Research On Extraction Technique And Purification Of Phytic Acid From Peanut Meal

Phytic acid is a natural phosphorus-containing organic compound, which widely exists in cereals, pulses and the seeds of oil crops. Its main form is calcium and magnesium double salt and is usually extracted from some vegetables which contain abundant phytic acid, such as rice bran, rapeseed. It has attracted important attention and was used generally as a kind of subtle chemical products in food industry, environment protection, medical treatment and commodity chemistry because of its unique chelation with metals and natural anti-oxidization. Therefore, the exploration of phytic acid from vegetables has a broad prospect.Phytic acid extraction processing and purification was studied from peanut meal in this experiment. Firstly, three different extracting methods was used to optimal process conditions and got the optimum parameters, then static adsorption and elution of phytic acid by different macroporous resins were studied so as to choose the best from them to research dynamical adsorption and elution. At last, the structure of phytic acid was also studied. The main conclusions of the experiment were as follows:(1) water bath heating extraction process:on the basis of single-factor experiments, the optimum conditions for the extraction of phytic acid from peanut meal were obtained through Box-Behnken center-united experiment design and response surface methodology. The influential factors of concentration of hydrochloric acid, extraction temperature, extraction time and ratio of liquid to material were evaluated. The results showed that the optimum conditions for technique of Response Surface Method were as follows:the concentration of hydrochloric acid 0.01mol/L, extraction temperature 32℃, the extraction time 83min, the ratio of liquid to material 13:1, and the yield of phytic acid from peanut meal 1.5% on the above conditions.(2) ultrasonic wave-assisted extraction: on the basis of single-factor experiments, the optimum conditions for the extraction of phytic acid from peanut meal were obtained through Box-Behnken center-united experiment design and response surface methodology. The influential factors of ultrasonic temperature, ultrasonic time, ultrasonic power, ratio of liquid to material and concentration of hydrochloric acid were evaluated. The results showed that the optimum conditions for technique of Response Surface Method were as follows:ultrasonic temperature 40℃, ultrasonic time 24min, ultrasonic power 72W, ratio of liquid to material 11:1 and concentration of hydrochloric acid 0.01 mol/L, and the yield of phytic acid from peanut meal 1.48% on the above conditions.(3) microwave-assisted extraction:on the basis of single-factor experiments, the optimum conditions for the extraction of phytic acid from peanut meal were obtained through orthogonal design. The influential factors of concentration of hydrochloric acid, microwave time, microwave power and ratio of liquid to material were evaluated. The results showed that the optimum conditions for technique of Response Surface Method were as follows:concentration of hydrochloric acid 0.01mol/L, microwave time 2min, microwave power 128W, ratio of liquid to material 16:1, and the yield of phytic acid from peanut meal 1.48% on the above conditions.(4) static adsorption and elution: the performances of absorption and elution by kinds of macroporous resins to the phytic acid from peanut meal were studied. D315 resin was chosen to explore the static adsorption condition. Based on static method, the influencing factors such as equilibrium time, temperature, pH and concentration and time of elution were studied. The results showed that the static adsorption and elution index were 53.30% and 95.36% respectively. The optimal conditions were:adsorption time 2h, temperature 25℃, pH 3 and elution concentration of NaOH 1.0mol/L, time 3h.(5) dynamic adsorption and elution: macroporous resin D315 in the dynamic adsorption and elution performances of phytic acid were studied. Resin height, sample concentration, sample flow rate on the impact of resin adsorption and eluant concentration and flow rate on the impact of resin elution were examined. The results showed that: the height to diameter ratio 11.2, the sample concentration 5.24mg/mL and the sample flow rate 1.0mL/min were better for adsorption; concentration of NaOH 1.0mol/L and the eluting flow rate 1.0mL/min were better for elution. (6) qualitative analysis and quality test: after purifying, the structure of phytic acid was determined by Infra-red and the quality was tested. The IR spectrum of phytic acid in my experiment was contrast to standard spectrum and what was extracted was confirmed to be phytic acid.