This is one of my favorite things, and I've been wanting to make some for a while, so when I saw how beautiful the California strawberries were at Sam's today, I couldn't resist them. I got six 32 oz. containers of them, which is enough to make 3 batches of eight 8 oz. jars.
After reviewing many recipes, I ended up slightly altering one from Ree Drummond.
I highly recommend that if you have never water bath canned before, you go to
http://nchfp.uga.edu/publications/publications_usda.html and read Guide 1, The Principles of Home Canning and also Guide 7, Preparing and Canning Jams and Jellies. These are the USDA National Center for Home Food Preservation recommendations for safety in home canning and they provide all the information you really need to can safely at home, however, be aware that the manufacturers of canning products, such as Ball and Kerr jars, lids, and bands, would be the absolute best place to review the most current requirements for safe canning using their products. Over years, materials used to make the sealant on lids, for example, has changed, and along with that came changes in how you can use them. Never presume a recipe posted somewhere online is safe. Use recipes from reliable sources. There are many, many posted recipes out there with incorrect methods included in the directions and also some that are not safe due to the ingredients, which may not be acidic enough for safe water bath canning. If you know up front what the correct methods are before you begin, you can proceed with confidence. Water bath canning is for food products that are acidic to a pH of at least 4.6. or lower. Even then, many recipes will include adding vinegar or lemon juice to increase acidity. It's important to follow the recipe and not omit these acidic ingredients. Processing for longer than the recommended time is not something you should do. In some cases, it can actually alter the pH of the food product. The pH of fresh strawberries is 3.00 to 3.90, making them completely safe to water bath can, and lemon juice is 2.00 to 2.60. Sugar is neutral and does not affect the pH.
I highly recommend that if you have never water bath canned before, you go to
http://nchfp.uga.edu/publications/publications_usda.html and read Guide 1, The Principles of Home Canning and also Guide 7, Preparing and Canning Jams and Jellies. These are the USDA National Center for Home Food Preservation recommendations for safety in home canning and they provide all the information you really need to can safely at home, however, be aware that the manufacturers of canning products, such as Ball and Kerr jars, lids, and bands, would be the absolute best place to review the most current requirements for safe canning using their products. Over years, materials used to make the sealant on lids, for example, has changed, and along with that came changes in how you can use them. Never presume a recipe posted somewhere online is safe. Use recipes from reliable sources. There are many, many posted recipes out there with incorrect methods included in the directions and also some that are not safe due to the ingredients, which may not be acidic enough for safe water bath canning. If you know up front what the correct methods are before you begin, you can proceed with confidence. Water bath canning is for food products that are acidic to a pH of at least 4.6. or lower. Even then, many recipes will include adding vinegar or lemon juice to increase acidity. It's important to follow the recipe and not omit these acidic ingredients. Processing for longer than the recommended time is not something you should do. In some cases, it can actually alter the pH of the food product. The pH of fresh strawberries is 3.00 to 3.90, making them completely safe to water bath can, and lemon juice is 2.00 to 2.60. Sugar is neutral and does not affect the pH.
Here's what you need to make 8 jars of delicious strawberry jam:
5 cups hulled mashed fresh strawberries (2 32 oz. containers - you will have some left over, so as you mash or process the strawberries in batches, pour into a measuring container so you can stop when you get to 5 cups. Use the leftover whole strawberries for something else.
7 cups sugar
4 tablespoons lemon juice
1 4.9 oz. package powdered fruit pectin
Directions:
Find the freshest strawberries you can!
Wash and remove the tops from the strawberries. I put mine in the food processor and processed them by pulsing until they were to the consistency I prefer. I didn't want big chunks of fruit in my jam, but you can either mash them or process them to whatever level of "fruit chunkiness" you want! The food processor went quickly and I think it saved me some time.
I used one of my mixing bowls with measurements to pour the strawberries in as I processed them. This is 5 cups.
"Processing" is defined as the entire length of time the filled jars are at a full, strong boil.
Before you start the cooking process with the strawberries, place eight clean 8 oz. mason jars into a large hot water bath canner. Be sure you have checked the jars for cracks or flaws at the rim that may prevent a proper seal. Don't use a jar if either of those things are present. Cover the jars with water by one to two inches (minimum of 1 inch), and simply get the jars hot, bringing them to a good simmer so they won't break when you put the hot jam in them before processing. Processing times vary depending on the altitude you're at, so be aware and adjust your processing times accordingly. Because the jam will be processed for a full 10 minutes at the altitude I live at, it isn't necessary to sterilize the jars - they will process long enough to kill all bacteria in the jam and on the lids and jars., but if it makes you feel better about safety, you can go ahead and sterilize them if you so choose. To do that, boil the jars for 10 minutes prior to filling them with jam.
Old guidelines suggest to place new, never used lids into a small pot of water and bring to a simmer - do not allow them to boil. Once they simmer, lower the heat to the lowest setting just to keep them hot, to prepare them for use in canning. This is no longer necessary if you are using Ball or Kerr products. Manufacturing materials for the sealants on lids changed years ago, eliminating the need for this. But again, if it makes you feel better, go ahead, it won't hurt, but never boil the lids. Please see my January 2018 post on Current Guidelines for Canning Lids for details as to where this up-to-date information comes from if you question it.
