ABSTRACT
Increase in proofing periods of frozen dough subjected to extended frozen storage and freeze-thaw cycles and finally a lower loaf volume is attributed to the changes in rheological properties of frozen doughs. These changes occur due to the physical damage on the gluten network caused by ice recrystallization. The major objective of this research was to reduce ice crystallization and recrystallization in frozen dough by incorporating hydrophilic gums such as carboxy methyl cellulose (CMC), gum arabic, kappa carrageenan (κ-carrageenan), and locust bean gum at three different levels with flour derived from a Hard Red Spring wheat cultivar. The doughs were stored frozen for up to 16 weeks. Bread characteristics were analyzed after day 0, day 1, and after 4, 8, 12, and 16 weeks of frozen storage for specific loaf volume, external and internal appearance, color, texture, and shelf-life. Specific loaf volume increased significantly with the addition of different levels of all the four gums compared with the frozen control. Doughs with locust bean gum had the highest loaf volume followed by doughs with gum arabic treatment. Although the external and internal characteristics of bread deteriorated with storage time, addition of gum arabic, CMC, and locust bean gum improved the characteristics compared with the control after each storage period. κ-Carrageenan gave an inferior appearance to the bread and decreased crumb quality, while locust bean gum gave the best appearance. Bread loaves made with locust bean gum had a brighter crust color and lighter crumb color as indicated by higher L color values of the chromameter. In contrast, bread made with κ-carrageenan had the lowest L values. Bread shelf-life evaluated through bread crumb moisture and bread firmness values showed that bread loaves prepared with locust bean gum retained moisture to a greater extent and were softer when compared with the frozen control. In general, locust bean gum, gum arabic, and CMC improved bread characteristics to varying degrees. Only κ-carrageenan showed a detrimental effect on the frozen dough.
