Aufarbeitung von Schlachtblut mit Hilfe gepulster elektrischer Felder

Forschungskreis der Ernährungsindustrie e.V. (FEI)

Godesberger Allee 142-148 53175 Bonn

 

 

AiF-Vorhaben-Nr.: 15585 N Project Short Report

AiF-Mitgliedsvereinigung (MV)

 „Aufarbeitung von Schlachttierblut mit Hilfe gepulster elektrischer Felder (PEF) zur Keimverminderung und nachhaltigem Einsatz für Lebensmittel tierischen Ursprungs“

 Coordination: 

Research Association of the German Food Industry r.S. (FEI), Bonn
Research Institutions: German Institute of Food Technologies, Quakenbrück
Dr. V. Heinz/Prof. Dr. S. Töpfl

University of Veterinary Medicine Hannover, Foundation
Institute for Food Quality and Food Safety
Prof. Dr. G. Klein/Prof. Dr. B. Nowak/Dr. T. von Müffling

Industrial Associations:

Association of the German Meat Industry r.S . (BVDF), Bonn
Association of the German Meat Producers e.V. (VDF), Bonn
VDMA Professional Association of the Food Processing and Packaging Machinery, Frankfurt
Coordinator: P. Brand,
Brand Qualitätsfleisch GmbH & Co. KG, Lohne

Term of Project:

01.12.2008 – 30.11.2010

Grant:

420.050,00 € (Supported by the German Ministry of Economics and Technology (BMWi via AiF/FEI)

Initial Situation:

In Germany approx. 150 million liter of porcine blood result from meat production. At present only a minor part of approx 20 % is used for in food production or as animal feed, though blood is a source of high nutritional and technological value proteins. Due to their functional properties plasma proteins are of particular interest, e.g. in meat industry.

Blood and its fractions offer perfect growth conditions for microorganisms, resulting in a quick microbial growth even during short, chilled storage periods. Prior to a use as food ingredient, the hygiene status of blood has to be evaluated and a low count level guaranteed. At present no suitable decontamination technique for blood is available, which could retain the desired functional properties.

The project has aimed on the development of a microbial decontamination technique for porcine blood, to reduce load of spoilage and pathogenic microorganisms and allow the use of blood as a food ingredient. Pulsed electric fields (PEF) have been applied as a preservation step, with a focus on process product interactions and particularly the effect on protein functionality. Decontaminated blood and its fractions have been used for the product of cooked and scalded meat products to evaluate their technological properties.

Research results:

It has been shown, that by PEF application a reduction of total microbial load as well as spoilage and pathogenic microorganisms was achieved. The specific energy input was identified as a major processing parameter. The results have shown that at an energy input of 75 kJ/kg a decrease of gram negative microorganisms of 3 log-cycles is achieved. Above a level of 125 kJ/kg an inactivation of more than 5 log-cycles was observed for gram negative and positive strains. Dependent on treatment intensity an effect on technological and functional properties was observed. An energy input of 75 kJ/kg resulted in a decrease of denaturation enthalpy of 14 % for plasma and 19 % for blood. Gel hardness was decreased by 30 % for protein gels of treated blood, for plasma an 11 % decrease was observed. The effective viscosity of blood has increased with increasing treatment intensity, whereas no effect on plasma was observed.

In addition the effect of electric field strength (5 – 15 kV/cm) and treatment chamber geometry (co-linear, co-axial, concentric rift) was evaluated in an intensity range of 25 to 165 kJ/kg. Use of a co-linear design resulted in highest inactivation efficiency. When increasing electric field strength a decrease of energy requirement was detected. These elaborated optimum processing conditions have been transferred to blood plasma, subsequently. For plasma the shelf life was increased by a minimum of 4 days at a storage of 4°C, without exceeding a total microbial load of 106 cfu/ml.

