Advanced Technologies
Scaling Processes for Industrial Use

Light-based processes enable contact-free, energy-efficient methods for the microbial decontamination of surfaces, such as those on food, packaging, or equipment. Depending on the process and parameters, microorganisms can be effectively inactivated. At the same time, sensory properties can be specifically influenced, such as crust formation and browning, or the formation of certain vitamins.

UV-C light (200–280 nm) acts photochemically by being absorbed by DNA, thereby inhibiting replication and transcription. It is used, among other things, for surface disinfection as well as for air and water treatment, and can inactivate enzymes and preserve bioactive compounds in food. The DIL has a continuous UV-C system available that enables uniform treatment from three sides with variably adjustable lamp distance and treatment time, ensuring reproducible results under conditions relevant to food regulations.

Pulsed light (PL) operates with very short, high-energy pulses across a broad spectrum (180–1,100 nm) and combines photochemical and photothermal effects. This causes multifaceted damage to microorganisms, e.g., to DNA, cell walls, and proteins. The DIL test system delivers up to three pulses per second with 505 joules of pulse energy, with flexible adjustment of the distance, number, and interval of the pulses.

Infrared (IR) is primarily used for rapid surface heating and sensory enhancement, and—through the photothermal effect—also aids in the inactivation of bacteria and enzymes. The IR system at the DIL (18 kW) allows for variable settings of time and distance and is used, for example, for browning, roasting, and drying, as well as in combination with other processes.

Pulsed electric fields (PEF) are an innovative, non-thermal method for altering the structure of and inactivating microorganisms in food processing. Short, high-voltage pulses induce electroporation, selectively opening cell membranes and thereby offering advantages in extraction, texture modification, and preservation through energy-efficient processing—for example, for fruits, vegetables, and fruit juices.

PEF is primarily used for structural modification—by softening tissue and improving mass and heat transfer—and for the inactivation of vegetative microbial cells without causing thermal damage to the product, particularly in liquid foods. The DIL has adapted the process for industrial applications; nearly 300 systems are in use worldwide, including in potato processing and for the preservation of liquid products. Further applications are being researched in collaboration with ELEA GmbH.

At the DIL’s High-Pressure Center, we assist food and ingredient manufacturers in evaluating and further developing pressure-based technologies. These include HPP, UHPH, supercritical and subcritical water extraction (SWE), and dynamic shock wave processes.

Our research explores how high pressures can be used to gently preserve food, selectively modify its structure, or develop new products and ingredients. Together with industry partners, we evaluate pressure-based technologies for various applications and develop scalable, product-specific solutions.

To this end, we have a fleet of food-grade equipment, including batch systems capable of operating at up to 6,000 bar and 120 °C, a 55-liter HPP system for packaged products, a continuous UHPH system (90 L/h at approx. 3,000 bar), systems for supercritical and subcritical water extraction, and a prototype for dynamic shock wave treatment. HPP is particularly suitable for heat-sensitive, packaged products, while UHPH uses pressure and shear forces to improve emulsions, functionalize ingredients, and selectively break down microorganisms. In addition, SWE is being researched as an environmentally friendly alternative to solvents for the extraction of bioactive substances.