BAKERS-YEAST MITOCHONDRIA, GASSING POWER AND FREEZE-THAW TOLERANCE INDOUGH

When tested in dough, six commercial baker's yeast samples showed some variation of freeze-thaw tolerance and mitochondrial protein content (P less than or equal to 0.05), an indication of their cell mitochondr ial development. However, variation of freeze-thaw tolerance was not r elated to mitochondria protein content (P less than or equal to 0.05). On the whole, yeast gas production before or after freezing as well a s after storage periods of 1 or 5 weeks at 4 degrees C was not related to its mitochondrial protein content. Some of the yeast samples were more tolerant to rapid freezing rates (9 . 2 degrees C min(-1); no sto rage in freezer) and others survived better slow freezing rates (1 deg rees C min(-1), with storage for 12 weeks at-30 degrees C). (C) 1996 A cademic Press Limited.