I have bought two packs of diastatic barley malt flour in the months since I asked this question. With the first 1.5 Kg packet I was using 2 - 3 teaspoons. I ran out of that, and a few weeks later I got a 3 Kg for about the same price as the 1st 1.5 Kg. My recipe is continuously evolving, but now to get my preferred level of maltiness I am using 60g. While I have not accurately weighted 2 - 3 teaspoons (see this question for my problem) I am sure it is less than 15g, possibly much less.
I am fairly sure the difference cannot be purely accounted for by my change in taste. I balance the amount of malt by is to get the taste malty but avoid the bread being too gooey, and my current recipe is not too gooey, by a long way.
It is plausible that the second batch of diastatic barley malt flour has a vastly lower enzymatic activity than the previous pack? Is there another obvious explanation for this observation? Is there a way to objectively test the activity of diastatic malt?
If it is relevant, my current basic bread mix is 60g diastatic barley malt flour, 60g wheat gluten 80g wheat bran and 180g wholemeal flour. This is added to a breadmaker bowl after 3/4 tablespoon sugar, 1 teaspoon salt and 1 egg. 1 teaspoon yeast is added on top and the basic 1.5 lb cycle is run.
