Birch sap is known as the "liquid gold" due to its rich content of amino acids, minerals, and bioactive substances, which makes it highly sensitive to post-harvest processing techniques.

Researchers have pointed out that birch sap contains a large amount of bioactive enzymes and will undergo changes within about 15 hours after collection, causing significant inconvenience for batch production. How to preserve this gift from the forest in the shortest time and in the mildest way is a challenge that every practitioner must face.

Currently, the mainstream storage processes in the industry mainly fall into two technical routes: quick freezing and UHT (Ultra High Temperature) instantaneous sterilization + aseptic storage. Both routes have their applicable scenarios and together form the quality assurance system for birch sap from the forest to the factory.

 

I. Quick Freezing Process: Locking Time with Low Temperature

The core logic of quick freezing is to slow down all chemical reactions. By rapidly lowering the temperature, it inhibits microbial activity and enzymatic reactions, maximizing the retention of the sap's original state.

Key Parameters:

• Freezing window: The sap must be frozen within 24 hours after collection. Some high-end brands have shortened this window to 2-4 hours.

• Freezing temperature: Enter a rapid freezing chamber at -30°C to -35°C to quickly pass through the ice crystal formation zone.

• Storage temperature: After completion, transfer to a low-temperature cold storage at -16°C to -18°C for long-term preservation.

Technical Points:

The key to the quick-freezing process is "speed". If the cooling rate is not fast enough, large ice crystals will form inside the cells, piercing the cell walls and causing juice loss and flavor change upon thawing. This is why professional manufacturers invest in large-capacity low-temperature cold storages - for example, a company in Yichun has built a 20,000 cubic meter low-temperature cold storage to provide sufficient storage capacity for raw materials.

Applicable Scenarios:  As raw material reserves for subsequent processing; or for high-end products with extremely high requirements for the retention of active components.

 

II. UHT Instantaneous Sterilization Process: A Quick Strike at High Temperature

If quick freezing is about "stopping time", then UHT (Ultra High Temperature) is about "racing against time" - killing microorganisms in an extremely short time while minimizing the loss of heat-sensitive nutrients.

Technical Evolution:

Traditional high-temperature sterilization often requires a long time and causes significant damage to heat-sensitive substances such as amino acids and active enzymes. The emergence of UHT technology has completely changed this situation.

Take the practice of a company in Yichun as an example. Its innovative 4-machine linked UHT system can raise the temperature of the material from 0°C to 140°C instantly upon entering the equipment, with a sterilization time of only 5 seconds. This technological innovation has increased the production line's daily capacity from 100-200 tons to 450-500 tons, significantly boosting economic benefits.

Core Parameters:

• Sterilization temperature: 135°C - 140°C

• Sterilization time: 5 - 15 seconds

• Cooling method: Rapid cooling to room temperature or low temperature after sterilization

Post-sterilization processing:

After UHT treatment, the sap must be filled in a fully enclosed aseptic environment to avoid secondary contamination. This is where the value of the 【Qinon III】 aseptic collection bags and aseptic storage bags comes into play - the sap after sterilization is filled into food-grade aseptic bags, achieving long-term storage without preservatives.

Applicable Scenarios:  Direct use for filling terminal consumer products; or for raw materials that need long-term room temperature storage and long-distance transportation.

3

III. Comparison and Selection of the Two Processes

Comparison dimension Quick-freeze UHT sterilization + aseptic storage

Core principle Low-temperature inhibition of activity High-temperature sterilization of microorganisms

Processing temperature -30°C to-35°C 135°C - 140°C

Processing time several hours (the freezing process) 5 - 15 seconds

Storage conditions -16°C to -18°C refrigeration room temperature or low temperature (inside the sterile bag)

Activity retention Extremely (almost original) Higher (with a slight loss of heat-sensitive substances)

Equipment investment The construction cost of cold storage facilities is high.

The cost of UHT equipment is high

Operating costs Continuous power consumption Performance consumption

Logistics flexibility Depend on cold chain logistics Transportation at normal temperature is feasible

Applicable scenarios High-quality pure juice reserves Instant white birch juice drink


How to choose?

• If you are a raw material supplier and need to store for a long time or wait for the right sales opportunity, the quick-freezing process is a more reliable choice - it retains the greatest flexibility and allows you to decide on the processing direction based on market demand in the future.

• If you are a brand owner and need to directly convert the sap into a final product, UHT sterilization + aseptic storage is a more efficient path - one sterilization, and it can be filled, launched, and circulated.

 

IV. Supporting guarantees: From process to container

Regardless of which process route is chosen, the container is the "last mile" of quality.

Supporting for quick-freezing process:

• The collection bags need to have low-temperature resistance, not becoming brittle or cracking at -30°C

• The 【Qinon III】 series is equipped with "Qihua III" material, specially optimized for low-temperature environments

Supporting for UHT process:

• After sterilization, it needs to be filled into food-grade aseptic bags to ensure zero risk of secondary contamination

• Qichen provides 25L, 220L, and 1000L aseptic storage and transportation bags, suitable for different scale requirements

• The aseptic process is the same as that of the 【Qinon III】series, ensuring a clean environment from sterilization to filling

 

V. Conclusion: No superiority in processes, suitability is key

There is no absolute "best" storage process for birch sap; only the most "suitable" one.

Quick-freezing leaves options for the future; UHT quickly realizes value. Both technical routes are developing in parallel within the industry, jointly supporting the transformation of birch sap from a seasonal forest resource to a year-round stable supply of industrial raw materials.

According to the "Technical Regulations for the Collection, Transportation and Storage of Birch Sap" (T/HLJSLXH 012-2025) released by the Forestry Society of Heilongjiang Province, standardized transportation and storage conditions have been incorporated into industry standards. This means that storage processes are gradually moving from enterprise self-selection to standardization and normalization.

As a service provider in the upstream of the industrial chain, Qichen's mission is not only to provide qualified containers but also to accompany customers in understanding the processes and choosing the right path, ensuring that every drop of sap can reach its destination in the most suitable way.

 

If you need to consult on the selection of collection bags or aseptic storage and transportation bags, please contact the Qichen team. We are willing to discuss with you to find the most suitable solution for your business.

Qichen Packaging Materials (Wuxi) Co., Ltd.

March 2026