Quick detecting method for sudan red in food

[0020] Example 1

[0021] Weigh 10 g of red pepper powder into a centrifuge tube, add 30 mL of water for dilution, add 10 mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3, shake for 1 min, extract by ultrasonic for 15 min, centrifuge at 3500 r/min for 1 min, filter, The residue was extracted twice with 10 mL and 5 mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3, respectively, and the extracts were combined; the extract was placed in a distillation flask, and the distillation flask was placed in a 40°C water bath for rotary evaporation, Or add anhydrous sodium sulfate to the bottle for dehydration, filter and evaporate to dryness naturally; add 1 mL of acetone to dissolve the obtained in the previous step, pass through a polyamide thin-layer plate, and use chloroform:acetone:acetic acid=6:1:1 as a developing agent, The obtained crystals were dried and placed in a sampling bottle; acetonitrile was added to the upper sampling bottle to make the volume to 5 mL, shaken for 10 min, and allowed to stand for 20 min. % Formic acid:acetonitrile=80:20 as mobile phase, column temperature at 28°C, flow rate of 1.0ml/min, constant flow, and detection wavelength of 230nm.

[0022] Example 2

[0023] Weigh 5g of ketchup into a centrifuge tube, add 20mL of water for dilution, add 10mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3, shake for 1min, extract by ultrasonic for 15min, centrifuge at 5000r/min for 1min, filter, and remove the residue. Extract twice with 10mL and 5mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3 respectively, and combine the extracts; place the extracts in a distillation flask, and place the distillation flask in a 40°C water bath for rotary evaporation, or Add anhydrous sodium sulfate to the bottle for dehydration, filter and evaporate to dryness naturally; add 1 mL of acetone to dissolve the result obtained in the previous step, pass through a polyamide thin-layer plate, and use chloroform:acetone:acetic acid=6:1:1 as a developing agent, the obtained The crystals were dried and placed in a sampling bottle; acetonitrile was added to the upper sampling bottle to make the volume to 5 mL, shaken for 10 minutes, and allowed to stand for 20 minutes. Formic acid:acetonitrile=80:20 was used as the mobile phase, the column temperature was 28°C, the flow rate was 1.0ml/min, the constant flow, and the detection wavelength of 230nm.

[0024] Example 3

[0025] Weigh 20g of chili oil in a centrifuge tube, add 25mL of water for dilution, add 30mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3, shake for 1min, extract by ultrasonic for 15min, centrifuge at 5000r/min for 1min, filter, and remove the residue. Extract twice with 10mL and 5mL of a mixed solvent of n-hexane and acetone with a volume ratio of 5:3 respectively, and combine the extracts; place the extracts in a distillation flask, and place the distillation flask in a 40°C water bath for rotary evaporation, or Add anhydrous sodium sulfate to the bottle for dehydration, filter and evaporate to dryness naturally; add 1 mL of acetone to dissolve the result obtained in the previous step, pass through a polyamide thin-layer plate, and use chloroform:acetone:acetic acid=6:1:1 as a developing agent, the obtained The crystals were dried and placed in a sampling bottle; acetonitrile was added to the upper sampling bottle to make the volume to 5 mL, shaken for 10 minutes, and allowed to stand for 20 minutes. Formic acid:acetonitrile=80:20 was used as the mobile phase, the column temperature was 28°C, the flow rate was 1.0ml/min, the constant flow, and the detection wavelength of 230nm.