Pos 11: External preheaters allow to optimize treatment conditions and to make use of synergistic effects of heat. They can be used in a scale of 20 to 200 l/h. Pos 12: With an external cooler the product can be cooled after the treatment, in a scale of 20 to 200 l/h.
Pulsed Electric Fields in fruit juice processing Stefan Toepfl
Facts and Figures Institute FOUNDED IN. 1983 LEGAL FORM. Registered association (e.V.) EXECUTIVE DIRECTOR. Dr.-Ing. Volker Heinz MEMBERS. Approx. 113 companies EMPLOYEES. Approx. 120 BUDGET 2009. Approx. 8 million Euro OBJECTIVE. Improvement of efficiency and increase of competitiveness of c ompanies from the food industry MISSION MISSION INNOVATION – Knowledge for superior foods
Organization New structures DIL BUSINESS FIELDS. Providing services for the industry on behalf of direct clients. DIL RESEARCH PLATFORM. Determination of scientific findings, also independently from industrial clients. Development of innovative approaches with the ambition to implement them into attractive products and efficient processes for the industry.
Impact of PEF-treatment (2 kV/cm) on Jona Gold (JG) and Golden Delicious (GD) juice yield using a decanter centrifuge. Juice yield including an eventual transition of solids to juice Pulsed Electric Field Processing Effects on apple tissue
10 t/h installation in German fruit juice company Premium cloudy juice production, using continuous belt press yield increase + 4 to 6 % in comparison to untreated Subsequent enzymatic maceration yield increase + 0 to 2 % Shift to higher production of premium quality first press Energy input: 4 to 6 kJ/kg Pulsed Electric Field Processing Effects on apple tissue
Cell membrane permeabilization Loss of cytoplasma Loss of vitality Treatment conditions Electric field 30 kV/cm Peak current 500 A Pulse repetition ~ 100 Hz Pulsed Electric Field Processing Electrifying microbes
Inactivation of E. coli, L.innocua, S. cerevisae and B. megaterium in ringer solution with an electrical conductivity of 1.25 mS cm -1 after PEF treatment with graphite anode and a field strength of 16 kV cm -1 Inactivation of different microorganisms Pulsed Electric Field Processing Variations in resistance
Impact of processing parameters – process and equipment design Field strength, energy input and temperature Calculated specific energy consumption for a reduction of E. coli in apple juice at different electric field strengths and temperatures as function of treatment temperature (a) and field strength (b). Energy consumption to obtain inactivation 3, 5, 7 and 9 log-cycles at a field strength of 42 kV/cm as function of treatment temperature (c). a b c Pulsed Electric Field Processing Electrifying microbes
Presevation of heat sensitive liquids, such as fruit juices, preparations, beer, cocktail premixes, salsas or sauces Pulsed Electric Field Processing Line setup
Shelf life increase of fresh, non-pasteurized smoothies and other heat sensitive media Pulsed Electric Field Processing Product example fresh juice
Turnkey 5 and 30 kW systems Capacity up to 15 t/h Peak voltage 25 kV Pulse width 4 to 30 µs Pulse repetition 0 to 1.000 Hz 2009 Multiple treatment chambers Pulsed Electric Field Processing Equipment design
PEF Processing Equipment design Power supply Cooling Capacitators, transistors Transformer On/Off button Control panel Oil circulating pump
Pulsed Electric Fields Equipment Design 30 kW Equipment, cotton seed treatment, 15 t/h DN 50 mm
Industrial scale Systems installed Average and peak power Scale Typology Specification Capacity cell disintegration Capacity microbial inactivation Units realized 5 kW 6 MW p Laboratory scale Transformer DN 10 to 30 mm 30 kV max voltage 1500x1150x1600 mm 3 x 400 V, 32 A 1.500 kg/h 200 l/h 20 Germany, Spain, Ireland, USA, Switzerland, Mexico, India, New Zealand, Korea 30 kW 20 MW p Technical / semi-industrial scale Transformer DN 20 to 40 mm 30 kV max voltage 1500x1150x1600 mm 3 x 400 V, 80 A 10.000 kg/h 1.200 l/h 7 UK, Vietnam, Germany, The Netherlands, France, Canada 80 kW 300 MW p (Multiple 160 kW 240 kW) Industrial scale Semi-conductor-based Marx Generator DN 40 to 100 mm 60 kV max voltage 5.000x1.300x2.500 mm 3 x 400 V, 160 A 30.000 kg/h 5.000 l/h 2 Germany, France
Pulsed Electric Fields Conclusion By PEF application an efficient and targeted membrane permeabilization can be achieved An inactivation of microbial cells is obtained The level of inactivation is dependent on processing conditions (electric field strength, specific energy input, temperature) as well as product properties (pH, sugar level) For freshly squeezed juices a superior product quality results The technique is ready for industrial practice