One of the mandates in our house is to use the whole food as much as possible while we are preserving it, also known as a zero-waste recipe. This year, we were able to source an amazing price for ears of corn (17 cents an ear), and we couldn’t pass it up. We decided to make a dozen 454g bags of frozen corn. During this time, I posted in threads about the process we were using to cook, freeze, and package the corn. More and more people started to suggest we use the cobs to make corn cob stock. What? I had never heard of such a thing. I immediately searched how to make corn cob stock. There wasn’t a lot out there, and much of it varied on cooking times, how to preserve it, etc. My ADHD intrigue set in, and I spent the next several hours trying to find recipes and instructions on how to process the cobs and then preserve them through pressure canning. What you are reading here is my interpretation of this process.
Corn Cob Stock
Equipment
- Stock pot
- Sharp knife
- Cutting board
- Storage depends on how you save the stock
Ingredients
- 4 ea. Corn cobs or whatever you actually have on hand.
- Water, enough to cover
Instructions
- Place corn cobs, with corn removed, into a stock pot or pot large enough to hold the stocks in. You should use a pot that the stocks fit into fairly well, not much room to move around. Having too much water will dilute the stock.
- Cover cobs with about 1 cm or 1/2 in of water.
- Bring to a boil, then reduce to a rolling simmer for 30 minutes.
- Remove cobs, let cool, then filter.
Preserving the corn cob stock.
- Option 1 – Fridge: Cool down quickly (throw a couple of ice cubes in), then put into Tupperware and keep in your fridge. You will have a two-week window to use it based on prior experience with stocks. You will need to make your own judgment call on this, though. If it’s slimy or has a film, it’s best to throw it out before you use it.
- Option 2 – Freeze: Cool down quickly (throw a couple of ice cubes in), then put it into a storage vessel or ice cube trays. Freeze and use as you would like. Frozen products start degrading but are safe for up to a year. Freezer burn can remove a lot of moisture.
- Option 3 – Pressure Canning: Pressure canning is the only viable option to make this shelf-stable without using a lot of chemicals. If you haven’t pressure canned before or aren’t 100% sure how to do this, I would highly suggest learning beforehand. Because this is a veggie-based stock, you will need to pressure can according to your manufacturer's instructions. I used a fairly standard time of 60 minutes at 11 lbs of pressure to ensure shelf stability. You really have to know elevations, etc. Pressure canning is an amazing tool; it can be a little worrisome when you first start, but once you get the hang of it, it gets easier.
- Not an Option – Water Bath Canning: ABSOLUTELY DO NOT DO THIS… You cannot water bath can this and make it shelf-stable. This is incredibly unsafe; the product does not have a remotely low enough pH to do this. Even adding vinegar would not be sufficient. Trust the science.
The first thing you will need to do is source some sweet corn. Once the ears are in hand, start a large pot of water, set it to boil, and add salt to the water. While impatiently waiting for the pot to boil, you will need to shuck and clean the corn. Remove any parts that may be bad; bruised products can ruin the end result. Once the water is boiling, drop your ears of corn in and blanch for 4 minutes. Have a bath of cold water ready to immediately stop the cooking process when you remove them from the boiling water. If you want to know more, this is the best article I found on blanching: University of Minnesota Extension, Freezing Sweet Corn: Whole Kernels. This was what I used as the basis for blanching.
Once the corn has been blanched and cooled, remove the kernels with your method of choice. There are many different ways to accomplish this simple task. If you are using a knife, be careful and make sure it is sharp. Once you have removed all of the corn from the cobs, place them into a pot. I used a lot of cobs because I had them and a large pot. You can do this with as few as 4 cobs, though, easily. Once you have the cobs in the pot, pour water over them until they are covered by about 1 cm. Turn your stove on high and let the water come to a boil. Once boiling, turn the stove down to a strong simmer and let the cobs cook for 30 minutes, or however long you feel is enough.
Once the cooking is completed, turn off the heat and remove the cobs. Because I have a lot of kitchen tools at my disposal, I was able to filter out the corn pieces that were in there. If you have a fine strainer, use that to pour your stock through once.
We didn’t add any seasoning to the stock while cooking it. While you can, of course, we tend to add our seasoning at the time of actual use. The reason behind this is that you never know what you will be making, and if it’s already a heavily salted/seasoned meal, adding more salt might ruin all the hard work you’ve already put in.
What can you use this for? While I’ve only just made it, I can already see a myriad of uses in the kitchen. I’ve also received an amazing number of suggestions through our thread community:
- Use it as a tea; apparently, in some areas of East Asia, this is common.
- Cornbread, polenta, corn muffins, etc.
- In soups where it calls for vegetable stock.
The next steps are up to you depending on how much you cooked, your experience, and the tools you have.
Option 1 – Fridge: Cool down quickly (throw a couple of ice cubes in), then put into Tupperware and keep in your fridge. You will have a two-week window to use it based on prior experience with stocks. You will need to make your own judgment call on this, though. If it’s slimy or has a film, it’s best to throw it out before you use it.
Option 2 – Freeze: Cool down quickly (throw a couple of ice cubes in), then put it into a storage vessel or ice cube trays. Freeze and use as you would like. Frozen products start degrading but are safe for up to a year. Freezer burn can remove a lot of moisture.
Option 3 – Pressure Canning: Pressure canning is the only viable option to make this shelf-stable without using a lot of chemicals. If you haven’t pressure canned before or aren’t 100% sure how to do this, I would highly suggest learning beforehand. Because this is a veggie-based stock, you will need to pressure can according to your manufacturer’s instructions. I used a fairly standard time of 60 minutes at 11 lbs of pressure to ensure shelf stability. You really have to know elevations, etc. Pressure canning is an amazing tool; it can be a little worrisome when you first start, but once you get the hang of it, it gets easier.
Not an Option – Water Bath Canning: NO… You cannot water bath can this and make it shelf-stable. This is incredibly unsafe; the product does not have a remotely low enough pH to do this. Even adding vinegar would not be sufficient. Trust the science.
