Expert: Ed Westemeier - 12/28/2009

Question
QUESTION: Dear Ed,

I wanted to know what is the average percentage of malt that can be produced from a ton of barley.

Regards,
Divya

ANSWER: This depends on the specific malting technique used, but in general, you can say that there will be approximately the same amount of malted barley at the end of the malting process.
There is a very small loss of material during the process (for example, some carbohydrates are lost after being dissolved in the steeping water, and the rootlets are lost after the kilning step), but there is also some water weight gained during the process. Overall, these gains and losses amount to only a few percent, so in general you can ignore the effects if you are only interested in total quantity.

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QUESTION: Dear Ed,

Thanks for the reply.

So in general it is safe to say that 1 ton of barley would produce 1 ton of malt and out of this approximately 65% would be maltose.

Regards,
Divya  

Answer
No. Free maltose is rarely found in malt, since it is converted to glucose by maltase. You would expect a typical malt sample to contain something on the order of 58% starch, 10% sugars, 10% proteins, and various other components. But that only applies to base malts, not specialty malts.
Malting is a complicated and specialized field, and general numbers like this are too simplified to be very useful.