I presently use Colmans powdered mustard in tins,powder form. Mixing a batch at a time. I have noticed it goes off after a couple of days, in a sealed jar kept in the refrigerator. Unlike the shop bought jars which last months. Can anyone give me a preservitive that I can add to the mix.

I like to mix it with 2/3 vinegar 1/3 water .... lasts ages that way .... well if it would if I ever run out of ham to eat it with...

S.J.C

Thanks for that I will give it a try. Funny you said that as I have a store boght jar from KL and I thought it had a more vinegar taste than before.

Vinegar just preserves a little bit, add a few drops of oil. Paul the chef