Method for chemistry testing potassium bromate in flour, amendment or food

Abstract

The invention discloses a chemical test method of potassium bromate in flour, modifying agent or food, which comprises (1), processing sample composed of adding alkali into sample, heating and ashing, dissolving in water, adding acid to adjust pH at 2-5, moving all solution into a centrifugal pipe, controlling the pH value at 1-2, centrifugally treating and taking supernatant fluid, (2), testing potassium bromate composed of adding the supernatant with oxidant, vibrating and adding organic solvent, vibrating, laying and laminating, using distilled water as blank, using spectrophotometer to check the light absorption value of the organic solvent layer and indicating that the sample contains potassium bromate when the light absorption value is not lower than 0.010. The oxidant is strong one and the organic solvent is non-polar or weak-polar organic one. The invention provides a novel, simple, quick, sensitive and stable method for chemically checking potassium bromate in flour, modifying agent or food.

Description

technical field

[0001] The invention relates to a detection method of potassium bromate, in particular to a chemical detection method of potassium bromate in flour, improver or food. Background technique

[0002] Potassium bromate is a slow oxidizing agent. Potassium bromate was once considered one of the best dough conditioners in the baking industry. It was used in bread baking. At present, potassium bromate has been banned due to its safety problems. . However, because there is no safe and effective substitute, and some small manufacturers secretly use potassium bromate, therefore, how to detect potassium bromate in flour, improvers, and food is of great significance. At present, the qualitative and quantitative methods for pure potassium bromate are very perfect in the world, but in complex mixing systems such as flour improver and flour, the test method for potassium bromate is not perfect. For example: the qualitative and quantitative detection methods of bromate in ...

Examples

Embodiment 1

[0022] 1. Sample processing

[0023] Take 100g of bromate-containing flour sample, add 0.1g of NaOH powder, mix well, put it into an evaporating dish, and carbonize it on an electric furnace. After the ashing is complete, cool down, dissolve the ashed sample with 4ml of water, and add 2mol / l H 2 SO 4 2mL, adjust the pH to 3, heat slightly to 60°C on the electric stove, transfer the solution to a 10ml centrifuge tube, and then add a small amount of water and 2mol / l H 2 SO 4 Rinse the evaporating dish, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at about 1. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0024] 2. Determination of Potassium Bromate

[0025] Transfer the above supernatant into a 60ml separatory funnel, add 0.1ml freshly prepared saturated chlorine water dropwise, add 5ml carbon tetrachloride after shaking, shake, place layers, and filter the organic solvent layer into a cuvette with absor...

Embodiment 2

[0027] 1. Sample processing

[0028] Take 2 grams of bromate-containing modifier, add 0.1g KOH powder, mix well, put it in an evaporating dish, and carbonize it on an electric furnace. After the carbonization is complete, transfer the evaporating dish to a muffle furnace, and incinerate at 520°C. After the ashing is complete, cool down, dissolve the ashed sample with 3ml of water, and add 2mol / l H 2 SO 4 1-2ml, adjust the pH to 4, heat slightly on the electric stove to 50°C, transfer the solution to a 10ml centrifuge tube, and then use a small amount of water and 2mol / l H 2 SO 4 Rinse the evaporating dish, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at about 1. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0029] 2. Determination of Potassium Bromate

[0030] Transfer the above supernatant into a 60mL separatory funnel, add 0.1ml of 2mol / l potassium permanganate solution, oscillate, add 5ml of chloro...

