Carbohydrates: milling Flashcards
What are the main stages of wheat milling?
Removing contaminants.
Conditioning the wheat.
The milling process.
How are contaminants removed during wheat milling?
Field: Threshing and winnowing.
Screenroom: Uses sifters, magnets, aspirators, inclined screens, and disc separators to remove stones, metal, and other impurities.
What is the purpose of conditioning wheat?
To control moisture content (14-17.5%).
Toughens the bran and softens the endosperm for easier separation.
Saves energy during rolling.
What issues can arise from wheat conditioning?
Increases bacteria, yeast, and mold counts.
Requires specific moisture levels:
Hard wheat: 16.5% moisture, 10-36 hours.
Soft wheat: 15-15.5% moisture, 6-18 hours.
What happens during the breaking stage of milling?
Grain is broken into smaller particles containing bran and endosperm.
Semolina is separated using plansifters and purifiers.
What factors influence flour quality before processing?
Wheat variety.
Presence of impurities.
Drying and storage conditions.
What are the main outputs of the milling process?
Semolina
Bran
Flour
Branny endosperm
What factors influence flour quality during processing?
Condition and settings of roller mills.
Atmospheric conditions.
Extraction rate.
What are the protein levels of different flour types?
White Bread Flour: 12-14%.
Wholemeal Flour: ~13%.
Cake Flour: 8-12%.
Plain Flour: ~10%.
What is the purpose of debranning?
Improves bread quality, texture, and shelf life.
Enhances nutrition by including the aleurone layer.
Removes surface-borne contaminants.
How is starch damage assessed in flour?
Using the Ceralpha method with a spectrophotometer at 400 nm.
What is added to flour during finishing?
alcium, iron, thiamine (Vitamin B1), and niacin (Vitamin B3).
