1000L Rice Wine Fermentation Tank Project for Nerd Makgeolli, South Korea

Project Location:South Korea
Customer: NERD
Industry: Traditional Korean Rice Wine Production
Final Product:Makgeolli
Equipment Supplied: Two 1000L Mixing Tanks and Eight 1000L Rice Wine Fermentation Tanks
Main Application: Primary fermentation, rice-wine dilution, blending, temperature control, sampling and sanitary cleaning

Project Background

NERD is a Korean rice-wine producer specializing in makgeolli, a traditional fermented beverage made from rice, water and fermentation cultures.

According to the customer’s project information, NERD’s makgeolli was selected as a designated beverage for the 2025 APEC CEO Summit in South Korea. This project therefore required equipment that could support both traditional fermentation characteristics and more controlled commercial production.

To support its makgeolli production process, NERD selected ZR Brew to provide a customized stainless steel processing system consisting of:

•  Two 1000L stainless steel mixing tanks
• Eight 1000L rice wine fermentation tanks

The fermentation tanks support the primary open fermentation stage, while the mixing tanks are used during the water-dilution and final blending stage before packaging.

Rather than applying a standard beer-fermentation configuration, ZR Brew developed the vessel arrangement around the specific process requirements of Korean rice wine.

 Understanding the Customer’s Makgeolli Process

The customer’s production process follows these principal stages:

1. Rice soaking
2. Rice steaming
3. Spreading and cooling the cooked rice to approximately 24–26°C
4. Transferring the rice into the fermentation tank
5. Adding fermentation starter and water
6. Mixing the ingredients inside the vessel
7. Open primary fermentation at a controlled temperature for approximately five to seven days
8. Coarse filtration to separate the rice solids
9. Water dilution and product blending
10. Filling and packaging

Each stage influences the flavor, acidity, body, fermentation activity and final consistency of the makgeolli.

The equipment therefore needed to support more than simple liquid storage. It had to accommodate rice mash, fermentation cultures, suspended solids, temperature-sensitive biological activity and the final dilution process.

 The Customer’s Main Equipment Requirements

 Maintaining an Open Fermentation Environment

Unlike a conventional pressurized beer fermenter, the customer required atmospheric open fermentation tanks.

The open fermentation environment allows limited oxygen exposure during the early fermentation process. This supports the natural development of lactic acid bacteria, which contribute to the gentle acidity and characteristic sweet-and-sour balance associated with makgeolli.

The vessel therefore had to support open fermentation without being designed around carbonation pressure or fully sealed beer-fermentation conditions.

 Keeping the Rice Mash Uniform

Rice wine mash contains cooked rice, water and fermentation cultures. Without sufficient movement, solids may settle or become unevenly distributed.

The customer therefore required a mixing function that could:

• Distribute the fermentation starter evenly
•  Mix the cooked rice and water
•  Reduce localized concentration differences
•  Support more uniform contact between the rice, microorganisms and liquid
•  Assist with blending during the dilution stage

Controlling Fermentation Temperature

Makgeolli fermentation generates heat and is sensitive to changes in temperature.

Uneven temperature distribution inside the fermentation tank can cause different areas of the mash to ferment at different rates. The customer therefore required a cooling structure capable of supporting consistent heat exchange across the vessel.

 Supporting Sampling Without Disturbing Fermentation

The production team needed to check the mash during fermentation while minimizing disturbance to the vessel environment.

Opening or manually removing large quantities of mash could introduce unnecessary interference. A dedicated sampling point was therefore required for faster and more controlled sample collection.

 Reducing Manual Cleaning

Rice mash can leave starch, solids and fermentation residue on the internal surfaces of the tank.

The customer needed an internal cleaning system that could improve water coverage, reduce manual access and prepare the vessels more efficiently for the next production cycle.

 ZR Brew’s Customized Equipment Solution

ZR Brew supplied a vessel system tailored to the customer’s makgeolli production workflow.

