Canning your own homemade jams, jellies and preserves is a great do-it-yourself project. There is something so satisfying about turning plump berries, sun-kissed apricots, or fragrant peaches into a delicious spread enjoyed by the whole family. It’s like love in a jar. Making jam is also pretty simple, but it’s not always foolproof, especially for the beginner. Since I have been making jams for a looooong time, I get lots of questions not usually answered in cookbooks or online. So, in no particular order:

My cooking jam is making a mess! How do I keep it from boiling over?

This is my all-time favorite tip. Before you start cooking the fruit/sugar mixture, rub butter or margarine around the top of the saucepot. The fat keeps the jam from boiling over.

Is there any way to decrease the amount of foam that forms on the cooking jam?

Stirring constantly will keep the foam down. But that can be a lot of stirring! Adding a teaspoon or so of butter to the cooking jam will also decrease the foam. Once you have removed the jam from the heat, but before adding it to the canning jars, you can stir vigorously and usually stir the foam down. If all else fail, skim the foam off the top before putting the jam in the jars.

My Mom always used paraffin wax to top her jam, and didn’t process jam in a water bath. Can’t I just follow her directions?

I remember my mother making jam the same way, but the paraffin wax approach is no longer considered safe. Processing jam in a water bath adds an extra measure of safety and helps the jam stay good for a longer period of time. (I also remember opening a new jar of jam, removing the paraffin only to find a layer of mold- yuck!) Using the water bath method is less messy than playing around with potentially flammable paraffin too.

Even though I use butter around the top of my saucepot, the cooking jam still spits and gets all over the kitchen. Is there any way to prevent that from happeng?

I have a habit of falling into this trap too because my favorite saucepot is really too small for a regular batch of jam. Using a larger saucepot/Dutch oven will reduce and even eliminate the “sticky kitchen syndrome”.

I love to make jam, but most recipes just call for too much sugar. Can I reduce the sugar amount?

Yes and no. Old-fashioned recipes must be made with the prescribed amount of sugar. Sugar helps the jam set up, and also acts as a preservative in these recipes. Reducing the sugar amount would result in either a runny jam and/or a jam that cannot be safely stored at room temperature.

Some jams that use added pectin can be made with less sugar. Be sure to purchase the “low-sugar” specific pectin and follow the insert directions. Freezer jams can also be made with less sugar as they are preserved in the freezer.

Can I use honey or maple syrup in jam?

You can replace up to half of the sugar with an equal amount of honey or maple syrup, and cook as you would normally. Honey and maple syrup will change the flavor of your jam though, as they both have quite a bit of flavor on their own. I personally like to use maple syrup with apple spreads or anything cranberry. Honey adds a mellowness to peach that I just love.

This summer is just too hot to make jam! Can I freeze the fresh fruit and then make it into jam this fall?

Absolutely. This is a great idea, especially if you live in one of this summer’s “hot zones.” Peaches, all berries, and cherries freeze especially well. When you are ready to turn them into jam just measure out the correct amount (don’t even have to thaw) and proceed with the recipe.

Why do some jam recipes call for the addition of lemon juice and some do not?

Lemon juice is added to some fruits to increase the acid content. This is especially important if you are making old-fashioned jams that do not call for the addition of pectin. A high acid level helps the jam set, or gel, thus the addition of lemon juice! Fruit that naturally has a lower acid level (like peaches) usually needs lemon juice added. Lime juice may be added instead if you like. Lemon juice is also sometimes added to help keep the fruit from turning brown.

I want to make large amounts of jam to give as Christmas presents, but I don’t want to spend all day cooking. Can’t I just double or triple the jam recipe?

Sorry, the answer is no. Jams work best when made in small batches. Large batches of jam made at home (without commercial equipment designed for large batches) often result in burned, over-cooked jam. Stick to small batches for perfect jams and other soft spreads.

How can I tell when an old-fashioned jam or preserve is set? I always seem to overcook them.

This is a common problem, especially if you are new to cooking old-fashioned jams. There are a couple of ways to check. My favorite is to drop some of the cooking jam onto a glass plate and put it in the fridge for a minute. If the jam sets up to the level you like (there is no such thing as the “right” level, only the level you prefer) remove the cooking jam from the heat and ladle it into the jars. Another way is to drop some of the cooking jam onto a glass plate that is already cold. Draw a spoon through the jam. If the line stays separated, the jam is done. You can also check by temperature. Jam is usually set when the temperature reaches 8-9 degrees above the temperature of boiling water. Water usually boils at 212 degrees, but not always. Several things can affect the temperature including altitude and barometric pressure. So if you choose to use this method, measure to see what today’s boiling water temperature first. Otherwise you may end up with burnt jam from cooking too long.

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Disclaimer: Most of this post was originally published on my other blog. However, since I continue to get the same and similar questions, it was updated for Seed to Pantry.