Name:

Dr. Alexis Pacquit, B.Sc. (Hons), PhD

Contact details

Qualifications

• Ph.D. in Food Biotechnology, HETAC, 2005.
• B.Sc. in Industrial Biology, Institute of Technology Carlow, 1998.
• Diploma in Biology Applied to the Food & Biological Industries, University of Bordeaux 1, 1996.

Project Summary

Given the recent food crisis (BSE, Foot & Mouth, Avian flu), safety assurance has become critically important to rebuild damaged consumer confidence. Within the European Union (EU), food “traceability” is now a legal requirement since the new EU General Food Law² came in effect on 1^st January 2006. This will establish a chain of responsibility throughout the whole food chain, from farm to fork!

Based on EU directive 79/112/EEC, labelling of pre-packed foodstuffs, must include either a date of minimum durability or, when considered highly perishable, a “use before” date¹. However these dates are modelled on the requirement that these foodstuffs are to be maintained at constant chilled or lower temperatures throughout the entire “cold chain”, from production to consumption. This has always been difficult to achieve.

Therefore a Dynamic “Use by” date is the ultimate goal of this project.

In the fisheries industry for example, there is much interest from in developing rapid methods to evaluate real-time freshness of fish and seafood products. Emphasis is on the ones that would reflect and account for the products history and their storage conditions from "harvest-to-home”.

One concept to meet this requirement is that of a smart package that monitors spoilage in fish and seafood products. This has led to the development of simple food quality sensors in the form of on-package sensor spots. These can be inserted as part of adhesive labels on the inside covering lid of the food pack (See figure 1).

Figure 1: Smart Packaging with 4 x replicates sensing labels on the inside 

The sensor is prepared by entrapping within a polymer matrix a pH sensitive dye that responds, through visible colour changes (see Figure 2) to spoilage volatile compounds that contribute to a quantity known as Total Volatile Basic Nitrogen (TVB-N). 

Figure 2: Sensor colour change recorded during industry field trial. The reference "Ref" sensor was placed outside the food pack while the remaining sensors (x3) were placed inside.

Sensor calibration was carried out against standard ammonia gas and laboratory trials on fresh fish filets enabled real time monitoring of their spoilage. The response is monitored with a simple, inexpensive reflectance colorimeter that has been developed “in house”, based on LEDs and a photodetector (See figure 3).

Figure 3: Patented portable colorimeter with interchangeable colour heads

Click here for a short demo of the colorimeter.

System validation was carried out through field trials at seafood processors premises (Oceanpath Ltd, Howth, Ireland) and at a major Irish retailer (Superquinn Ltd, Northside Shopping Centre. Coolock, Dublin 5). Results have shown that the sensor colour change correlates with freshness parameters of packaged fresh fish fillets such as the amines content, indicated by the Total Volatile Basic Nitrogen (TVBN) test, flesh pH and  the microbial load (Total Viable Count (TVC) and Specific Spoilage Organisms (SSOs) - Pseudomonas spp.) at room temperature (19-21°C) (see figure 4) AND at chilled temperature (publication pending).

Figure 4: Correlation of sensor response and changes inbacterial population of fresh cod kept at 20oC over time. (for related publication click here)

Tested fish species, in collaboration with National Food Research institutes such as Teagasc - Ashtown Food Research Centre (Dublin 15) and Bord Iascaigh Mhara - The Irish Fisheries Board (Dun Laoghaire), included common white fish such as cod, whiting, haddock and plaice but also newly introduced under-utilised species such as cardinal and roundnose grenadier.

To enable a seamless insertion onto the wide range of packaging currently used with fresh fish and seafood products, a small, thin and circular plastic sensor holder with 5 hollow barbs was developed (See figure 5). Sensor application is carried out POST-packaging by an easy 1-step push of the operator’s thumb through the packaging covering lid. A circular double-sided adhesive ensures that the pack seal is not compromised. .

Figure 5: Sensor casing dismantled and inserted-through the food pack (outside) on day 1 (Yellow) and day 11 (red)

Contrary to the adhesive labels option, the 5 hollow barbs would allow the encased sensor to be placed on the outside of the tray piercing through the covering lid and keeping separate from the food products. Colour measurements are made through the optically clear plastic.

Take a look at our latest field trials results in processing plants and Supermarkets (Click here). Change in sensor colour over time can be captured using a wireless camera or webcam. A suite of small bespoke programs was designed to capture & process images. A web server hosts a simple java applet allowing user to select "regions of interest" from the captured image, i.e.: the sensor region. The selected regions were processed pixel by pixel to extract the average RGB colour (Click here to see a movie demo). Results can be transferred to web-server in real-time and the user can be notified via email of a particular colour threshold.

