HPP Technology
19th Century HPP equipment
The food industry is increasingly moving towards new product development and innovative propositions through new processing methods that allow doing things you could not do before.
One of the most successful developments made to the moment is High Pressure Processing (HPP).
High Pressure Processing is a cold pasteurization technique which consists in subjecting food, previously sealed in a flexible and water-resistant packaging, to a high level of hydrostatic pressure (pressure transmitted by water) up to 600 MPa / 87,000 psi for a few seconds to a few minutes. It is the same effect than placing the food 60 Km deep into the Ocean would have -if an Ocean this deep existed-.
Although the Non Thermal Pasteurisation effect of high pressure on foods is known since the XIX Century, it was not until the 1990's that the first HPP products were developed. Particularly since 2000, High Pressure Processing has been successfully implemented in all type of food industries worldwide.
High Pressure Processing is a natural, environmentally friendly process that respects the ingredient and helps maintain the fresh food characteristics like flavour and nutrients. It is a real alternative to traditional thermal and chemical treatments.
Listeria monocytogenes. Before (left) and after (right) HPP
What is High Pressure?
High Pressure Processing (HPP) is a cold pasteurization technique by which products, already sealed in its final package, are introduced into a vessel and subjected to a high level of isostatic pressure (300–600MPa/43,500-87,000psi) transmitted by water.
Pressures above 400 MPa / 58,000 psi at cold (+ 4ºC to 10ºC) or ambient temperature inactivate the vegetative flora (bacteria, virus, yeasts, moulds and parasites) present in food, extending the products shelf life importantly and guaranteeing food safety.
High Pressure Processing respects the sensorial and nutritional properties of food, because of the absence of heat treatment, and maintains its original freshness throughout the shelf-life.
Diagram of operation of a HPP unit
Advantages
To meet the demands of the XXI century consumer (convenience foods, higher sensorial and nutritional quality, additive free/natural, functional products, etc.), food companies need to innovate by using the latest non-thermal technologies, and High Pressure Processing is the most relevant one.
Thermal methods, traditionally used in food industry for food preservation, carry disadvantages like vitamin destruction or flavour changes that can be avoided with HPP.
High Pressure Processing Technology (HPP) Main Advantages
- Characteristics of the fresh product are retained, sensorial and nutritional properties remain almost intact: Greater food quality.
- Destroys pathogens (Listeria, Salmonella, Vibrio, Norovirus, etc.): Food safety and exportation.
- Extends product shelf life: Lower returns, improved customer satisfaction.
- Reduces drastically the overall microbiological spoiling flora: Higher quality along shelf life.
- Avoids or reduces the need for food preservatives: Clean label foods (Natural/Additive Free).
- New innovative food propositions. Products that can not be thermally treated can now be High Pressure Processed: Innovation and competitive advantages
- Able to shuck molluscs or extract crustacean meat without boiling: Higher yields, fresh flavour, minimum hand labor...
- Only needs water (which is recycled) and electricity: Environmentally friendly.
- Hicks, D. T.; Pivarnik, L. F.; McDermott, R.; Richard, N.; Hoover, D. G. & Kniel, K. E. Consumer awareness and willingness to pay for high-pressure processing of ready-to-eat food. Journal of Food Science Education 2009, 8(2), 32–38
- Heinz, V. & Buckow, R. Food preservation by high pressure. Journal of Consumer Protection and Food Safety 2010, 5(1), 73–81.
- Patterson, M. F. A Review: Microbiology of pressure-treated foods. Journal of Applied Microbiology 2005, 98(6), 1400–1409.
