. The fermenting power of pure yeasts and some associated fungi . certainly result when, asin this case, the quantity of culture used as a starter is as 1 to 40 ofthe must. No. 2, which received 1 to 400 parts of culture, exceeds inactivity for the fourth day the heavy sowing of No. 3. This illustratesforcibly the point shown in all of this work, namely, that a small pro-portional inoculation with the pure culture answers every purpose, 1part to 400 being sufficient under good conditions. The validity ofthis observation is borne out hy flask No. 1, which received a compar-atively infinitesimal
. The fermenting power of pure yeasts and some associated fungi . certainly result when, asin this case, the quantity of culture used as a starter is as 1 to 40 ofthe must. No. 2, which received 1 to 400 parts of culture, exceeds inactivity for the fourth day the heavy sowing of No. 3. This illustratesforcibly the point shown in all of this work, namely, that a small pro-portional inoculation with the pure culture answers every purpose, 1part to 400 being sufficient under good conditions. The validity ofthis observation is borne out hy flask No. 1, which received a compar-atively infinitesimal sowing of 1 drop to 400 cc of must, yet, whengrowth fairly started on the third day, it rushed to a point compara-tively high on the fourth day, and reached its climax on the fifth day. The prompt control which can be obtained by a heavy sowing ofyeast when there is pressing need of securing a dominant fermentationto guard against unfavorable conditions is most amply illustrated inthis case by the prompt manner in Avhich No. 3 started. DISCUSSIOX OF TESTS. 17. Fig. 3.—Variations in rate of fermentation produced liy dififerent quantities of yeast. 18 FERMENTING POWER OF PURE YEASTS. PURE YEASTS USED SEPAEATELY AND IN MIXED CULTURES. From many comparative tests of pure yeasts sown in the samemust or fruit juice a set of 7 pure sowings and 1 mixed sowing isselected to illustrate the difference in activity which may be shownby pure and mixed easts. These tests are taken from a set of 11flasks, which were sown at the same time under identical conditionsand all kept under observation in the culture oven. The graphic recordpresented in fig. 4 includes 3 yeasts from French, 1 from German, and3 from American sources, and gives the entire range of variations de-veloped in this experiment. The flasks contained 400 cc each of filtered and sterilized apple juiceand were sown with 1 drop on a platinum loop, the mixed cultures re-ceiving 10 drops, i. e., 1 drop from each of the pure cultur
Size: 1314px × 1902px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookcentury1900, bookdecade1900, bookpublisherwashingtongpo
