Polynomes for the relative specific activity for alpha and beta amylases

[prankster1590]

Hi,

I found this paper which describes a method of predicting the sugar composition (Glucose, maltose, maltriose and dextrins) of the wort based on the temp program during mashing.

The relative specific activity (As(T)) is basicly the factor how much more or less the amylase catalyses the reaction of the substrate at a certain temp compared to a reference temp.

The paper gives a set of polynomes that describes the relative specific activity over a range of temperatures. The problem is that when I use these equations in excel that I get a totally different graph than what is given in the paper and I dont get why.

This the one one from the paper

This is what I get for a-amylase.

What goes wrong?

This is the paper

An original kinetic model for the enzymatic hydrolysis of starch during mashing - [PDF Document] (fdocuments.in)

 

[prankster1590]

Anybody?

 

[madscientist451]

If you want to make your homebrewing a research level math project, that's cool.
My experience has been that a 152F target temperature for a 60-90 minute BIAB mash makes a pretty decent beer.
The actual making of wort is important, but more important is the recipe design, quality of ingredients and if its a hoppy beer, what variety of hops and when they are used.
Big industrial brewers can hit all their numbers all day long and produce some high quality, but boring beers.

 

[prankster1590]

Wel it was just a rounding of error. If you use like 20 decimals you get the right answers. Ofcourse this was not given in the paper, So I had to measure. This is a good approximation of the original

 

[prankster1590]

If you want to make your homebrewing a research level math project, that's cool.
My experience has been that a 152F target temperature for a 60-90 minute BIAB mash makes a pretty decent beer.
The actual making of wort is important, but more important is the recipe design, quality of ingredients and if its a hoppy beer, what variety of hops and when they are used.
Big industrial brewers can hit all their numbers all day long and produce some high quality, but boring beers.

No, im aiming for dryer. 63-64 (147 F) degrees celsius. But it is necessary to do a step to 75/76 (168 F) to gelatinize the smallest pieces of starch.

 

[madscientist451]

I suppose the answer depends on what you are starting with. If you are using unmalted adjuncts, that procedure may help.
One way to make a very dry beer is to do an overnight BIAB mash. Put it in at 152 about 10pm and go to bed, get up the next day and get the boil going.