A good day starts with a cup of coffee. At home, in the office, or on various social occasions, we can find coffee. Coffee has become an indispensable part of our life. Today we will talk about coffee powder production line.
What is coffee?
Coffee is a beverage made from roasted coffee beans. Coffee, the main popular drink in the world, has a history of thousands of years in the process of human civilization. Because of its refreshing effect and good taste, it has been the majority of consumers love.
Coffee solid beverage is a solid beverage made from coffee beans and coffee products (ground coffee powder, coffee extract liquid or its concentrate liquid, instant coffee, etc.) as raw material, with or without other food materials. It includes instant coffee, ground coffee (roasted coffee), and instant coffee drinks. The following takes instant coffee as an example to introduce the production of coffee-solid beverages.
How about the process of coffee beans?
The fruit of the coffee tree is generally called coffee cherry, which is composed of the outer skin, pulp, pectin, endocarp, silver skin, and innermost embryo. The coffee bean we usually talk about is actually the embryo inside.
After we pick the coffee fruit, we need to remove the peel and pulp to let it becomes a coffee bean. Processing is generally the work of planting the manor. The manor processes the coffee fruit into dried green coffee beans and then sells and transports them. The coffee is processed differently from plant manor to plant manor, and the different processing methods affect the taste of coffee to some extent. It takes many steps to separate coffee beans, coffee beans processing methods mainly include dry/natural, wet/washed, and honey & pulped natural. See here for details.
What is the process of coffee powder production line?
Coffee bean – Pretreatment – Mixing – Roasting – Grinding – Extraction – Filtration – Concentration – Drying – Blending – Packaging
Pretreatment
Select and clean the raw coffee beans, remove the mixed metal, stone particles, dust, and other foreign matters, and remove the broken beans, moldy beans, etc. The chief purpose is to separate and clean through vibrating screen, air pressure conveying or vacuum conveying, remove the impurities, crushed stones, and defective beans in the original coffee beans, and select excellent coffee beans, the medium-seed coffee is especially suitable for preparing instant coffee.
Mixing
Here mainly refers to the choice of coffee beans, which can be single-origin or blend origin. Single-origin is a single variety of coffee beans. Blend origin refers to a mixed formula containing more than two kinds of coffee beans. Blend coffee is a combination of coffee beans from different varieties and places, can control the flavor (acidity and bitterness) of coffee, improve the commodity value of coffee, make the best use of everything and improve the economic value. We can choose single or blend-origin coffee beans as needed.
Roasting
The purpose of roasting is to give the coffee its flavor, make coffee crisp and easy to grind, change some chemical components in coffee beans and remove some water. Roasting is the decisive step, which directly determines the flavor and quality of coffee, and roasting time and temperature are the key factors.
The longer the roasting time, the darker the color of the beans. When roasting is not enough, it will have a bad smell, and be difficult to grind, can not achieve a better flavor; when the roasting time is too long, it will produce a peculiar smell due to carbonization and lack of aroma. The roasting time should not exceed 20min, which can minimize the volatilization of aromatic substances.
We would better roast the different kinds of coffee beans separately, and control the highest temperature at 230 ~ 250 ℃, which will produce a better aroma. When reaching the required roasting degree, stop heating and spray a certain amount of cold water into the oven, and discharge the roasted coffee beans.
Grinding
After roasting, we would better store the coffee beans for one day to release the carbon dioxide and other gases produced during the roasting process, at the same time, it also fully absorbs the moisture in the air and softens the particles, which is conducive to extraction.
The degree of grinding depends on the extraction equipment used and the proportion of solvent used. When we grind the coffee beans into fine-grained, it is easy to extract and can achieve high-efficiency extraction with a small amount of water, the obtained coffee is thicker than coarse-grained coffee, but it is difficult to filter.; if we grind the coffee bean into coarse-grained, it needs a lot of water, higher temperature, and pressure, but is easy to filter. The fine-grained coffee powder will release more fatty acids, oil, and protein, but the too fine-grained coffee powder is easy to lose its flavor (that is, volatile aromatic components of coffee).
Extraction
It is the most complex core process in the production of instant coffee. Temperature and pressure are the two most direct parameters in the extraction process.
