GB 29927-2013Food additive -- Oxidized starch (English PDF)

2.1 Raw materials

2.1.1 Raw materials

Food starch should be consistent with national standards or industry standards-related products.

2.1.2 Accessories

2.1.2.1 should meet the national standards or industry standards or the relevant provisions of the relevant requirements of the product.

2.1.2.2 oxidant type and amount. sodium hypochlorite, chlorine content of not more than dry starch content of 5.5%.

2.2 Sensory requirements

Sensory requirements shall comply with the requirements of Table 1.

Table 1 Sensory requirements

Project requires test methods Color white, white or light yellow Take 50 g sample in a clean white porcelain dish, under natural light, observation its color, state, smell the smell Status granular, flaked or without visible impurities Inherent odor product smell, no odor

2.3 Physical indicators

Physical and chemical indicators should be consistent with the provisions of Table 2.

Table 2. Physical and chemical indicators

Item Index Test Method Loss on drying, w /% Cereal starch <= 15.0 GB/T 12087 other monomers starch <= 18.0 Potato starch <= 21.0 Total arsenic (As)/(mg/kg) <= 0.5 GB/T 5009.11 Lead (Pb)/(mg/kg) <= 1.0 GB 5009.12 Sulfur dioxide/(mg/kg) <= 30 GB/T 22427.13 Carboxy/(g/100g) <= 1.1 GB/T 20374 Appendix A Testing method A.1 Safety Tips Reagents The standard test methods used for toxic or corrosive, the operation should be careful! As should be immediately splashed on the skin Rinsed with water, severe cases should be treated immediately.

A.2 General Provisions Unless otherwise indicated in the analysis using only recognized as analytical reagents and GB/T 6682 stipulated three water. Test Methods Standard titration solution, impurities measured by standard solution, preparations and products, did not indicate when the other requirements, according to GB/T 601, GB/T 602 and the provisions of GB/T 603 of preparation; the solution when the solvent is not specified, refer to the aqueous solution.

A.3 Identification Test A.3.1 microscopy Gelatinized starch processing without holding oxide particle structure can be directly observed and verified starch particle shape, size and character through a microscope.

Under polarized light microscope, it can be observed the typical birefringence.

A.3.2 iodine staining 1 g of the sample was added 20 mL of water were suspended, several drops of iodine solution, the color should range from deep blue to reddish brown.

A.3.3 copper reduction A.3.3.1 formulated alkaline tartrate copper test solution A.3.3.1.1 Solution A. Copper Sulfate (CuSO4 · 5H2O) 34.66 g, should be no weathering or moisture absorption phenomenon, dissolved in water volume to 500 mL.

The solution was stored in a small sealed container.

A.3.3.1.2 Solution B. take potassium sodium tartrate (KNaC4H4O6 · 4H2O) 173 g sodium hydroxide 50 g, dissolved in water volume to 500 mL.

The solution was stored in a small container and alkali corrosion.

A.3.3.1.3 solutions A and B mixed in equal volumes, to obtain an alkaline tartrate copper test solution.

A.3.3.2 analysis step Weigh the sample 2.5 g, placed in a flask, 0.82 mol/L hydrochloric acid solution of 10 mL of water and 70 mL, mixing, boiling water bath back Stream 3 h, cooled. Take 0.5 mL solution was cooled, added 5 mL hot alkaline copper tartrate solution, a large amount of red precipitate.

A.3.4 Identification of oxidized starch (not suitable for low-grade oxidized potato starch) A.3.4.1 Principle Sodium hypochlorite oxidized starch contains certain carboxyl group, having anionic character. Dye capable of being positively charged, such as methylene blue staining.

A.3.4.2 Identification of 50 mg samples remain suspended in 25 mL concentration of 1% aqueous solution of methylene blue 5 min ~ 10 min, stirring occasionally. Decanted go After the supernatant off, washed with water and starch. If the sample is oxidized starch, sodium hypochlorite, microscopic examination will clearly show color. By measuring Test, oxidized starch can be distinguished from natural or acid-treated starch.