do low mash temps cause starch haze?

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fluketamer

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the last two recipes i made reccomended low mash temp of 148. both beers appear to have starch haze. i normally mash higher at 154. would the low temps have caused the haze or is there something else in my process causing cloudy beer.



thanks
 
The short answer is no although you haven't provided much to go on. What's the recipe, did you use any raw adjuncts, what's the time length of the mash, were there other steps/mashout, water profile proper or different, is your thermometer accurate? By starch haze I'm assuming you're referring to chill haze. Did the haze only appear after the beer was below a certain temperature?
 
If it is actually starch haze, the lower temp mash could have been the cause, if the mash time was too short for starch to sugar conversion to complete. Both gelatinization (that has to occur before hydrolysis can occur) and hydrolysis (the chemical reaction that chops starch chains up into sugar) happen at slower rates at lower temperatures. So, lower temp mashes take longer to complete than higher temp mashes all else being equal. If you have created soluble starches, that did not complete hydrolysis, then you can get starch haze.

Brew on :mug:
 
The short answer is no although you haven't provided much to go on. What's the recipe, did you use any raw adjuncts, what's the time length of the mash, were there other steps/mashout, water profile proper or different, is your thermometer accurate? By starch haze I'm assuming you're referring to chill haze. Did the haze only appear after the beer was below a certain temperature?
no adjuncts, 9 to 10 lbs of pilsner malt. .5 lbs vienna . mashed 60 mins at 148. then mash out at 170 for 30 mins. sparged with 170 degree water. i use filtered tap water i didint measure the mineral content. i dont have that ability yet. i double check the temps with my sensor and another thermometer. no i dont think its chill haze cause it doesnt matter if thee beer is cold or not. i still am getting the cloudiness. if i leave a glass out at room temp it seems to clear a bit and leave some sediment on the bottom. the beer is clearing with gelatin but much much slower than i am used to.

this is prolly only my 12th AG batch. im starting to think i got lucky with my first 10. lol. so many more variables in AG than with extract. i am starting to doubt myself.

i think i am going to go back to a 90 min mash it seemed to give me clearer beer. and prolly mash at 154 like previously.

thanks for the replys
 
With 60 minutes at 148°F, you probably didn't completely gelatinize the starch in the grain. Then when you mashed out at 170°F for 30 minutes, you finished gelatinizing the starch, and putting a lot of that recently gelatinized starch into suspension/solution. But, you also denatured the amylase enzymes during mash-out, so that little of the recently gelatinized starch could be hydrolyzed into sugar. Thus you were left with an unusually large amount of starch in suspension/solution in your wort.

The best way to insure that your mash is "finished" is to take SG readings every 10-15 minutes after the mash has been going for 45-60 minutes. When the SG stops rising between SG readings, your mash is done as far as gelatinization and solubilization of starch is concerned. It may not yet have reached maximum fermentability, depending on the concentration of amylase enzymes remaining towards the end of the mash.

A refractometer is extremely useful for taking quick SG readings during the mash. The mash should be stirred aggressively prior to taking each SG sample (to eliminate any stratification), and the samples drawn with an eyedropper or pipette to minimize evaporation of water from the hot wort. Evaporation from the sample will give you erroneously high SG readings, and with small samples, this can be a significant effect.

Brew on :mug:
 
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With 60 minutes at 148°F, you probably didn't completely gelatinize the starch in the grain. Then when you mashed out at 170°F for 30 minutes, you finished gelatinizing the starch, and putting a lot of that recently gelatinized starch into suspension/solution. But, you also denatured the amylase enzymes during mash-out, so that none of the recently gelatinized starch could be hydrolyzed into sugar. Thus you were left with an unusually large amount of starch in suspension/solution in your wort.

The best way to insure that your mash is "finished" is to take SG readings every 10-15 minutes after the mash has been going for 45-60 minutes. When the SG stops rising between SG readings, your mash is done as far as gelatinization and solubilization of starch is concerned. It may not yet have reached maximum fermentability, depending on the concentration of amylase enzymes remaining towards the end of the mash.

A refractometer is extremely useful for taking quick SG readings during the mash. The mash should be stirred aggressively prior to taking each SG sample (to eliminate any stratification), and the samples drawn with an eyedropper or pipette to minimize evaporation of water from the hot wort. Evaporation from the sample will give you erroneously high SG readings, and with small samples, this can be a significant effect.

