GB 29932-2013Food additive -- Acetylated starch adipate double (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 reagent type and amount.

a) adipic anhydride, not more than 0.l2% by mass of dry starch;

b) acetic anhydride, not more than 8.0% by mass of dry starch.

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 Acetyl/(g/100g) <= 2.5 Appendix A A.4 Appendix A Testing method A.1 Safety Tips Reagents The standard test methods used for toxic or corrosive, the operation should be careful! As splashed on the skin should stand that is 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 Pasting process without holding acetylated starch adipate double particle structure, can be directly observed through a microscope to identify the shape of the starch granules, Size and character. Under polarized light microscope, it can be observed the typical birefringence.

A.3.2 iodine staining the sample was 1 g 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 acetyl discrimination A.3.4.1 Principle Acetate is released from the saponification of acetylated starch out. After concentrated, with the calcium hydroxide were hot, acetate into acetone, propylene One with o-nitrobenzaldehyde effects appear blue.

A.3.4.2 Identification of About 10 g of sample is dispersed in 25 mL of water, then add 20 mL0.4 mol/L sodium hydroxide solution. Shake 1 h and filtered. filtrate an oven at 110 °C was evaporated, the residue was dissolved with a little water and transferred to test tubes. In the test tube was heated and calcium hydroxide.

If the sample is starch acetate, acetone will produce steam. Its vapor can by the use of 2 mol/L sodium hydroxide solution now with the ortho-nitrobenzene Formaldehyde saturated solution soaked through the paper turns blue. If 1 drop of hydrochloric acid solution 1 mol L/removal of the reagent original yellow, the blue the color will be more clear.

A.4 Determination of acetyl group A.4.1 principle of the method Starch contains acetyl groups under basic conditions (pH>=8.5) Easy saponification, so with excess alkali to saponification, and then titrated with standard hydrochloric acid Solution to the remaining base titration can be determined acetyl content.

A.4.2 Reagents and materials A.4.2.1 sodium hydroxide.

A.4.2.2 hydrochloric acid.

A.4.2.3 sodium hydroxide solution. c (NaOH) = 0.1 mol/L.

A.4.2.4 sodium hydroxide solution. c (NaOH) = 0.45 mol/L. Weigh 18 g of sodium hydroxide dissolved in 100 mL of carbon dioxide-free water in, shake, transferred to a 1000 mL volumetric flask, dilute to the mark with carbon dioxide-free water and shake.

A.4.2.5 hydrochloric acid standard titration solution. c (HCl) = 0.2 mol/L.

A.4.2.6 phenolphthalein indicator solution. 10 g/L.

A.4.3 Instruments and Equipment Mechanical oscillator.

A.4.4 Analysis step

Weigh 5g samples, accurate to 0.001 g, placed in 250 mL conical flask, 50 mL of water and 3 drops of phenolphthalein indicator solution, were mixed After leveling with sodium hydroxide solution (A.4.2.3) titrated to reddish, then add 25.0 mL of sodium hydroxide solution (A.4.2.4), the mechanical oscillations on is shaken vigorously 30 min for saponification.

Remove the stopper, rinse bottle with iodine bottle stopper and the bottle wall, which has been saponified containing excess alkali solution with hydrochloric acid standard titration solution Titration to the disappearance of the pink is the end, volume V1.

In 25.0 mL of sodium hydroxide solution (A.4.2.4) blank, with the volume of hydrochloric acid standard solution titration is V0.

A.4.5 Calculation Results Mass fraction w0 acetyl group, according to the formula (A.1) Calculated.

McVV

w (A.1)

Where.

V0-- hydrochloric acid standard titration solution volume consumed in the blank, in milliliters (mL);

V1-- hydrochloric acid standard titration solution consumed by the sample volume, in milliliters (mL);

C-- exact concentration of hydrochloric acid standard titration solution, expressed in moles per liter (mol/L);

Molar mass M-- acetyl group, units of grams per mole (g/mol) [M (C2H3O) = 43.03];

Quality m-- sample in grams (g);

1000-- conversion factor.