Studies On Preservation Process Of Fresh Wet Noodles

As the birthplace of noodle culture,China has the largest number of noodle consumers in the world.It is widely known that noodle is our traditional staple food.Among the various types of noodle products,the fresh wet noodles is well received by the public,as it retains the flavor and taste of the original noodles with high moisture content.At the same time,fresh wet noodle provides suitable environment for the growth and reproduction of microorganisms because of its high moisture,which makes the fresh wet noodle susceptible to corruption and not conducive to industrial production and sales.In order to solve this problem,this paper adopts a series of anti-corrosion and preservation methods for each stage of fresh wet noodle production process.The research results are divided into the following four parts.The amount of bacteria in the raw materials directly affects the microbial content of the fresh wet noodle product.So it is of great importance for the preservation of fresh wet noodles to sterilize the wheat flour and water.This paper explored the effects of different power and time of microwave treatment conditions on the sterilization effect and quality of wheat flour.The results showed that the sterilization effect of microwave on wheat flour is enhanced with the increase of microwave power and time.The content of protein and starch did not change much,the gluten index and the falling value decreased,and the water absorption and weakening degree of the dough increased.But the starch was easy to gelatinize,and the flour was easy to agglomerate if the microwave power was too high.The flour sterilization rate exceeded 90% and the flour quality had little declined at the microwave sterilization condition of 560 W for 20 s.The water retained little microorganism when it was boiled for 15 minutes.Compared with the antibacterial effect and quality of the fresh wet noodles of natural preservative chitosan and Nisin,and the chemical preservatives calcium propionate,propylene glycol and sodium diacetate(SDA),it was found that chitosan had a good inhibitory effect on bacterial mold,but it was bad for the color of the noodles and affected the sensory score.Nisin had a significant inhibitory effect on bacteria but it was not distinct on mold.Calcium propionate not only inhibited the growth of microorganisms,but also provided calcium,which was its irreplaceable advantage,but it had an adverse effect on the sensory quality such as taste and toughness of fresh wet noodles.The inhibitory effect of propylene glycol on microorganisms is higher than that of calcium propionate.And the propylene glycol can be used as a moisture retaining agent and thickener,which would improve the sensoryquality of fresh wet noodles.Among the several additives,SDA had the best inhibitory effect on microorganisms and was harmless to the human body.But the noodles would taste sour when added too much SDA.Compounded these three kinds of preservatives,sodium diacetate,propylene glycol and Nisin by orthogonal experiment.It was found that when Nisin,propylene glycol and SDA were added at 0.06%,2.0% and 0.4% respectively in the fresh wet noodle formula,it not only could play an effective role in antibacterial and fresh-keeping of noodles,but also had little adverse effect on the quality and sensory of fresh wet noodles.By observing the state of the fresh wet noodles with the different packaging conditions of vacuum degree,it was found that the vacuum degree should not exceed 0.09 Mpa when packaging the fresh wet noodles by vacuum packaging method.Spraying the noodles with 2%alcohol could significantly reduce the amount of bacteria of fresh wet noodles before packaging,and effectively inhibited the growth and reproduction of microorganisms of the fresh wet noodles during storage.Through the sterilization process at all stages of the fresh wet noodles production process,the fresh wet noodles could be safely stored for more than 50 days at 4 °C.The specific process was as follows: the wheat flour was prepared by microwave treatment under microwave power 560 W for 20 s,and the water was boiled for 15 min.Nisin,propylene glycol and SDA were added respectively 0.06%,2.0%,0.4% of flour quality.The patch was sprayed with 2% edible alcohol and then cut into strips.The noodles was packed by the vacuum packaging method with the vacuum degree of 0.085 Mpa.