Sparging question

[markp]

Hi people,
Quick question about sparging, I am brewing with a grainfather and am wondering whether I should be squeezing the grain bed after the sparge water has finished dripping through or not. Have googled the question and most responses I have found relate to biab.
Have heard that by squeezing the grain to extract all the water from them can release unwanted tannins, what’s people’s thoughts ?
Thanks in advance for your replies.
Cheers
Mark

 

[wide eyed and legless]

From what I have read it is a fallacy about the tannins, but how are you going to squeeze the grain basket? I take out my grain basket and place it in a bowl and let gravity drain as much as possible, the worms will get any left over residue sugar when in the compost heap.

 

[markp]

From what I have read it is a fallacy about the tannins, but how are you going to squeeze the grain basket? I take out my grain basket and place it in a bowl and let gravity drain as much as possible, the worms will get any left over residue sugar when in the compost heap.

To squeeze the grain I push the top perforated plate of the malt pipe down to compress the grain and squeeze excess fluid out.

 

[pnorkle]

I don't bother with mine - I just let it continue to drip as the GF is heating towards boil temp. Why don't you give it a go & see how much extra liquid you get?

 

[Lyrebird_Cycles]

What strength are your final runnings?

 

[fdsaasdf]

To squeeze the grain I push the top perforated plate of the malt pipe down to compress the grain and squeeze excess fluid out.

I need to find or make a plate that can do this. I have found for beers containing oats, wheat or rye (so far) that my mash efficiency is lower than with other ingredients, and I put it down to the amount of liquid that makes contact with the grain. I am using a 56L pot as a malt basket inside an 82L pot.

I have tried no-sparging and sparging with similar results. My final runnings were 1018 last time around (last of the liquid collected from the separate pot I rested the malt basket on after removing for boil).

 

[Lyrebird_Cycles]

At almost 5 oP you aren't going to be getting a lot of leaching, so pressing won't hurt and will make up for some of the lost extract.

With a well designed brewhouse your last runnings should be about 2 oP and leaching does become a problem. I think this is due to a combination of osmotic potential and the structure of the filter bed

 

[fdsaasdf]

Yes, I think so. Thanks. I used to hit 1.010 with most brews on my old 3V setup and hit 1.012 for the first brew on my 1V setup, which was 90% ale malt 10% crystal. I don't always measure but in ~20 brews on the 1V setup I have observed that more glutenous malt bills have worse mash efficiency. I am also thinking of moving to 90 minute mashes to see if that helps (time permitting).

Also thanks for incidentally mentioning plato, as a homebrewer using a hydrometer I always think in SG, and for whatever reason I've never bothered to look before to confirm my observation that plato is roughly 1/4 of the least significant digits of the SG.

 

[Lyrebird_Cycles]

confirm my observation that plato is roughly 1/4 of the least significant digits of the SG.

It should come as no surprise to find that the "least significant digits of the SG" has a name in German: it's degrees Oechsle, so an SG of 1018 is 18 oOe. Only ever seen it used by German winemakers.

Yes, oOe/4 = oP is a good rough conversion up to about 15 oP. If you are good at mental arithmetic you can try oOe / 3.9 - oOe^2 / 5500, it's accurate to .1 oP up to any strength you are likely to encounter.

 

[markp]

Ok, so getting back on track I’m assuming it’s ok to squeeze the grain bed after sparge to get the excess fluid out ?

 

[wide eyed and legless]

Ok, so getting back on track I’m assuming it’s ok to squeeze the grain bed after sparge to get the excess fluid out ?

Yes

 

[markp]

Yes

Cheers weal

 

[MHB]

No!
Well a qualified no, lets say if the extract content of the wort isn't too low, it isn't too alkaline nor too hot - then I would say the chances of extracting tannins are pretty low.
Again in response to the OP, most of what I'm going to say is based on BIAB. If you over do the squeezing you will get quite a lot of grain fines, gelled protein and possibly glucan gels eluting (that white **** that people comment on) all of which aren't any benefit in the boil. Promotes scorching of heating surfaces, possibly interferes with the complexing of high molecular weight protein with tannins that are present in the wort and those introduced with the hops..

In truth you would have to be squeezing pretty hard, but a small batch sparge with some acidified water will get you more extract with less possible downside.
Mark