Application of a preservative on a fresh product

Fresh products have a limited shelf life. Keeping their native quality while extending the sell-by date is a challenge. Recent advances offer a sensible solution with regards to the consumer trend towards natural products.

Updated Aug 02, 2021 - 10 min Read


Core products

The range of fresh products forwarded to the consumer is wide and expanding: diced fruits mixes, salads, sliced meat, prepared meals, bakery … Alterations may come from physical (staling), chemical (oxydation), enzymatic (oxydation) or microbial causes.



Solutions have been developed: minimal processing, hygienic production conditions, packaging, modified atmosphere and ultimately the application of a surface substance mix …
The range of ingredients matches the diversity of food products:
Chemical organic or inorganic preservatives: BHA, BHT, sorbates, acetic acid, alcohol, nitrites… They are usually incorporated in the food product itself e.g. processed meat
Microbial cultures e.g. lactic bacteria, yeast… They have the ability to grow and occupy “space” thus limiting the growth of other bacteria while not being harmful
Bacteriophages are viruses that have the ability to destroy the bacterial population
The choice of the ingredient depends on the product sensitivity to a specific alteration which is the most limiting the shelf life. The application of an ingredient is used in combination of other preservation techniques e.g. modified atmosphere packaging to create a hurdle effect against alteration.


How does it work?

It is a continuous operation in the industry.
After coating, the product must be air-tight packed to prevent the alteration and loss of the preservative itself. After coating, the product needs to be stored in a stove at regulated temperature and moisture during 12 – 24 hours to finalize the crystallization.


Forming of the packaging e.g. thermoformed plastic tray



Filling of the tray with the food product(s)


Application of the preservative



Closing of the tray


Coating system

To achieve an even disribution, spraying the preservative is the preferred solution.


Coating system

The spraying system must be positionned on top of the trays between filling and closing.


How do you measure your success?

Key quality features

The evaluation regards as much the product as the packaging


The targeted sell-by date is checked by test


The application of a preservative does not affect the product itself


The application does not affect the package : smear, condensation, sealing zone

Key quality parameters

The process displays critical factors to control


Choice of the preservative as a function of the product and sheld-life


Accurate dosage and application. Homogenous distribution


Hygiene of the system and operation. Safety and health hazards issues for some preservatives: alcohol, microbial cultures