Production method for crystalline tagatose

Abstract

The invention belongs to the biological and chemical engineering fields, and particularly discloses a production method for crystalline tagatose. The method comprises the following steps: using lactose as a raw material; dissolving the lactose; hydrolyzing by acidic lactase; leaching and separating by a simulated moving bed; enabling the content of tagatose to reach up to 75% by only using calcium oxide as an isomerizing agent and phosphoric acid or CO2 as neutralization acid; and finally separating, evaporating and crystallizing the tagatose by the simulated moving bed. According to the production method for the crystalline tagatose, the condition of separating and the optimal condition of crystallizing by the simulated moving bed are determined; the purity of the obtained product reaches more than 98.5%, and the yield is over 40; and the cost and pollution are low, and the method meets the condition of industrialization production.

Description

(1) Technical field [0001] The invention belongs to the fields of biology and chemical industry, in particular to a production method of crystalline tagatose. (2) Background technology [0002] Tagatose is a rare sugar, a rare natural ketohexose, an isomer of galacturosone, and an epimer of fructose at the C-4 position. Its molecular formula is for C 6 h 12 o 6 . The pure tagatose is a white crystal with a melting temperature of 133°C, a melting point of 134°C, and a glass transition temperature of 15°C. It is easily soluble in water, and its aqueous solution is clear and colorless. It is slightly soluble in ethanol. When dissolved in water, it will cause a rise in boiling point and freezing point Reduces heat, but does not absorb heat, so it will not produce a cool taste; it can exist stably in the pH range of 3~7, is prone to Maillard reaction, and caramelization reaction can occur at a lower temperature. [0003] Tagatose products have been approved for use by th...

AI Technical Summary

Problems solved by technology

The biological enzymatic method has no pollution to the environment, but the efficiency of converting galactose into tagatose is low, which is not suitable for industrial production; the chemical method needs to use alkali metal salts or alkaline earth metals as isomerizing agents, which seriously pollutes the environment; lactose As a raw material, it also needs to be hydrolyzed into galactose and glucose with acid or enzyme. The acid also pollutes the environment, but with enzyme hydrolysis, the hydrolysis rate of lactose is low, and galactooligosaccharides are produced, which affects the recovery of tagatose. rate; galactose is used as raw material, but the price of galactose is relatively high, with an average of 150,000 yuan / ton, while the price of tagatose is less than 100,000 yuan / ton, which cannot be industrialized