Viability and Performance of Pure Yeast Strains in Frozen Wheat Dough

Abstract

Freezing and subsequent storage of wheat doughs containing Saccharomyces cerevkiae, S. fructuum or Candida boidinii after undergoing a bulk fermentation step, reduced the viability of yeasts, depending on the species. Freezing and storage of doughs without bulk fermentation had no effect on viability. Gassing power was affected most by frozen storage, depending on storage time and species. Changes in acidification capability were small, and only significant for total titratable acidity. Changes in sugars and leavening were closely related. Results showed that the use of less active yeast species (S. fructuum), with high freezing tolerance in frozen dough processes would be of practical interest.

Combined effects of freezing rate, storage temperature and time on bread dough and baking properties

“…Problems associated with frozen dough include long proof time, low volume, poor texture, and variable performance (Kenny, Wehrle, Dennehy, & Arendt, 1999). Some of the poorer quality can be attributed to diminished yeast activity, the characteristics of the yeast and their survival after freezing (Baguena, Soriano, Martinezanaya, & Debarber, 1991;El-Hady, ElSamahy, Seibel, & Brummer, 1996;Hino, Takano, & Tanaka, 1987;Hsu, Hoseney, & Seib, 1979;Ribotta, Leon, & Anon, 2003;Wolt & D'Appolonia, 1984). In order to improve performance, frozen dough processors may add extra yeast, use short or no-time dough processing procedures, mix ingredients at relatively low temperatures, or incorporate new strains of freeze-tolerant yeasts.…”

“…Fluctuations in temperature have been found to be especially damaging (Berglund et al, 1991;El-Hady et al, 1996;Inoue & Bushuk, 1991). In addition, yeast may be less viable after freezing (Baguena et al, 1991).…”

Technology of Breadmaking

“…Such developments and strategies have been thoroughly reviewed by Casey and Foy ( 1995 ). In some cases the newer yeast strains have initially lower gassing rates compared to standard yeast which made them more suitable for the production of frozen dough (Hino et al 1987 ;Baguena et al 1991 ). Other approaches have included the use of trehalose-enriched yeasts, with the trehalose acting as a cryoprotective agent, and the application of dried yeasts, although successes with the latter have been somewhat variable (Spooner 1990 ;Neyreneuf and Van der Plaat 1991 ).…”

Effect of formulation on the quality of frozen bread dough

“…The effect of freezing on the yeast properties has been widely studied. Several researches showed that the yeast viability is strongly influenced by the fermentation process prior to freezing (Hino et al, 1987;Báguena et al, 1991;Salas-Mellado, 1992), by freezing and thawing velocities (Gélinas et al, 1993;Gehrke et al, 1992;Autio and Sinda, 1992;Murakami et al, 1994) and by the duration of frozen storage (Berglund and Shelton, 1993;Wang and Ponte, 1995). The yeast type and its properties also play important role in yeast viability and in the quality of the product (Gélinas et al, 1993;Murakami et al, 1994;Van Dam and Hille, 1992;Inoue et al, 1994).…”