Could you tell us the source of these recipes please? They both strike me as personal recipes rather than tested and approved ones but I could easily be unaware of some approved ones. If they are personal or blog recipes someone made up then refrigerated storage rather than canning would be recommended.

The only "approved" thickener is Clear Jel. Cornstarch is specifically listed as a no. The Guar Gum is an unknown - never tested. In lieu of thickening prior to canning, if one doesn't want to use Clear Jel then any thickeners are added after opening the jar.

AFAIK there are only 2 approved recipes that allow for using prepared mustard in canning.

Personally I wouldn't have any problems with the first recipe simply because of all the vinegar in it but both the prepared mustard and the cornstarch will break down in processing and separate so I'd use Clear Jel instead if I was going to make it. I'd pass on the second recipe given all the flour.

But both recipes are what I call "niche" recipes - complex ingredients with minimal use and appeal - so it is difficult to justify the supplies cost and time of making them. Especially with all the needed substitutions when they can so easily be made for fresh use or fridge storage. JMO

Dave

Just to add to what has already been posted, if you decide to use Clear Jel, make sure it's the "regular" and not "instant". BIG difference!

I can see a use for a recipe like this IF I was inundated with peppers and looking for a way to preserve them beyond the usual canning/pickling. Pepper mustard would be a nice addition to a gift basket with homemade sausage and crackers or bread sticks, etc.

However, I wouldn't go buy peppers to make this when, as Dave said, it's easy to make when needed and would keep quite some time in the refrigerator.

I would be interested to know the source of the recipes as well.

Deanna