![]() of water and 3.5 grams of hops for 48 hours. (2) By digesting 0.5 grams of the same malt with 100 c.c. (1) By digesting 0.5 grams of finely divided malt with 100 c.c. This is shown by the following experiment :. In the first place we found that an aqueous infusion of hop extracts less diastase from a given quantity of malt than does distilled water under similar conditions. As we know that hops contain a considerable amount of tannin, and that tannin has a very great retarding influence on diastatic action, owing to its rendering insoluble that class of albuminoids to which diastase belongs, it seemed highly probable that the tannin of the hop was responsible for the abnormal results obtained with the aqueous infusion. It therefOre seemed in the highest degree probable that there was something extracting from the hop which prevented the diastase going into solution. We have already referred to the difficulty there is in extracting enzymes from some kinds of tissue, owing to the tenacity with which they are retained by the cell protoplasm, but it is very seldom indeed that an aqueous extract of such tissue, when properly prepared, is entirely without action, as is the case with the hop infusion. The seeds doubtless contribute largely to the diastatic activity of hops, but the bracts of the strobiles, which are really leaf organs, have also a very marked hydrolytic effect, yet an aqueous infusion of the same hops, no matter how concentrated it maybe, is incapable of producing any diastatic in fluence. (3) Foliage leaves of hop plant, 2.01 grams maltose. (2) Hop-cones, freed from seed, 2.06 grams maltose. (1) Hop-cones, including' seeds, 9.60 grams maltose. The results are calculated out for the amount of maltose produced from soluble starch by 10 grams of the material acting under standard conditions :. We also append a determination of the diastatic activity of the foliage leaves of the hop plant. As it seemed possible that the diastatic activity of hops might be due wholly or in part to the seed: which they generally contain, we have made comparative experiments with the hop strobiles, in one case including the seeds, and in the other after the seeds had been carefully picked out. "It must be remembered, in considering the results of this last experiment, that the influence of the yeast of the beer had been completely prevented by the chloroform, and that if the yeast had been still in possession of its functions, hydrolysis would have proceeded with even greater rapidity, as we know very well that under the combined action of organised ferments and diastase hydrolysis often goes on much more rapidly than under the influence of the diastase alone. Partly because it's Easter and I've got better things to do. Partly because I'm not sure that I really understand it all. There isn't going to be much commentary from me this time. Something only of interest to a few professional brewers. I thought that the article I've based these posts on was intrguing, but rather obscure. I'm continually amazed at what grabs my readers' attention and what doesn't.
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