| The effect of almond bran on rheological and thermodynamic properties of dough, as well as the texture and materialization characteristics of noodle was studied in this paper. For the first time ,putting the almond bran and spontaneous sourdough starter into the flour to determin their comprehensive role on the sourdough noodle. Finally, the influence of almond bran on the flavor of different noodles was analyzed.With the use of farinograph and dynamic rheometer, the research was aimed at rheological properties of wheat flour-water dough containing California almond bran. In farinograph,dough water absorption rate and stability time increased while development time decreased with almond bran addition. Rheological data from dynamic rheometer indicated that , in the heating process, the effect of almond bran within 6% on the elastic modulus (G′) and viscous modulus (G″) of dough was increased , but the trend is sustained up to the 9% of almond bran and that the overlapped the value of 6%. In the cooling process, we could't find a regularity to follow. The results with frequency changing was basically accordance with the heating process. When distilled water or salted water was used in the RVA, we found that, except the pasting temperature was the basic trend of increasing(without a certain regularity), the other parameters declined with the addition of almond bran. The results of DSC indicated that the temperature was consistant with RVA and the both results may be confirmed. Enthalpy value of the samples showed a downward trend.The experimental results of measurement showed that with increasing of almond bran added, the cooking loss and the capacity of water absortion quantity increased, while the pH of noodle decreased owing to the almond bran. Noodles with addition of almond bran had lower hardness, chewiness, elasticity properties than those without almond bran. The sensory of evaluation verified the above viewpoint. Using scanning electron microscopy (SEM) method, it was found that the gluten continuous phase of treated dough appeared less tight and uniform than untreated dough, and starch granules appeared to be lossely embedded in the modified gluten network.The response surface analysis methodology of three levels and three factors was introduced to determine the influence of starter fermentation time, the amount of starter, the amount of almond bran on sourdough noodle. The results obtained showed that the fermentation time and amount of spontaneous sourdough, the amount of almond skin had a notable impact on pH, cooking loss and maximum shear force of noodle. All models for pH, cooking loss and maximum shear force demonstrated good correlation with measured data with R2 values , being 92.35%,90.02% and 95.62% respectively, indicating that they were suitable and response surface methodology could be a useful tool to predict the effects of the fermentation time and amount of spontaneous sourdough, the amount of almond skin on sourdough noodle. The ridge analysis suggested that the sourdough noodles, added with 3% almond bran ,5% spontaneous sourdough starter and fermented for 33 hours, could keep the nutritional value of almond bran and starter, and improve the characteristic of noodle.We compared volatile flavor compounds of noodles with different processes by means of SPME- GC-MS coupling technique. Gas chromatogram showed that a total of about 53 volatile flavor compounds were obtained in these samples. The amount of carboxylic acids increased in the noodle with new processing. Almond bran affected the main volatile flavor compounds in noodles and the relative content of aldehydes and enes increased.
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