Research On Exploitation Of Salt-Free Frozen Cooked Noodles Based On Sanxan And Quality Improvement

The impact of high-salt diet on human health is getting more and more widespread attention.In the background of fast-paced life and high nutritional requirements,frozen cooked noodles came into being.Under the advocacy of national salt reduction strategy,the development of salt-free frozen cooked noodles has good foresight.However,the lack of sodium chloride in frozen cooked noodles will negatively affect their quality,so how to solve this problem is the industrialized production of salt-free frozen cooked noodles Therefore,how to solve this problem is the key to industrial production of salt-free frozen cooked noodles.In this study,the best hydrocolloid for freezing and thawing of salt-free frozen cooked noodles was selected,and how this hydrocolloid acts on salt-free frozen cooked noodles and its mechanism of action were further investigated to develop high-quality salt-free frozen cooked noodles.Firstly,the effects of four hydrocolloids(xanthan gum,guar gum,curdlan and sanxan)on the quality(firmness,chewiness and toughness)of salt-free frozen cooked noodles were investigated,and the results showed that the optimal additions of the four gums were 1.2%,0.9%,0.9% and 1.2%,respectively,and the sanxan was more effective in reducing the quality deterioration during freeze-thawing.The effect of the addition of sanxan on the textural and tensile properties of the frozen cooked noodles was further investigated by using a physical property analyzer,and it was found that the hardness,elasticity,maximum tensile force and maximum tensile distance tended to increase and then decrease with the increase of the addition amount,and the maximum at the addition amount of 1.2%,and there was less adhesion.The results showed that the L* value gradually decreased and ΔE* value increased during freezing and thawing,and the addition of sanxan reduced the decrease of L* value(3.33%,90.99 to 87.96)and the increase of ΔE*(33.48%,9.02 to 12.04)to 0.96%(90.58 to89.71)and 9.23%(9.43 to 10.30),respectively.The determination of thermal stability of saltfree frozen cooked noodles by thermogravimetric analyzer showed that the addition of sanxan enhanced the thermal stability of the noodles.The laser confocal scanning microscope photographs showed that the addition of sanxan caused the starch granules to be well wrapped by the protein network,and the sanxan inhibited the damage of the gluten network by ice crystals during freeze-thawing.Secondly,protein molecular weight and subunit distribution were determined by SDSpolyacrylamide gel electrophoresis and reverse chromatography,and it was found that the molecular weight bands of the samples were deepened under the addition of non-reducing conditions and there was no significant difference under the reducing conditions,and the total wheat gluten protein content was less and the total alcoholic protein content was more than that of the control group under the effect of sanxan.Sanxan inhibited the breakage of S-S and The ionic bonding was weak in the salt-free frozen cooked noodles,and the hydrogen bonding and hydrophobic interactions were strong,and the addition of sanxan had a greater effect on the ionic bonding and could reduce the exposure of hydrophobic sites,presenting a lower surface hydrophobicity.Again,a study was carried out on the sanxan-gluten protein hybrid system.The hardness of gluten protein tended to increase,adhesion increased,and chewiness and elasticity decreased during freeze-thawing process,and the addition of sanxan decreased the hardness,elasticity and chewiness but had higher adhesion under the same freeze-thawing cycle.SEM results showed that the pores of gluten network increased during freeze-thawing process,and the gluten protein structure was looser and less tight with the addition of trizan gum.SDS-PAGE patterns and molecular exclusion results showed that SDS-PAGE and molecular exclusion results showed that the protein SDS extraction rate increased during freeze-thawing,the peak area of the samples increased with the addition of sanxan,and the soluble protein increased.The increase in hydrophobicity of gluten protein surface was much larger than that of the control group.The addition of sanxan exposed the charged amino acids of the protein with more charge,and the increase in zeta potential during freeze-thawing was higher than that of the control group.Finally,the effect of sanxan on the state of water presence and properties of salt-free frozen cooked noodles was investigated.The freezable water content of salt-free cooked noodles was measured by DSC,and the freezable water content increased gradually during the freeze-thaw process.The addition of sanxan increased the proportion of strongly bound water,reduced the free water content and inhibited the water migration rate.The size of gluten protein pores reflected the volume of ice crystals,and the volume of ice crystals increased during freezing and thawing,and the pores increased.The total volume of ice crystals on the frozen cooked noodles with the addition of sanxan was reduced,and the number of large pores and tortuosity were reduced.This study provides new ideas and methods for the development of salt-free cooked frozen noodles,and further expands the application of sanxan in food products,especially frozen noodles.