You can’t successfully can horseradish sauce at home for shelf-stable storage. The volatile oils in horseradish that give it its kick are destroyed by heat.
You can however make horseradish sauce for cold storage — either refrigerator or freezer.
Jars: As this is not a canning recipe per se, you may use any size jar you want. The recipe suggests 1/4 litre (1/2 US pint / 8 oz) jars. The jars will need lids. As this is for refrigerated storage, this is where you could use antique jars (that still close properly) or Le Parfait jars, etc.
Yield: 2 x quarter-litre (1/2 US pint) jars
Wash horseradish roots and peel.
Grate the roots.
Mix all ingredients together and pack into clean sterlized jars.
Screw lids on jars tightly.
Store in refrigerator.
The ascorbic acid / lemon juice is optional; it's to help prevent browning.
The optional drop of liquid stevia is to round out flavour.
Australia and New Zealand vinegar strength special notes.
A bit of sweetener can help to round the taste out. We’ve suggested white sugar; you could try Splenda or a few drops liquid stevia. For stevia, we’d recommend Better Stevia liquid stevia .
You could use a salt sub; we’d recommend Herbamare Sodium-Free .
The lemon juice / ascorbic acid is there to prevent darkening. Ascorbic acid does a better job of doing this while not impacting flavour, but we put lemon juice first as an ingredient as more people are likely to have it to hand.
Pickled Horseradish Sauce. In: United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. Page 6-30.
- Pickled Horsradish. In: Ball Blue Book. Muncie, Indiana: Healthmark LLC / Jarden Home Brands. Edition 37. 2014. Page 152.
- Prepared Horseradish. In: Ziedrich, Linda. The Joy of Pickling. Boston, Massachusetts: The Harvard Common Press. 2009. Page 363.
- Turned ascorbic acid into an option and put lemon juice instead because lemon juice is more common;
- Added Ziedrich’s suggestion of a bit of sweetness “to smooth the flavour”.
Serving size: 1 tablespoon
Per 1 tablespoon: 9 calories, 0 mg sodium
Weight Watchers PointsPlus®: 1 to 2 tablespoons, 0 points; 3 to 6 tablespoons, 1 point.
* Nutrition info provided by https://caloriecount.about.com
* PointsPlus™ calculated by healthycanning.com. Not endorsed by Weight Watchers® International, Inc, which is the owner of the PointsPlus® registered trademark.
* Better Stevia ® is a registered trademark of the NOW Foods Company.
* Herbamare ® is a registered trademark of the A. Vogel Corporation.
Comparison of ways to grate horseradish roots
We compared four ways to grate horseradish roots and these were the results:
- Food processor: purée;
- Food mill: stringy like shredded cheese;
- Blender: square little chunks;
- Hand-grater: perfect consistency
The hand grater proved the best way.
Here are the visual results.
Tips for making horseradish sauce
According to the University of Minnesota Extension, the longer you let the horseradish sit grated before adding the vinegar, the hotter it will get, up to about 3 minutes. At that point, it will have hit maximum hotness, if that is what you are after, and you add the vinegar.  Herman, Marilyn. Making Horseradish. University of Minnesota Extension. 2001. Accessed March 2015. It won’t get any hotter after 3 minutes.
How strong it was to start with will depend on the freshness of the roots. If you purchased the roots from a grocery store, then all bets are off for how long the roots were in a cold-storage warehouse before being trucked to distributors.
Horseradish will lose its hotness in the fridge. It will still be somewhat hot after a month, milder after two months, and quite mild after three months.
It will also darken in storage in the refrigerator.
A little sweetener such as stevia can help to smooth the flavour; a bit of ascorbic acid (or Ball Fruit-Fresh Produce Protector) can help alleviate the browning.
Don’t necessarily expect to save any money by making your own, if you are buying the roots. The roots can be expensive to buy, so count yourself lucky if you break even on making your own from purchased roots versus buying prepared bottles. The taste of homemade, though, is better than store bought, as you would expect, so you will be ahead that way, and the store-bought can be very high in added sodium.
