การลดความขมในน้ำสัมโดยใช้ไคโตซาน

• 主要作者: สุพัตรา รักษาพรต
• 其他作者: ขันทอง สุนทราภา
• 格式: Theses and Dissertations
• 語言: Thai
• 出版: จุฬาลงกรณ์มหาวิทยาลัย 2004
• 主題: น้ำสัมเขียวหวาน; ความขม; ไคโตแซน
• 在線閱讀: https://digiverse.chula.ac.th/Info/item/dc:35548
• 機構: Chulalongkorn University

Chitosan prepared from shrimp shells were used to remove the bitter limonin in mandarin orange juice. The degree of deacetylation, average molecular weight, surface area and average pore diameter of prepared chitosan were 74.4+-1.0%, 1.3x10[superscript 6] Dalton, 6.0 m[superscript 2]/g. and 44.7 A, respectively. They were tested for debittering in 3 different processes, i.e., membrane, packed bed and stirred tank. It was found that stirred tank was the most appropriate process. The chitosan was sized in the range of 500-850 micrometre. The optimum conditions were at 40 rpm. (Re = 148) for 10 mins., and the chitosan flakes/orange juice ratio of 1:20 by w/v. It could reduce the limonin content from 4.1+-0.2 to 2.7+-0.3 ppm. or 32.7+-8.9%. There were no significant changes in colour ([delta]E), the total soluble solids (Brix) and vitamin C (ascorbic acid). But the acid content (%citric acid) was decreased from 0.5+-0.0 to 0.2+-0.0 or 66.7+-3.0%, and the pH of orange juice was increased from 4.3+-0.0 to 5.5+-0.5. It was also found that with an increase in the degree of deacetylation of chitosan from 74.4+-1.0 to 83.4+-1.2%, the limonin reduction was increased 29.5+-15.4%. By crosslinking the chitosan flakes with sulfuric acid, limonin reduction was deteriorated. The mechanism of debittering was due to hydrogen bond between amino group of chitosan and lactone group of limonin