Microscope in the brewery and malt-house / by Chas. Geo. Matthews and Francis Edw. Lott.

  • Matthews, Chas. Geo. (Charles George)
Date:
1889
Catalogue details

Licence: Public Domain Mark

Credit: Microscope in the brewery and malt-house / by Chas. Geo. Matthews and Francis Edw. Lott. Source: Wellcome Collection.

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    yeast is produced to set a much larger fermentation, and so eventually enough is obtained to pitch a square. For further detail we must refer our readers to Hansen’s own communications,# or translations and abstracts of them in the Brewing Journals. Hansen adopted at a certain stage in his experiments, a solid medium for the initial cultivation of the selected cells, consisting of a mixture of hopped wort and gelatine. It was thus made possible to trace the development of the single cells under the microscope. The method is as follows :— A specimen of the yeast is largely diluted with water in a Chamberland flask ; drops of this are further diluted with hopped wort and gelatine—wort of Sp. gr. 1058, and 5—10% of gelatine, filtered bright, or fined and filtered— Fig. 22. b Bottcher Chamber. contained in test-tubes in which it has been sterilized and cooled to 70—750 F. Complete mixture is effected, and a drop of the gelatine wort, now containing yeast, is examined microscopically, and should show only a cell or two to a field. Dilution to any desired extent may now be carried out; a drop being finally withdrawn by a sterilized glass rod, and spread on the under surface of a thin cover-glass, which is placed on the ring of a Bottcher or Ranvier moist chamber.f [Figs. 22 and 23.] The Bottcher chamber [Fig. 22] consists of a glass cell formed by cementing a ring (c) to a slide ; water is placed in the bottom (,d), and the position of the drop of gelatine is at b, on the under side of the cover-glass a. The * Untersuchungen aus der Praxis der Gahrungsindustrie.—Dr. Emil Chr. Hansen, t These moist chambers appear to us to be a modification of Van Tieghem and Lemonnier’s cell for examination of moulds. Compare “Etudes sur la Biere,” Pasteur, p. 153 ; trans. p. 155.
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