WHAT NOT TO CAN: Some foods are not suitable for home canning because the product itself prevents the destruction of harmful microorganisms during the canning process. Other foods interfere with the transfer of heat during processing allowing bacteria to survive. For example, the quality of delicate low acid vegetables may not be suitable after the intense heat of pressure canning.
Do not can these items unless there is a research tested recipe from a reliable source. Reliable sources include the USDA Complete Guide to Home Canning, the National Center for Home Food Preservation, Penn State Extension’s Let’s Preserve fact sheets, or Cooperative Extension websites from other states.
DAIRY PRODUCTS: Freeze dairy products, rather than can them. It is also a good idea to avoid using dairy products in canned recipes such as creamed soups, meat gravy or custard pie filling mixes. These are better prepared fresh.
EGGS: There are no research tested recipes for home canning of plain or pickled eggs for shelf storage. Commercial production of pickled eggs must meet USDA and Pennsylvania Department of Agriculture requirements for acidity throughout the product.
OIL: Oil coats any herb or food placed in it creating an ideal environment for Clostridium botulinum to grow. Avoid putting any fresh herb, fruit or vegetable in oil and sealing it in a tightly closed jar or bottle to store at room temperature. Similarly, do not can pesto. However, pesto may be frozen.
STARCH: Starch interferes with heat transfer during processing. Do not use unless specified in a scientifically tested recipe. Thicken canned products after the jar is opened for heating and serving if desired.
PASTA AND RICE: Pasta, rice, or noodles should not be added to canned products. The starch interferes with heat transfer to the center of the jar.
DENSE PUREES: The density of the product prevents heat from reaching the cold spot in the jar. You can drain the canned food and mash or puree it when you are ready to use it, or you can opt to freeze these safely.
Finally, breads and cakes should not be sealed in a jar and kept for any length of time. — Information courtesy of Penn State Extension.
