While it seems like everything can be canned and put away, there are some food items that are less safe to can. Many foods are great for canning, either partially cooked or raw, in order to properly store the food. Food between 2.0 and 6.9 pH levels are usually ok to can at home. Anything over 6.9, like black olives, becomes difficult to can because they have to be specially cured before the storage process begins.

Foods that Can’t

Besides the pH issues there are some other foods that make canning difficult. For instance, how gooey foods are, play into the canning process. Foods such as pumpkin and squash purees are not the best things to can.  These thick liquids make it difficult to heat through, creating cold spots in the middle, which allow bacteria to grow and become prevalent in your canning process.

Other items, which shouldn’t be canned, for much the same reason, are refried beans, butter and leafy greens, like spinach and chard also make it difficult to can due to the cold spots in the middle of the food. Creams and soups also have a difficulty with canning because, you guessed it, and they become scorched and curdled on the outside while trying to raise the temperature in the middle.