Optimisation of the Gelatine Spray Drying Process using Response Surface Methodology

Drying process is a final process in the production of gelatine. Traditional method applied in the industry is more complicated to operate compared with spray drying method. Gelatine powder can be obtained by the spray drying process. However it is rarely used because it might lead to lower quality of gelatine due to protein degradation. The objective of this work was to optimize the production of gelatine powder from spray drying using response surface methodology (RSM). Commercial type B gelatine (bloom strength 151-160) from cattle bones and pilot-scale spray dryer was used in this study. Two independent variables were considered namely feed concentration (6% (w/w) – 15% (w/w)) and inlet temperature (150oC-170oC). The dependent variables were yield, moisture content and gel strength of gelatine powder. The results showed that different feed concentration and inlet temperature affect all three responses where feed concentration was the main factor affecting the yield of gelatine powder. The higher the feed concentration of gelatine, the lower the resulting yields. The gelatine powder produced has Bloom strength between 149 and 173 which was slightly lower than the Bloom strength of commercial gelatine. The optimum conditions obtained from RSM analysis were feed concentration 9.23% (w/w) and inlet temperature of 170oC where the yield of gelatine produce was 22.15% with moisture content 3.81% and gel strength 168.5. It was found that deviation from the predicted value was 0.09% for yield, 3.05% for moisture content and 0.78% for gel strength.