Any UK brewers here??

[Northern_Brewer]

The efficiency has gone through the roof. I mean its like 90% efficiency according to my software. I did not think that was possible. The trouble is I am overshooting my targets by at least 10 gravity points. The upshot of this is that my beers are finishing with a higher gravity than I want. I am not sure if its the malt or the yeast or my instrumentation. It could be that since I have been doing low oxygen brewing that the yeast have not had enough oxygen, I don't know.

You need to split the problem. The obvious thing to do is to calibrate your kit, as that's easy to do with plain water and a 10% sugar solution (dissolve 10g table sugar in a bit of water and make it up to 100ml = 10 Plato = 1.040) - there's been plenty of threads on how to do it (or eg BYO).

Don't forget gravity readings should be either taken at 20C or adjusted for temperature!

When you say "90% efficiency" I assume you mean brewhouse efficiency, so eg 4kg of Maris Otter is making 19 litres of 1.060 wort? That's commercial levels of efficiency, so the eyebrows do rise a bit at that and it might hint at a measurement problem - although one certainly hears of Grainfather-type systems getting into the high 80s so not completely impossible.

Or are you talking about attenuation being 90%? As in 1.050 goes down to 1.005?

Or when you say "overshooting my targets by at least 10 gravity points" are you saying that you're aiming for 1.010 and getting 1.020? So a much lower attenuation than expected? Yes that could be a stall due to low oxygen - easy enough to test, just take a sample out and aerate it thoroughly, then see how its FG compares.

 

[MSK_Chess]

My last batch used 3.5KG's of pale malt, 350g of torrified wheat, 150g of crystal malt, 70g of acid malt and 300g of invertsugar. I just wanted to make something, light, dry, creamy and hoppy. It was supposed to finish at 1045 and ended up at 1055. I had my efficiency setting at 75% on my software but its more than that, way more. I should say that the finished gravity is around 1020 when I expected it to be 1010 from 1045. The thing is the beer is not overtly sweet.

Thank you so much for these excellent suggestion I must solve this and will apply them diligently.

 

[Northern_Brewer]

Well Brewer's Friend reckons that 19 litres of 1.055 from that grist represents 73% brewhouse efficiency so it looks like the mash has worked "normally", even if your forecast was out. You might want to check the calibration of your volumes, and that your software is set up correctly - or is it just allowing for the pale malt and not the other components of the grist? The 3.5kg alone would get you near 19l of 1.045 at 75% efficency.

1.045 to 1.010 is 77% attenuation which is reasonably high (WLP007 is quoted at 70-80% on the WL spec), 1.055 to 1.020 is 63% attenuation. So yes, it looks like you have a fermentation problem - oxygen could be limiting, I'd also look at the health of the yeast you're pitching, and how much you're pitching.

 

[MSK_Chess]

Ok I understand. Yeast was healthy, made a starter from a fresh pack of WLP007, best before date was like March 2018, roughly about a litre, smelled and looked excellent, took off excellently. Checked the calibration of my refractometer last night after your suggestion, was pretty close to 1040, 10 BRIX. Yes it does sound like an oxygen problem being as you say a limiting factor. Will draw about a 500ml aerate it and see if i can get the OG down. Thanks so much Northern Brewer its really helpful.

 

[MSK_Chess]

I must report that the problem was my refractometer, I bought a new hydrometer and the final gravity was 1014, beer is excellent, dry and bitter. Invert has thinned the body excellently and it has a creamy fluffy head due to the wheat. I would say it was a success.

 

[stz]

When you get some experience you start to see structure within what previously appeared chaotic. Most maltsters produce a typical range with a few speciality grains unique to them though most of the more common and popular ones are copied and an own version is produced which may or may not have a different name depending on trademark/branding.

You just need to break it down to base malt by colour. Flaked adjunct. Crystal. Dark. Toasted. Roasted. Smoked. A lot are interchangeable depending on local market and availability and you have to kind of know what the goals are and the aim of the brewer in order to know which ones are optional and which are essential to the finished beers character. Minor differences in SRM/EBC result in minor colour differences, but big differences should be accommodated for up to and including a change of malt variety if deemed necessary. Compounding this are differences in seasonal variation/spec from batch to batch. 9/10 when we see a home brew recipe with a convoluted grist we simplify it, tweaking some things up or down to get an approximation. Actually going to the hassle of using brown malt (especially when you buy by the ton!) is very rare, but we will if it makes a beer.

The biggest irritation is they blend malt to bring the numbers into typical ranges on the spec sheets, but while the numbers are the same, the beer isn't the same. We use a lot of crisp best ale malt and I swear it is just a blend with a wider tolerance than their more premium offerings. We blend it back with extra pale (exactly the same as their lager malt with wider tolerance) when it turns up looking particularly dark and malty.

A lot of british base malt throws a sweet/toffee/caramel/malty character when used in beers above 5.5% which I swear is the reason why so many american home brewers seem to love putting crystal in our pales (we aren't putting crystal in our pales and crystal doesn't taste like that!). We blend extra pale/lager/pilsner malt back with it to reduce this british character in bigger modern IPA. On the subject of crystal you will get more mileage out of light crystal than dark. Dark crystal is very potent and dominating and I'm hesitant to use more than 2% where as light crystal is grand all the way up to 8-10%.

I'm fond of the phrase you might have the recipe and even the yeast, but you haven't got the beer because you haven't got the plant and process. As a result you can't get too hung up on 'exact' clones, you just set out with the same intent to produce the best version of something you can and enjoy owning it.