Brew on :mug:
WOW! Never heard/thought about monitoring the s.g. of the mash! Of course, it makes perfect sense the way you’ve described it.
I’ve been fortunate to hit my expected o.g., and typically exceed it a bit, but without any monitoring, it’s essentially a crapshoot.
This place is such a goldmine for improving my process. ❤️
 
i brewed yesterday .

9 lbs 2 row.
6 oz crystal 20
magnum/mosaic
1 pack bry 97 (dry pitch)
filtered tap

90 min mash at 154.

i used the refractometer to check the mash every so often and it helped me get a better sense of the conversion.

20 min mash out at 170
sparge was a little cooler than im used to it was only 160 but my numbers were spot on with brewers friend.
90 minute boil.
made 5 gallons of 1.051 wort 😊

i definitely mashed longer and hotter than last time so this should be a decent comparison . hopefully i make clearer beer.

thanks for the help
 
yeah i checked it every 15 mins or so with the pipette. it stopped rising after about 45 mins but i still mashed for the full 90 . cause it worked for me well in the past.

the wort was very clear but the last one was also so i think i have to wait and see.

the 2 row/ crystal 20 makes a beautiful srm 4-ish beer.

if this beer clears well it should be very good.
 
45 minutes is about what I would expect for a good crush and solid recirculation. I've always noted my wort goes quite bright by that time if not before, but I need to give the SG monitoring a try to confirm that suspicion - and whether "brightness" correlates with "done-ness" :)

Cheers!
 
sparge was a little cooler than im used to it was only 160 but my numbers were spot on with brewers friend.
Sparge water temp has pretty much zero effect on lauter efficiency. Sparging with room temp water gives the same results as sparging with hot water. The only real benefit to hot water sparging is that it reduces the time required to heat up to boiling.

Pedantic note: Hot sparging can sometimes improve mash efficiency, but that is because of increased conversion efficiency, not increased lauter efficiency. Increased conversion efficiency with a hot sparge can only happen if two conditions are met:
  1. Conversion was not complete when sparging commenced, and
  2. No mash-out was performed prior to sparging.
In the case of #1, conversion will continue during the sparge operation (up until the enzymes are fully denatured) thus leading to higher conversion efficiency. If a mash-out was performed, then there will be no active enzymes during the sparge, and thus no additional conversion occurring during the sparge.

Brew on :mug:
 
no adjuncts, 9 to 10 lbs of pilsner malt. .5 lbs vienna . mashed 60 mins at 148. then mash out at 170 for 30 mins. sparged with 170 degree water. i use filtered tap water i didint measure the mineral content. i dont have that ability yet. i double check the temps with my sensor and another thermometer. no i dont think its chill haze cause it doesnt matter if thee beer is cold or not. i still am getting the cloudiness. if i leave a glass out at room temp it seems to clear a bit and leave some sediment on the bottom. the beer is clearing with gelatin but much much slower than i am used to.

this is prolly only my 12th AG batch. im starting to think i got lucky with my first 10. lol. so many more variables in AG than with extract. i am starting to doubt myself.

i think i am going to go back to a 90 min mash it seemed to give me clearer beer. and prolly mash at 154 like previously.

thanks for the replys

It's best to put an intermediate step between 148 and 170, such as a 15 minute stop at 158F. That increases amylase activity quite a bit before denaturing. The other issue you may be having with such a light colored wort is a high mash pH which is almost an guarantee with tap water and a 4 SRM wort. A couple ounces of acidulated malt or a couple mLs of lactic acid will help. High mash pH can cause haze.
 
I agree with the posted advice. How I have learned to mash is to first determine my estimated pre-boil gravity. I always do a hoch kurz style two step mash so I stay in the beta range until I reach around 90% of the estimated pre boil gravity. I then do a 35 min alpha rest along with a 10 min mashout. I am often in beta for 70-80 minutes.

Overall, this is probably longer than most brewers here mash but the results are very solid with highly fermentable wort. The homebrew world was taught the 60 min mash thing many years ago and it stuck. When you stop and think about it, the end result is the only thing that is important and we all have different systems. So it makes sense to let the grain tell you when it is time to move to the next step, not the clock.

This is more about wort characteristics than efficiency. Having beta making up the majority of your gravity points ensures fermentability which leads to high attenuation and low final gravity numbers.

BTW, I do not think the mashout step needs to be any longer than 10 min.
 
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having 50-100 ppm's of calcium in the mash will help with clear beer. When I do a Czech Pils I have 70 ppm's in the mash but don't treat the sparge liquor to mimic the soft water of the region.
 
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