Thermal stability of chicken skin gelatine gels in comparison with commercial gelatines

Abstract

Gelatine is a partial hydrolysate of collagen obtained from pre-treated raw material extracted in distilled water at higher temperatures. Its excellent functional properties predestine it for various applications not only in the food industry but also in further sectors. Technological conditions of the preparation process may influence gelatine structure and thus its quality. That is mainly assessed by gelatine gel strength and its thermal stability which was tested in this study. Chicken skin gelatines (CSG) were gained by enzymatic pre-treatment of the feedstock followed by extraction at five different temperatures. Series of CSG gels were prepared and their thermal stability was tested at three different temperatures (23, 29 and 35 degrees C). Changes in gelatine gel strength were monitored. What is more, results of CSG were compared with commercial beef and pork food-grade gelatines. The highest thermal stability was observed within CSG70 (CSG extracted at the temperature of 70 degrees C) at the temperature of 23 degrees C, within CSG50 at the temperature of 29 degrees C and CSG40 at the temperature of 35 degrees C. The lowest thermal stability was recorded in CSG80. These results have shown that thermal stability of CSG gels is comparable or even better than the one of commercial gelatines. Therefore, CSG provides a wide range of applications, particularly in the food industry, i.e. in confectionery.