• Treffer 57 von 78
Zurück zur Trefferliste

Prozesskontrolle der Qualität von frischem Obst und Gemüse mit Hilfe eines Multigas-Sensors

Process Control in Fresh Fruit and Vegetable by Means of Multigas Analysis

  • Zur Messung und Kontrolle der Qualität von Obst und Gemüse wurde ein portables einsetzbares zerstörungsfreies Messverfahren auf der Basis der Multigas-Analyse entwickelt und hinsichtlich seiner Eignung untersucht, die qualitätsrelevanten Gaswechselprozesse zwischen Produkt und umgebender Atmosphäre zu erfassen. Ziel war es eine online-fähige Methode zur Produktzustandsanalyse in den Vor- und Nachernteprozessen der Versorgungskette gartenbaulicher Kulturen zu erhalten.
  • In the frame of this project a portable multigas sensor for monitoring the quality of fresh fruit and vegetable was developed and tested regarding the sensor's sensitivity for recording quality-relevant changes in gas exchange rates of the product. The aim was to obtain an innovative tool for online analysis of the physiological stage of horticultural products feasible for pre- and post-harvest applications. The working tasks were performed in two interlaced working programmes (separate projects) for (i) the development and construction of the microelectronic sensor technology and (ii) the testing and evaluation of this sensor technology for the quality assessment in fresh fruit and vegetable. At the ATB, preliminary investigations in the development of a multigas sensor system were accomplished regarding the data organisation and analysis. In parallel a suitable laboratory set-up with the possibility of regulated gas conductance in an air-conditioned cuvette system was set-up. The response of 7 differently doped semiconductors wasIn the frame of this project a portable multigas sensor for monitoring the quality of fresh fruit and vegetable was developed and tested regarding the sensor's sensitivity for recording quality-relevant changes in gas exchange rates of the product. The aim was to obtain an innovative tool for online analysis of the physiological stage of horticultural products feasible for pre- and post-harvest applications. The working tasks were performed in two interlaced working programmes (separate projects) for (i) the development and construction of the microelectronic sensor technology and (ii) the testing and evaluation of this sensor technology for the quality assessment in fresh fruit and vegetable. At the ATB, preliminary investigations in the development of a multigas sensor system were accomplished regarding the data organisation and analysis. In parallel a suitable laboratory set-up with the possibility of regulated gas conductance in an air-conditioned cuvette system was set-up. The response of 7 differently doped semiconductors was tested at relevant concentrations of pure substances of native fruit compounds as well as on fresh products. Four layers were selected with respects to its sensitivity. Correction algorithms were compiled regarding the temperature influence on the specific layers. In the laboratory, experimental series were carried out on different aromas as well as CO2 and C2H4 with such adapted system. In the process of the laboratory tests, sensor and application requirements were pointed out for the practical application. These were used for the construction of a portable operating model of the sensor system by the industrial partner ahler sensors. A SQL data base was developed at the ATB, in order to make the structured data acquisition and data inquiry possible for the system calibration and its validation. Recorded data can be saved and pre-processed with semi-automatically routines, whereby characteristic data areas are selected and loaded into Matlab. Routines for multivariate data analysis as well as for the setting up neural nets have been enabled for the calibration on the concentration of a pure substance or a specific product maturity stage. Particularly, extensive investigations were accomplished on different ethylene concentrations, since the ethylene production in climacteric fruit rises exponentially after decay as well as in advanced maturity stages, thus representing a characteristic marker for the product condition. Pure ethylene subjected to the sensor was detected with high signal to noise ratio in the concentration range from 20 to 100 ppm. This range corresponds to the ethylene delivery of one mature apple. In further experiments gas samples were taken from the headspace of horticultural products as apples, strawberries, and carrots at different degrees of maturity and after microbe contamination, whereby comparative measurements by gas chromatography took place regarding the actual ethylene and aroma concentration. The data processing by pattern recognition procedures showed only a very weak sensitivity of the sensor for the recognition of ethylene in gas mixtures with native and artificial fruit volatiles. Zude, Hielscher-Tölzer, Wulf 66 Extensive experimental series were carried out with priority on fresh apples, bananas and carrots to find characteristic finger prints of different maturity stages. Measuring protocols were adapted on the fruit and vegetable properties for the acquisition of reference data regarding the product gas exchange as the fruit respiration rate, transpiration rate, chromatographic analysis of the C2H4 and aroma evolution by means of solid phase microextraction (SPME, Supelco). Further characterisation of the physiological product stage was carried out by analysis of starch hydrolysis and texture properties.zeige mehrzeige weniger

Volltext Dateien herunterladen

Metadaten exportieren

Weitere Dienste

Teilen auf Twitter Suche bei Google Scholar
Metadaten
URN:urn:nbn:de:kobv:186-opus-55791
ISSN:0947-7314
Schriftenreihe (Bandnummer):Bornimer Agrartechnische Berichte (50)
Dokumentart:Einzelveröffentlichung / Monografie
Sprache:Deutsch
Erscheinungsjahr:2005
Urhebende Körperschaft:Leibniz- Institut für Agrartechnik Potsdam - Bornim e.V. (ATB)
Sonstige Beteiligte Körperschaft:Bundesministerium für Bildung und Forschung (BMBF) ; Forschungszentrum Jülich GmbH (PTJ)
Datum der Freischaltung:26.02.2014
Freies Schlagwort / Tag:Gemüse; Obst; Prozesskontrolle; Qualität
Control; Fruits; Process; Quality; Vegetables
Landkreise / Gemeinden:Potsdam / Potsdam, Stadt
DDC-Klassifikation:6 Technik, Medizin, angewandte Wissenschaften / 63 Landwirtschaft / 630 Landwirtschaft und verwandte Bereiche
Kollektionen :Institutionen / Leibniz-Institut für Agrartechnik und Bioökonomie e.V. (ATB) / Bornimer Agrartechnische Berichte
Lizenz (Deutsch):Es gilt das deutsche Urheberrecht.