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Soluble Coffee
Spray
Drying | Agglomerated
Coffee | Freeze
Drying
We have a diverse range of blends developed
to suit tastes across various countries.
We have pure robusta, pure arabica and robusta
arabica mixes to ensure taste of Coffee
on one hand
We have developed various
coffee chicory mixes that afford an unbeatable
price to many mix manufacturers across the
world.
Spray
Drying
This method of drying
is preferred to freeze drying in some cases
because of its cost effectiveness, short drying
time, usefulness when dealing with such a
heat sensitive product, and the fine, rounded
particles it produces.
Spray drying produces spherical particles
of size roughly equal to 300 µm with
a density of 0.22 g/cm³ (ref 2). To achieve
this, nozzle atomisation is used. Various
ways of nozzle atomization can be used each
having its own advantages and disadvantages.
High speed rotating wheels operating at speeds
of about 20,000 rpm are able to process up
to 60,000 pounds (27 t) of solution per hour
(ref 3). The use of spray wheels requires
that the drying towers have a wide radius
to avoid the atomised droplets collecting
onto the drying chamber walls.
Typical Spray Drying
Characteristics
 |
Completed in 5-30
seconds (dependent on factors such as
heat, size of particle, and diameter
of chamber). |
|
Moisture content
change, IN = 75-85% OUT = 3-3.5%. |
|
Air Temperatures,
IN = 270 °C OUT = 110 °C. |
| Specifications
- Pure spray dried Instant coffee |
|
|
Moisture content |
3.5% maximum |
|
Total ash (% on dry basis) |
12.0% maximum |
|
Caffeine content (% on dry basis) |
2.80% minimum |
| Solubility
in boiling water |
dissolves
readily in 30
seconds with moderate stirring |
Solubility
in cold waterat
16 +/- 2 c.
|
soluble
with moderate
stirring in 3 minutes |
| colour
factor |
68-78 |
| bulk
density (gm/cc) |
0.216
- 0.264 |
| Sediments |
y |
| Fluidity |
38-42 |
| ph |
4.7
- 5.2 |
| Sieve
analysis |
fines
(below 100mesh)
should not be more than 22% |
Agglomerated
Coffee
Agglomerated coffee
is preferred by many customers on account
of its easy dissolution format. Our experience
from supplying agglomerated coffee across
the world has taught us that physical characteristics
like granule size & uniformity are as
important in granulated coffee as organoleptics
like taste, body & zing.
We are able to prepare
excellent quality golden and dark brown agglomerated
coffee as required by different markets.
| Specifications
- Pure spray dried Instant coffee |
|
|
Moisture content |
3.5% maximum |
|
Total ash (% on dry basis) |
12.0% maximum |
|
Caffeine content (% on dry basis) |
2.80% minimum |
| Solubility
in boiling water |
dissolves
readily in 30
seconds with moderate stirring |
Solubility
in cold waterat
16 +/- 2 c.
|
soluble
with moderate
stirring in 3 minutes |
| colour
factor |
50-60 |
| bulk
density (gm/cc) |
0.222
- 0.283 |
| Sediments |
y |
| Fluidity |
not
applicable |
| ph |
4.7
- 5.2 |
| Sieve
analysis |
90%
retains between 6
& 35 astm mesh
& 50% above 18astm mesh |
Freeze
Drying
We are glad to inform
that our new Freeze Dried Coffee plant will
commence its production from March, 2007.
The plant is being set-up with the latest
machineries having state-of-the-art technology
obtained from E & E, Germany.
The basic principle of
freeze drying in the process for producing
instant coffee is the removal of water by
sublimation.
Since the mass production
of instant coffee began in post-WWII America,
freeze drying has grown in popularity to
become a very common method. This is often
because although it is frequently more expensive
than other methods of drying it generally
results in a higher quality product.
The Freeze Drying
Process
Agglomerated wet coffee granules are frozen.
For instant coffee this is a very important
stage. Freezing too fast leads to large
ice crystals and a very porous product and
can also affect the colour of the coffee
granules.
Frozen coffee is placed
in the drying chamber, often on metal trays.
A vacuum is created within
the chamber. The strength of the vacuum
is critical in the speed of the drying and
therefore the quality of the product. Care
must be taken to produce a vacuum of suitable
strength.
The drying chamber is
warmed, most commonly by radiation but conduction
is used some plants and convection has been
proposed in some small pilot plants. A possible
problem with convection is uneven drying
rates within the chamber, which would give
an inferior product.
Condensation - the previously
frozen water in the coffee granules expands
to 107 its volume, the removal of this water
vapour from the chamber is vitally important,
making the condenser the most critical and
expensive components in a freeze drying
plant.
The freeze dried
granules are removed from the chamber and
packaged
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