How to distinguish the authenticity of potassium sorbate

Introduction: potassium sorbate is a kind of antiseptic additive Now most foods need potassium sorbate How to distinguish the true and false of potassium sorbate? Xiaobian will introduce you in this article In our daily life, we can't avoid contact with potassium sorbate, because there are many potassium sorbate additives in people's food, so how to identify the authenticity of potassium sorbate? Let's introduce a method to identify potassium sorbate by experiment There are two ways to distinguish potassium sorbate by experiment: 1 Nonaqueous titration (Arbitration) (1) Experimental principle: potassium sorbate interacts with perchloric acid to form white precipitate of potassium perchlorate Through the consumption of perchloric acid standard solution, the content of potassium sorbate can be calculated Thus, the amount of potassium sorbate divided by 1.33 can be converted into the amount of sorbic acid (2) Operation steps: after the sample is dried, accurately weigh about 0.3g (accurate to 0.0002g) into an iodine measuring flask with 48ml glacial acetic acid and 2ml acetic anhydride, add 2 drops of crystal glacial acetic acid indicator solution, titrate with perchloric acid standard solution until the solution turns purple to blue, and then perform blank test (3) Calculation formula: x =, where, X: the mass content of potassium sorbate in the sample; C: the actual concentration of perchloric acid standard solution, mol / L; V: the volume of perchloric acid standard solution consumed by the sample, ml; V: the volume of perchloric acid standard solution consumed by the blank, ml; 0.1502: the mass of potassium sorbate in grams equivalent to 1.00mL perchloric acid standard solution (C = 1.00mol / L); m: the mass of the sample, G (4) Conversion: content of sorbic acid x = x / 1.33 2 Two phase titration (1) Experimental principle: after potassium sorbate is dissolved in water, add ether which is insoluble in water, and titrate it with hydrochloric acid standard solution Because the solubility of sorbic acid generated by reaction in the titration process is small in water and large in ether, the sorbic acid generated by titration can be extracted into the organic phase continuously, so as to reduce the dissociation of sorbic acid and complete the titration reaction (2) Operation steps: after the sample is dried, accurately weigh 1.5g (accurate to 0.002g) into a 250ml conical flask, add 25ml of water solution to dissolve, add 50ml of ether, 10 drops of bromocresol green methyl orange (1 + 1) mixed indicator water solution, titrate with hydrochloric acid standard solution, fully shake, the water layer is from blue-green through light yellow green, yellow to obvious orange red as the end point, and conduct blank test at the same time (3) Conversion: content of sorbic acid x = x / 1.33 Food additives have almost become an indispensable problem in the process of food production It's better to use the food safety detector to test it after the completion of production Learning more food additive knowledge can bring benefits to people's diet in the future, including the function of potassium sorbate , you can log in our safety net to check Editor in charge: he xianrob