ahhh -good. I was very much going to echo AndrewQLD in his sentiments.
BiaB is not the worlds most enzyme friendly process - it works just fine alright, but its probably more vulnerable to suffering from over use of starchy adjuncts.
Even with only one kg of rice - I would be targeting a malt with a good high Diastatic Power. Talk to your HB shop about it. A pilsner/lager malt rather than a pale ale malt I realize thats what you were planning to use anyway though). Andrew's suggestion of something like Galaxy is right on.
A protien rest is a temperature rest which allows the enzymes in the mash to work on the proteins in the grain not just the sugars - the particular enzymes that do that job are active in the 45-55C (ish) range and killed off at much higher than that. So a normal mash temperature in the mid 60C range doesn't really do anything much to the proteins.
Starting or resting your mash at say 50 gives the enzymes a chance to break down the long proteins that can cause haze - rice has more of these than malted barley.
So - you would aim to start your mash at about 50C, rest it for a little while, then raise the temperature up to wherever you want it for your main conversion rest.
On your first AG - if you insist on using this recipe - I wouldn't bother with the protein rest. The haze is a "maybe" not a certainty and you really will want to make your life as simple as possible. If it has a little haze - well next time you brew that beer, with some more experience under your belt - then you can do a protein rest.
Its not "hard" its just that a first brewday can be a whole lot of stuff happening at once - a complex mash schedule isn't going to make it any easier
TB
Wow too much rice mate! I thought it was a 1kg not 4kg's.
