Technological process of black pepper

 In order for black pepper to reach consumers and be used in daily meals, producers must go through the following steps.

Principle of black pepper processing

Raw black pepper is put into an underground feeder and transferred to the impurity screen through a bucket. The impurity sieve works based on the aerodynamic principle, the separation principle of weight, and the separation principle of volume. 

• Products obtained: clean black pepper meeting ASTA standards
• Capacity: 4,000 tons/year
• Main activities in black pepper processing

Clean black pepper

Impurities are removed from raw black pepper before it is placed in an underground feeder. About 90% of impurities mixed in pepper can be separated by impurities screening, including impurities smaller than pepper, impurities larger than pepper, and impurities lighter than pepper (including dust). The impurity sieve also has the effect of separating iron and steel combined in the raw materials because it has a magnetic component connected. After passing through the impurity screen, raw black pepper has a size of 2.5 mm to 6.5 mm.

Sort by size

After being separated from impurities, black pepper, different from standardized white pepper is transferred to a sorting sieve by a bucket. The sorting sieve includes 3 sieves with sizes: 4.5mm, 4.9mm, and 5.5mm. Pepper after cleaning is divided into 4 product lines:

• Seeds are sized from F2.5 mm – F4.5mm
• Seeds have sizes from F4.5 mm – F4.9mm
• Seeds are sized from F4.9mm – F5.5mm
• And the particle size is larger than F5.5mm

Size-graded black pepper is placed in 4 containers. From these 4 containers, we can mix nuts according to the requirements of finished products for export or further processing.

Separation of stones

Black pepper before entering the stone separator machine is still mixed with grains of the same size as black pepper. The gravel separator works on the principle of difference in density of black pepper particles of the same size. Lighter pepper will be lifted by a stream of air to form a flow parallel to the sieve to flow out. Meanwhile, heavier gravel particles will fall to collide with the edges of the mesh groove and jump backwards to escape.

Aerodynamic classification

Black pepper after leaving the stone separation machine still has firm and porous black pepper that are not removed due to the same size. The black pepper is fed into an aerodynamic classifier called a Catador. In this device there is a vertical flow of air from bottom to top. Thus, the porous and light pepper particles will be lifted and released, while the firm seeds will be suspended and separated in a different way. The air flow in the catador is adjusted according to the quality of the pepper.

Spiral density classification

Black pepper after the process of cleaning, sorting by size, separating gravel and classifying by aerodynamics is still different in shape: dented or round or mixed with black pepper stalks.

The spiral shape sorter is composed of baffles that spiral around a vertical axis. The black pepper mixture of deformed and round black pepper is loaded into the upper mouth of the sorter.

Because the granules spiral down under the action of gravity. The circular particles rotate so their acceleration increases gradually to a point where they rotate according to the inclination of the baffle at the outer edge and are separated, while the deformed particles when falling freely on the spiral chute are subjected to a higher frictional force than the speed. flow rate is not equal to that of round beads. Thus the deformed particles flow closer to the axis of the helical machine and are brought out.

Washing and microbiological treatment with steam

To eliminate the most harmful microorganisms, especially salmonella, people use steam with a pressure of 2÷3kg/cm2 with a temperature of 1200C – 1400C to spray on black pepper in the shortest time (about 20 – 40 degrees Celsius).

In the process of absorbing hot steam, the black pepper is conveyed through the water extraction drum before passing through the drying system.

Drying

The drying system uses two continuous stages including two drying towers: the input layer and the drying layer. The black pepper drying capacity is adjusted to match the moisture content of the raw materials for high efficiency thanks to the star fruit discharge screw system. To ensure the aroma of black pepper, the heating system uses a gas burner with an automatic gas burner to ensure the system of occupational safety and fire.

Cooling after drying and sorting

After drying, the black pepper is put into a cooling barrel and again the black pepper is passed through the catador to separate impurities including dust and black pepper shells arising from the drying process. Then the black pepper is put into the spiral shape sorter (2nd time).

Automatic weighing scale

Finished black pepper is put into a container for storage or put into an automatic weighing system to measure as required.

Quantitative balance is automatically controlled by an electronic system with a digital display from 30-60kg, the allowable error is ±45g/50kg, capacity 200bags/hour.