6533b839fe1ef96bd12a57ac

RESEARCH PRODUCT

Identification of markers that can be recognised using spectroscopic sensors and which reflect key stages in the cooking of meat and fish

subject

description

One of the purposes of the Opticook project is to install spectroscopic sensors in ovens, so equipping them with non intrusive tools allowing following cooking process of meat and fish. The hypothesis on which sensors were developed was: are muscular proteins proper probes to discriminate among several cooking degrees? Thus, at the beginning of the project several tools were used to characterise effect of several cooking degrees on macroscopic properties (texture and colour) of beef, chicken and cod fillet samples. Following, calorimetry and spectroscopic techniques were used to study transformations at molecular scale. In particular, visible spectroscopy followed denaturation of haemproteins observing their evolution from oxy to met state. Colour change was observed between 50 and 75 °C. Middle infrared and fluorescence spectroscopies were used to observe evolution of fibrillar proteins which are associated with meat texture changes. One of myofibrils, myosin, was purified from chicken breast and was studied depending on temperature by fluorescence spectroscopy. Observations showed evolution of protein structure occurred around 50 °C. At microscopic scale, low field NMR (spin echo and gradient field configurations) and neutron tomography were used to observe morphology changes and juice release on beef samples according to cooking degree. 3D image analysis and NMR data showed morphology and fibre density changes at high temperature.We associated the two approaches (molecular and microscopic) in the last part of the research. So coupled measures were realised by combining neutron imaging and spectroscopy techniques during cooking process on beef slices by Opticook oven. Coupled measures allowed following morphology evolution because of fibre contractions, juice migration and colour modification as well associated to haemprotein denaturation. In conclusion, it is possible to follow cooking process of meat and fish by following several spectroscopic signatures (fluorescence and visible ones) of matrix own probes: myosin, collage and haemproteins.