UEBER DEN PENTOSAN-GEHALT VERSCHIEDENER MATERIALIEN.
B. Tollens and H. Glaubitz (J. für Landwirthschaft, 1897, 97).
ON THE PENTOSANE CONSTITUENTS OF FODDER-PLANTS AND MALT.
(p. 171) (a) The authors have re-determined the yield of furfural from a large range of plant-products, using the phloroglucol method. The numbers approximate closely to those obtained by the hydrazone method. The following may be cited as typical:
| Substance | Furfural p.ct. |
| Rye (Göttingen) | 6.03 |
| Wheat (square head) | 4.75 |
| Barley (peacock) | 4.33 |
| Oats (Göttingen) | 7.72 |
| Maize (American) | 3.17 |
| Meadow hay | 11.63 |
| Bran (wheat) | 13.06 |
| Malt | 6.07 |
| Malt-sprouts | 8.56 |
| Sugar-beet (exhausted) | 14.95 |
(b) A comparison of wheat with wheat bran, &c. was made by grinding in a mortar and 'bolting' the flour through a fine silk sieve. The results showed:
| Furfural p.ct. | |
| Original wheat | 4.75 |
| Fine flour | 1.73 |
| Bran (24 p.ct. of wheat) | 11.25 |
| Wheat-bran of commerce | 13.06 |
It is evident that the pentosanes of wheat are localised in the more resistant tissues of the grain.
(c) An investigation of the products obtained in the analytical process for 'crude fibre' gave the following:
(1) In the case of brewers' grains:
| 100 grms. grains | gave furfural | = | 29.43 | pentosane |
| ——————— | ||||
| 20 " crude fibre | " | = | 2.52 | |
| Acid extract | " | = | 22.76 | |
| Alkali " | " | = | 1.20 | |
| Deficiency from | total of original grains | 2.95 | ||
| ——— | ||||
| 29.43 | ||||
(2) In the case of meadow hay:
The crude fibre (30 p.ct.) obtained retained about one fourth (23.63 p.ct.) of the total original pentosanes.
(d) An investigation of barley-malt, malt-extract or wort, and finished beer showed the following: An increase of furfuroids in the process of malting, 100 pts. barley with 7.97 of 'pentosane' yielding 82 of malt with 11.18 p.ct. 'pentosane'; confirming the observations of Cross and Bevan (Ber. 28, 2604). Of the total furfuroids of malt about 1/4 are dissolved in the mashing process. In a fermentation for lager beer it was found that about /10 of the total furfuroids of the malt finally survive in the beer; the yield of furfural being 2.92 p.ct. of the 'total solids' of the beer. In a 'Schlempe' or 'pot ale,' from a distillery using to 1 part malt 4 parts raw grain (rye), yield of furfural was 9 p.ct. of the total solids.
In a general review of the relationships of this group of plant-products it is pointed out that they are largely digested by animals, and probably have an equal 'assimilation' value to starch. They resist alcoholic fermentation, and must consequently be taken into account as constituents of beers and wines.
UEBER DAS VERHALTEN DER PENTOSANE DER SAMEN BEIM KEIMEN.[9]
A. Schöne and B. Tollens (Jour. f. Landwirthschaft, 1901, 349).
BEHAVIOUR OF PENTOSANES OF SEEDS IN GERMINATION.
The authors have investigated the germination of barley, wheat, and peas, in absence of light, and generally with exclusion of assimilating activity, to determine whether the oxidation with attendant loss of weight, which is the main chemical feature of the germination proper, affects the pentosanes of the seeds. The following are typical of the quantitative results obtained, which are stated in absolute weights, and not percentages.
| -- | Original seed | Malt or germinated product | Pentosane in | |
| A | B | A | B | |
| Barley | 500.00 | 434.88 | 39.58 | 40.38 |
| " | 500.00 | 442.26 | 40.52 | 41.17 |
| Peas | 300.00 | 286.60 | 15.25 | 15.97 |
The authors conclude generally that there is a slight absolute increase in the pentosanes, and that the pentosanes do not belong to those reserve materials which undergo destructive oxidation during germination.
In this they confirm the previously published results of De Chalmot, Cross and Bevan, and Gotze and Pfeiffer.