Coffee Beans
Table of Contents

Coffee is a famous commodity in the whole world. Oil is on first number and Coffee is on the second number.

Different products normally used to import, export like rice, cotton, sugar, and corn etc. 90% coffee production, refining, grading, and processing takes place in developing countries like Brazil, Colombia, and Vietnam. Coffee is included in expensive products.

According to the demand and finding in the market, coffee bean sorter (optical color sorter) really helps to screen Arabica and Robusta coffee beans.

By removing all the defected and discolor beans from the raw material you can get fine quality coffee with the highest food quality assurance.

All the rocky material, sticks and stones screen out from the material to get quality output.

Chapter 1: What is a Coffee Color Sorter?

Sortex Tea Optical Sorter

Graphic: Sortex Optical Sorters For Tea Sorting

As you know sorting is the process of screening defected material from the raw material.

Coffee color sorter is machinery based on CCD optical sensor used for sorting Arabica coffee beans and Robusta coffee beans.

The most interesting thing in coffee beans sorter it has monochromatic and bi-chromatic both options to detect different colors and remove for the fine quality.

As you know coffee beans are of different colors and types like red beans, dark green beans, black beans, brown beans, and most non-toxic bleached beans.

Coffee Color Sorter, also called Coffee bean color sorter, helps to separate all unwanted beans color from the raw material without any toxic process.

If you want to know how coffee color sorter is more efficiently screen out the products keep reading this chapter:

The automatic sorting machine with high definition CCD camera helps to scan the material 6000 times in one second and get high-resolution images of defected and approved beans.

You cannot assume even this is not controlled by any human it’s a total computerized system which regulates automatic collaboration and checking.

Normally coffee bean color sorter follows the pre-stored algorithms to process.

Types of Coffee bean sorting machine

There are three types of bean sorting machine.

  • Automatic coffee bean sorting machine

It regulates all the procedure automatically from the start till end.

Just put coffee beans into the bean sorting machinery and get the fine quality yield without any work.

  • Manual coffee bean sorting machine

In the manual sorting machine you need to operate the machinery by yourself.

Even you need to follow all the steps from the operational manual you get with your sorting machinery.

You need to use your touch panel carefully to operate and adjust all the parts according to the manual book.

  • Semi-automatic bean sorting machine

As you read above about automatic and manual bean sorting machine, this is the middle version of both types of machinery.

In this machine, you are allowed to operate by yourself but this gives very convenient user interface to operate and some of the options are automatic.

Chapter 2: Why Sorting Machines in Coffee Processing?

First, we need to clear one thing coffee beans are dry grains which required to process to make it’s quality better.

We have two options to remove dry skin from the coffee beans dry milling and wet milling.

First of all dry milling helps to remove dry crumbly skin of the beans by using generally bean sorting machines.

Secondly sort the coffee beans according to the size and density of coffee beans also removing sticks, stones, nails, and debris from the coffee and removing the particles which are mixed during the drying process.

Normally bean color sorter uses an air compressor to sort the beans in a way heavy particles remain close and the light particles go on a farther place.

Now, these days coffee bean color sorter used gravity separator it shakes the beans and separate heavy and light beans on one side.

Sorting by color is a very critical process, visual light source help to detect the different colors of beans and sort.

2.1 Coffee Bean Grade

The first question comes in mind what is coffee bean grade actually.

Graphic: Kona Coffee Bean

Some time we say the size of coffee beans is called grades because there is a general relation between the size and quality of the coffee beans.

Grade term is really confusing in the coffee industry, in some countries grades referred to hard beans and soft beans.

But this is the concept coffee beans with larger size is high quality and with smaller size are of low quality.

Coffee bean color sorter helps to screen the coffee beans according to the size to get perfect quality yield.

Different people research and collect data for the grading of coffee beans according to that:

Grade 1  In grade 1 you cannot find any defect in coffee beans.

It is sorted by 5% above the screen and 5% below screen also check the different attributes to prove it in grade 1 like toxic or nontoxic, taste, and aroma etc. most important moisture level is 9-13%

Grade 2  This grade is approximately the same as above. Full defects found 0-8 according to any attribute.

These are called premium grade coffee beans.

 Grade 3  These beans are called exchange grade coffee beans 9-23 full defects found in this grade.

Grade 4  These beans are known as standard coffee beans with 24-86 full defects.

Grade 5  These are called low quality off grade coffee beans with 86 full defects.

2.2 How to determine the quality of coffee bean color

Do you know the color of the coffee bean is a real factor to determine the taste of the coffee?

If no then continue reading;

Before roasting of coffee beans, the color of coffee is green with a very good smell but have no taste.