Besides successful decontamination, the project was aiming on evaluation of the applicability of PEF-treated blood (fractions) in production of meat products. Cooked and scalded products have been manufactured making used of decontaminated blood and blood plasma. Though minor changes of blood properties have been detected dependent on processing intensity, the use of decontaminated blood products has been possible without limitations. It has been confirmed that treated blood can be used up to a level of 7 % of the total formulation of scalded sausage without technological or sensorial effects

Economic Value:

Within the project a decontamination technique for blood and blood plasma was developed. By its application a reduction of total microbial load of several orders of magnitude was achieved and product safety has been improved.

The technique allows – as exemplarily shown for cooked and scalded meat products – an increased sustainability of meat industry. Making use of by-products of meat production, the economic situation of small and medium sized companies can be significantly improved. In addition, the technique allows a use of blood in other products of animal origin, e.g. in convenience products or as a protein source in special diets. At present a value of 1,30 Euro/kg of pork is assumed (trade category E, January 2011) and a value of 1,45 – 2,65 Euro/kg for meat the value of porcine blood (0,05 Euro/kg) and blood plasma (0,15 Euro/kg) is considerably low. By PEF application additional costs of 0,012 Euro/kg) result. Making use of 3 – 7 % blood products with a low microbial count allows a reduction of raw material costs and an increase of value addition in meat industry.

Publications (Choice):

1. Nowak, B.; Boulaaba, A.: Blut - Proteinlieferant der Zukunft. Längere Haltbarkeit durch PEF-Anwendung. (Bericht) Arbeitskreis der Technologietransferstellen niedersächsischer Hoch-schulen (Hrsg.): Technologie-Informationen: ti; Wissen und Innovationen aus nieder-sächsischen Hochschulen 3; Hannover: Uni Transfer, Gottfried Wilhelm Leibniz Universität, 2009, S. 6
2. Nowak, B., Boulaaba, A., v. Müffling, T. und Klein, G.: Blut - Proteinlieferant der Zukunft. (Posterabstract) Tagungsband 67. FEI-Jahrestagung 2009, (im Druck) (2010).
3. Boulaaba, A.; Nowak, B.; Müffling, T. v.; Hage, N.; Klein, G.: Auswirkungen von PEF (pulsed electric fields)-behandeltem Blutplasma auf qualitative und technologische Parameter von Brüh¬wurst. In: ALPHA Informationsgesellschaft, Deutsche Veterinärmedizinische Gesell-schaft, Bundesverband der beamteten Tierärzte (Hrsg.): Amtstierärztlicher Dienst und Lebens¬mittelkontrolle (Sonderausgabe) 51. Arbeitstagung des Arbeitsgebietes Lebens-mittel¬hygiene: Dreiländertagung; Programm- und Abstract-Band, Garmisch-Partenkirchen, 28.09.-01.10.2010; Lampertheim: ALPHA Informationsgesellschaft, 2010, S. 124 ISSN 0945-3296
4. Wiezorek, T., Heinz, V. and Toepfl, S. (2009) Aufarbeitung von Schlachttierblut mittels gepulster elektrischer Felder (PEF) – Ein Beitrag zur Nachhaltigkeit. Rundschau für Fleischhygiene und Lebensmittelüberwachung 6/2009.

Further Information:

Deutsches Institut für Lebensmitteltechnik e. V.
Prof.-von-Klitzing-Str. 7, D-49610 Quakenbrück
Tel+49 (0)5431.183–0, Fax+49 (0)5431.183–114
E-Mail: s.toepfl@dil-ev.de

 Stiftung Tierärztliche Hochschule Hannover
Zentrum für Lebensmittelwissenschaften
Institut für Lebensmittelqualität und –sicherheit
Bischofsholer Damm 15, D - 30173 Hannover
Tel+49 (0)511/856-7257, Fax+49 (0)511/856-7694
E-Mail: lmqs@tiho-hannover.de

Forschungskreis der Ernährungsindustrie e.V. (FEI)
Godesberger Allee 142-148, 53175 Bonn
Tel 0228/372031
Fax 0228/376150
E-Mail: fei@fei-bonn.de

 
Legal funding reference for publications
„This research project was supported by the German Ministry of Economics and Technology (via AiF) and the FEI (Forschungskreis der Ernährungsindustrie e.V., Bonn). Project AiF 15617 N”.