Commercialisation oportunities are currently available and enquiries are welcome. For more information, please contact dermot.diamond@dcu.ie.

We acknowledge funding from Enterprise Ireland (EI SC/02/) and Science Foundation Ireland (Adaptive Information Cluster 03/IN.3/1361)

Publications

Publications in peer-reviewed journals

Pacquit A., Lau K. T., McLaughlin H., Frisby J., Quilty B. and Diamond D. Development of a volatile amine sensor for the monitoring of fish spoilage. Talanta, 69 (2006), 515.

Pacquit A., Lau K. T., Farrell A., Frisby J., Quilty B. and Diamond D. Development of a smart packaging for the monitoring of fish freshness. Food Chemistry (Available online July 2006).

Publications at peer-reviewed conferences

Pacquit A., K. Crowley (2007). Use of smart packaging systems for use with fish In Smart Packaging Technologies for Fast Moving Consumer Goods (eds Joe P. Kerry & Paul Butler). Wiley and Sons Ltd.

Pacquit A., Crowley K., Lau K. T. and Diamond D. Real-Time Monitoring of Microbial Spoilage Using Smart Packaging Sensor. Proceedings of IUFoST Conference 2006, Nantes, France (Digital Object Identifier IUFoST2006/702).

Pacquit A., Frisby J., Diamond D.M., Lau K. T., Farrell A., Quilty B. and Diamond D. Development of a smart packaging for the monitoring of fish spoilage. Food Chemistry (Available online July 2006).

K. Crowley, A. Pacquit, K. T. Lau and D. Diamond. A gas-phase colorimetric sensor for the detection of amine spoilage products in packaged fish. Proceedings of IEEE Sensors 2005 conference, Orange County, Irvine, California. The Printing House, Inc. (2005), 754-757. ISBN:0-7803-9057-1.

Pacquit A., Lau K. T., McLaughlin H., Frisby J., Quilty B. and Diamond D. Development of a volatile amine sensor for the monitoring of fish spoilage. Talanta, 69 (2006), 515-520.

A. Pacquit, J. Frisby, K.T. Lau and D. Diamond. Development of a smart packaging for the monitoring of fish freshness. Proceedings of INTRADFOOD-EFFoST Conference 2005, Valencia, Spain (eds P. Fito and F. Toldra). Elsevier, London (2005), 213-216.

Pacquit A., Lau K. T. and Diamond D. Smart packaging for the monitoring of fish freshness. In OPTO-Ireland 2005: Optical Sensing and Spectroscopy,  Proceedings of SPIE Vol. 5826 (eds H.J. Byrne, E. Lewis, B.D. MacCraith, E. McGlynn, J.A. McLaughlin, G.D. O’Sullivan, A.G. Ryder and J.E. Walsh). SPIE, Bellingham, WA  (2005), pp545-550.

Pacquit A., Lau K. T. and Diamond D. Development of a colorimetric sensor for monitoring of fish spoilage amines in packaging headspace. Proceedings of IEEE Sensors 2004 conference, Vienna, Austria (eds D. Rocha, P.M. Sarro and M.J. Vellekoop). The Printing House, Inc. (2004), 365-367. ISBN:0-7803-8693-0.

Pacquit A., Lau K. T., Frisby J., Diamond D.M. and Diamond D. Development of a colorimetric sensor for fish spoilage monitoring based on Total Volatile Basic Nitrogen (TVB-N) measurement. Proceedings of the 34^th WEFTA conference 2004, Lübeck, Germany (eds H. Rehbein, H. Karl, M. Manthey-Karl, J. Oehlenschlager and R. Schubring). FRCFN, Hamburg, Germany (2004), 177-181.

Further Information

Related publications:

1. Liam Byrne, K. Lau, Steve Edwards and Dermot Diamond (2002), Monitoring of headspace total volatile basic nitrogen from selected fish species using reflectance spectroscopic measurement of pH sensitive films. Analyst, 127,1338-1341.
2. Olafsdottir, P. Nesvadba, C. Di Natale, M. Careche, J. Oehlenschlager, S.V. Tryggvadottir, R. Schubring, M. Kroeger, K. Heia, M. Esaiassen, A. Macagnano and B.M. Jørgensen, Trends in Food Science & Technology, 15 (2004) 86. 
3. Gram, L.Huss, H. H. (1996). Microbiological spoilage of fish and fish products. International Journal of Food Microbiology, 33, 121-137.
4. N. Hamada-Sato, U. Kazushige, T. Kobayashi, C. Imada and E. Watanabe, Food control, 16 (2005) 301. 

Links of interest:

1. http://europa.eu.int/comm/fisheries/doc_et_publ/factsheets/legal_texts/sani_en.htm
2. http://www.idtechex.com/