well this is a discussion that we keep coming back to. yesterday I brewed a recipe using BIAB with a dunk sparge. a couple weeks ago I brewed this squeezing the bag and my gravity was a tad low like 5pts yesterday I did no squeeze and gained the 5 pts. Now of course we know it can be many things but last night I was thinking about it and that is the only thing I did different. I had thought I did this expieriment before
I used to squeeze. In fact, as it was handing, I’d twist the bag. I didn’t have gloves and what a sticky mess “that” was…
Sneezles61
Well i use gloves but did you ever notice a difference in extraction?
This is interesting. Was the 5 point difference in gravity measured pre-boil or post-boil? And how much extra wort volume do you get from squeezing the bag?
Post boil. I generally have about a half gallon of water leftover if I squeeze. So this time I used all the water. I got to my target volume and the just hung the bag over a bucket. About a cup of wort drained that I didn’t use. Didn’t check the gravity of the leftover
I’ll need to look at my notes. I suspect tho, if I would stay with that routine, then I must have…
Sneezles61
Did you measure your final volume? If you squeezed this time you could have certainly ended up with more volume and collected a weaker OG wort.
I do measure my volume and target the same amount. I could have squeezed and got more wort but that would change the OG. Normally I’ll use 3/4 of my water mash pull the bag and squeeze. Then measure and only use the amount of water needed to reach my volume for the dunk and squeeze that to get my calculaed volume. The only reason I didn’t squeeze this batch was I inadvertently used all my water
Normally my gravity is pretty close with the sqweeze these batches back to back could have been as simple as sloppy weighing of the fermentables
pH the same too?
Sneezles61
I don’t check pH anymore but water and grains were all the same so probably. Just an anomaly, could be alot of things. Same grain different lot maybe. Its not a problem just opening a discussion since the sqeeze no squeeze never gets resolved. When I started BIAB a while back I thought I had better results squeezing but maybe that was also an anomaly. So my takeaway is I’m not squeezing anymore unless my volume is short. So the liquid left in the grain is money in the bank if my volume is low
I’m now using a basket… well, have been for quite some time… my basket is on a pulley system so I get it just to the top and let it drip… I’ll use my mash paddle to stir it as well. My brew house efficiency remains around 80%… BUT, the volumes need to be correct.
So does that circle us back… volumes, weights need to be closely adhered too in order to validate gravity outcome ?
Sneezles61
Ahhh, I read it backwards. From my understanding grains will absorb some of the sparge water while sparging. Therefore, when squeezing your squeezing a much lower gravity wort. I also think that it’s system and technique driven. If you are getting your desired OG and volume with dunk sparging leave it as is. If you are getting a higher than desired OG with less volume then squeeze to get your desired OG and volume.
