Abstract:

The effects of ultrahigh pressure (UHP) and nisin treatments on microbiologcial quality and color of low-temperature sausage was investigated by single-factor method. Subsequently, an orthogonal array design involving 9 experiments of nisin concentration, pressure and pressure-holding time at three levels was employed for maximizing weighed score of total colony number (50%) and L*- (25%) and c*- (25%) values of sausage. The L*-value increased, while the a*-value and the b*-value decreased with the increase of pressure and the prolongation of pressure-holding time. The combined treatment of UHT and nisin presented higher sterilization effect than the single treatment. The optimal conditions for the combined treatment of UHT and nisin were determined as follows: nisin concentration 0.02%, pressure 400 MPa and pressure-holding time 10 min. The results showed that the combined treatment of UHT and nisin not only has a good sterilization effect, can increase the L*-value of sausage as well.

Key words: sausage, nisin, ultra high pressure, total colony number, color