You can freeze jars of homemade horseradish in the freezer (in straight-edged, freezer-safe jars, or plastic tubs.)
Some people note that the Japanese successfully make dried horseradish powder (wasabi powder). The University of Minnesota’s extension service, however, says it’s not worth trying to dry or dehydrate horseradish. “Drying will not produce a successful product.”  Herman, Marilyn. Making Horseradish. University of Minnesota Extension. 2001. Accessed March 2015. They do not say in which regard.
If you want a creamed horseradish sauce, stir some double-cream or sour cream into the prepared horseradish sauce when serving.
Horseradish’s role in canning
The FDAs table of “Approximate pH of Foods and Food Products” assigns a pH value of 5.35 to freshly ground horseradish  FDA. Center for Food Safety and Applied Nutrition. Acidified and Low-Acid Canned Foods. April 2007. Accessed March 2015 at https://www.foodscience.caes.uga.edu/extension/documents/fdaapproximatephoffoodslacf-phs.pdf. so it counts as a low-acid ingredient on its own, not made into a pickled sauce.
Some old-timers think that horseradish can play a firming role, but the jury is out on that still. Linda Ziedrich says,
Horseradish is not only a traditional pickle flavoring, it’s also said to be a firming agent. From my limited trials, I suspect that horseradish may help prevent the softening of fermenting pickles by inhibiting yeast growth. The fresh pickles I made with horseradish, however, were noticeably softer than those I made with alum, grape leaves, and our cherry leaves. Unfortunately, it seems that no scientist has done a proper study of horseradish in pickling. So I suggest using abundant amounts of grated or chopped horseradish with fermenting cucumbers to see what happens (let me know!), but none at all with fresh pickles unless you happen to like the mustardy flavor.” Ziedrich, Joy of Pickling, Page 18
Many pickle, relish and chutney recipes, etc, call for the addition of horseradish to add some heat and kick to the recipe, presumably. The problem is, the heat of horseradish cannot withstand — heat. The late Alan Davidson, author of the Penguin Companion to Food wrote:
The pungent odour and hot taste of horseradish are due to a substance called sinigrin which, when it is decomposed by the action of enzymes, liberates a volatile oil, similar to mustard oil, containing sulphur. The release of these properties only occurs when the root is cut or bruised, an unbroken root has no smell…. Horseradish sauces are usually uncooked or only gently warmed. Heat destroys the pungency, and when whole horseradish roots are cooked as a vegetable, which they occasionally are in Eastern Europe, the flavour is quite mild.”  Davidson, Alan. The Penguin Companion to Food. London: The Penguin Group, 2002. page 464.
So while some flavour of the horseradish may come through, little to no “kick” or “pungency” actually will.
In the classic French sauce, “Albert Sauce“, horseradish is boiled for 20 minutes. The sauce ends up with a horseradish background taste, but not the pungency or heat.
Ziedrich appears to imply that horseradish may have slight preservative properties — “Like mustard oil, horseradish cointains the pungent chemical allyl isothioyanate, which has been proven to kill food pathogens.” Ziedrich, page 363. But pursuing that line of thinking or the science behind it is beyond the scope of this page at this time.
References [ + ]
|1.||↑||Herman, Marilyn. Making Horseradish. University of Minnesota Extension. 2001. Accessed March 2015.|
|2.||↑||Herman, Marilyn. Making Horseradish. University of Minnesota Extension. 2001. Accessed March 2015.|
|3.||↑||FDA. Center for Food Safety and Applied Nutrition. Acidified and Low-Acid Canned Foods. April 2007. Accessed March 2015 at https://www.foodscience.caes.uga.edu/extension/documents/fdaapproximatephoffoodslacf-phs.pdf.|
|4.||↑||Ziedrich, Joy of Pickling, Page 18|
|5.||↑||Davidson, Alan. The Penguin Companion to Food. London: The Penguin Group, 2002. page 464.|
|6.||↑||Ziedrich, page 363.|