Application of Hurdle Technology for Improving the Manufacturing Process of Frozen Rice Cake

• Main Authors: Chen, Ke-Wen, 陳科文
• Other Authors: Chang, Cheng-Ming
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/9j955x

碩士 === 國立臺灣海洋大學 === 食品科學系 === 106 === This study is aimed to adopt different process variables to improve shelf life of rice cake, treatments including frozen rice cake without preservatives, change frozen storage to refrigerated storage, and control environmental hygiene (lower the relative humidity, spray chlorine dioxide), same proportion degrees brix of pure rice cake and stuffing (40：40, 50：50, 60：60 °Brix), different water content of sprinkled powder (6%, 8%, 10%), different packaging material (PE, KNY/LLDPE, KNY/LLDPE and deoxidizer) as hurdle factors of the manufacturing process of rice cake. Samples were taken at zeroth, fourth, seventh, tenth, fourteenth, fifteenth day, and quality criteria including moisture, water activity, total plate count, yeast and mold, hardness, springiness, chewiness of rice cake under refrigerated storage were analyzed. The results demonstrated that spray 1000 ppm chlorine dioxide was significantly more effective on control air-borne bacteria counts than control the relative humidity under less than 60%. During refrigerated storage, the moisture of each group showed a tendency of rise slowly, while the water activity did not change significantly. Higher concentration (in terms of Brix), low moisture content of sprinkled powder, low permeability packaging material and deoxidizer showed the better hurdle effects on inhibition of microbial growth. Thus, the combination of above hurdle factors, the shelf life could be extended to 15 days under refrigeration as compared to 4 days without adding preservatives. In terms of textural profile analysis, hardness and chewiness were mainly affected by Brix, followed by packaging materials, the variations in springiness was not significantly affected by the hurdle factors. Comprehensively consider both microbial growth and maintenance of texture (lower hardness and higher springiness and chewiness), combined 50：50 °Brix of pure rice cake and stuffing, 8% sprinkled powder, KNY/LLDPE and deoxidizer were the most suitable formula for the product under refrigerated storage.