Twin Stream Flour Blending System
The separate milling of flours of different characteristics and the subsequent blending of
these flours to meet a customer specification offers many advantages to the miller.
Gravimetric flour blending is the most accurate and consistent means to do so and in
addition allows the precise addition of Minor and Micro ingredient inclusions.
Twin Stream by Satake applies an alternative concept to the operation of a flour milling
batch blending system. It enables customer requirements to be met "on demand" -
or a "just in time" basis - whether they be for several tanker loads or a small
batch for a special purpose.
Twin Stream has been devised to be used either as an integral part of a new flour silo
installation, or to integrate with an existing flour storage facility.
Twin Stream is the final link in a chain of developments by Satake, which enables
automation of the complete milling plant to be implemented.
The
Principle
A pair of self-contained receivers arranged on load cells and thus acting as dynamic
scales allow Major ingredients to be fed directly to the Twin Stream from the main flour
storage bins.
Minor and Micro ingredients are proportioned by weight in parallel with the twin
receiver/scales, prior to the discharge of all the ingredients into a horizontal mixer for
thorough blending.
The blended mix is, in turn, discharged into a hopper for metering into the conveying
system, which feeds all the final destination points.
Semi-Continuous Blending 
Maximum throughput capacities are maintained due to the virtually continuous flow of Major
ingredients, made possible by the use of two receiver/scales. Each is filled
alternatively, on a flip flop basis, so that overall batch cycle times can be reduced.
With a conventional single weigh hopper system, the discharge times from the weigh hopper,
the settling time for the individual and final weights, and the time to zero tare before
weighments would have to be added to the overall batch times.
Direct feeding into the receiver/scales enables great flexibility when choosing a location
for the blending plant. The feeds can come from a number of separated sources - new or
existing - which would be impractical with gravity fed conventional scales.
The weighing, proportioning and blending equipment for Twin Stream is compact and
comparatively light. It can be inserted into existing buildings or erected in its own
steel-framed clad structure.
Added Ingredients
A host of finished product specifications can be met for specialist uses by the addition
of permitted Minor and Micro ingredients.
Typically, Minor ingredients are in the range of up to 5 per cent of flour weight and
include such materials as gluten (dried protein), creta (calcium carbonate) and also acid
calcium phosphate and sodium bicarbonate for self raising flour.
The Micro ingredients fall in the range of zero to one-half per cent of flour weight and
can include individual ingredient weights of only a few grams. Typical Micro ingredients
are ascorbic acid, fungal amylase, benzoyl peroxide, vitamin mix and potassium bromate
(where permitted).
The accuracy of proportioning these small ingredients is of profound importance to the
characteristics and acceptability of the finished products. Conventional systems adding
them on stream in the mill can never approach this level of accuracy or reliability.
Micro Controls
At the heart of the Twin Stream system lies a powerful microcomputer. Its fully developed
software package can be readily adapted for each customer's requirements. In a dynamic
system, the microcomputer has fast scanning rates, with an inbuilt averaging routine to
register each scale increment. This speed - combined with a "teach and learn"
facility - where each source bin has its own "cut off" constant means that
inflight compensation reaches very high levels of accuracy.
Hardware
The Twin Stream uses hardware and operating system software which is based on
internationally available standard microcomputer components.
It is a multi-tasking, multi-user package operating on a real time basis, with the
capability of controlling not only the batching, but also the equipment immediately
up-stream and down-stream.
The control system can be supplied as a simple free-standing unit with a colour graphic
VDU and printer. It can also be expanded to have additional monitoring points and to
communicate with other plant process controls.
Rinsing Cycle
Certain finished products are sensitive to even the slightest contamination from a
previous batch. For these flours, Twin Stream automatically inserts a "rinsing"
cycle prior to the start of a new batch, for example when a white flour follows a brown
flour.
So that no material is wasted, this rinse cycle flushes out the system with a part batch
of flour that is then redirected to a storage bin for later blending into an appropriate
product.
The Benefits
The Satake Twin Stream is a cost effective flour blending system. Its application may lead
to a more profitable flour milling operation and provide a good return on investment.
Using Twin Stream blending, it is possible to organise the whole operation of a milling
plant on an "on demand" or "just in time" basis. The benefits of
operating in this way include:
· longer production runs for the milling unit(s)
· better milling performance
· lower stock levels of finished products
· lower costs gristing
· opportunities for manless plant operation
· better consistency in the final products
· quicker response to market demands
· greater customer satisfaction
Menus and Recipes
The Twin Stream system is essentially multi-task and multi-user menu driven and is
immediately responsible to customer demand information.
A typical installation will hold up to 50 formulations or recipes, each using up to 50
separate ingredients. Formulations can be altered at any time, but only by authorised
persons with full password protection.
Tasks and Manless Operations
A job queue of up to 20 tasks is held to enable extended periods of unsupervised
operation. The priority listing of these tasks can be amended manually at any time by the
operator, and it will be altered automatically according to the availability of
ingredients and destination points at any particular moment.
The task sheet or job queue can be set up during the daylight period and the plant will
continue to work its way through the priority listing overnight, unattended.
All these parameters can be increased by the simple addition of modules of hardware and
software.
Running Waste Eliminated
Storage bins can be completely emptied using Twin Stream, leaving no residues, thanks to
its ability to produce part batches.
Similarly, since Twin Stream does not require service bins to feed the receiver/scales,
there are no residues to handle here.
All tasks are automatically divided into a multiple of batches, which accumulate to
produce the precise quantity of finished product demanded.
Consistency and control of product
Most bakery processes are continuous and very finely controlled. It is, therefore, of
importance that the dry ingredients - the flour and its additives - are reliably
consistent.
In a batching system, errors are instantly detected. Corrections can then be initiated to
eliminate risks of off-grade finished products.
The accuracy of the Twin Stream's weighing and proportioning enables formulations to be
precise, thus ensuring consistency whilst eliminating the giving away of costly
ingredients.
A regular printout of all materials used and quantities of flours made provides an
accurate record of all production, on a daily, weekly and monthly basis.
The Capabilities
White Flours
A full range of specification white flours, blended "on demand" in the Twin
Stream system from a range of base flours, gluten, plus Minor and Micro improving
ingredients.
Brown Flours
Produced by adding varying proportions of bran and wheatgerm to various base flours in the
Twin Stream system. Wheatflakes and other similar ingredients can easily be included in
the recipes.
Special Mixes
For self raising, pizza and other speciality flours, the Twin Stream blending system lends
itself to the production of small orders for special mixes of Major, Minor and Micro
ingredients.
