Study On The Stability Factors Of Processing Characteristic Of Mare’s Milk

In this paper, changes in nutrient composition of mare’s milk in different stages of lactation period were studied. The influence factors of thermal stability of mare’s milk were explored, and then the kinetic model of rheological properties of mare’s milk was constructed. The partial functional proteins in mare’s milk were also analyzed. The main results are as follows:(1)The maximum content of milk fat in mare’s colostrum could reach 3.95%. The content of protein and non-fat solids in colostrum were high in 2~24h after foaling. The content of lactose,protein, somatic cell count and total solids in mare’s milk were significantly decreased in 30~60d of lactation period, however, the change in fat was not significant. The contents of fat, lactose,protein, somatic cell count and total solids in milk period showed a fluctuation tendency. The step wise regression fitting equation of total solid in milk to protein, lactose and fat was established,Ytotal solids=-0.54708253+0.853024633Xfat+0.894024387Xprotein+1.230454825 Xlactose.(2)The effects of different temperature、p H、Ca2+、casein and chelating agent on the thermal stability of fresh mares milk were studied,using heat coagulation time method. The fitting equationestablishment of thermal stability was Y=63.13449+6.61003X1+1.37127X3-10.16386X12-8.92643X22-4.86056X32+2.75000X1X2.The optimal range of thermal processing stability were p H of 6.71~6.83,the concentration of trisodium citrate of 0.34~0.44g/L, the concentration of casein of 3.29~3.68g/L.Under this conditions,the range of HCT was 50~66s.(3)The rheological properties of fresh mare’s milk were studied with rheometer.The results indic ated that the fluid type of fresh mare’s milk was now-Newtonian pseudoplastic The fluid.dynamic model of temperature,concentration and p H to fresh mare’s milk were established.The mathematical model on the relationship between concentration and viscosity was η=K2exp(A2C).The mathematical model on the relationship between p H and viscosity was η=K3X2+K4X+K5.Establishment ofmathem atical model of the combined effects of temperature, concentration and p H value on the viscosity of fresh mare’s milk was η=[(-9E-05)X2+0.0004X+0.0015 ]2089e-1.3196Cexp(3.3787e0.1786C/RT)(4)The partial functional protein in fresh mare’s milk of different lactation period were detected by high performance liquid chromatography. The results indicated that the highest content of β-CN in 30~60d and 80~110d of lactation period could reach up to 4.362g/L,9.191g/L, respecti vely. The highest content of α-CN in 120~150d of lactation period could reached 4.673g/L.