2 - Flour Grades Flashcards
(15 cards)
Which 2 characteristics apply to flour produced on the break system
May contain bran
Produced by attrition
Which characteristics apply to flour produced on the head reduction passages
High proportions of endosperm
Lower protein
Which 2 trends are seen in machine flours as we go from head end to tail end
Ash content/colour increases
Protein quantity increases
Protein quality decreases
starch damage/ water absorption increases
In a 3 conveyor mill, where do the conveyors go
1 - top grade, head reduction
2 - middle grade, 1-2 breaks and middle reduction
3 - low grade - 4 and 5 breaks and tail end flours
What flours are included in a straight run flour
All machine flours
What flour is excluded from patent flour
Tail end flour
Describe why and how machine flours vary in quality
Different areas of the wheat grain
Head end reduction has a high proportion of starch endosperm from the centre of the grain
Further down progressively more outer layers of endosperm branny material
Break system - flours from break passages bran content increases from 1st break onwards
Protein quantity is higher in the outer layers than the centre, so tail end of reduction system has a higher protein quantity
Protein quality is lower in lower grade flours despite having a higher quantity
On an ash curve table, if the ash content is to be less than 0.53, which streams are excluded
H, J, K
If the finished product is to have an ash content less than 0.53, what percetnage of the mill feed is included in the flour
76.5
If the finished product is to have an ash content less than 0.53, what percentage of the mill feed would be directed to the low grade conveyor
3.2%
A patents flour contains the first 9 streams listed, what is the cumulative ash content of this patents flour
0.456
How to generate a cumulative ash curve
- Collect samples from every machine flour stream feeding the finished product conveyors and measure feed rate and determine ash content
- For each stream, work out quantity as a percentage of the mill feed
- Order the streams in ascending order of ash content
- Work out the cumulative % mill feed by summing % mill feed of each stream up to that point
- Work out the cumulative ash by working out a weighted average of the combined streams
- Plot the cumulative ash against the cumulative % mill feed
What 2 statements best define quality from the customers perspective
Consistent
Fit for purpose
What parameters are most important to the miller
Ash, protein, starch damage, water absorption
What may cause an ash curve to vary
Grist
Mill setting
Milling conditions
General state of plant
