Effects of ultra high pressure on the properties of pork meat gels containing agar

Polysaccharide can be used as fat substitutes to develop low-fat meat products. Therefore, the modification of low-fat meat gels was carried out through ultra high pressure. Effects of ultra high pressure on properties of pork meat gels containing 0.4% agar (PMGA) were investigated in the range of pressure from 100 MPa to 600 MPa, pressure holding time from 10 min to 40 min and medium temperature from 10℃ to 40℃ via single-factor experiment. Water-binding capacity (WBC), color and hardness of pressurized PMGA were evaluated. The results showed that cooking loss (CL) of the PMGA decreased significantly at 200～400 MPa（p＜0.05), comparing with unpressurized PMGA. Water-holding capacity of the PMGA increased to some extent at various levels of pressure and color index b*-value decreased obviously with an elevated pressure from 100 MPa to 600 MPa (p＜0.05). Lighteness L*-value of the PMGA increased evidently and color index a*-value decreased significantly in the range of 400～600 MPa (p＜0.05). Ultra high pressure induced a significant increase in hardness of the PMGA at 100～400 MPa, but an obvious decrease at 500 MPa and 600 MPa. However, effectiveness of pressure holding time and medium temperature were limited on WBC, the color and the hardness. Therefore, ultra high pressure treatment at 200～400 MPa induced higher yield than that at other pressure levels. It is possible to control hardness of pressurized PMGA via the application at various pressure levels.