A method for removing cadmium from whole grain rice

Abstract

The invention discloses a method for removing cadmium in whole rice. The method comprises the following steps: (1) removing impunity, (2) rick filling and cadmium dissolving, (3) separation, (4) neutralization, desalting, leaching and (5) drying, so as to obtain the cadmium-removed whole rice. In the method, cadmium complex is isolated from the rice through cooperation of a physical method and a chemical method, cadmium complex solution is separated in a gradient way step by step by a multi-level back flow separation method, and the content of cadmium in the rice is effectively reduced under the conditions that the appearance of the rice is kept complete and the nature difference is slight. Moreover, the method for removing cadmium in whole rice is simple in operation and low in cost, is suitable for large-scale industrial production and is worthy to be popularized and applied.

Description

technical field [0001] The invention belongs to the technical field of grain deep processing, and in particular relates to a method for removing heavy metal cadmium in whole-grain rice. Background technique [0002] China is the world's largest rice producer, with a rice output of 189 million tons in 2008, and rice is my country's largest food crop. However, the quality of soil in various places is directly related to the quality of edible rice. However, the adsorption effect of rice on heavy metal pollution is obviously stronger than that of other crops such as corn and soybean. Therefore, the rice is processed through deep processing to obtain high-quality products while removing heavy metals, which also increases the added value of rice utilization. [0003] Heavy metals in rice are mainly combined with amino acids in a chelated state. It is reported that heavy metals in plants are mainly combined with ligands formed by metallothionein, and some are combined with ligands...

AI Technical Summary

Problems solved by technology

[0006] The invention patent of CN201310140019.1 discloses a decadmium-removed rice protein and its preparation method and application. The main steps are to use rice as raw material, remove the starch with high-temperature amylase to obtain rice dregs, and then use acid solution for decadmium treatment , the acid used is one of food-grade acetic acid, citric acid, malic acid, lactic acid, tartaric acid, oxalic acid, phosphoric acid, and the addition amount is that rice dregs and acid solution are mixed in a weight ratio of 1:2-5. In this step, the acid It only plays the role of adjusting the pH value; the acid solution with a large amount of acid and pH<4 has a negative effect on the quality of the protein; the rice protein obtained by centrifugation is directly washed with water, because the pH value increases, the cadmium dissolved in the solution The ions are recombined with rice protein, which reduces the efficiency of cadmium removal in the final product; and the supernatant and washing liquid also contain more acid solution, which is not considered in the invention patent that its discharge will pollute the environment

Images