What Is ThermFlo And Can You Use It For Home Canning?

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As summertime fast approaches, many people are filling their home gardens with warm weather crops, like tomatoes, peppers, peaches, and berries. If you're lucky, by the time autumn rolls around you'll have more produce than you know what to do with! The one downside of a bountiful harvest is finding a use for all of your delicious homegrown fruits and veggies. It's a good idea to give some away to your friends or the local food bank, and to prevent food waste even further, you might consider the benefits of canning your goods. That's where ThermFlo comes in — a powdery product that will prepare your liquid-based foods for canning.

Along with saving money and keeping your food viable much, much longer, canning is a great way to prepare pie filling in bulk so all you have to do is pour it into a pie crust. That way, you can have fresh fruit pies during any season. If you're already in the canning scene, chances are you know that you need a thickening agent to achieve an ideal filling texture. There are plenty of thickening agents on the market, but one of the most versatile options is ThermFlo.

What is ThermFlo?

ThermFlo is a kind of food additive known as a modified starch. While modified starches are occasionally derived from wheat, Thermflo is made from waxy maize, a type of corn used almost exclusively for starch. It comes in powder form, and since there is no wheat in ThermFlo, it is considered gluten free. Like other modified starches, ThermFlo is added to recipes like sauces, puddings, and pie fillings to work as a thickening agent.

This modified cornstarch can withstand both hot and freezing temperatures. This makes ThermFlo a great option for home canning since it will maintain its consistency even when the jar is put in boiling water to kill any bacteria. Products canned using ThermFlo stay food-safe for up to 12 months on the shelf, and do not change their texture even when put in the freezer. ThermFlo works with foods that are highly acidic, like blueberries, limes, and apples, as well as foods that are more alkaline like bananas and melons. Overall, ThermFlo is a safe workhorse of a thickening agent that is more than suitable for canning when needed.

How to use ThermFlo

ThermFlo can be used whenever a recipe asks for a thickening agent, such as with gravy or a glaze. You should be careful not to add a modified starch to something that doesn't need it — it won't cause you any harm, but it can ruin the consistency of a recipe. For that reason, you should follow directions exactly when adding ThermFlo and other thickening agents to a mixture.

When it comes to canning, ThermFlo is typically used to store fruit pie filling. For example, to make a simple frozen peach pie filling, add 6 pounds of sliced peaches into a pot with 2 ½ cups sugar, ¼ cup ThermFlo, and a few dashes of cinnamon and nutmeg. Stir everything together, wait until the mixture gets juicy (which will take about half an hour), then add a big splash of lemon juice. Next you will need to thicken the mixture. To do this, place the pot over medium heat. Once it becomes super thick, use a thermometer to check that it is at least 185 degrees Fahrenheit. At this point, you need to quickly cool everything down by filling a large container or sink with a few inches of cold water and placing the pot with the filling in it. Stir until cool and use freezer-safe jars to portion out the filling.

ThermFlo vs ClearJel

If you're someone who does a lot of baking, you may be familiar with ClearJel, another modified cornstarch. On the surface, ThermFlo and ClearJel are very similar, and can be used interchangeably with recipes that require a thickening agent. However, there are a few key differences. For one thing, ClearJel is better suited for use with acidic foods than non-acidic foods, while ThermFlo works well with both. And while products canned with ClearJel hold up well on the shelf, the product goes through a textural change when thawing after a freeze, so it's not recommended for frozen storage. Some users also believe ClearJel has an effect on the flavor of whatever it's added to.

ClearJel has an instant version that thickens liquids, well, instantly. Instant ClearJel freezes better than the regular variety, but because there's no cooking required, it's not recommended for use when making canned pie filling. Since canned pie filling needs to be cooked, Instant ClearJel will get too thick. When comparing ThermFlo, ClearJel, and Instant ClearJel, ThermFlo comes out on top due to its versatility and ability to withstand freezing temperatures.

Where to buy ThermFlo

Once you've prepared your kitchen for canning, it's time to begin the search for ThermFlo. You may not have noticed it before, but it shouldn't be difficult to track down ThermFlo at the grocery store. You can find it on specialty baking sites or from big retailers like Walmart and Amazon, where you can get a 2 ½ pound bag for around $24.

Canning can be a fun, rewarding project for the home cook, but it's also a big undertaking that requires a lot of care. Products like ThermFlo should only ever be used as directed to avoid a potential canning disaster. It's also important to do your research and thoroughly read labels and instructions to ensure ThermFlo is the right thickening agent for the job. Of course, your final product will make all your hard work worth it. In general, ThermFlo will work for any recipe that calls for a modified cornstarch, and it's better than its competitors when it comes to canned products intended for the freezer. So grab your fruit, sugar, and ThermFlo, and prepare to have enough pie filling to fill your freezer and your belly for months.