 Equipment Configuration

設備	Quantity	容量	主な機能
Stainless Steel Mixing Tank	2 Units	1000L Each	Water Dilution, Product Adjustment, and Final Blending
Rice Wine Fermentation Tank	8 Units	1000L Each	Open Primary Fermentation of the Rice Mash

The use of multiple 1000L fermenters gives the customer separate vessels for organizing different fermentation batches.

The two dedicated mixing tanks allow the dilution and blending stage to be handled independently from active fermentation. This separation helps create a clearer production flow and avoids using fermentation vessels for every downstream processing step.

 1000L Stainless Steel Mixing Tanks

The two 1000L mixing tanks are used primarily after coarse filtration, when the fermented rice wine is diluted with water and adjusted before filling.

A dedicated stainless steel mixing tank supports the controlled combination of filtered rice wine and added water. The agitator helps distribute the liquid throughout the tank and reduces the risk of uneven product concentration.

 Main Functions of the Mixing Tanks

•  Receiving filtered rice wine
•  Adding water according to the product formulation
•  Mixing the diluted product
•  Supporting consistent concentration throughout the batch
•  Preparing the product for the filling stage

Separating dilution and blending from primary fermentation allows each vessel to perform a clearly defined process function.

The fermentation tanks provide the biological environment required for rice-wine production, while the mixing tanks provide the mechanical blending required before packaging.

 Eight 1000L Rice Wine Fermentation Tanks

The eight 1000L fermentation tanks form the core of the makgeolli production system.

Each rice wine fermentation tank is designed around the customer’s atmospheric fermentation process rather than a high-pressure beer-fermentation process.

 Atmospheric Open Fermentation Design

The tanks support fermentation under atmospheric, open-vessel conditions.

This configuration permits limited oxygen exposure, helping create conditions in which naturally occurring lactic acid bacteria can develop alongside the main fermentation activity.

The resulting natural lactic-acid formation contributes to the balanced acidity associated with traditional makgeolli.

The purpose of the open design is not uncontrolled exposure. It is to provide a process-appropriate fermentation environment for this specific rice-wine application.

 Integrated Mixing Motor

A mixing motor supports uniform movement of the rice mash inside the fermenter.

The agitator helps combine:

•  Cooked rice
•  Water
•  Fermentation starter
•  Active fermentation liquid
  Suspended rice solids

More uniform mixing supports better ingredient distribution and reduces localized differences inside the vessel.

The agitator is also useful when water and process ingredients are first added to the tank, helping the production team establish a more consistent starting mixture.

 Ice-Water Cooling Jacket

Each fermentation vessel is equipped with an ice-water jacket to support controlled heat exchange.

The jacket helps remove fermentation heat and maintain a more stable environment throughout the vessel.

Its main functions include:

• Supporting controlled mash temperature
•  Reducing temperature differences between different areas of the tank
•  Removing heat generated during active fermentation
•  Helping the operator manage the five-to-seven-day primary fermentation stage
•  Supporting repeatable process conditions between batches

The jacket does not replace process management. Cooling performance still depends on the available chilled-water system, inlet temperature, flow rate, ambient conditions and fermentation load.

However, the jacket provides the vessel-side structure required for temperature regulation.

 PT100 Temperature Sensor

A PT100 temperature sensor is used to measure the temperature of the rice mash.

PT100 sensors are suitable for process applications requiring stable and accurate temperature monitoring. In this project, temperature information helps the operator evaluate fermentation conditions and manage the cooling-water supply.

The sensor supports:

•  Real-time temperature observation
•  Cooling-system adjustment
•  Identification of abnormal temperature changes
•  Comparison between fermentation batches
•  More controlled process records

Because makgeolli fermentation is biologically active, reliable temperature measurement is important for production control.

 Sanitary Sampling Valve

A dedicated sampling valve allows the operator to remove a small quantity of mash or liquid during fermentation.

