Author Topic: hitting the right gravity  (Read 3773 times)

Offline Phil

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hitting the right gravity
« on: October 19, 2008, 12:47:52 AM »
 ;DG'day everyone , yer just a question about hitting the right gravity pre -boil , yesterday i mashed and gravity was 1034 it was suppost to be 1049 i mashed @ 64 degrees for 75 minutes any ideas would be appreciated ;D
Life is like a beer ,not long enough
         Cheers

Offline MaltLicker

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Re: hitting the right gravity
« Reply #1 on: October 19, 2008, 06:57:37 AM »
I once later found eight ounces of speciality grains that I forgot to add in the crusher.  And I'd reconfirm the recipe and ingredients in BS to ensure what I selected in software matched my actual ingredients. 

There are two components to mashing, conversion and extraction.  First we convert "bound-up" starches into fermentable sugars of various types, and then we extract those sugars from the mash bed and grain husks. 
The degree of crush of the grains would impact conversion.  If not cracked enough, the enzymes cannot reach all the starches in the barley kernels. 
64C equals 147F, right?  This relatively low mash temp strongly favors the beta amylase enzymes.  But beta cannot break down all type starches and so a very low temp may have left some starch types unconverted.  Beta also takes longer to convert so even 75 minutes may have been too short at that temp.  And if you started at 64C and the temp slipped at all, it would have been even lower/slower.  (Calibrate the thermometer?)

The ideal pH of the mash is between 5.2 and 5.5.  If the mash pH is far outside that range it can impede conversion. 

The sparging methods to extract whatever sugars were converted are so varied it would be helpful if you posted how you sparged this batch.  Some things to note were whether you did a "mash-out," or raised the mash to 168F prior to sparging.  Cold sugars are stickier than hot sugars.  Continuous versus batch, how much sparge water, sparge water temps, and how much total water was added. 

If you posted your recipe with these details someone may spot something rather quickly. 

Offline Phil

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Re: hitting the right gravity
« Reply #2 on: October 20, 2008, 01:50:42 AM »
G'day Maltlicker,don't know about attachment posting. it is a beersmith recipe Aussie Gold Lager ,but i did the Budvar today and hit all gravity's
Life is like a beer ,not long enough
         Cheers

 

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