Effects Of Lipids On Dough Properties And Noodle Quality

For this paper, we extracted the free lipids form wheat flour Firstly, then added the freelipids, vegetable oil(wheat germ oil and peanut oil) and animal fat(lard) into flour by differentratio, then analysised the effect of different oils on gluten properties, pasting properties,farinograph properties and noodle quality. While used wheat germ oil as material, increasedthe degree of saturation by hydrogenation modification, obtained a series of different oils,added the oils into wheat flour, test the characteristics of dough and noodles. The resultsshowed that:1. The content of wet gluten decreased with the increase of oil content in flour whichadded oil; the sedimentation value of flour was not impacted by the free lipids, wheat germ oiland peanut oil, but animal fat increased the sedimentation value significantly; The waterabsorption of dough was decreased with the increase of oil content; dough formation time andstability time was delayed by three kinds of vegetable, not impacted by lard; the peakviscosity of flour was decreased with the increase of oil content.2. With the increasing of oil content, the hardness and adhesiveness of noodles decreased;the hardness of cooked noodles was increased with the increase of oil content, elasticity ofnoodles was not changed. The extension distance of noodle was higher than the original flournoodle, and the higher the oil content, the longer the extension distance, but cooked noodleschanged not rule. The water absorption rate of noodle, loss rate of dry matter and loss rate ofprotein was changed complex.3. Oils had little effect on gluten yield, though sedimentation value and gluten index hasa rising trend; the stable time of the dough was effected by oil saturation, which adding theiodine value about115of hydrogenated oil, the dough stability time was the longest, andwhich adding value about80of hydrogenated oil, the dough stability time was the shortest;adding wheat germ oil can increased peak viscosity, decreased the flour setback value.4.The increased of oil saturation reduced the hardness of recombination flour noodles,though elastic effected not significantly, the recombinant flour with highest saturation oil hasthe worst cohesiveness, the trend of noodle recovery was similar; the hardness of cooked noodle increased with the increase of oil saturation, while the other three TPA indexes getworse; the power of tensile was biggest when the oil iodine value around87, but the tensiledistance was not changed; the tensile strength and breaking length is the best with the oiliodine value around87.5. Added the different saturation oil into the flour, then extraction the free lipids form theflour and noodle, found the extraction rate was smaller in liquid lipids than solid fat.6. When the oil iodine value around115, added this oil could prove dough properties, thestarch granules in the exposed area of the gluten decreased and the structure of gluten wasmore uniform and closer, when the oil iodine value around80, the structure of gluten gotworse; the structure of noodle was best when the added oil iodine value around115and100,the structure of gluten was closer and uniform.