The soluble matter of roasted coffee accounts for about 25%, and the extraction rate can reach 30% at 100 ℃. When the temperature reaches 180 ℃, extract some high molecular carbohydrates, which increases the extraction rate by 10% ~ 20%. These high molecular carbohydrates are conducive to the combination of aromatic substances, to achieve the effect of adjusting flavor. However, when the temperature is higher than 190 ℃, there are some undesirable flavor substances will be extracted from the extract. The extraction pressure is about 0.9 ~ 1.5MPa.
The extraction time and extraction rate are related to the product quality. Increasing the temperature and pressure within an appropriate range can shorten the extraction time, reduce the worse extracts and ensure the product quality.
The higher the extraction rate, the higher the output, but the quality, should not be too high. If the product has a sour, bitter, and astringent taste, it indicates the extraction rate is high and would better reduce the extraction.
Filtration
Liquid-solid separation, many solids will remain in the extracted coffee liquid, which requires liquid-solid separation of coffee solution. Generally, using a dish separator can achieve a desirable separation effect.
Concentration
Generally, for concentration, we adopt vacuum concentration. During vacuum concentration, the vacuum degree is more than 0.09 MPa, the boiling point of water is only about 50 ℃, then speeds up the evaporation and concentration of liquid. The concentration of concentrated solution generally does not exceed 60%. Since the temperature of the coffee concentrated solution from the evaporation tower is higher, we need to cool it before being sent to the storage tank, to reduce the loss of aromatic substance.
Drying
It is the method to form an instant coffee powder, and it will have a great impact on the quality of coffee in the processing process. The drying method of coffee concentrate is mainly spray drying and vacuum freeze-drying.
Spray drying (Spray Dryer SD), the coffee liquor is directly delivered to the nozzle on the top of the drying tower through the pressure pump. The inlet temperature of the drying tower is 250~270 C, the outlet temperature is 110~130 C, and adjust the nozzle and spray pressure to make the ejected coffee pulp be the coffee particles. In spray drying, we should pay attention to the concentration of the coffee solution, higher concentration is conducive to the formation of particles, but exceed high concentration will make the atomization degree too low, resulting in poor atomization. Therefore, we should control the concentration of coffee solution at 30%~40%.
Spray drying, make the coffee solution sprayed into the drying chamber, allowing the water evaporates quickly and then form the dry powder.
However, by high-temperature heating to achieve the drying effect in the processing process, the aroma of coffee has been somewhat volatilized, so the aroma of instant coffee produced by this method is not strong enough. At the same time, the spray-drying coffee powder is too fine, and when the particle density is large, it is not easy to dissolve, which will take some trouble to consumers.
Freeze drying ( Freeze Dryer FD) first transfers the coffee concentrate to the freezing bin(where the temperature reaches minus 50 ℃) to form ice cube, and break the ice cubes into coffee particles. Now the coffee particles still contain some water, transfer the coffee particles into a vacuum environment and heating it, achieve complete dehydration through the sublimation principle. In this way, the treated coffee ice has become coffee powder.
The freeze-dried coffee produced by vacuum freeze-drying technology avoids the influence of high temperature on the quality of coffee during the spray-drying process, and retains the original flavor and taste of roasted coffee as much as possible, which significantly improves the quality of coffee. The instant coffee produced by the freeze-drying method is more popular.
Blending
To improve the drinking quality of coffee powder and adapt to the tastes of various regions, we would better add appropriate ingredients to enhance the flavor, taste, color, appearance, and aroma of coffee. Add protein, glucose and pectin can make the flavor special.
Packaging
The coffee powder is easy to regain moisture and agglomerate, which will make the aroma of coffee powder loss. Therefore, coffee powder packaging should adopt a moisture-proof package, and maintain a constant vacuum (0.098mpa) to prevent moisture absorption. The packaging materials include iron cans, glass bottles, and flexible packaging of composite materials.
Canned coffee
Bottled coffee
Small sachet coffee
Stand up pouch coffee
Now I think you already have a general idea of the coffee powder production line. If you are planning to build a coffee powder production line, welcome to contact us to know more about the production line!
