Estimating BIAB Efficiency on smaller scale?

[arnobg]

I started crushing my own grain and haven't brewed yet since.

Could I do a 1 gallon trial brew to calculate my efficiency of what I'm extracting from the grain and scale it to 5 gallons to know what I'm working with, or are there too many other variables?

I'm just looking for a baseline to estimate utilization from mashing grains so I know how much to adjust for in the recipe to hit my OG.

 

[UndeadFred]

I did a pint mash before my first BIAB and got about 75% conversion efficiency with mashing in the microwave just to get a feel for it, so sure you can do a gallon. If you want the batch to be a gallon you will need to mash about a gallon and a half of water give or take... Just scale it down.

 

[Bellybuster]

Set your efficiency at 75% and you'll be fine for full size batch. I wouldn't be surprised if you hit those numbers bang on at that setting. Even if you are off by a bit, it will still be beer. Good beer

 

[arnobg]

My first 5 gallons batch with LHBS crush was about 79-81% efficiency and my crush looks just as good if not bette. If I try to brew a light beer that I have planned next I afraid I'll overshoot by a lot and have a 6% beer that was supposed to be around 4%

 

[pricelessbrewing]

It's going to depend on the grain bill, water volumes, and sparge method as well. If you're going to this as a test batch, make sure your mash thickness and sparge method are the same.

As a good baseline, you can use the link in my sig to get an estimated mash efficiency. Unless you've measure you've measured otherwise, input a conversion efficiency of 92-95%.

 

[Oginme]

It seems to be a reasonable way to get a starting point and to help with adjusting your crush without committing to a larger batch. I do 10 liter, 16 liter and 20 liter BIAB batches and find that my mash efficiency is pretty consistent independent of batch size. As has been mentioned above, you want to make sure that what you do on a small scale mimics what you would do on a larger scale.

 

[wilserbrewer]

While you could certainly try and predict your efficiency using smaller trial batches, it sounds like quite a hassle to me. I also wouldn't wager that your small batch will be spot on with a larger batch.

I would just check gravity and volume preboil and make an adjustment if needed.

If your gravity is low, extend the boil, if high throw some wort out and add water, or live with a tad stronger beer.

Not splitting atoms here fellas lol

 

[doug293cz]

For the test batch to give you a good prediction, you not only need to use the same sparge, or no-sparge, process as @pricelessbrewing notes, but you also need to hit close to the same grain absorption rate (gal/lb). Absorption rate depends on how well you drain/squeeze your bag. The chart below shows how efficiency varies with grain absorption rate. Chart assumes 5.5 gal post-boil and 6.7 gal pre-boil gravities.



The lauter efficiency needs to be multiplied by your starch conversion efficiency to get your mash efficiency.

Brew on