Responsive image

Zeitschriftenbeiträge (peer-reviewed)

2020

Havardi-Burger, N.; Mempel, H.; Bitsch, V. (2020): Driving forces and characteristics of the value chain of flowering potted plants for the German market. European Journal of Horticultural Science 85 (4), S.267-278.
| Volltext

The study investigated the value chain of flowering potted plants supplying the German market and the drivers influencing chain actors. The study builds on strategic and horticultural value chain literature. Data was collected by conducting 20 in-depth interviews with chain actors from different stages in the value chain and analyzed through qualitative content analysis. Results showed that the value chain of flowering potted plants is divided in two pathways due to distinct propagation methods, either generative (seeds) or vegetative (cuttings). Whereas propagation material is generally produced in southern countries, such as Africa and Central America, young plants and potted plants are cultivated within Europe. The paper identified driving forces such as retailer requirements, weather conditions, price pressure and innovations. Furthermore, the study provides an overview of chain activities and processes to help the sector anticipate developments, and support stakeholders in future decisions.

Goisser, S.; Wittmann, S.; Fernandes, M.; Mempel, H.; Ulrichs, C. (2020): Comparison of colorimeter and different portable food-scanners for non-destructive prediction of lycopene content in tomato fruit. Postharvest Biology and Technology 167 (111232), S.1-8.
| Volltext

Lycopene, the red colored carotenoid in tomatoes, has various health benefits for humans due to its capability of scavenging free radicals. Traditionally, the quantification of lycopene requires an elaborate extraction process combined with HPLC analysis within the laboratory. Recent studies focused simpler methods for determining lycopene and utilized spectroscopic measurement methods. The aim of this study was to compare non-destructive methods for the prediction of lycopene by using color values from colorimeter measurements and Vis/NIR spectra recorded with three commercially available and portable Vis/NIR spectrometers, so called food-scanners. Tomatoes of five different ripening stages (green to red) as well as tomatoes stored up to 22 days after harvest were used for modeling. After measurement of color values and collection of Vis/NIR spectra the corresponding lycopene content was analyzed spectrophotometrically. Applying exponential regression models yielded very good prediction of lycopene for color values L*, a*, a*/b* and the tomato color index of 0.94, 0.90, 0.90 and 0.91, respectively. Color value b* was not a suitable predictor for lycopene content, whereas the (a*/b*)² value had the best linear fit of 0.87. In comparison to color measurements, the cross-validated prediction models developed for all three food-scanners had coefficients of determination (r²CV) ranging from 0.92 to 0.96. Food-scanners also can be used for additional measurements of internal fruit quality, and therefore have great potential for fruit quality assessment by measuring a multitude of important fruit traits in one single scan.

Goisser, S.; Mempel, H.; Bitsch, V. (2020): Food-Scanners as a Radical Innovation in German Fresh Produce Supply Chains. International Journal on Food System Dynamics 11 (2), S.101-116.
| Volltext

Originally advertised as tools for end-consumers, portable food-scanners have recently reached a high level of awareness and show potential as instruments for quality assessment along fruit and vegetable supply c hains. The current study explores preferences and concerns of chain actors regarding the implementation of this technology through semi-structured interviews. Results indicate that food-scanners could facilitate quality control at different levels of the fresh produce supply chain by providing fast, non-destructive and objective measurements. Concerns about the application of food-scanners could be identified with respect to potential additional requirements of fruit wholesaler resulting in more pressure on producers. To further a goal-oriented and user-directed development of this new technology, future research should be directed at its impacts on perception of fruit quality along the chain as well as end-consumers’ readiness to use these devices in everyday life.

2019

Mempel, H.; Wittmann, S. (2019): Potential and use of artificial lighting in horticulture. Light and Engineering 2019 (27), S.31-41.

The use of supplemental lighting in horticulture is continuously increasing. Compared to HPS luminaires LED have significant advantages like the possibility of a targeted compilation of the spectrum, the use of dimmable and dynamic adaptable luminaires, the insensitivity to the switching frequency, less heat radiation and the and the high energy efficiency. Experiments with monochromatic lighting show potentials for influencing various quality factors with specialized light spectra in order to reach the targeted plant quality. However, many questions are still open, resulting in a rather low transfer rate of specific lighting strategies in the applied horticulture. Beneficial effects of interlighting were shown in greenhouse experiments and their potentials discussed. In the future higher requirements on plant and fruit quality and a sustainable use of resources will result in a greater importance for specialized lighting strategies and advanced technological solutions.

Goisser, S.; Mempel, H.; Bitsch, V. (2019): Potential Application of Food-Scanners in Fruit and Vegetable Supply Chains and Possible Consequences for the German Market. Proceedings in System Dynamics and Innovation in Food Networks 2019, S.173-181.
| Volltext

Originally advertised as tools for end-consumers, food-scanners have recently gained publicity and show potential as instruments for quality assessment along the fruit and vegetable supply chain. The current study explores preferences and concerns of chain actors regarding the implementation of this technology through semi-structured interviews. Results indicate that food-scanners could facilitate quality control at different levels of the fresh produce supply chain by providing fast, non-destructive and objective measurements. Concerns about the application of food-scanners could be identified with respect to potential additional requirements of trading companies resulting in more pressure on producers. The use of food-scanners by end-consumers is discussed critically. To further a goal-oriented and user-directed development of this new technology, future research should be directed at its impacts on perception of fruit quality along the chain as well as end-consumers’ readiness to use these devices in everyday life.

