Characterization of a Torulaspora delbrueckii diploid strain with optimized performance in sweet and frozen sweet dough
- 作者：Maria José ; Herná ; ndez-Ló ; pez ; Claudia Pallotti ; Pasqual Andreu ; Jaime Aguilera ; José ; Antonio Prieto ; Francisca R ; ez-Gil
- 关键词：Torulaspora delbrueckii ; Baker's yeast ; Frozen dough ; Freezing ; Stress
- 刊名：International Journal of Food Microbiology
- 出版年：2007
- 期刊代码：63_01681605
- 类别：abs
- 出版时间：1 May 2007
- 卷：116
- 期：1
- 页码：103-110
- 文件大小：315 K
摘要
Torulaspora delbrueckii is a baker's yeast that is highly tolerant to freeze–thaw stress, making it suitable for frozen dough technology. The T. delbrueckii strain PYCC5321, isolated from traditional bread dough, combines this tolerance with a high degree of ionic and osmotic stress resistance. However, the industrial use of this strain for frozen and sweet frozen baking is hampered by its small cell size, which causes clogging problems at the filtering stage. Here, we report the construction of a stable diploid strain of T. delbrueckii PYCC5321, which we named Td21-2n. The new strain was more than 2.7-fold bigger than their haploid counterpart, whereas biomass yield, stress resistance and sweet dough leavening ability were found to be similar in both strains. Moreover, the gassing power of the diploid after dough freezing also remained unaltered. Thus, Td21-2n meets the requirements necessary for industrial production and is suitable for application in frozen sweet baking products.