Effect Of Carrageenan On Baking Quality Of Frozen Dough During Freeze-thaw Cycles

In this paper,frozen dough,gluten and carrageenan we re used as the object of study.The effect of carrageenan on gluten functional characteristics and baking quality of frozen dough during freeze-thaw cycles were studied by simulating the temperature fluctuation phenomenon in the cold chain transportation(Freeze-thaw cycles setting: 10 d for a freeze-thaw cycle,samples were frozen at-18 ° C and transferred to 0 ° C for 12 h at the fifth day of the freeze-thaw cycle,then back to-18 ° C).Establish a relation between the effects of carrageenan on gluten p roperties and baking quality of frozen dough,providing a theoretical basis for the application of carrageenan in frozen dough technology.The main results are as follows:1.Determination of the functional properties,water holding capacity,oil holding capacity and solubility of gluten in the process of freeze-thaw cycles.The results showed that:(1)With the freeze-thaw cycle,the water retention and solubility of gluten protein are reduced and the oil holding capacity is enhanced.The water holding capacity decreased from 136.67% at the beginning without freeze to 117.90% after the 60 days of freeze-thaw cycles.The solubility decreased from 1.97 mg / mL to 0.34 mg / mL by 31.98%.,and the oil holding capacity was increased from 1.36 g oil / g sample to 2.00 g oil / g sample at the same time.(2)The addition of carrageenan significantly slows the decrease of water holding capacity and solubility of gluten and inhibits the enhancement of oil holding capacity.After 60 days of freeze-thaw,the water hold ing capacity of the carrageenan additions of 0.01,0.02 and 0.03(carrageenan / gluten,g /g)increased by 4.22%,9.35% and 10.30% respectively compared with the blank group,and the solubility increased 30.60%,35.82% and 41.79% respectively,and the oil holding capacity decreased by 8.73%,21.87% and 29.55% respectively.2.The baking characteristics of frozen dough were determined during the freeze-thaw cycle.The results showed that the baking quality of frozen dough was significantly reduced during the freeze-thaw cycles.The specific volume of bread,color of bread core and bread interior moisture content and cohensiveness decreased with the freeze-thaw cycle,and the bread hardness,chewiness and gumminess increased.The stability of the whole dough system can be improved with the addition of carrageenan,the specific volume of bread increased,the change of the bread color was inhibited,and the decrease of the water content of the bread core was delayed,the bread hardness,chewiness and gumminess we re reduced,the pore area and porosity in the bread were increased,improving the quality of frozen dough bread..When the addition ratio of carrageenan was 0.01(carrageenan addition ratio: carrageenan / high gluten flour,g/g),the specific volume of fro zen dough bread after freeze-thaw cycles was significantly increased compared with the blank group.The changes of the specific volume of frozen dough bread were not significant with the increase of proportion of carrageenan compare with 0.01 ratio in the same period of freeze-thaw cycles.The L * value of bread core increased with the increase of the proportion of carrageenan in the same freeze-thaw cycles.The addition of 0.03 ratio of carrageenan significantly inhibited the decrease of L * value of frozen dough bread in freeze-thaw cycles.When the freeze-thaw cycles were 0-30 d,the effect of different carrageenan addition ratio on the moisture content and hardness of the bread core of the frozen dough is not significant.And the addition of 0.02 and 0.03 ratio of carrageenan had no significant effect on the moisture content and hardness of the core when the freeze-thaw cycles were extended to 60 d.The optimum ratio of carrageenan to improve the internal texture of the frozen dough bread during the freeze-thaw cycles is 0.02(carrageenan / high-gluten flour,g / g).