes in a pan of hot water, bring to a boil and boil whole potatoes for 10 minutes; cubes for 2 minutes. Drain. Pack hot potatoes in hot jars and fill jars to one-inch from the top with fresh boiling water. Process in a Dial Gauge Pressure Canner at 11 pounds pressure or in a weight gauge pressure canner at 14 pounds. Process pints for 35 minutes and quarts for 40 minutes.
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Apple juice (outdated recipe) – “One ice cream bucket (5 quarts) of cut up apples and 2 tablespoons of cream of tarter. Cover with boiling water and let stand overnight. Drain and can or refrigerate.” Why is this recipe risky? Apple juice is a high acid food. Adding cream of tartar makes it more acidic. However, letting the juice “stand overnight” at room temperature may allow acid tolerant yeast and bacteria like E. coli 0157:H7 to grow.
Current recommendations: USDA/Extension recommends purchasing the juice from a local cider maker for best results. We don't have methods for pressing the juice - just canning it. There are consumer apple presses available. Ease of clean up and sanitation needs to be considered. Basically, pressing requires lots of time and effort and is messy. The University of Tennessee Agricultural Extension Service developed a fact sheet called, “Home Apple Cider Production” you can download it at www.utextension.utk.edu/publications/spfiles/SP307O.pdf.
Homemade apple juice or cider should be pasteurized—heated to 160 degrees F—before drinking, refrigerating or canning. If you purchase it from a local orchard, ask if it’s been pasteurized. Many times apple cider or juice is made from apples that have been on the ground. The apples can become contaminated with E. coli bacteria from deer, cattle, bird or mouse droppings. To pasteurize at home, heat the juice or cider in a pan on the stove to 160 degrees for six seconds while stirring constantly. If you don’t have a food thermometer, heat to boiling (stirring constantly) and immediately remove the pot from the stove.
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Canning apple pie filling using tapioca or cornstarch as the thickener (outdated method.) Why is this risky? Botulism is not a major risk here because the high acid content of the apple filling. However, using cornstarch or tapioca may cause the filling to be too thick for the heat to penetrate and kill spoilage organisms throughout the product—a food safety issue. Cornstarch will break down during the canning process. Your pie filling will be runny—a food quality issue.
Current recommendations: Clearjel® is the only thickening agent approved by the USDA for canning. Clearjel® is a modified waxy food starch producing a smooth, heavy-bodied, gel-like product. Canned products retain a smooth texture with no liquid separation or curdling. Cornstarch and tapioca break down during the canning process causing the filling to be runny. Clearjel is available on www.sweetcelebrations.com or 1-800-328-6722. Another option is to can the pie filling without any starch and then thicken it with tapioca or cornstarch before putting it in the pie shell.
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Canning mashed or pureed pumpkins and squash (outdated method). Why is this risky? Pumpkins and winter squash are low acid foods and need to be canned using a pressure canner. Canning pureed or mashed pumpkin is a not safe because you have a solid mass. It will take too long for the heat to reach the center of the jar during processing.
Current Recommendation: Cubing the squash or pumpkin is a safe practice and allows for quicker heat transfer throughout the product. Freezing is an option for pureed or mashed pumpkins and squash.
Apples, potatoes and pumpkins have produced well this year. Canning them for later use is popular and so is sharing canning recipes. The Internet is another popular way to share recipes. Here are some of the outdated and risky recipes and methods that have been floating around this year.
--------------------------------------------------------------------------------
Canning potatoes in a hot boiling water bath canner (outdated recipe). Why is this risky? Pressure canning is the only safe method of canning low-acid foods like vegetables, meats, poultry and seafood. Clostridium botulinum bacteria are the main reason why these low-acid foods must be pressure canned to be safe. The spores of Clostridium botulinum can only be killed at temperatures of 240 degrees F. This temperature can only be reached in a pressure canner.
Current Recommendations: Place potatoes in a pan of hot water, bring to a boil and boil whole potatoes for 10 minutes; cubes for 2 minutes. Drain. Pack hot potatoes in hot jars and fill jars to one-inch from the top with fresh boiling water. Process in a Dial Gauge Pressure Canner at 11 pounds pressure or in a weight gauge pressure canner at 14 pounds. Process pints for 35 minutes and quarts for 40 minutes.
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Apple juice (outdated recipe) – “One ice cream bucket (5 quarts) of cut up apples and 2 tablespoons of cream of tarter. Cover with boiling water and let stand overnight. Drain and can or refrigerate.” Why is this recipe risky? Apple juice is a high acid food. Adding cream of tartar makes it more acidic. However, letting the juice “stand overnight” at room temperature may allow acid tolerant yeast and bacteria like E. coli 0157:H7 to grow.
Current recommendations: USDA/Extension recommends purchasing the juice from a local cider maker for best results. We don't have methods for pressing the juice - just canning it. There are consumer apple presses available. Ease of clean up and sanitation needs to be considered. Basically, pressing requires lots of time and effort and is messy. The University of Tennessee Agricultural Extension Service developed a fact sheet called, “Home Apple Cider Production” you can download it at www.utextension.utk.edu/publications/spfiles/SP307O.pdf.
Homemade apple juice or cider should be pasteurized—heated to 160 degrees F—before drinking, refrigerating or canning. If you purchase it from a local orchard, ask if it’s been pasteurized. Many times apple cider or juice is made from apples that have been on the ground. The apples can become contaminated with E. coli bacteria from deer, cattle, bird or mouse droppings. To pasteurize at home, heat the juice or cider in a pan on the stove to 160 degrees for six seconds while stirring constantly. If you don’t have a food thermometer, heat to boiling (stirring constantly) and immediately remove the pot from the stove.
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Canning apple pie filling using tapioca or cornstarch as the thickener (outdated method.) Why is this risky? Botulism is not a major risk here because the high acid content of the apple filling. However, using cornstarch or tapioca may cause the filling to be too thick for the heat to penetrate and kill spoilage organisms throughout the product—a food safety issue. Cornstarch will break down during the canning process. Your pie filling will be runny—a food quality issue.
Current recommendations: Clearjel® is the only thickening agent approved by the USDA for canning. Clearjel® is a modified waxy food starch producing a smooth, heavy-bodied, gel-like product. Canned products retain a smooth texture with no liquid separation or curdling. Cornstarch and tapioca break down during the canning process causing the filling to be runny. Clearjel is available on www.sweetcelebrations.com or 1-800-328-6722. Another option is to can the pie filling without any starch and then thicken it with tapioca or cornstarch before putting it in the pie shell.
--------------------------------------------------------------------------------
Canning mashed or pureed pumpkins and squash (outdated method). Why is this risky? Pumpkins and winter squash are low acid foods and need to be canned using a pressure canner. Canning pureed or mashed pumpkin is a not safe because you have a solid mass. It will take too long for the heat to reach the center of the jar during processing.
Current Recommendation: Cubing the squash or pumpkin is a safe practice and allows for quicker heat transfer throughout the product. Freezing is an option for pureed or mashed pumpkins and squash.