CEREAL TECHNOLOGY – grain cleaning & milling

Assoc. Prof. Marie Hrušková, PhD

CEREAL TECHNOLOGY – flour processing

Main parts of flour processing:
• grain mass cleaning
• grain milling and sieving
• commercial flours mixing
• quality standardisation

CEREAL TECHNOLOGY – grain cleaning

Main objectives of grain cleaning:
• to separate the grain from organic and mineral impurities, feromagnetic components
• to remove parts of bran from grain endosperm
• to moisturing the grain mass for reduce adhesion between bran and endosperm
• to standardisation of grain moisture before milling

Wheat cleanners:

For organic impurities

For mineral impurities

Bran removing machine

Water content regulation

– basic procedure before milling

Moistening machine Automatic regulation of moisture level before and after moistening

CEREAL TECHNOLOGY – moistening before the milling

Moisture level recommended for different wheat

Wheat type                                          Moisture %
Extremally hard (Manit., dur.)   16,5 – 17,5
Americ. Bakery hard (HRW)       15,5 – 16,5
American (Austral.) soft               15,5 – 16,0
Traditional Soft European            15,0 – 16,0

CEREAL TECHNOLOGY – milling

Two main objectives of wheat milling:
• to separate endosperm of the grain from bran and germ
• to reduce dimensions of endosperm particles for fine flour particles
Fine flour – particles passing through the sieve with the rectangular apertures 140 μm in side

Middle Europe – mainly Czech
Austria – also coarser flours

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