高适应性面包酵母菌株的杂交选育

为了改善耐高糖酵母在不同含糖量面团中的发酵力,首先制备了2 4 0株耐高糖酵母单倍体,通过高麦芽糖发酵筛选培养基筛选出了2 8株麦芽糖发酵性能良好的单倍体菌株,通过测定这些单倍体在无糖面团中的发酵力,发现9株单倍体菌株的发酵力优于或等于其亲本,其中4株为a型,5株为α型。通过它们之间的杂交得到2 0 0株杂交株,在无糖、中糖、高糖面团中测定这些杂交株的发酵力,获得4株在不同含糖量(0～30 % )面团中都具有高发酵力的高适应性面包酵母杂交株。研究表明,来自同一亲本单倍体之间的杂交有可能改善面包酵母的某些特征。

Construction of Baker's Yeast with Good Leavening Activity in Lean, Regular and Sweet Doughs

To improve the leavening ability in lean dough of the sweet-tolerant strain BY-6, we selected 28 high-maltose-spore clones by high-maltose-fermentative selected medium. By measuring the gassing power in the dough, 9 spore clones with a good leavening ability in lean dough were obtained and a total of 200 hydrids were constructed by crossing them. Among these hydrids, we obtained 4 strains with good leavening ability in lean, regular and sweet dough comparable to that of strain BY-6. Especially, the gassing power of strain ZJ-1 was 20% more than that its parent from lean, regular and sweet dough. These results suggest that hydridization between spore clones derived from a single parent strain is effective for improving the properties of baker's yeast.