I came across this little piece purely by accident
"Mons. A. METZ made an analysis of some beer manufactured at Weisenau, near Mayence, from a mixture of 40 cwt. of malt to 8 cwt. of rice. He found that it contained of
Alcohol 3.65 per cent. } Sugar 1.63 } Dextrine 5.13 } 7.36 per cent. extract. Proteids 0.37 } Inorganic matter, including phosphoric acid 0.22 } Difference 0.01 }
Compared with an average resulting from the examination of 31 different kinds of Bavarian beer by Mons. C. Prandtl, it will be seen that the amount of alcohol is about the same; but the total amount of extract, and especially the quantity of sugar, exceeds that of any of the Bavarian kinds. Mons. C. Prandtl found in Bavarian beer—
On tbe average. Maximum. Minimum. Alcohol 3.55 per cent. 3.98 per cent. 3.23 per cent. Total Extract 6.07 6.61 5.42 Sugar 1.08 1.38 0.82
This rice beer is exceedingly clear and light: it effervesces, and has a peculiarly mild taste."
"Food Journal, Volume 3", 1873, page 209.
You learn something new every day. Like the fact that until recently Mainz was called Mayence in English. Weisenau is a suburb of Mainz. Which is odd, because Mainz is in Rheinland Pfalz. Didn't that use to be part of Bavaria? Where they were fairly strict about ingredients.
A quick check on the internet explains it. Pfalz was part of Bavaria, but Rheinland Pfalz covers a lot more territory. Including the bit where Mainz is. So it wasn't in Bavaria in the 19th century. Just very close to it.
Getting back to the rice beer, there's the same sort of description as usual: clear, light, mild. 8 cwt. out of 48 cwt. is 16.67%. Or about the same proportion a British brewer would have used of maize or rice.
By extract they mean finishing gravity. So it seems that they're saying that the rice beer had a higher finishing gravity than Bavarian beer. Quite a feat in the 19th century when Bavarian beer was rarely more than 60% attenuated. Intuitively, you'd expect the opposite.
I think this is the earliest reference I've found to German rice beer. I wonder when it was first brewed? And when will an enterprising German brewer revive it?