Low-methoxy pectin
Production of low-methoxy pectin methods include alkaline, acid and enzymatic three kinds. Are presented alkaline and enzymatic two.
1. Soda concentrate the pectin into the stainless steel pot, adjust ph ammonium hydrogen oxidation to 10.5,15 ℃ under the constant temperature maintained 3h. Together with an equal volume of 95% alcohol and the amount of hydrochloric acid, so that ph down to 5 or so. Stirring after standing 1h, filter out sediment pectin, drained, then were treated with 50% and 95% alcohol each washing one time, spread on baking dry pressure plate, a vacuum dryer at 65 ℃ in dry, remove Ground, packaging is finished. Yield of about 90% of the amount of pectin.
2. Pectin esterase enzyme that is used to extract low-methoxy pectin fat. Fruit Research Institute, Guangdong Province, Cai river, etc. (1996) successfully developed using low-fat enzyme extract pectin from the peel of industrial production technology. With the traditional alkaline and acid compared with the process easy to control, high product quality, save energy and reduce costs, etc., is a brief introduction to the law, the process is as follows:
Peel crush → → → degreasing → washing → mention plastic filter press filter press → Precipitation → → → filter press desalination ethanol washing → drying → crush → finished product.
Minced raw: the raw material pieces and stir 3 ~ 5mm size.
Washing: 50 ℃ water soak 30min, centrifuged, then rinse 2 or 3 times, until the eluate was colorless so far.
 Degreasing: Add appropriate amount of sodium carbonate in order to activate the endogenous pe enzyme peel, to skim. Process conditions with the temperature 50 ℃, time 1h, ph7.0, sodium carbonate 7g/kg fresh skin (25g/kg dry skin) combination is the best.
Put glue: hydrochloric acid (adjusted ph1.7 ~ 2.0) at 95 ℃ under the raised gum.
Precipitation: Precipitation cacl2 adding appropriate amount of pectin.
 Desalination ethanol washing: the hydrochloric acid, oxalic acid ratio of 1:3 mixture of desalination in the alcohol solution, and after repeated ethanol washing, drying and grinding: at 60 ℃ under vacuum drying, drying of pectin with results of powder grinding mill. The law rarely peel pectin yield of 3.5% to 4%, dry peel of 12% to 15%, gel degree 100 ± 5, fat of less than 50%, reaching U.S. fcc quality standards.