Enhancing the quality of tapioca starch gel under cold storage using sucrose and xanthan gum
カセサート大学 農工学部 生産開発学部 親水コロイドおよびシェルフライフ研究室(タイ)
Starch at high concentrations is used for preparing food gel. The starch plays an important role in the final quality of the gel product related to three-dimensional networks after heating and cooling. To enhance the quality and shelf life of the starch gel, hydrocolloids are widely added into starch-based gel for modifying its texture and rheological properties. Since the quality of a final food product depends on the contribution from each ingredient and interaction among them, adding sugar into food formulation could modify the final product properties such as water activity reduction. Tapioca starch(TS) was selected for investigation due to its low price. Xanthan gum (Xan) was added into the formulation for improving the stability of the starch gel kept in cold storage. Sucrose (0, 10 and 20%) and Xan (0.3125%) were added in the TS (25%w/w TS and TS/Xan gels) for gel preparation. The gel quality was investigated after keeping in cold storage at 5ºC for 7 and 14 days. The hardness of TS and TS/Xan gels increased with increasing sucrose content but was retarded by Xan addition. Water separation reduction was observed in the gels containing Xan and sucrose after repeated freeze-thaw cycle treatment indicating better quality of the starch gels with the addition of sucrose and Xan. The results gained in this study could be further applied in food industry to improve the quality of starch gel.