The processing on the coffee beans makes it aromatic and flavorful.

Moisture content

There is no fixed ratio of moisture in all coffee beans; normally 11% is a good percentage.

Keep one thing in your mind if your coffee beans exceeded from 12.5% moisture then it never allowed importing at any condition.

Appearance defects

Have a look at different defects of coffee beans:

  • Blackish
  • Blotchy
  • Antestia
  • Crushed
  • Diseased
  • Elephant beans
  • Faded
  • Foxy
  • Moldy
  • Paled
  • Ragged
  • Shell
  • Stinker
  • Under-dried

There are different defects which caused due to carelessness in processing, less maintenance of moisture content, discolor and physical defects.

Any type of defect must influence the quality of beans lets read all defects in detail and get how much coffee bean color sorter is important to improve the quality of beans.

§  Blackish

Black or dark color beans which are damaged due to immature harvesting or natural fall of cherries from the trees.

Some time due to exposure to heat and water.

If coffee beans are unroasted, more than 25% black, deep blue and dark brown can be considered black beans.

§  Blotchy

If coffee beans have some yellowish and whitish irregular patches it is called Blotchy. This is due to the uneven drying process.

§  Crushed

Coffee beans are crushed due to unsmooth pulping process or maybe it occurs during separation of beans from the husk.

§  Diseased

There are many diseases which damage plants especially coffee plants like fungus, Coffee Leaf Rust and Coffee Berry Disease.

§  Elephant beans

The group of two or more clustered beans which grow together and locked with each other is called “elephant beans” or “ears”.

§  Faded

Coffee beans which lost color, size or any other property due to any environmental, processing like bleached and soapy coffee beans.

§  Foxy

If you are careless during the drying process, washing process, fermentation or harvesting it can be brown coffee beans.

§  Paled

Due to drought or immature harvesting coffee beans looks pale and dehydrated.

§  Ragged

Drought effect beans and immature harvested fruit looks ragged in appearance.

§  Shell

This is the defect of coffee beans which occurs commonly, a cavity or a shell is produced around the beans. For example Black beans, stones, and stick which take the quality of beans to the lesser grade.

§  Stinker

Stinker is the defect but not regarding the shape and color it destroys the taste of coffee beans.

§  Under-dried

Coffee Beans less than 12.5% of moisture content lie in under dried condition. The normal ratio of moisture content is 10% to 12%.

Insects’ pest damage

Sometimes pests damage the crops, coffee beans can be affected by the pests.

2.3 Two Coffee Bean Processing Methods

There are different coffee bean processing methods by which we can process different types of material like rice, grains coffee beans and tea.

1) Unwashed or dry process

We can say it’s a dry process or natural process. It’s an old method to process coffee which was used before a hundred years.

The first step in this process is to take coffee cherries and washed them.

Let leave them to dry under the sun, once the cherries dried green seeds removed from the dried fruit after the fermentation process.

This process is very common, no additional skill is required to perform this process and it is globally used because of its a low budget process.

2) The washed or wet process

Do you know washed coffee is also called wet process?


Keep focus and learn washed coffee is a wet process in which the coffee cherry fleshed by a machine.

Then what?

It’s a surprise; outer layer of the skin is removed, as layer removed coffee beans going to ferment in water for about 2 to 3 days. After the coffee beans fermented now you are able to wash the coffee beans after it has released a smell (aroma).

No doubt it’s proved washed or wet process helps to make the highest quality coffee, however, it requires proper skill to process.

But also you need to keep in your mind this process is quite expensive as compared to other processes.

There are two ways to process the coffee beans in the wt method:

Ferment method of coffee beans sorting

In this procedure pulp is broken down by microorganisms in way cellulose is broken down to release the coffee beans.  On the next step, cherries need to wash to get separate from coffee beans.

Machine assisted wet processing

In this method, cherries are automatically clean and polish with scrubbing until the coffee beans are released.

Next step of machine-based wet processing is the separation of coffee beans from cherries and the last step is to be dried.

Chapter 3:  Types of Coffee Color Sorter

There are different types of color sorting machines which help to sort raw material into fine particles.

Optical Color Sorter

Optical color sorter some time called digital color sorter.

It’s a very intelligent sorting machine with high-resolution CCD cameras and ejectors to sort coffee beans.

The best feature of the optical color sorter is, it helps to protect your food according to safety & quality rules to maximize the yield.

Different types of sensors used in optical color sorter by which optical sorting machine identify the difference between color, size, and objects.

Coffee color sorter makes the precise comparison to grade different types of material and define select or reject according to the specific criteria.

