Studies on fermentation : the diseases of beer, their causes, and the means of preventing them . of growthpeculiar to this ferment we should examine it during the firstfew hours of its propagation, when, under the influence of theoxygen dissolved in the fermentable liquid, its vital activity isgreatest. Later on, often on the day following the sowing,the groups become disconnected, and at the end of the fermen-tation the cells have quite separated from each other, notmore than 2 or 3 per cent, remaining united, and even thesein groups of not more than two cells together. This isrepresented in
Studies on fermentation : the diseases of beer, their causes, and the means of preventing them . of growthpeculiar to this ferment we should examine it during the firstfew hours of its propagation, when, under the influence of theoxygen dissolved in the fermentable liquid, its vital activity isgreatest. Later on, often on the day following the sowing,the groups become disconnected, and at the end of the fermen-tation the cells have quite separated from each other, notmore than 2 or 3 per cent, remaining united, and even thesein groups of not more than two cells together. This isrepresented in Fig. 39. To give an idea of the rapidity with which this fermentmultiplies, we may state that our sketch (Fig. 40) was madeunder the following conditions :—On April 28th, 1874, wecaused a flask of wort to ferment by means of a trace of high yeast. On the morning of the next day, that is STUDIES ON FERMENTATION. 189 fourteen hours afterwards, an appreciable deposit of yeast hadformed, and some frothy patches appeared on the surface ofthe liquid, showing that fermentation had set in. On May. Tig. 40. 1st we decanted the beer, substituting for it water sweetenedwith 10 per cent, of sugar. On May 2nd we decanted thesweetened water, and substituted a fresh quantity containingthe same percentage of sugar. On May 3rd, at mid-day, wetook some of the fermenting liquid from this flask and put itinto a flask of wort; five hours after the introduction of theferment we made the sketch in question. The field is coveredwith branching clusters, the groups being sketched exactly asthey occurred in the field. Their activity was due to thecondition of the ferment, and to the perfect fitness of thenutritive medium for its vegetation. In sweetened waterthe budding of the cells was considerably less active ; no branch-ing groups of cells are to be found. Budding, nevertheless,occurs to a considerable extent, but it is limited to one bud,or two at the most, to each cell. Fermentation in puresweeten
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherlondo, bookyear1879
