Test Milling - Chopin CD 2 Modo De Empleo

3.

Test milling

Instruction manual 
02/2017
Laboratory Mill CD 2
Milling is carried out using 600 g of durum wheat, which have been
cleaned in order to remove all foreign particles. By either damping
or drying, the moisture capacity of the grains is fixed to 16.5 or
17.5 % (see below).
Significant semolina production requires three following operations:
3.1 Conditioning the wheat
■ Cleaning
The grain must be carefully cleaned and all foreign grains (cereals
other than wheat and fodder plants), stones and metallic particles
removed.
Cleaning is done either by hand (spreading out the sample on a
0.50 x 0.50 m surface) or by an automatic cleaner such the Chopin
Technologies sample cleaner "Quatuor" or "NSP".
■ Conditioning to obtain correct moisture level
❏ The amount and the distribution of moisture in the grain are
extremely important in order to obtain good milling. Thus, it is
necessary to normalize moisture content at a fixed level by
damping, and to try to obtain conditions favouring the better yield of
semolina.
❏ The simplest method is the so-called "cold tempering" technic.
Time of tempering can vary as a function of aims or used technics.
For example:
- I.N.R.A. (Institute National of French Agronomical Research)
First 48 hours tempering period to increase moisture to 14.5 %
second damping to increase to 17.5 % with 25 min. tempering
period.
- Damping to increase to 16 % with 4 hours tempering period fol-
lowed by a second damping of 0.5 % 10 minutes before milling.
- First damping to increase to 16.5 % with 3-hours tempering period
followed by a second damping to 17.5 % 30 minutes before milling.
The table in appendix 1 shows the amount of water in ml to add to
500 g of grain varying in moisture content in order to bring the water
content to 16.5 or 17.5 %.
❏ The most common way of preparing wheat in order to obtain the
adequate moisture content is to put a sample in 2-litre air-tight flash
and shake manually for several minutes in order to completely
distribute the water previously added with a graduated tube. This
method which has not been standardized in detail appears much
too rough when we think of the importance of this preliminary test
milling phase.
GB
29