Expert: John Snyder - 7/17/2004

Question
Thanks for ur answer
i hope u remember me , i am a malster and i have been asking on malting.Today again it is a problem for me.i supply malt to different breweries initially we were not facing any problem but very recently we have been brewers have been complaining about ph value being around 5.8 to 6.0. Since i am at the receiving end i would request u that if it is actually a problem for them how can i improve it at the malting level and keep the levels within the specifications (5.5 to 5.7)
thanks
best regards.

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Followup To
Question -
dear sir,

How does PH value effects the brewing.My customer has given me a range of 5.5 to 5.7. Generally it is observed in between 5.7 to 5.9.

How does it effect the brewing process and how can i maintain it at the malting level.

regards,

Answer -
pH values affect the mash program,affect extract yield,hop bitterness,malt flavor,beer foam,fermentation,yeast growth,resistance to bacterial growth,hot and cold break,oxidation.

Mash pH should be in range of 5.3 to 5.6 at 70F which is the same as 5.0-5.3 at 160.F
Malt ph is normally 6.0
runoff pH should be in same range as mash initially and not rise over 5.8-6.0

Calcuim ion content of brewing liquor has a major effect on wort pH,which falls as the calcuim level rises.Both mashing and sparging liquor should ideally have calcuim contents between 100 and 200ppm.

Phosphoric acid can be added to the mash water,or sparge water,but it is important to measure pH of the mash and runoff

Salt composition is very important. Calcium sulfate can be used to adjust Calcium

At what stage is this pH range of 5.5 t0 5.7 your customer wants?

What do you mean maintain it at the malting level,not sure of your terminology?

Any further info needed i will be glad to assist.  

Answer
As stated earlier malt pH is around 6.0,with the min being 5.1 and the max 6.2.Alpha- Amylase activity,and beta-Glucanes,are mainly responsible for Ph changes in the process.AS you know the germination period creates the enzymes needed.This stage is normally in the range of 4 to 6 days,followed by kilning,to terminate the germination.
Modification is the key.Evidently your customer has a specific set of enzymatic action he wants,to produce a specific brew etc.The customer,i would think should tell you what malt specs he wants;Ex extract,protein,diastasic power etc.this would then allow you to adjust your germination time,etc to meet his specs,or any other stage of the malting process.