Mixed Grain Bill... advice sought: to malt all or not... maize, rye barley

[TheLazyWombat]

G'day Folks, 

I'm currently undergoing recipe development/R&D at the moment and am playing with a recipe which has a three grain bill: maize, rye and barley. I've got access to a good malt house that can malt the rye and maize but is there any point if using malted barley to malt the other grains? Apologies if the answer to the question is obvious... are there any pros/cons to malting all of the grains? Should I just rely on the malted barley for the conversion? I'm going to be fermenting on the grain 

[kleclerc77]

I've had lots of luck doing everything unmalted but the barley. We use a high temp Alpha Amylase enzyme for the cook up, which helps with viscosity issues as well as starch conversion. I still pitch and rest the malted barley on the way down at around 145 to utilize other enzymes present in the barley. You could accomplish conversion with only the malted barley if you nail your temps, but I like the consistency of the mash and ease of using an exogenous enzyme. I am very happy with our final product using unmalted rye and corn, but malted barley.