National Homebrew Club Ireland

Brewing Discussions => All Grain Brewing => Topic started by: imark on April 12, 2013, 12:22:25 PM

Title: Mash enzymes effectiveness
Post by: imark on April 12, 2013, 12:22:25 PM
Question: If you're outside the ranges for alpha or beta amylase can you compensate with extended mash time? Or looking at it a different way, to what extent does the enzyme's range taper off?

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Title: Re: Mash enzymes effectiveness
Post by: UpsidedownA (Andrew) on April 12, 2013, 01:47:38 PM
QuoteQuestion: If you're outside the ranges for alpha or beta amylase can you compensate with extended mash time? Or looking at it a different way, to what extent does the enzyme's range taper off?

(http://www.howtobrew.com/images/f79.gif)


Were you thinking about pH or temperature ranges? My understanding was that with pH, the optimum pH really is the optimum, in the sense that that is where they work best, but they can still function albeit less effectively (slower) outside the range. With temperature on the other hand, there isn't such a thing as a true optimum in that reaction rates will increase with increasing temperature but the enzymes will fall apart and denature quickly when you take them above their official ranges. So, e.g. you could take beta-amylase up to 70 and it would work flat out, but would probably all be used up after five minutes, whereas it could work for 30 minutes nearly as quickly at 65 degrees. So, in answer to your question, you CAN compensate with extra time for pH and for low temperatures, but you cannot compensate with extra time for above range temperatures.
Title: Re: Mash enzymes effectiveness
Post by: imark on April 14, 2013, 10:42:38 AM
The upper temperature denatures them. I would have guessed there would be a ph equivalent also?
Title: Re: Mash enzymes effectiveness
Post by: UpsidedownA (Andrew) on April 14, 2013, 12:47:30 PM
As far as I know, a pH out of optimum zone does not denature enzymes.