Isolation of Gellan Gum from Foods by Use of Monovalent Cations

摘要

ABSTRACTGellan gum added to foods was recovered by precipitation with 2M NaCl. The precipitate was trapped on glass wool, washed with 1M salt solution and eluted with boiling 40 H2SO4or boiling 2 × 10−4N NaOH. Elution with dilute NaOH was as effective as use of 40 H2SO4, except with dog food, mayonnaise and salad dressing. The hydrocolloid content of the eluate was determined by the carbazole test. Recoveries from milk, beverages, salad dressing and other foods ranged from 75–94 (reproducibility 2–4). The preferred cations for precipitation were Na+>K+>Li+>NH4+. For the anions, the order was CO3−