Compared with opening the tank or manually removing a large sample, the valve provides a faster and more controlled sampling method.

It helps the production team check:

•  Fermentation progress
•  Aroma development
•  Acidity
•  Sweetness
•  Texture
•  Visual condition
•  Readiness for filtration

Only a small quantity needs to be removed, helping reduce broad disturbance to the mash and maintain a more stable fermentation environment.

 Internal Cleaning Ball

A cleaning ball is installed inside the tank to distribute cleaning liquid across the internal surfaces.

After fermentation, starch, rice solids and fermentation residues may remain on the tank wall, cooling area, internal fittings and lower sections.

The cleaning ball supports:

•  Internal rinsing
•  Wider cleaning-water coverage
•  Removal of loose residues
•  Reduced dependence on manual cleaning
•  Faster preparation for the next batch
•  More consistent cleaning procedures

The final cleaning result still depends on cleaning pressure, flow rate, chemical concentration, temperature, cleaning time and the customer’s sanitation procedure.

Insulation Layer

The insulation layer helps reduce heat transfer between the rice mash and the surrounding environment.

It supports the fermentation process by:

•  Reducing the influence of room-temperature fluctuations
•  Helping retain the target mash temperature
•  Supporting the cooling jacket
•  Limiting unnecessary heat gain
•  Creating more stable conditions during the fermentation cycle

The insulation, cooling jacket and PT100 sensor work together as a coordinated temperature-management system.

The sensor provides temperature information, the cooling jacket enables heat removal, and the insulation helps preserve the controlled environment.

How the Equipment Fits the Complete Production Process

 Stage 1: Rice Preparation

Rice is soaked and then steamed. After steaming, it is spread out and cooled to approximately 24–26°C.

Cooling before transfer is important because excessively hot rice could negatively affect the fermentation cultures.

 Stage 2: Tank Filling and Initial Mixing

The cooled rice is transferred into a 1000L fermenter.

Fermentation starter and water are added, and the integrated agitator helps distribute the ingredients throughout the vessel.

This creates a more uniform rice mash before the main fermentation stage begins.

 Stage 3: Open Primary Fermentation

The mash undergoes open fermentation for approximately five to seven days under temperature-controlled conditions.

During this stage:

•  Limited oxygen exposure supports the intended fermentation environment
•  The cooling jacket removes excess fermentation heat
•  The insulation reduces external temperature influence
•  The PT100 sensor provides temperature measurements
•  The sampling valve allows controlled process checks

 Stage 4: Coarse Filtration

After primary fermentation, the rice wine passes through a coarse filtration stage.

This separates larger rice solids from the fermented liquid.

Stage 5: Dilution and Blending

The filtered rice wine is transferred to one of the two 1000L mixing tanks.

Water is added according to the customer’s product formulation. The mixing system distributes the added water throughout the batch, supporting a consistent final blend.

This is the principal application of the stainless steel mixing tank within the project.

 Stage 6: Filling

After the product has been adjusted and mixed, it is transferred to the filling stage.

The case scope provided covers the mixing and fermentation vessels. Specific filling-machine parameters were not included in the project information and are therefore not described here.

 Why Separate Fermentation and Mixing Tanks Were Used

Using dedicated fermenters and separate mixing tanks creates a clearer process division.

 Fermentation Tanks

The eight fermentation tanks are designed to provide:

•  A suitable environment for rice-mash fermentation
•  Atmospheric open fermentation
•  Temperature management
•  Controlled sampling
•  Internal cleaning
•  Batch separation

 Mixing Tanks

The two mixing tanks are designed to provide:

• Water addition
• Dilution
•  Concentration adjustment
•  Uniform blending
•  Preparation before filling

This arrangement prevents the production team from relying on the same vessel for every process stage.

While one batch is being diluted or prepared for packaging, other batches can remain in fermentation. This supports a more organized workflow without requiring the biological fermentation stage and final blending stage to occupy the same equipment.

