Effect of Xanthan Gum on Improvement of Bread Height and Specific Volume upon Baking with Frozen and Thawed Dough

抄録

Wheat flour was preliminarily mixed with 5% polysaccharides (locust bean gum, guar gum, xanthan gum, tamarind seed gum, native gellan gum, dextrin, LM pectin, fermented cellulose CMC, konjac glucomannan, HM pectin, κ-carrageenan, ι-carrageenan, and λ-carrageenan), and then mixed with water, salt, sugar, and yeast, followed by proofing. Next, the proofed bread dough was divided into two, frozen at −20°C for 6 d, and then thawed at 4°C for 16 h. One part of the dough was baked at 210°C for 30 min, and the other was subjected to determination of the extruded liquid from the thawed dough upon centrifugation. As the results, frozen/thawed control (wheat flour) dough presented a lower bread height (mm), lower specific volume (cm³/g), and a higher volume of exuded liquid than unfrozen dough. When polysaccharides such as guar gum, xanthan gum, and tamarind seed gum were mixed with the flour prior to making the bread dough, similar or greater bread height and specific volume than those of bread baked with unfrozen control dough were obtained. The greatest increases in bread height and specific volume on supplementation of polysaccharides were observed when xanthan gum was used. In order to clarify why xanthan gum markedly improved the breadmaking properties, oven-spring tests were conducted for 10, 15, 20, and 30 min in a 210°C oven. The breadmaking properties (bread height) of baking with frozen/thawed control dough increased until 10 min in the 210°C oven and then stopped. However, for the bread with xanthan gum, these variables did not stop increasing.