Fruit purée is widely used by the food and beverage industry and is commonly packed in aseptic or frozen drums for industrial distribution.
However, during storage or transport, it is sometimes possible to observe that drums become swollen or pressurized.
This phenomenon is not random. In most cases, it is linked to gas production inside the drum, usually caused by microbiological activity, fermentation or temperature abuse.
Understanding why fruit purée drums swell is essential for quality control, food safety and logistics management.
Several factors may cause swelling in fruit purée drums. These causes can occur individually or combined.
The most common ones are related to microbial activity, chemical reactions or storage conditions.
The most frequent cause of drum swelling is fermentation caused by microorganisms.
When yeast or bacteria are present in the purée, they may metabolize sugars and generate gases such as:
Carbon dioxide (CO₂)
Ethanol
Organic acids
Even a small microbial contamination can slowly generate enough gas to increase pressure inside the drum, causing visible swelling.
Typical microorganisms involved include:
Yeasts (Saccharomyces species)
Lactic acid bacteria
Spoilage bacteria
This risk is particularly important in high-sugar fruit purées, such as strawberry, mango, apple or blueberry.
Temperature control plays a key role in maintaining fruit purée stability.
If frozen or refrigerated purée is exposed to higher temperatures during transport or storage, microbial activity may start or accelerate.
For example:
Frozen purée partially thawing during transport
Storage above recommended temperature
Long transit times without temperature control
Once microorganisms begin fermenting the natural sugars in the purée, gas formation can quickly build pressure inside the drum.
In some cases, swelling can originate from insufficient pasteurization or contamination during filling.
If the purée contains residual microorganisms before packaging, they may remain inactive at first but later grow under favorable conditions.
This is why industrial manufacturers apply strict controls such as:
Pasteurization
Aseptic filling
Hygienic processing
Microbiological testing
Even small deviations in processing can lead to slow fermentation during storage.
Although less common, certain chemical reactions inside the purée may also produce gas.
These reactions can involve:
Degradation of organic acids
Enzymatic activity
Reactions with packaging materials
However, in most cases within the fruit industry, microbial fermentation remains the primary cause of swelling.
A swollen drum should always be treated with caution. Pressurized containers may indicate microbiological spoilage, which can affect the products safety and changes changes of flavor and aroma
Prooducts with this problem finish her Shelf life and are not available for iIndustrial processing performance
Before using the product, manufacturers normally perform several checks:
Visual inspection
Gas release evaluation
Microbiological analysis
pH measurement
Sensory evaluation
If fermentation has occurred, the purée may show off-flavors, alcohol formation or excessive acidity.
Preventing swelling starts with strict control throughout the production and logistics chain.
Key preventive measures include:
Proper pasteurization
Ensuring correct thermal treatment eliminates most microorganisms before packaging.
Aseptic filling
Maintaining sterile conditions during filling prevents contamination after processing.
Cold chain control
Frozen or refrigerated purées must remain within their recommended temperature range during storage and transport.
Quality control testing
Routine microbiological testing helps detect contamination before products leave the facility.
Reliable suppliers
Working with experienced fruit processors reduces the risk of fermentation issues in industrial batches.
WE DISTRIBUTE OUR PRODUCTS PROVIDING THE NECESSARY PACKAGING ACCORDING TO THE NEEDS OF OUR CUSTOMER
A leader in fruit and vegetable juices and concentrates, we stand out for our excellence and innovation. Our products are 100% plant-based, sustainable, and of the highest quality.
As international manufacturers and distributors, we guarantee safe and timely deliveries. We work with you to drive your business success with customized solutions perfectly tailored to your company.
Trust Baor to help you achieve your goals and enjoy a passionate and reliable partnership!
Contact us today and discover how our concentrated fruit bases can take your culinary vision to new heights.
All our products are stored at the appropriate temperature in state-of-the-art refrigerated facilities and chambers.
We manufacture and distribute internationally, preserving the cold chain, guaranteeing the quality of each of our products.
Our logistics operations through international operators guarantee the receipt of the product in perfect conditions.
