National food safety standard -
Food additive - Edible tannin
1 Scope
This standard is applicable to edible tannin, a food additive whose main ingredient is tannic acid, which is extracted and processed from Galla chinensis by ethanol or ethyl acetate.
2 Technical requirements
2.1 Sensory requirements
The sensory requirements shall meet those specified in Table 1.
Table 1 Sensory requirements
Item Requirement Test method
Color and luster Yellowish white to light brown Take an appropriate amount of specimen into a white enamel tray, observe its color, luster and condition in natural light, and smell it
Condition Powder
Odor Odorless, or with a slight characteristic odor
2.2 Physical and chemical indexes
The physical and chemical indexes shall meet those specified in Table 2.
Table 2 Physical and chemical indexes
Item Index Test method
Tannic acid content (on dry basis), w/% ≥ 96.0 A.3 in Annex A
Loss on drying, w/% ≤ 9.0 Direct drying method in GB 5009.3a
Ignition residue, w/% ≤ 1.0 A.4 in Annex A
Gum or dextrin Passed the test A.5 in Annex A
Resinous substance Passed the test A.6 in Annex A
Lead (Pb)/(mg/kg) ≤ 2.0 GB 5009.75 or GB 5009.12
Residual solvent (ethyl acetate)b/(mg/kg) ≤ 25 A.7 in Annex A
a The drying temperature is 105℃±2℃ and the drying time is 2h.
b Only for products with ethyl acetate as extraction solvent.
Annex A
Test methods
A.1 General requirements
Unless otherwise specified in this standard, the reagents used are analytical reagents; any standard volumetric solution, standard solution for impurity determination, and preparations and products used shall be prepared in accordance with the requirements of GB/T 601, GB/T 602 and GB/T 603; and the test water shall meet the requirements for Grade 3 water specified in GB/T 6682. The solutions used in the test refer to aqueous solutions when the solvents used for their preparation are not specified.
A.2 Identification test
A.2.1 Ferric chloride test
After a small amount of 90g/L ferric chloride (FeCl3·6H2O) solution is added to 100g/L specimen solution, the solution shall turn bluish black or/and show flocculent precipitates.
A.2.2 Precipitation test
After 1% albumin or gelatin solution is added to 100g/L specimen solution dropwise, the solution shall show gray-white flocculent precipitates.
A.3 Determination of tannic acid content (on dry basis)
1 Scope
2 Technical requirements
Annex A Test methods
Annex B Reference gas chromatograms
