GB/T 10463-2024Maize flour (English PDF)

3 Terms and definitions

The terms defined in GB/T 22515 and GB/T 26631 apply, together with four terms defined here.

3.1 Degermed maize flour: the powdered product made from maize or maize grits through cleaning, dehulling, degerming and grinding.

3.2 Whole maize flour: the powdered product made from maize by direct grinding after cleaning.

3.3 Coarse maize flour: maize flour that passes entirely through a CQ10 sieve and of which not less than 90 percent is retained on a CQ27 sieve.

3.4 Fine maize flour: maize flour that passes entirely through a CQ10 sieve and of which less than 90 percent is retained on a CQ27 sieve.

4 Classification

Maize flour is classified by processing route and fineness into four classes: degermed coarse maize flour, made from degermed maize or maize grits by the degermed maize flour process and meeting the coarse fineness; degermed fine maize flour, made from the same raw materials by the same process and meeting the fine fineness; whole coarse maize flour, made from maize by the whole maize flour process and meeting the coarse fineness; and whole fine maize flour, made from maize by the whole maize flour process and meeting the fine fineness.

5 Raw material requirements

Maize shall comply with GB 1353 and maize grits with GB/T 22496. The water used shall comply with GB 5749.

6 Quality requirements

6.1 The quality indicators are given in Table 1, whose four columns are the four classes: degermed coarse maize flour, degermed fine maize flour, whole coarse maize flour and whole fine maize flour. Fineness repeats the class definitions: coarse flours pass entirely through a CQ10 sieve with not less than 90 percent retained on a CQ27 sieve, fine flours pass entirely through a CQ10 sieve with less than 90 percent retained on a CQ27 sieve. Ash content on a dry basis is not more than 1.0 percent for both degermed flours and not more than 3.0 percent for both whole flours. Sand content is not more than 0.02 percent, magnetic metal not more than 0.003 g/kg and moisture not more than 14.5 percent, in each case for all four classes. Colour, odour and taste shall be normal, and the appearance shall be a dry, loose powder or fine granules free of lumps. Crude fat on a dry basis is not more than 2.0 percent for both degermed flours and not more than 5.0 percent for both whole flours. The fatty acid value on a dry basis, expressed as potassium hydroxide, is not more than 60 mg/100 g for both degermed flours and not more than 80 mg/100 g for both whole flours.

6.2 The requirement for net content refers to the Measures for the Metrological Supervision and Administration of Prepackaged Commodities.

7 Test methods

Sampling and sample division follow GB/T 5491. Fineness follows GB/T 5507, ash content GB 5009.4, sand content GB/T 5508 and magnetic metal GB/T 5509. Moisture follows GB 5009.3 or GB/T 5497, GB 5009.3 being the arbitration method. Colour and odour follow GB/T 5492. Taste is judged by mixing the sample with clean water until no dry flour remains, pouring it into a pan of boiling water and cooking it into a maize porridge for tasting. Appearance is judged by placing the sample in a clean white porcelain dish and observing it by eye in ample, soft light. Crude fat follows GB 5009.6, the fatty acid value follows Annex A of GB/T 20570-2015 and the net content follows JJF 1070.

8 Inspection rules

8.1 The general rules of inspection follow GB/T 5490.

8.2 The factory inspection items are fineness, ash content, sand content, magnetic metal, moisture, colour, odour, taste and appearance.

8.3 One batch is the same product processed from the same raw material with the same process, on the same equipment and in the same shift.

8.4 A product in which one quality indicator fails on inspection is judged not to comply with this document.

9 Labelling

The product name and class shall be marked with the name and class laid down in this document, and the specification, quantity, date of production, and name and address of the producing enterprise shall also be stated.

10 Packaging, storage and transport

10.1 Packaging shall comply with GB/T 17109. The package shall be tidy inside and out, and the outer package shall be proof against water, dust and contamination.

10.2 Storage shall guard against a rise in grain temperature, against damp and against pests. The product shall not be stored together with other materials that carry an odour. During storage the bags shall be turned and the stacks rebuilt in good time according to the weather conditions.

10.3 The product shall not be transported together with toxic, odorous, corrosive or otherwise contaminating goods.