Acidification-hydration degumming experiments were carried out with commercially available common crude rapeseed oil, crude sunflower seed oil, crude soybean oil and crude peanut oil as experimental objects, and the degumming effects of food grade wet and thermal phosphoric acid (85%) on four vegetable oils were compared. The results showed that the optimal conditions for the degumming of vegetable oils were obtained as follows: degumming temperature 50 ℃, dosage of phosphoric acid 0.3% (oil mass), acidification time 10 min, dosage of water 6% (oil mass) and hydration time 20 min for crude rapeseed oil; degumming temperature 65 ℃, dosage of phosphoric acid 0.4% (oil mass), acidification time 20 min, dosage of water 4% (oil mass) and hydration time 40 min for crude sunflower seed oil; degumming temperature 50 ℃, dosage of phosphoric acid 0.3% (oil mass), acidification time 15 min, dosage of water 4% (oil mass) and hydration time 30 min for crude soybean oil; degumming temperature 75 ℃, dosage of phosphoric acid 0.4% (oil mass), acidification time 10 min, dosage of water 3% (oil mass) and hydration time 30 min for crude peanut oil. Under the optimal conditions, the average degumming rates of crude rapeseed oil, crude sunflower seed oil, crude soybean oil and crude peanut oil degummed by food grade wet phosphoric acid were 95.95%, 64.04%, 83.59% and 6629%, respectively, while they were 95.99%, 63.12%, 83.30% and 66.68% respectively by food grade thermal phosphoric acid. There was no significant difference in the degumming rates of the four vegetable oils between wet phosphoric acid and thermal phosphoric acid. Therefore, the effect of food grade wet and thermal phosphoric acid on the degumming of vegetable oil was basically the same. |