Hi I am making mustards and soon planning to do it commercially too. My question is the rate of mustard powder&wheat flour mixture ratio. Otherwise it's too hot and too expensive to sell. I welcome also other solutions to use less mustard powder. Any recommendations would highly be appreciated.
If want to sell mustard, make mustard, not a stretched fake mustard. You would be cheating your customers and depending on your location the authorities might be after you, too.
The "sharpness" of a mustard is balanced by the ratios of different mustard seeds, white/yellow, brown or black and the temperatures used during preperation. Typically, vinager is added and sometimes other flavouring compounds like other herbs, spices or honey.
There is not flour in mustard. Typical ingredients include sugars (usually brown), turmeric, paprika, garlic, and other flavoring spices. The mustard seed powder and the sugar compose most of the "structure" of the sauce. You would moderate the hotness by adding more sugar or mustard seed.