Embodiment 3

[0032] 1. Sample processing

[0033] Take 150 grams of steamed bread with potassium bromate, add 0.1g of NaOH powder, mix well, put it in an evaporating dish, and carbonize it on an electric furnace. After the melting is complete, cool down, dissolve the ashed sample with 5ml of water, add 1-2ml of 2mol / l hydrochloric acid, adjust the pH to 4, slightly heat to 50°C on an electric furnace, transfer the solution to a 10ml centrifuge tube, Then wash the evaporating dish with a small amount of water and 2mol / l hydrochloric acid respectively, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at 1.5. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0034] 2. Determination of Potassium Bromate

[0035] Transfer the above supernatant into a 60ml separatory funnel, add 0.1ml of hydrogen peroxide, add 5ml of benzene after shaking, shake, place and layer, the organic solvent layer is filtered with absorbent cotton into a c...

technical field

[0001] The invention relates to a detection method of potassium bromate, in particular to a chemical detection method of potassium bromate in flour, improver or food. Background technique

[0002] Potassium bromate is a slow oxidizing agent. Potassium bromate was once considered one of the best dough conditioners in the baking industry. It was used in bread baking. At present, potassium bromate has been banned due to its safety problems. . However, because there is no safe and effective substitute, and some small manufacturers secretly use potassium bromate, therefore, how to detect potassium bromate in flour, improvers, and food is of great significance. At present, the qualitative and quantitative methods for pure potassium bromate are very perfect in the world, but in complex mixing systems such as flour improver and flour, the test method for potassium bromate is not perfect. For example: the qualitative and quantitative detection methods of bromate in ...

Examples

Embodiment 1

[0022] 1. Sample processing

[0023] Take 100g of bromate-containing flour sample, add 0.1g of NaOH powder, mix well, put it into an evaporating dish, and carbonize it on an electric furnace. After the ashing is complete, cool down, dissolve the ashed sample with 4ml of water, and add 2mol / l H 2 SO 4 2mL, adjust the pH to 3, heat slightly to 60°C on the electric stove, transfer the solution to a 10ml centrifuge tube, and then add a small amount of water and 2mol / l H 2 SO 4 Rinse the evaporating dish, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at about 1. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0024] 2. Determination of Potassium Bromate

[0025] Transfer the above supernatant into a 60ml separatory funnel, add 0.1ml freshly prepared saturated chlorine water dropwise, add 5ml carbon tetrachloride after shaking, shake, place layers, and filter the organic solvent layer into a cuvette with absor...

Embodiment 2

[0027] 1. Sample processing

[0028] Take 2 grams of bromate-containing modifier, add 0.1g KOH powder, mix well, put it in an evaporating dish, and carbonize it on an electric furnace. After the carbonization is complete, transfer the evaporating dish to a muffle furnace, and incinerate at 520°C. After the ashing is complete, cool down, dissolve the ashed sample with 3ml of water, and add 2mol / l H 2 SO 4 1-2ml, adjust the pH to 4, heat slightly on the electric stove to 50°C, transfer the solution to a 10ml centrifuge tube, and then use a small amount of water and 2mol / l H 2 SO 4 Rinse the evaporating dish, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at about 1. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0029] 2. Determination of Potassium Bromate

[0030] Transfer the above supernatant into a 60mL separatory funnel, add 0.1ml of 2mol / l potassium permanganate solution, oscillate, add 5ml of chloro...

Embodiment 3

[0032] 1. Sample processing

[0033] Take 150 grams of steamed bread with potassium bromate, add 0.1g of NaOH powder, mix well, put it in an evaporating dish, and carbonize it on an electric furnace. After the melting is complete, cool down, dissolve the ashed sample with 5ml of water, add 1-2ml of 2mol / l hydrochloric acid, adjust the pH to 4, slightly heat to 50°C on an electric furnace, transfer the solution to a 10ml centrifuge tube, Then wash the evaporating dish with a small amount of water and 2mol / l hydrochloric acid respectively, transfer all the washing liquid into a 10ml centrifuge tube, and control the pH value at 1.5. Centrifuge at 2800r / min for 10min, and take the supernatant for later use.

[0034] 2. Determination of Potassium Bromate

[0035] Transfer the above supernatant into a 60ml separatory funnel, add 0.1ml of hydrogen peroxide, add 5ml of benzene after shaking, shake, place and layer, the organic solvent layer is filtered with absorbent cotton into a c...