CN103182248A - Method for reducing metal content in shellfish extracting solution by combining ultrafiltration and electrodialysis technology - Google Patents

Abstract

The invention discloses a method for reducing metal content in shellfish extracting solution, which mainly combines two membrane methods of ultrafiltration and electrodialysis with a pH value adjusting method. The method can be used for effectively reducing the content of metals such as cadmium, lead and chromium in the shellfish extracting solution, and cannot affect original relish and nutrient content of the extracting solution at the same time, has the advantages of easy operation, high efficiency and so on, and enables large scale industrialized production to come true, so that the method has various advantages, is particularly suitable for the popularization and application in the local field, and has very broad market prospect.

Description

Ultrafiltration, electrodialysis complex technique reduce the method for heavy metal in the shellfish extract

Technical field

The present invention relates to a kind of food and processing of aquatic products technology, particularly a kind of method that reduces heavy metal in the shellfish extract.

Background technology

Along with the raising of people's living standard, very big variation has also taken place in people's consumption idea, and is also more and more higher to the security requirement of food.At present, the converted products of some marine products on the market, as the shellfish flavoring, the marine product health food of high added value etc., owing to contain a certain amount of heavy metal in its raw materials for production, under the effect of the enrichment effect of heavy metal, final product tends to occur the situation of heavy metals exceeding standard, if people are edible this group food often, the heavy metal poisoning event might take place.Shellfish is filter food, heavy metal in the environment is very easy at its body accumulation, and heavy metal is difficult for removing, and therefore there is the hidden danger that endangers health of human body in the food of being processed into as raw material with shellfish or shellfish associated products, need be controlled effectively.At present, mainly concentrate on quality control in the breeding process for the heavy metal removing method of seashell products, lay particular emphasis on live body and remove, but the method is strict to breeding environment, aquaculture cost is higher.

Traditional heavy metal removing method comprises flocculence, ion-exchange-resin process, electroosmose process, ultrafiltration, absorption method etc.Though it is ripe that resin method removes heavy metal, resin uses the back easily to lose efficacy, and need regenerate, and will expend a large amount of acid or alkali in the regenerative process, causes environmental pollution.Ultrafiltration and electroosmose process all belong to embrane method, have energy consume low, operating maintenance convenient, free from environmental pollution, treating capacity greatly, can be recycled, be beneficial to advantage such as suitability for industrialized production.Find by literature search, heavy metal removing method in various extracts or the edible liquid there are " method that reduces heavy metal in the mussel boiling liquid with shitosan " (CN 10101116 B), " electroosmose process removes the method for heavy metal in the plant extraction liquid " (CN 101108306 A), " method of content of heavy metal lead in the ion-exchange subduction sea buckthorn juice raw material " (CN 101176565 B), " be used for removing compound and the application thereof of heavy metal ion " (CN 101693189 B), " application of chelating type chemically modified chitosan heavy metal ion in removing water " (CN 101846958 B), " removing the method for heavy metal ion in the water " (CN 101823007 B).And utilize ultrafiltration-electrodialysis complex technique also not find consist of the research that heavy metal removes in the main shellfish extract with albumen, peptide, amino acid, carbohydrate etc.

Summary of the invention

The present invention is in order to solve the above-mentioned deficiency of existing in prior technology, proposes a kind ofly can improve product quality, simple to operate, reusable and be convenient to the method for heavy metal in the reduction shellfish extract of suitability for industrialized production.

Technical solution of the present invention is: a kind of ultrafiltration, electrodialysis complex technique reduce the method for heavy metal in the shellfish extract, and it is characterized in that: described method may further comprise the steps

A, at first be that 50-100 purpose filter cloth carries out one-level and filters with the shellfish extract by the order number, and then be that 300-350 purpose filter cloth carries out cascade filtration by the order number, collect filtrate,

The NaOH of b, the HCl that utilizes 0.1N or 0.1N regulates filtrate pH value to 4.5-7, select for use and be furnished with the ultrafiltration apparatus that molecular weight is the hollow fiber ultrafiltration membrane of 10000-100000Da, filtrate is squeezed into ultrafiltration apparatus carry out ultrafiltration, and collect through filtrate, regulate the concentration that sees through amino-acid nitrogen in the filtrate with distilled water, make its content control in 2%, utilize the HCl of 0.1N or the NaOH of 0.1N to regulate filtrate pH value to 4-8 again

C, will be through hyperfiltration treatment and the input of the filtrate after regulating pH value electrodialysis plant, the anion and cation exchange membrane of electrodialysis plant is heterogeneous ion-exchange membrane, operating voltage range is 10-100V, flow is 1-7L/min, cycle-index is 1-4 time, collect desalination solution, obtain to reduce the shellfish extract of heavy metal.