 Project Value for NERD

The completed system gives NERD a vessel configuration developed around the actual makgeolli process rather than a standard beer-production layout.

 Process-Appropriate Fermentation

The atmospheric open fermenters support the limited aerobic conditions required by the customer’s traditional rice-wine process.

 Controlled Temperature Management

The cooling jackets, insulation layers and PT100 sensors provide the equipment foundation needed to monitor and manage fermentation temperature.

 Uniform Ingredient Distribution

The mixing motors help distribute rice, water and fermentation starter during tank preparation and support uniform blending during later processing.

 Better Batch Organization

Eight separate fermenters allow different batches to be managed independently according to their individual fermentation progress.

 Dedicated Dilution Stage

Two stainless steel mixing tanks provide a separate processing area for water addition and final product adjustment.

 Controlled Sampling

The sampling valves allow small quantities to be removed without extensively disturbing the rice mash.

 More Efficient Cleaning

Internal cleaning balls help distribute cleaning liquid inside the vessels and reduce the amount of manual internal cleaning required.

No numerical production increase, labor reduction, cleaning-time reduction or product-yield improvement was disclosed for this project. The benefits described above represent the intended functional value of the selected equipment configuration rather than independently measured performance results.

 Why ZR Brew Was Selected

This project required more than standard stainless steel tanks.

ZR Brew needed to understand the customer’s complete rice-wine process, including:

• Cooked-rice handling
•  Fermentation starter addition
• Open fermentation
•  Lactic-acid development
•  Mash-temperature control
•  Sampling requirements
•  Rice-solid separation
•  Water dilution
•  Final blending
•  Cleaning between batches

Based on these requirements, ZR Brew configured the project with dedicated fermentation and mixing equipment rather than applying a generic brewing-tank package.

The project reflects ZR Brew’s capability to support not only beer production, but also rice wine, fermented beverages, kombucha, cider, wine and other customized biological fermentation applications.

Project Summary

Project Item	Details
Customer	NERD
国	South Korea
Final Product	Makgeolli Rice Wine
Mixing Equipment	Two 1000L Stainless Steel Mixing Tanks
Fermentation Equipment	Eight 1000L Rice Wine Fermentation Tanks
Fermentation Method	Atmospheric Open Fermentation
Primary Fermentation Time	Approximately 5–7 Days
Rice Cooling Temperature	Approximately 24–26°C Before Tank Transfer
Temperature Control	Ice-Water Jacket, Insulation, and PT100 Sensor
Mixing Function	Motor-Driven Agitation
Sampling	Dedicated Sampling Valve
Internal Cleaning	Cleaning Ball
Mixing-Tank Application	Water Dilution and Final Product Blending

 Customized Rice Wine Fermentation Equipment from ZR Brew

Rice wine production requires equipment designed around the characteristics of the raw material, fermentation cultures and final beverage.

A standard beer fermenter may not automatically meet the requirements of an open makgeolli process. Vessel pressure, opening structure, agitation, cooling, sampling, cleaning and downstream blending must all be considered according to the actual production method.

ZR Brew provides customized:

•  Rice wine fermentation tanks
•  Atmospheric open fermenters
•  Stainless steel mixing tanks
•  Jacketed fermentation vessels
•  Agitated processing tanks
•  Wine and cider fermentation equipment
•  Kombucha fermentation systems
•  Custom stainless steel beverage-processing vessels

Each system can be planned according to the customer’s batch capacity, production process, available utilities, temperature requirements, facility layout and future expansion plan.

 Discuss Your Rice Wine Production Project

Planning a makgeolli, rice wine or fermented beverage production line?

Send ZR Brew your required batch capacity, raw materials, fermentation process, temperature range, vessel quantity, mixing requirements and facility layout. Our project team will help develop a customized fermentation and blending configuration for your production process.