Very poor extract efficiency.

[Top Cat]

I’m scratching my head here!
I’ve not long brewed the Leffe Blonde kit from the MaltMiller, I posted on recommendations on the water treatment in the appropriate section.
Having followed the mash instructions, I batch sparged as usual in two stages, I always check the gravity before draining into the boiler at both stages, and, compared to the volume of grain I used, the hydrometer readings were much lower than expected.
I carried on with the boil, adding the candy sugar last ten minutes, I should have reduced the amount of hops due to the weaker wort, but didn’t!

When the wort had cooled to 20c a hydrometer reading was taken and I got a reading of 1053 OG.
The OG quoted on the recipe was 1065 ( If necessary see the MaltMiller recipe on my water treatment post)
I’m no mathematician but I normally get around 70%-75% efficiency with the way I mash and sparge and I’m perfectly happy with that, not around 50% with this one!
Any ideas what could have caused this?

[Eric]

The syrup is likely a third water and two thirds sugar, and added to the boiler would provide 120 litre degrees adding 5 points to gravity if we assume one litre of wort was lost or left behind in the boiler or FV.

So before that you would need to have 23 litres at 1060 from the grain, which ignoring losses would be 1380 litre degrees.

Without any losses you might get 300 litre degrees from a Kg of Pilsner Malt, while aromatic and wheat malt would give 280 litre degrees per kg, totaling 1627 litre degrees, which would be 85% extraction. That is a tough call unless the weights supplied were a bit liberal.

[Top Cat]

I’m glad you mentioned the candy sugar Eric, I gave it nine points not knowing the difference between solid sugar and liquid, it’s obviously less.
The mash itself seemed to go fine. I roughly followed your guidelines and a call from the MaltMiller on the water treatment, the mash ph was a little high at 5.5.
I generally, with approximately 100g of leaf hops in the boil, have to include 2 more litres for boiler wastage to get a desired finish amount.
I assume MaltMiller don’t take this into account, their measures are always precise and there’s no way I get an efficiency of 85%.
I think I’m going to put this down to experience!

[Eric]

I'd take the water aspect out of the equation. Yes, better water treatment will achieve greater efficiency, but the difference isn't massive on a homebrew scale. Belief that a particular pH in the mash is the be all and end all of water treatment is a long way from reality, yes it is vital, but it is still possible to get pH right and the beer wrong.

I'm sure the beer will be drinkable.