The present invention compares with prior art, has following advantage:

The method disclosed in the present mainly is with ultrafiltration and two kinds of embrane methods of electrodialysis, combines with pH value regulating measure.This method can effectively reduce the content of heavy metal cadmium, lead and chromium in the shellfish extract, also can not influence the original local flavor of extract and nutritional labeling simultaneously, has simple to operate, efficient advantages of higher, can realize large-scale industrial production.Therefore we can say that it has possessed multiple advantage, be particularly suitable for applying in the art that its market prospects are very wide.

The specific embodiment

Below the specific embodiment of the present invention will be described.

Embodiment one

Get the 3kg oyster, add 4.5kg water and 30g papain (enzyme work is 20,000 U/g) after the homogenate, regulate pH value to 6.0 with the HCl of 0.1N and the NaOH of 0.1N, deactivation behind hydrolysis 120min under 55 ℃ of conditions obtains the oyster enzymolysis liquid.Enzymolysis liquid is crossed 100 mesh sieves and 330 mesh sieves respectively, collect filtrate.After regulating filtrate pH value to 6.5 with the NaOH of the HCl of 0.1N and 0.1N, filtrate is carried out ultrafiltration (the filter membrane molecular weight is 30000Da), collect through liquid.Utilize potentiometric determination to see through the content of amino-acid nitrogen in the liquid, and utilize distilled water adjustment, make its content in 1%.Utilizing the NaOH of the HCl of 0.1N and 0.1N to regulate the pH value that sees through liquid is 5.Ultrafiltration after the adjusting pH value is seen through liquid input electrodialysis plant.Electrodialytic anion and cation exchange membrane is heterogeneous ion-exchange membrane, and operating voltage is 70v, flow 4L/min, and cycle-index is 2 times, collects desalination solution.

Utilize the content of cadmium, lead and chromium in the atomic absorption spectrophotometer gained desalination solution, the content of amino-acid nitrogen in the potentiometric determination desalination solution, the result shows, this method is 98.7% to clearance plumbous in the oyster hydrolyzate, clearance to cadmium is 56.4%, clearance to chromium is 68.5%, and the amino-acid nitrogen storage rate is 89.6%.

Embodiment two

Get 3kg scallop processing waste (comprising scallop body, internal organ and gonad etc.), add 6kg water and 20g papain (enzyme work is 20,000 U/g) and 10g composite flavor enzyme (enzyme work is 1.8 ten thousand U/g) after the homogenate, regulate pH value to 6.0 with the HCl of 0.1N and the NaOH of 0.1N, deactivation behind hydrolysis 120min under 50 ℃ of conditions obtains scallop discarded object enzymolysis liquid.Enzymolysis liquid is crossed 80 mesh sieves and 350 mesh sieves respectively, collect filtrate.After regulating filtrate pH value to 7 with the NaOH of the HCl of 0.1N and 0.1N, filtrate is carried out ultrafiltration (the filter membrane molecular weight is 30000Da), collect through liquid.Utilize potentiometric determination to see through the content of amino-acid nitrogen in the liquid, and utilize distilled water adjustment, make its content in 0.6%.Utilizing the NaOH of the HCl of 0.1N and 0.1N to regulate the pH value that sees through liquid is 5.5.Ultrafiltration after the adjusting pH value is seen through liquid input electrodialysis plant.Electrodialytic anion and cation exchange membrane is heterogeneous ion-exchange membrane, and operating voltage range is 80v, flow 3L/min, and cycle-index is 3 times, collects desalination solution.

Utilize the content of cadmium, lead and chromium in the atomic absorption spectrophotometer gained desalination solution, the content of amino-acid nitrogen in the potentiometric determination desalination solution, the result shows, this method is 96.5% to clearance plumbous in the scallop discarded object enzymolysis liquid, clearance to cadmium is 64.2%, clearance to chromium is 70.3%, and the amino-acid nitrogen storage rate is 87.7%.

Claims (1)

1. a ultrafiltration, electrodialysis complex technique reduce the method for heavy metal in the shellfish extract, and it is characterized in that: described method may further comprise the steps

A, at first be that 50-100 purpose filter cloth carries out one-level and filters with the shellfish extract by the order number, and then be that 300-350 purpose filter cloth carries out cascade filtration by the order number, collect filtrate,

The NaOH of b, the HCl that utilizes 0.1N or 0.1N regulates filtrate pH value to 4.5-7, select for use and be furnished with the ultrafiltration apparatus that molecular weight is the hollow fiber ultrafiltration membrane of 10000-100000Da, filtrate is squeezed into ultrafiltration apparatus carry out ultrafiltration, and collect through filtrate, regulate the concentration that sees through amino-acid nitrogen in the filtrate with distilled water, make its content control in 2%, utilize the HCl of 0.1N or the NaOH of 0.1N to regulate filtrate pH value to 4-8 again

C, will be through hyperfiltration treatment and the input of the filtrate after regulating pH value electrodialysis plant, the anion and cation exchange membrane of electrodialysis plant is heterogeneous ion-exchange membrane, operating voltage range is 10-100V, flow is 1-7L/min, cycle-index is 1-4 time, collect desalination solution, obtain to reduce the shellfish extract of heavy metal.