fermentation was 330 minutes。Sensory analysis of mulberry yogurt showes that   we

can get the highest score of 86。15 points when i added 0。5% mulberry yogurt。The color and texture in mulberry leaves supplementation between 0% and 1。5% of mulberry yogurt has no significant difference (p<0。05) with LSD multiple comparison method。 In terms of flavor, the two groups were significantly different (p>0。05), and got the higer score。

Put  the  formed  mulberry  yogurt  under  the  condition  of  4℃ for  21      days

continuously。 The pH, titratable acidity, water retention, viscosity and other physical properties were detected in the first,seveth,First, seventh, fourteenth, twenty-first day Separately。each concentration of mulberry leaves in the yogurt of Streptococcus thermophilus and Lactobacillus bulgaricus were counted with the M17 and MRS medium respectively。The results showed that the number of Lactobacillus bulgaricus in yogurt of adding mulberry leaf powder’s amount of 0%, 0。5%, 1。5%, 2。5% is from the first day of the 6。63×108, 4。77×108, 2。83×108, 1。98×108  dropped to eighteenth

days   of   6。20×108,   4。27×108,   2。76×108,   1。78×108。   Streptococcus    thermophilus

decreased  from  the  first  day  of  the  5。40×108,  2。98×108,  2。22×108,  1。80×108        to

5。23×108, 2。97×108, 1。23×108。 The pH from the first day of the 4。48, 4。50, 4。48, 4。58 was dropped to twenty-first days 4。16, 4。13, 4。12, 4。10; the water retention rate from the  first day  of the  82。1%, 80。5%, 78。3%, 72。4% was dropped to twenty-first     days

74。6%, 71。3%,  69。4%  and  63。4%;  the  viscosity  increased  from  1198,  m。Pa。s 982

m。Pa。s, 936 m。Pa。s, 926 m。Pa。s to 1355 m。Pa。s, 1164 m。Pa。s, 996 m。Pa。s and 962 m。Pa。s。

Through the Determination of total polyphenol in mulberry yogurt,The results show that, with the increase of concentration of mulberry leaves, the capacity of mulberry leaf yoghurt total antioxidant and the contents of total phenolic matter were increased,   the   mulberry   yogurt   concentration  was   0%,  0。5%,  1。5%  and  2。5%,

corresponding to the total phenolic content was 0。011, 0。072, 0。035, 0。127 mg/mL。 Determination of the mulberry leaf yoghurt DPPH free radicals clearance ability and alpha glucosidase inhibition, results show that, the more mulberry leaf powder was adding amount the yogurt, the mulberry leaf yoghurt DPPH free radical was scavenging ability and alpha glucosidase inhibition was also more and more high。 Then using the SPSS software to detect mulberry yogurt concentration corresponding to   0%,   0。5%,   1。5%   and   2。5%  of   the   DPPH   free   radical   scavenging ability

corresponding  EC50  values were 0。330 mg/mL, 0。310 mg/mL,  0。302 mg/mL,    0。302

mg/m; of α-glucosidase inhibition IC50 values were 13。18, 9。578, 6。309, 433。2, 2。443 mg / ml;Found that the more mulberry leaf powder adding in yogurt, the DPPH free radical scavenging ability and α-glucosidase inhibition is also more and more high, so it is inferred that mulberry yogurt is a certain hypoglycemic effect of antioxidant function of yogurt。

Keywords: mulberry、yogurt、polyphenol; antioxidant activity、α- glucosidase inhibition