Now a question comes in every person’s mind what’s the benefit of using optical coffee bean color sorter.

Optical sorter helps to improve the quality of food items according to the safety standards it also helps to improve throughput and reduce the labor cost.

The people who demand the highest quality optical sorter machine is best suitable for them.

  Components of Optical Sorters

Normally there are four components helps to work in optical sorting machines:

  1. The feed system
  2. Software for processing
  3. Sensors
  4. Separation system

Feed system helps to spread grains evenly to present in front of the optical system with uniform velocity.

Software used to process all grainy items to find faulty items with the help of cameras and sensors. It’s an electric sorting machine process the items according to food quality standards.

On the final step processing system make a comparison and classify objects in the separation system.

Laser Color Sorter

There are different types of sorting machines available in market laser color sorter is very efficient color sorter precisely detect and remove foreign material.

The most important feature of this machine is the inspection of food items in the air.

What do you mean by food items in the air?

Laser sorting machines classify the grainy items in the air with top and bottom sensors.

Coffee beans sorted by this versatile technology it helps to diagnose shape defect, color defect, and size defect.

Chute-Type Color Sorter

Chute type color sorter is specially designed according to the size, shape, and color of the grains.

Chute type color sorter provides excellent finishing with optimum structure.

Sortex provides best sorting solution for rice, grains, tea, dal, pulses and coffee etc

Chute type color sorters are of different types like 7 chute tri chromatic color sorter, 5 chute tri chromatic color sorter and 10 chute tri chromatic color sorting machine.

This electric sorting machine smoothly processed all food particles and maximizes the quality range.

Belt-Type Color Sorter

There are two main types of color sorting machines belt type color sorter and chute type color sorter.

Belt type color sorter is automatic sorting machine helps to sort material with steady transportation.

Start the process with hopper and outlet end is fitted with high-resolution camera acquisition card and finally, coffee beans captured at the end of the machine by the industrial camera.

This is one track sorting machine helps to reduce the damage rate.

Approximately during the processing time products remain static, no gravitation is required to make products aligned on track.

In short belt type color sorter helps to sort products with low damage rate and maximize the product yield.

Chapter 4: Main Parts of Coffee Color Sorter

There are different components that are simple but work efficiently like a feed funnel.

Approximately 50mm funnel diameter is required to pass all grains without vibration.

The slow conveyor started below 10mm of the conveyor belt. It helps to move smoothly 1-2 layers of coffee beans. This is a wide tube but only passes two lines.

Another important part of the coffee bean sorting machine is Guide Funnel it helps to make streamline of beans and is aligned in the center of the fast conveyor. A fast conveyor helps to separate the beans and control the fast fall of beans easily.

Linear Solenoids is not the only thing; brushes are attached to move the beans into rejected or selected destination. Different types of beans can be sorted efficiently with the linear solenoid of the coffee color sorter/bean sorting machine.

  • Bad beans
  • Undecidable beans
  • High-quality beans
  • Low-quality beans

Output funnel regulates the beans for the final destination and this is the last step of the conveyor belt.

The most important component of the coffee color sorter is the CCD camera which helps to capture images on the slow conveyor. Also, a flashlight is added additionally to get clear images with a sharp result.

Chapter 5: Coffee bean color sorter working principal

Color sorting is a process of analyzing raw material to find defective material. Many Chinese companies these days manufactured different color sorters like coffee bean color sorter, tea color sorter, optical color sorter, rice color sorter, and electronic color sorting machines.

These are highly précised and accurate bean sorting machines that provide 99% pure and high-quality yield and maximum throughput.

The principle of color sorting was developed in the past century but these days’ new updates and configurations introduced.

Factors affected on color sorting solutions

  1. Main and important factor is the resolution of Camera to capture the clear images of food items.
  2. Second thing is software algorithm.
  3. Feeding system and nozzle performance

Chapter 6: Step by step procedure of coffee cupping

What is coffee cupping?

Coffee cupping is a process that allows people to like coffee. In the late 19 century, it becomes a standard process on industrial scales.

But now a day, it becomes easy and common. It’s important to know that where their coffee comes from.

In older ways, the coffee roaster will roast their coffee and after two days it becomes evaluate.

Each coffee is measured in a specific ratio and then put on the table. Each coffee has 5 cups of ground coffee.

It identifies the quality of the coffee and also identifies the defects present between them.

Do you know what coffee cupping is and is there any concern with coffee bean color sorter?

I think no because it is not a common term.

I want to share with you what coffee cupping is, it is an industrial practice for checking the flavors of brewed coffee.

There are 6 detailed steps given below to explain the process of coffee cupping extensively.

