Consistent Drop in Mash Efficiency

[BCbrewkid]

I have recently experienced an issue with my mash efficiency. I average 75-78% mash efficiency, but the last four times I have brewed I have been around 57% efficiency. I have used the same supplier for the last year and a half and never ran into this kind of a problem with this consistent of a problem. The only change I have made to my brew setup is changing the braid in my 10gal mash cooler. I was wondering if anyone might have experience with this or might have an idea of what could be going wrong.

NOTE: I order my grain to come crushed from the supplier.

Thanks for any help.

 

[airving]

Unless you're leaving behind a greater volume of liquid in your mash with the new braid, I have a hard time believing that would cause a significant drop in efficiency. Is the flow rate significantly different?

I suspect many here would say to check the crush - just because it's the same vendor doesn't mean that they haven't changed their process or equipment over time.

 

[helibrewer]

I guess the only way to prove supply vs. equipment would be to get the same grain from another source and see how that comes out.

 

[BCbrewkid]

The flow rate is the same as it was before the change in the cooler braid. I was thinking it might be the grain crush.

If the grain was old, could that have messed with the mash efficiency?

Thanks

 

[iijakii]

Grain crush would be my first guess as well.

 

[wardenwheat]

Crush of grain and length of sparge are the two most common problems. How do you sparge?

 

[BCbrewkid]

I batch sparge usually two equal batches at about 3/4 valve.

 

[wardenwheat]

My guess is if you sparge much slower 45 mins or so your efficiency will increase. It takes time to extract all the sugars from the grain. I you switched to fly sparging that may help also, but 3/4 open is really too fast to drain IMO.

 

[BCbrewkid]

I can't fly sparge at this point in time, but I will give a much slower batch sparge a shot. Just for the clarification I have always sparged at this rate and hit the higher efficiencies.

Thanks for the tip

 

[Bobby_M]

My guess is if you sparge much slower 45 mins or so your efficiency will increase. It takes time to extract all the sugars from the grain. I you switched to fly sparging that may help also, but 3/4 open is really too fast to drain IMO.

False. Speed of sparge is a fly sparge concern and not at all with batch sparging.

 

[biestie]

My guess is if you sparge much slower 45 mins or so your efficiency will increase. It takes time to extract all the sugars from the grain. I you switched to fly sparging that may help also, but 3/4 open is really too fast to drain IMO.

I disagree. As long as you have full conversion to begin with, you don't really accomplish anything by changing the length of time you take to drain your mash tun.

As for the OP, I'd call your brew shop and see if they've changed anything. You could ask them to run your grains through twice on your next batch. Alternatively, if your not set on your supplier, try Brewmasters Warehouse. Their crushes are excellent and I get better efficiency with grains from them than anywhere else. Btw, I batch sparge with the valve full open and consistently get around 80% efficiency.

If that doesn't work, I guess you could try another braid, but I don't see how that would change your efficiency.

 

[Denny]

My guess is if you sparge much slower 45 mins or so your efficiency will increase. It takes time to extract all the sugars from the grain. I you switched to fly sparging that may help also, but 3/4 open is really too fast to drain IMO.

Nope, in batch sparging flow rate doesn't matter. It can be as fast as your system will allow. It takes me 15 min. from the time I start the mash runoff til I finish the sparge runoff to get 7.5+ gal. in the kettle. I average around 85% efficiency. Going to fly sparging will not necessarily increase your efficiency. John Palmer, Gordon Strong and I discussed this on the Beersmith Homebrew Myths holiday podcast.

Beer Brewing Myths - Holiday Episode - BeerSmith Podcast 29 | Home Brewing Beer Blog by BeerSmith

 

[brewtus_]

Have the last four batches been when the weather has gotten cold? If the mash tun and grain are colder than what you're used to in the summer, if you add the same temperature water as you normally do, the mash temperature will be lower than normal affecting conversion. I assume that your measuring the mash temperature correct? If not, check it on your next batch.

 

[wardenwheat]

Like I said "a guess" I have never batched sparged, but I you fly sparge too fast your effiency will drop significantly.

 

[wardenwheat]

I guess I should have prefaced my comment by saying "you can make great beer and have great efficiency with batch spargeing" This individual has a problem with efficiency and the only thing that he has claimed he changed is his equipment, so.... maybe his equipment doesn't support batch sparging or the way he was previously doing it. That's all I was saying. We all want better beer after all.

 

[BCbrewkid]

Have the last four batches been when the weather has gotten cold? If the mash tun and grain are colder than what you're used to in the summer, if you add the same temperature water as you normally do, the mash temperature will be lower than normal affecting conversion. I assume that your measuring the mash temperature correct? If not, check it on your next batch.

I do measure, and three of the four were when it was warm out and i account for the grain temp in the strike temp calculations.