Preliminary Study On Lyophilizing Previously Fermented Juice

The mechanism of Previously Fermented Juice (PFJ) , freezing out PFJ and adding freezing powder silage have been made using alfalfa in this laboratory scale experiments. In experiment 1 , the effects of different fermented time (24h ,48h ,72h) , adding sucrose at rate of 40gL-1, 20gL-1, 10gL-1 and adding different multiple water on Previously Fermented Juice (PFJ) quality were studied . The lactic acid bacteria number and pH of PFJ showed that adding 2 multiple water > 20g L-1 and fermented 48h are the best combination.In experiment 2nd, we chose compound pretectants made of seven kinds of pretectants. The results showed that : (1)The seven pretectants was as follows :Voglycerin>lactose>milk power without fat>L-cys>sucrose>glucose; The effect of Vc and sugar were distinct; (2) The optimal freeze-dried compound pretectants formula was as follows: glycerin 40mlml-1,Vc20gml-1, lactose 20gml-1, milk power without fat 100gml-1,L-cys 10gml-1, sucrose 50gml-1, glucose 100gml-1.In the 3rd experiment, It was carried out using fourth growth of alfalfa harvested just before the flowering stage , the harvested alfalfa was cut with a disintegrator into 2~4cm after and treated before ensiling with 20ml freezing powder, PFJ, pretectants and lactose, they were preserved for 48 days. Results from this experiment showed the addition of freezing powder was effective in improving the silage quality by increasing lactic acid content, depressing the formations of acetic acid, butyric acid and ammonia, and marked lowering the pH value. At the same time the silage quality got best during the four treatments.