Effects of temperature and immersion time on rehydration of osmotically dehydrated pork meat

The aim of this work was to study the changes in osmotically dehydrated (OD) pork meat during rehydration. Meat samples (lxlxlcm cubes) were osmotically treated in two solutions: (1) solution with 350g of NaCI and 1200g of sucrose diluted in I I of distilled water and (2) sugar beet molasses (80 °Brix) solution at 23±2°C for 1, 2, 3 and 4 hours. In both cases, the solution to sample mass ratio was 10:1 to avoid significant dilution of the medium by water removal. After being osmotically dehydrated, meat samples were rehydrated by immersing meat cubes in water bath at constant temperature (20, 40 and 60 °C). The samples were removed after different immersion periods (15, 30, 45 and 60 min) and examined for mass and volume gain and rehydration percentage was calculated. After relatively short time (15 min), significant weight and volume gains were observed for both treatments. Process temperature was the most significant variable affecting final dry matter content and rehydration kinetics. At the end of rehydration process, conducted at 20 °C and 40 °C, a significant recovery in mass was observed, although the values were lower than for fresh meat. Ruptured and shrunken meat tissue produced as the result of OD had reduced its ability to absorb water. Rehydration percentage at 20 °C for molasses solution was 24.11%, and for sucrose-salt solution was 26.19%. However, rehydration at 40° C brings higher mass gain in case of molasses as a solution (11.33%) compared with sucrose-salt solution (7.88%). Results obtained at 60 °C were negative which means that rehydration didn't take place. The best conditions for meat rehydration were obtained using a temperature of 20 °C and time of 60 min. Volume of samples increased almost linearly with weight increment