Study Of Influences Of Acetylated Hydroxy-propyl Starch On The Fresh Wet Noodle Quality

With corn starch as raw material, mono-modified starch and native starch as a control, the effect of acetylated hydroxypropyl starch on rheological properties of dough, as well as the cooking, sensory, and texture characteristics of fresh wet noodle was studied in this paper. Based on the analyzing of rheological properties through Brabender amylograph, farinograph and extensograph and the texture properties of noodle through texture analyzer, the quality of fresh wet noodle was improved.The results of pasting properties show that with the increase of modification degree and content, gelatinization temperature of acetylated hydroxypropyl starch (AHS) declined. AHS, with mol degree of substitution (MS) and degree of substitution (DS) above0.11and0.06respectively, and concentration above10%, flour gelatinization temperature is lower than that of control. Hydroxypropyl starch (HS) with a MS higher than0.11, flour gelatinization temperature declines with the increase of HS concentration. The higher the DS and concentration of Acetylated starch (AS), the greater the gelatinization temperature increases. The peak viscosities of flour increase with the addition of AHS.The results of farinograph properties show that with the increase of AHS content in the mixture flour, the absorption ratio of the dough increases, the development time and the stability time of the dough shorten, the weakness of the dough increases, the evaluation value of the dough drops, which leads to a poor quality of the dough performance; The results of extensograph properties show that the stretch resistance, stretch energy, and extensibility of the dough increase firstly then decline. With the percentage of AHS10%in the mixed dough, the fresh wet noodle has optimum rheological properties. With regard to improvement on rheological properties of dough HS is inferior to that of dual-modification starch. The AS and native corn starch bring negative impact on dough rheological properties.The results of cooking properties show that with the addition of AHS, the cooking time of noodle shortens, the capacity of water adsorption increases, broken rate and cooking loss raise with it. Compared with that of dual-modification starch, mono-modified starch has a long cooking time and there is no significant difference in other aspects.The results of sensory properties show that with the addition of AHS, the color, appearance, and viscosity of noodle improve greatly. The greater the modification degree of ASH, the better the sensory quality of noodles is. When the degree of modification was MS0.11, DS0.06, sensory properties of mixed flours was higher than that of control.The results of texture properties show that as the increase of modification of AHS, the hardness, gumminess, chewiness, shear properties of noodle raise accordingly. Compared with mono-modified and native starch, the influence of dual-modification starch was obvious. When the degree of modification was MS0.11, DS0.03, the hardness, gumminess, chewiness are higher than those of control. When the degree of modification was MS0.11, DS0.09, the shear properties of noodle is better than that of control.The results of improvement on the quality of fresh wet noodle show that the optimal formula of improver was as follows:monoglyceride2.5%, wheat gluten1.5%, salt1%. The broken rate and cooking loss of fresh wet noodle decreased, the quality of it was improved under the above condition.