In the previous post I mentioned my thermometer problems. I have a new thermometer on the way that will solve my thermometer issues. For now, I have beer that's too thick. I can live. I'll have to make a session beer soon, since the amber that I was looking forward to appears to have stopped fermentation at a dextrinous 1.020. That session beer will either be inspired by Rogue's American Amber or Left Hand's Sawtooth Ale. The former case will involve dark crystal and special B malts on a 2-row base with a neutral but strong bitterness, the later, lighter crystal, munich and 2-row and less bitterness. I'll probably do the finishing hops as I desire, rather than try to imitate their finishing hop profiles exactly.

Anyway, there's a certain liberation that comes from these failures, as I'm now re-commited to my step-mashing program but, since I've yet to implement it, I can reconsider how I will go with it. The plan is that each beer have a two-step conversion, one at 145 and one at 155 followed by a mash out (protein rest optional.) The 155 rest is invariably 45 minutes, while the 145 rest time is varied to control the fermentability of the mash. It seems to me that in practice, the 155 rest need not be so long if the 145 rest is long; most mashes don't need to exceed 1 hour. The thought I'm toying with is that once I've established the results of these various step-mash procedures, I'm going to trying reducing the length of the 155 step for those mashes with a 30+ minute 145 step.

I've considered reducing the temperature of the 145 step. The goal of that step is primarily to use beta-amylase to produce maltose; secondarily it is to gelatinize the barley. There's no reason to be bothered by the other amylase activity. Then I decided against this while trying to find a curve of activity of limit dextrinase as a function of temperature; I discovered this while following a citation in Palmer. The conclusion of this article is that limit dextrinase activity is more strongly correlated with wort fermentability that either alpha- or beta-amylase activity, and the abstract quotes 63-65 degrees C (145-149 F) as maximizing limit dextrinase activity in actual mash conditions. I didn't order the article, so I can get into the details of it, however, I suspect that because of the low levels of limit dextrines available during the early parts of a 145 rest, the activity of limit dextrinase will be less important. However, for a long mash, it will become very important. This also suggests the importance of the rest to 155 for conversion completion: limit dextrinase activity will quickly cease because it is 5 degrees from it's preferred temperature range and two degrees warmer than its denaturing temperature.

I want to make a beer now.