Thanks to technological breakthroughs, instant coffee manufacturing has evolved into one of the most seamless processes, with industrial manufacturers guaranteeing greater taste and a rich aroma.
However, what does it take to generate soluble coffee powder from raw coffee cherries? This article takes you through the processes and steps undertaken by coffee processors to generate flavorful instant coffee powder with the required particle size and moisture content.
Instant Coffee Powder Making Process in 10 Steps
Step 1: Selecting and Roasting Coffee Beans
Commercial instant coffee powder manufacturers place a lot of emphasis on the quality of coffee beans used. Remember, it is the coffee beans that will determine the quality of your of the finished powder as well as the flow of downstream processes. You can choose either Arabica or Robusta coffee beans.
- Arabica Coffee Beans: They are revered by manufacturers and coffee processors looking to produce soluble coffee powder with a mildly acidic flavor. They are comparatively smoother and boast a richer aroma.
- Robusta Coffee Beans: Robusta beans are renowned for their relatively greater caffeine content, giving them a richer taste. They are preferred by commercial manufacturers prioritizing a stronger taste.
The coffee beans are then rigorously cleaned before being subjected to temperatures ranging from 180°C to 240°C. This carries on for approximately 10-20 minutes or until the right roast profile is achieved. Roasting coffee beans initiates caramelization amongst other chemical reactions, ultimately determining the color, flavor, and aroma of the finished coffee powder.
Step 2: Grinding the Roasted Coffee
The roasted coffee beans are subsequently passed through an industrial fluid bed granulator. With these granulators, you can produce smaller particles measuring between 1.5 mm and 3.0 mm. This fine particle size guarantees a higher particle surface area, which is essential for managing hydrodynamic flow.
You must put more emphasis on the particle size since smaller particles are likely to increase the risk of pressure drop, which causes compaction. Coarser coffee bean particles, in contrast, increase the risk of under-extraction by impeding mass transfer kinetics.
Step 3: Extracting Soluble Coffee Solids
The ground coffee is then mixed with hot water and heated and pressurized to generate a concentrated liquid extract. During extraction, the soluble solids in the roasted and ground coffee beans are removed. Industrial manufacturers rely on specialized multi-stage machines to extract the soluble solids without diluting the flavor and aroma of the instant coffee powder.
This boosts the powdered coffee yields, leaving the processors with more finished powder. The applied pressure and temperature are greatly controlled to maximize the recovery of soluble solids, consequently improving the yield, retaining flavor, and widening the manufacturer’s profit margin.
Step 4: Filtering and Clarifying the Coffee Extract
The coffee extract collected after grinding and extraction is subsequently filtered using specialized industrial filtration systems, which target suspended solids. Coffee processors generally utilize mesh screens and centrifugal separators to alienate unwanted elements such as oils and cell fragments from the extracted coffee.
Through these processes, you can improve both flavor and color of finished coffee powder therefore, you must prioritize filtering and clarification.
Step 5: Concentrating the Coffee Extract
The filtered and clarified coffee extract is then driven into a vacuum evaporator to boost its concentration. The coffee extract departing the industrial filters boasts a concentration of approximately 20-28%, and this step generally drives up the total dissolved solids concentration to approximately 40-50%.
Concentrating the coffee extract also drives up the dryer’s throughput by increasing the amount of solid coffee that passes through the coffee dryer per minute. The increased TDS also translates into faster evaporation, ultimately driving down the energy consumption for commercial soluble coffee manufacturers.
Step 6: Recovering Coffee Aroma
As the ground coffee is brewed and concentrated, some essential aromatic compounds may break free, and this can lead to the generation of low-quality instant coffee powder. To manufacture premium-quality soluble coffee powder, industrial processors integrate an aroma recovery step, consequently giving the finished powder its natural fragrance and flavor.
This step involves the use of advanced technologies such as steam distillation and vacuum stripping. These technologies simply entrap the aromatic compounds before reincorporating them back after brewing and coffee extract concentration.
Step 7: Converting Coffee Extract into Powder
After reincorporating essential aromatic compounds in the concentrated coffee extract, drying is initiated to generate shelf-stable instant coffee powder ready for the market.
Here, you can adopt these two popular processes:
· Spray Drying Instant Coffee
Spray drying is without a doubt the most manufacturers’ chosen coffee drying technology. It is revered for its unrivalled instant coffee powder drying speed and overall cost-effectiveness. It requires the use of instant coffee spray dryers specialized to handle heat-sensitive materials.