  1. Selection of samples- you can choose 3 or 4 coffee samples of a different These are based on some features like flavor, aroma, and fragrance.
  2. Measurement- you can take 6 to 7 grams of coffee in 5 ounces of water.
  3. Brew- Start processing your coffee with the grinder it’s an easy and most recommended method of coffee cupping.
  4. By mixing again and again foam will appear on the upper surface of the coffee.
  5. Slurp- taking a large spoon and enjoy 3-4 slurps in each cup and get the natural flavor of coffee.
  6. Discuss and Compare- giving time to each cup. Take a slurp to start, take a break and then go back to the cup. You reorganize the real flavor. See which coffee taste is better cooler and hotter etc. Take your time and go back to each coffee 3-4 times to make sure all flavors are good.

Coffee cupping:

  • Dry fragrance-the gases emitted from the freshly ground coffee.
  • Wet Aroma- the elevation of vapors are emitted from the coffee when it is in the cup and once it is entered into the mouth it moves across the surface of the tongue.
  • Taste/flavor- the elevation of taste and flavor.

It’s important to realize that roasting will affect the quality of the coffee cup. Generally, we try to highlight the roast level that brings out the experience of coffee and say to you that it’s lightly roasted.

  • Acidy: it presents on the tip of the tongue and identifies the presence of sweet/tasty compounds.
  • Winey: it presents on the sides of the tongue and identifies the sour taste compounds.
  • Mellow: it is present on the tip of the tongue like as acidy but it identifies the less sweet compounds.

There are generally three stages in the cupping experience.

1:- smelling the grinds.

2:- smelling the taste of coffee from those grinds.

3:- testing the coffee using a spoon.

Cupping is a standardized process to determine the taste and aroma of the coffee and it is used to select and maintain the quality of the coffee bean. It is commonly used by coffee buyers and roasters but it is mostly used in cafes and allows the customers to get their taste of the coffee. All the customers are aware of every flavor of coffee and get what flavor and taste he wants.

Detail Procedure of coffee color sorting

If you want to check the standard procedure of coffee color sorting please keep the reading continue:

The products we need to purify are loaded in coffee bean color sorter via feed hopper.

The vibration of the feeder helps to flow the grains in a smooth way.

High-tech sensors and CCD cameras provide clear images of selected and rejected coffee beans.

Coffee sorting machine based on very useful and efficient techniques you can check

Computer processing software sends a signal to the ejectors to flow the fine products into the selected product hopper and rejected items flow to discharging hopper.

After passing into filter coffee beans will go through 2 stages.

  1. On the first stage quality coffee beans (grains) will be sorted.
  2. On the second stage, inferior beans (grains) will be subjected to sort.

After completion of the secondary sorting stage, good quality coffee beans will be further considered for resorting process and go back to the inlet of the color sorter.

On the other side, all the inferior grains will be considered as waste & discarded material.

Chapter 7: FAQs about coffee color sorter

Some of the questions people mostly ask about coffee bean color sorter:

What features must be in coffee sorting machines?

In 2019 customers want to get the precise quality output without wasting time at a reasonable price.

China provides the most efficient coffee sorting solutions which detect tiny defects with highly effective techniques.

How does Coffee color sorter help to classify and grade beans?

Grading means the classification of coffee beans according to size, color, and shape.

Coffee bean color sorter helps to categorize defective beans and selected beans during the sorting process.

Basically, coffee sizes are called grades, and coffee beans can be sorted precisely to get perfect yield with color sorting machines.

What are the features of coffee sorting machines and why we use color sorter?

If you want to gets the highest quality of food items according to the high standards of the market.

Then give a try to Coffee sorting machines which helps to sort the grains, rice, tea and coffee beans: roasted, Robusta and Arabica.

Coffee color sorter helps to manage the grading process of coffee beans and maximize the value of beans with LED lighting and high-resolution monochromatic CCD cameras.

Color sorter helps to increase the fine production level and reduce the operational cost.

Coffee bean sorting machine price is reasonable every person who belongs to the agricultural field must try to buy this automating sorting machine.


It’s very important to consider that sorting can only be effortless when there is an obvious understanding of how to operate a coffee bean color sorter.

To avoid any type of inconvenience you must select reputable SG to get a coffee sorting machine.

We make coffee bean color sorting, cost-effective and easy.

Contact us instantly we will provide you best customized sorting solution.

Edon Zheng

Edon Zheng

Hi, I'm Edon, the co-founder of, I've been running a factory in China that makes and exports color sorters for 8 years now, and the purpose of this site is to share with you the knowledge related to color sorters from a Chinese supplier's perspective.

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