Now it's time to get those strawberries cooking!
Place all the strawberries and all 4 tablespoons of lemon juice into a large pot. Stir to mix, then stir the pectin in until dissolved. Bring to a strong boil, stirring frequently. I actually stirred mine constantly just to make sure it didn't stick to the bottom or burn, but I have no idea if that's actually necessary. Don't panic about the foam, that's normal! Once you have a good strong boil, add all of the sugar, stirring as you pour it in. It sounds like lots of sugar, but don't use less, the sugar, along with the pectin, is an important part of what helps the jam gel. (There are recipes for low sugar jams you can use if you don't like the idea of this much sugar, and there is also a Sure Jell pectin product especially made for lower sugar jams). Stir to mix well, then continue to stir until you have a full rolling (violent) boil that won't stir down. Then continue to stir and boil for an additional full 1 minute and 30 seconds, using a timer, or, if you are not confident about being able to establish if it will gel properly or not, use a thermometer and boil until it reaches 218 to 220 degrees. Note: You can boil the jam for a shorter length of time if you want a fruit sauce instead of a jam. It's great for pouring over ice cream, other desserts, and I use it to swirl into things like muffin batter or my cheesecake batters, and even use it to spread on top of my cheesecakes sometimes. I can tell by how it coats the spoon I'm stirring it with whether it's at a good "sauce" stage, but I learned that method by way of a trial and error phase, so I won't make any recommendations!
Next, turn off the heat and quickly skim as much of the foam off the top as possible, and you are ready now to begin filling the jars. It helps to have all your equipment ready to go before you start. You will need regular tongs, a jar lifter, a clean towel to sit the jars on as you fill them, a ladle, a canning funnel, a clean damp cloth or paper towels, new clean lids, and a plastic headspace/air bubble reducing tool. If you have a canning kit, everything you need will be included.
Remove one jar at a time from the water with tongs, pouring the water in the jar back into the pot. Leave the burner turned on at the simmer level while you do this. Fill each jar with jam leaving a 1/4 inch headspace at the top. Use the head space tool to measure so you are leaving the correct amount of head space for the recipe. Use a funnel while doing this. It saves time because you don't have as much cleaning to do on the jars. You may want to stir the jam in the pot a time or two during the process just to make sure you are keeping the liquid/fruit ratio consistent as you fill the jars.
You can run the air bubble reducing tool around the interior of each filled jar to help eliminate air bubbles, (it doesn't actually matter with jams and jellies), then wipe the rims of the jars off with a damp cloth or paper towel to remove any jam that would prevent the lids from sealing properly. Place a lid on the jar, then a screw band, being careful not to over-tighten the band. Twist the band just until you feel resistance and stop. Repeat with all jars, then place jars on canning rack and lower into the water. Make sure the jars are covered with at least one inch of water. Add water if necessary, and remove any water over 1 to 2 inches above the jars. More water than you need in the canner just takes it longer to come to a boil. Put the lid on the canner and turn up the heat to high. Bring to a full boil. Once a full hard boil happens, put a timer to 10 minutes and allow to boil for that long. Don't fail to use a timer, and don't start the timer until the water is in a full strong boil. You can off set the lid slightly if water begins to spew out during the processing time.
Turn the heat off when the timer goes off and allow the jars to remain in the hot water for an additional 5 minutes, then remove them using a jar lifter, taking care to not allow the jars to tilt and to keep the lifters placed on the glass when lifting, not the band, and allow them to sit on a towel on the countertop undisturbed for 24 hours. Do NOT tighten the bands! There will be water on the tops of the lids. Don't wipe the water off, just allow it to remain there. Most of it will evaporate and what doesn't can be wiped off once the jars are fully sealed. After 24 hours, check to confirm they all sealed. There should be no movement or give whatsoever on the lids. If any of them failed to seal, place them in the refrigerator and use them first. This is unlikely, but possible. I've never had a jar fail to seal properly. The most common cause of a seal failure is when a jar tilts or falls over onto it's side in the pot before you lift it out to cool. Because it isn't sealed yet, jam can get into the space between the lid and the jar rim and prevent a proper seal.
Once the jars are completely cooled and you have checked for proper seals, do not tighten the bands on the jars. This can actually compromise the seal. The band should only be tightened after the jam has been opened to use and refrigerated. Until then, the bands should remain loose but intact. Some people prefer to remove the bands when they store their jars. There is no harm in doing so, however, I don't recommend stacking jars on top one another when storing whether you choose to remove the bands or not.
Add identifying labels to your jam that include a "best if used by" date. Kerr has new "Sure Seal" jar lids that make a better seal allowing you to go 18 months for a "best if used by" date, but if you aren't using those, 12 months from the date you make the jam is the date to use.
All that's left to do is store your yummy jam in a cool dark place, such as your pantry, or... share it with friends and family!
I've finished 2 of my 3 batches. I have to make a mad dash to the grocery store for more pectin. I thought I had enough, but I was WRONG, shucks!!! I'll finish my last batch tomorrow.