It is driven into a drying chamber or tower from the top, and as it percolates downwards, it is subjected to controlled hot air under pressure moving upwards. This preserves the essential aromatic compounds reincorporated in coffee extract, consequently guaranteeing consumers an original taste and flavor.
Benefits of Spray Drying Instant Coffee Powder
- Comparatively quicker (3 to 20 seconds).
- Generates smoother instant coffee powder.
- Efficient energy consumption.
- Guarantees consistent powder quality.
- Guarantees highly soluble coffee powder.
· Freeze-Drying Instant Coffee
Freeze-drying is not as popular as spray-drying amongst coffee processors and industrial manufacturers. It is, however, popular for the quality of instant coffee powder it generates. Freeze-drying involves subjecting the concentrated coffee extract to temperatures as low as -40°C in a vacuum chamber. This prompts the water harbored by the coffee extract to sublimate, ultimately generating highly soluble instant coffee powder.
Benefits of Free-Drying Instant Coffee Powder
- Generates instant coffee powder with a more striking or appealing color.
- Preserves the nutritional profile and flavor of the coffee better.
- Near-instant dissolving.
- Preserves the aroma and taste better.
| Factors to Consider | Spray Drying Instant Coffee | Freeze Drying Instant Coffee |
| Drying Principle | Utilizes a stream of hot air to evaporate the water in concentrated coffee extracts. | Subjects the concentrated coffee extract to low temperatures, prompting sublimation. |
| Processing Speed | Extremely fast, lasting between 3 and 20 seconds. | Comparatively slower and could take up to a few hours. |
| Production Cost | Typically, pocket-friendly. | Relatively more expensive. |
| Powder Structure | Generates spherical coffee particles with a uniform particle size. | Generates relatively bigger instant coffee powder particles shaped like crystals. |
| Aroma Retention | Moderate aroma. | Rich and authentic aroma. |
| Large Volume Production | Ideal for large-scale production due to the faster drying speed. | Takes time, making it less suitable for large-scale instant coffee powder manufacturing. |
Step 8: Agglomerating the Instant Coffee
The spray-dried or free-dried instant coffee powder is then injected into a heated chamber, where it is steam-heated, giving the particles a sticky feel. This also increases the size of the coffee powder particles whilst forming uneven coffee clusters. The agglomerated coffee granules are consequently subjected to hot air, making them dry and dust-free.
Step 9: Testing Instant Coffee Powder Quality
To outwit rival brands, most instant coffee powder processors employ quality control after every step is concluded.
You should start quality control by picking the right coffee beans and end with double-checking the packaging container or sachet used.
The powdered coffee is, however, taken through multiple tasting panels and in some instances, tested in the laboratory to guarantee an authentic flavor and consumer safety.
Step 10: Packaging and Storage
The dried and agglomerated instant coffee powder is subsequently packaged before it absorbs moisture. Moisture absorption tends to clump the coffee, consequently diluting its quality and flavor. Most manufacturers prefer using moisture-proof sachets or lidded glass jars to guarantee a longer shelf life.
FAQs
What affects instant coffee powder quality during spray drying?
Spray drying is the preferred coffee drying technology. However, manufacturers risk diluting the coffee’s flavor and quality if the applied heat is excessive or insufficient.
Why is coffee difficult to spray dry?
Spray drying instant coffee powder is considerably difficult because it necessitates greater control over the drying time and heating medium. Overheating the coffee extract risks extracting key aromatic compounds from the coffee, while underheating risks generating sticky coffee granules.
What temperature is used to spray-dry coffee?
Spray-dried instant coffee powder is typically processed in specialized drying chambers with hot inlet air set at a temperature of 150°C to 250°C. The outlet air is set at 80°C to 110°C, and this guarantees optimal flavor and aroma preservation.
Why does coffee powder stick to the spray dryer?
The coffee extract driven into the spray dryer drying chamber may cling to the walls of the chamber or tower if the inlet and outlet hot air temperatures are set too low. This is because the resulting granules are left with a high moisture content.
Is instant coffee powder similar to regular coffee powder?
No. Instant coffee powder is essentially pre-brewed coffee that comes packaged in sachets or food-grade jars ready for immediate use. Regular coffee powder, conversely, requires brewing and filtration before use.
Final Thoughts
If you want to produce quality coffee powder, then you must control every process – from coffee bean selection, grinding, spray drying to packaging. More importantly, you must choose the right equipment that can guarantee high-quality instant coffee while maximizing operational efficiency.
For custom instant coffee powder manufacturing, Pilotech will help you to get a customized solution for your product processes – Get a quote now.