การผลิตน้ำกระท้อน Sandoricum indicum Cav. เข้มข้นและน้ำกระท้อนเสริมแคลเซียมและวิตามินดี / นิภาพร เส็งคำปาน = Production of concentrated santol Sandoricum indicum Cav. juice and santol juice supplemented with calcium and vitamin D / Nipaporn Sengkhamparn
This study focused on the production of concentrated santol Sandoricum indicum Cav. juice and santol juice supplemented with calcium and vitamin D. The steam blanching time of, 1, 3, 5, 7 and 9 minutes were studied for inactivating polyphenol oxidase (PPO). Later, the three levels of the pressed time, 9, 12 and 15 minutes at 100 psi by hydraulic press were studied and the best time selected by determining maximum yield. Later, the heating condition, 70 90 ํC for 60-120 seconds were used for inactivating pectin methylesterase (PME) and the optimum condition selected by determining PME activity and color (L*, +a*, +b*) of the santol juice. Then, the optimum concentrated temperatures of, 60, 70 and 80 ํC at 50 mbar were studied and the best temperature selected by comparing color and sensory quality of the resulting concentrated juice with those of the original santol juice. Then, the cloud stabilization method, comprising homogenization at 1000 psi, xanthan gum at 0.1 %w/v, homogenizing at 1000 psi in combination with xanthan gum at 0.1 %w/v, were studied. The best method was selected by comparing cloud stability and sensory quality of the product with that of the control santol juice. Then, supplementation of the juice with calcium lactate gluconate at 120, 160 and 200 mg calcium/100 ml and vitamin D[subscript 3] at 1.14 microgram/100 ml was carried out and the best concentration selected via physical and sensory quality of the supplemented juice. Finally, storage stability of the concentrated santol juice, at 10, 27, 35 and 55 ํC was studied and the shelf-life predicted at 0 ํC. The storage stability of the santol juice supplemented with calcium and vitamin D[subscript 3], at 5-8 ํC, was later studied. The results showed that the optimum steam blanching time was 5 minutes and the highest quantity of santol juice was obtained by using automatic juice extractor, followed by pressing with hydraulic press for 12 minutes. The optimum heating condition found for inactivating PME was 92 ํC at 60 seconds. The best concentrating temperature which provided the product with a good color and sensory quality was 70 ํC. The best cloud stability method selected was incorporation of 0.1 % w/v xanthan gum, with this method, the product had a good sensory quality and not seperated for 30 days. The final santol juice supplemented with 160 mg /100 ml of calcium and vitamin D[subscript 3] at 1.14 microgram/100 ml was highly accepted by the trained sensory panelists. The concentrated santol juice could be stored in glass bottle at 10 ํC for at least 30 days, 27 ํC for 18 days, 35 ํC for 12 days and 55 ํC for 6 days and the shelf life predicted at 0 ํC was 58 days. Santol juice supplemented with calcium and vitamin D could be stored in glass bottle for at least 4 weeks at 5-8 ํC, at the end of the storage period, the chemical, microbiological and sensory qualities of product were still being acceptable.
