Journal of Food Engineering, Vol.55, No.1, 35-39, 2002
Rheological behaviour of blood plasmas concentrated by ultrafiltration and by evaporation in relation to liquid-gel transition temperature
Dehydrated blood plasma finds use as a protein ingredient for its gelation properties especially in meat derivative products. Generally, blood is concentrated by either ultrafiltration or evaporation under reduced pressure. The resulting pH and ash concentration (mineral salts and sodium citrate) differ, so modifying the gelation properties of the products. We studied the influence of pH, NaCl concentration and time-temperature pattern on the liquid-to-gel transition temperature; T-g of the blood plasma in these two processes. We showed that at all the NaCl concentrations, increasing the pH from 4 to 7.8 increased the blood plasma T-g from 35 to 54 degreesC. NaCl concentrations in the range 0.2-1.65 (mass%) had no significant effect on this temperature, and particular time-temperature heating procedure suppressed the T-g. This last result is of particular interest for pasteurisation. (C) 2002 Elsevier Science Ltd. All rights reserved.