Section 1 - Introduction to the Milling Process Flashcards
What adjectives describe early grinding
Short and severe
How many passes did grain go through in early grinding
once
Why are rollermills more efficient than stones
Grinding path through pair of rolls is shorter and produces less bran powder
Although several stages of rolling are necessary to produce the same total reduction, wheatfeed can be sifted out between each stage to minimise bran powder
What does wheat receipt involve
Weighing, sampling, testing, release
What happens at the wheat silo
segregation, blending, pre-cleaning
What does wheat prep involve
Cleaning, gristing, conditioning, de-branning
What does milling involve
Separations, control loops, testing and co-products
What happens to the finished products
blending, redressing, positive vetting
What happens with product handling
bulk and packaging
What is the milling process flow
wheat receipt, wheat silo, wheat prep, milling, finished products, product handling
What is the milling process designed to do
-open up each wheat grain and scrape off endosperm
-remove the branny particles from the endosperm
-grind the endosperm into flour
sift the ground stock in order to:
- Remove any oversized endosperm particles that need further grinding
- Extract bran and germ particles that have escaped the action of the purifiers
- Remove flour produced at each stage asap
What are the three main grinding operations
Break system, scratch system, reduction system
What does the break system do
Removes endosperm from the bran in large pieces, producing as little bran powder and actual flour as possible
What does the scratch system do
Removes any small pieces of bran and germ sticking to endosperm
What does the reduction system do
Grinds the endosperm into flour of the necessary fineness while controlling damage to the starch granules and with minimum abrasion to any germ or bran particles present
What separations are made with sifting
Scalping - Removal of large branny particles from break stock as they overtail coarse sifter covers
Grading - Grading of released endosperm in break system plansifters according to size
Dusting - Removal of flour from stock prior to purification and after bran finishers
Dressing - Sieving out of flour released on the reduction rolls to ensure remaining stocks are free of any flour prior to next grinding stage
What is purification
Process by which semolina and middlings released by the break and scratch rolls are treated in a purifier to remove any branny particles - Produces cleaner and purer stock to feed the reduction rolls and improve quality of flour produced
What information does a flow sheet provide
the source and destination of each stock in the mill
Convert to UK convention:
B1/B2, B3/B4, B5C, B5F,
Br.1, Br.2, Br.3, Br.4,
DBR1, DBR2,
DIV1, DIV2, DIV3, DIV4,
P1, P2, P3, P4,
C1/2A, C1/2B, C3, C4, C5/6, C7, C8/9, C10, C11
1/2BK, 3/4BK, 5BKC, 5BKF,
BF1, BF2, BF3, BF4
VS1, VS2
1/2MD, 3/4MD, 3MD, 4MD
CS, FS, 3S, MS
A/B, X1/X2, C, B2, D/E, F, G/H, J, K
