efficiency

[400d]

I believe I have bad grains, that are not fully modified. Though, when I cut open one grain, there is a white powdery thing inside, all the way to the husk, it seems so full of sugar.

Undermodified malt is the most likely answer. I know some French maltsters still do (deliberately) supply undermodified malt. If that is the case you will have to do a full decoction mash - not a temperature-stepped mash, that's not the same thing.

A decoction mash is for undermodified malt and entails boiling portions of the mash to gelatinise the starch. It is quite complicated.

A temperarture-stepped mash is for high-protein malt (which undermodified malt will also be). Decoction automatically temperature-steps the mash anyway.

It would be a good idea to find out something about the malt, or whether or not the local brewers you mention do a full decoction. That would give a clue.

I wrote to the best local brewery (they produce fantastic beer) and asked them if they know for the malt factory where I bought my malt. I was very surprised with the answer.

They wrote that they use the same malt that I have from the same factory. Unfortunately, they said that they can not explain how they mash, because of their business policy.....

[adm]

I crush very fine. I stir vigorously. I batch sparge twice. I squeeze the hell out of the bag at the end.

And I hit 42%

The more I read this thread, the more convinced I am becoming that the malt is under modified compared to british/american malt. Even brewing ina bag, you should be able to get better than 42%.

CALL THE MALTSTER and ask them for a malt analysis sheet, then post it here so we can have a look and see. Also ask them whether the malt they supplied is suitable for a single step infusion mash or do they recommend a step or decoction mash. You said it comes from Eastern Europe and I would have thought that the brewers there are more likely to do a more complex mash, so the malt may be tailored to their processes and less modified.

I bet that's the issue. The grain isn't bad, but it's probably not produced specifically for UK ale types...... a stepped mash may well sort your problem out.

(EDIT - See Graham's reply above.....decotion not step mash)

[Graham]

a stepped mash may well sort your problem out.
(EDIT - See Graham's reply above.....decotion not step mash)

A temperature stepped mash might be fine; I think it depends upon how much undermodified the malt is. Undermodified malt has a proportion of unmodified starch in it. This starch has to be gelatinised before the mash enzymes can get at it. As it happens the gelatinisation temperature of malt starch is about 65°C, but at that temperature certain other enzymes that are necessary to break down the starch further have been destroyed, and also the enzymes that breakdown the excessive protein have been destroyed.

If a malt is only a little undermodified a temperature-stepped mash will probably suffice, but if it is a lot undermodified a decoction is probably called for.

400d could try taking a grain of malt and biting first one end, then the other. If one end is soft and the other hard, you have partly-modified malt. You could try cutting a grain in half lengthwise. If one end looks glassy, steely, compared to the other, then again you have partly-modified malt.

I think that you may already have looked at your malt in that way though, so perhaps I am barking up the wrong tree.

[400d]

a stepped mash may well sort your problem out.
(EDIT - See Graham's reply above.....decotion not step mash)

A temperature stepped mash might be fine; I think it depends upon how much undermodified the malt is. Undermodified malt has a proportion of unmodified starch in it. This starch has to be gelatinised before the mash enzymes can get at it. As it happens the gelatinisation temperature of malt starch is about 65°C, but at that temperature certain other enzymes that are necessary to break down the starch further have been destroyed, and also the enzymes that breakdown the excessive protein have been destroyed.

If a malt is only a little undermodified a temperature-stepped mash will probably suffice, but if it is a lot undermodified a decoction is probably called for.

400d could try taking a grain of malt and biting first one end, then the other. If one end is soft and the other hard, you have partly-modified malt. You could try cutting a grain in half lengthwise. If one end looks glassy, steely, compared to the other, then again you have partly-modified malt.

I think that you may already have looked at your malt in that way though, so perhaps I am barking up the wrong tree.

this is how they look inside. I tried to bite them, but I really can't evaluate which part of it is softer or harder - they are just too tiny, and they just crack completely no matter where I bite...

[400d]

You did buy crushed malt didn't you ?

no I'm crushing it myself

[400d]

OK. That would have explained the poor conversion. It still may explain it depending on the how good the crush is.

50% efficiency for no sparge brewing isn't unreasonable so a poor crush when brewing in a curtain may well yield 42%.

if you want I can post the picture of my crush. I believe it is very good.

[400d]

this is my crush

[Graham]

That grain looks fully modified to me - I can't see any difference in colour between one end and the other. It seems as if your problem is elsewhere.

There is a line drawing on how modification proceeds here: http://www.mosquitobytes.com/Den/Beer/H ... /Malt.html. Underneath the drawing there is mention of the "sinker test" for undermodified malt.

However, it now looks as if your problem is down to your mash. Might be a good idea to do an iodine starch test at the end of your next mash, although I am not sure exactly what that will tell us.

[400d]

That grain looks fully modified to me - I can't see any difference in colour between one end and the other. It seems as if your problem is elsewhere.

There is a line drawing on how modification proceeds here: http://www.mosquitobytes.com/Den/Beer/H ... /Malt.html. Underneath the drawing there is mention of the "sinker test" for undermodified malt.

However, it now looks as if your problem is down to your mash. Might be a good idea to do an iodine starch test at the end of your next mash, although I am not sure exactly what that will tell us.

I did iodine test every time by now. If I take some mash water after 5 minutes of mash and mix it with iodine it turns black. after 60 minutes of mash, no reaction at all....