Goisser, S.; Krause, J.; Fernandes, M.; Mempel, H. (2019): Determination of tomato quality attributes using portable NIR-sensors. 4th International Conference on Optical Characterization of Materials (OCM), March 13th - 14th, 2019, Karlsruhe, Germany, S.1-12.
| Volltext

Each material has its own specific spectral signature independent if it is food, plastics, or minerals. During the conference we will discuss new trends and developments in material characterization. You also will be informed about latest highlights to identify spectral footprints and their realizations in industry.

2018

Goisser, S.; Fernandes, M.; Ulrichs, C.; Mempel, H. (2018): Non-destructive measurement method for a fast quality evaluation of fruit and vegetables by using food-scanner. DGG-Proceedings 8 (13), S.1-5.
Volltext

2016

Mempel, H.; Gabriel, A.; Kersebaum, A.; Bettin, A.; Rath, T.; Ohmayer, G. (2016): WeGa-Student: Entwicklung und Erprobung eines standortübergreifenden B.Sc.-Lehrmoduls zum Thema Prozess- und Produktsicherheit im Gartenbau. DGG-Proceedings (German Society of Horticultural Sciences) 6 (5), S.1-5.
Volltext

Schwend, T.; Prucker, D.; Peisl, S.; Nitsopoulos, A.; Mempel, H. (2016): The rosmarinic acid content of basil and borage correlates with the ratio of red and far-red light. European Journal of Horticultural Science 81, S.243-247.
| Volltext

Rosmarinic acid (RA) and caffeic acid (CA) are potent antixodiants and show antimicrobial activity against many fungal plant pathogens. Their biosynthesis employs enzymes of the phenylpropanoid pathway, a pathway that in mustard is regulated by phytochrome. If RA biosynthesis is regulated by phytochromes one would expect that the RA level correlated with the ratio of red to far-red light. In this paper we tested this hypothesis by growing basil and borage under different ratios of red to far-red light. CA and RA contents were measured with state of the art LC-MS/MS. Regression analysis showed that there is a significant inverse correlation of the ratio of red to far-red light and the content of RA, but not of CA. Hence, we conclude that RA biosynthesis is regulated by phytochrome.

Schwend, T.; Beck, M.; Prucker, D.; Peisl, S.; Mempel, H. (2016): Test of a PAR sensor-based, dynamic regulation of LED lighting in greenhouse cultivation of Helianthus annuus. . European Journal of Horticultural Science 81 (3), S.152-156.
| Volltext

The intensity, and consequently the energy consumption, of light emitting diodes (LEDs) can be regulated. Therefore, LEDs can be implemented in new, dynamic energy saving strategies. Recently it has been shown that a program, which adjusts the intensity of a LED to the current solar PAR, reduced its energy consumption by 20%. The effect of a dynamic LED lighting on ornamental crops has not been tested. In this study we compared the growth of the model plant Helianthus annuus under a dynamic versus a static, control LED lighting. The data of this study show that the dynamic LED consumed 21% less energy than a control LED. However, there was no difference in crop quality or time to anthesis.

Schwend, T.; Kriedel, M.; Prucker, D.; Peisl, S.; Mempel, H. (2016): On the role of the light regime in root development of Euphorbia pulcherrima leafy stem cuttings. European Journal of Horticultural Science (EJHS) 81 (3), S.148-151.
| Volltext

The development of primordial roots of Euphorbia pulcherrima cuttings coincides with a significant increase in photosynthesis. Therefore, Svenson and Davies (1990) suggested that supplementary lighting has no effect on root development of Euphorbia pulcherrima cuttings before primordial roots develop. In this study this hypothesis was experimentally challenged. Cuttings were cultivated with supplementary lighting from the day of sticking and compared to cuttings that were exposed to the same lighting after primordial root development. Our data show that both sets of cuttings developed equally well and both did better than cuttings that were cultivated without supplementary light. Moreover, the data show that light quality had a major impact on root number, length and weight. Therefore, this study confirms the hypothesis of Svenson and Davies (1990) and shows that the positive effect of supplementary lighting is partially mediated by photoreceptors.

2015

Emberger-Klein, A.; Ergül, R.; Mempel, H.; Menrad, K. (2015): Carbon-Footprint-Analysen entlang der Wertschöpfungsketten von Obst und Gemüse an ausgewählten Beispielen sowie Erarbeitung eines entsprechenden Zertifizierungs- und Labellingsystems. Gekürzte Fassung des Schlussberichts an das BMBF (Förderkennzeichen: 17004X11). Hochschule Weihenstephan-Triesdorf (HSWT), Wissenschaftszentrum Straubing, Fachgebiet für Marketing und Management Nachwachsender Rohstoffe (MNR) .
Volltext

Schwend, T.; Prucker, D.; Mempel, H. (2015): Red light promotes compact growth of sunflowers. European Journal of Horticultural Science 80 (2), S.56-61.
| Volltext

Light quality affects plant morphology. Hence, light quality is an important factor in the cultivation of ornamental plants. The recent advances in LED technology allow producers to adjust light quality to manipulate plant growth. For growers of ornamental plants the primary aim regarding plant morphology is to keep plants short and compact with attractive flowers. However, data on the effect of light quality on plant morphology are still sparse. This study provides data on the effect of different LED light regimes on height and fresh weight of shoot and flower, leaf area and compactness of the model plant Helianthus annuus. Regression analysis of these data shows that red light promotes compact growth.

2014

Erguel, R.; Mempel, H. (2014): Berechnung des Carbon Footprints für den Transport von gartenbaulichen Produkten. DGG-Proceedings 4 (10), S.1-5.
Volltext

2012

Kersebaum, A.; Bettin, A.; Mempel, H.; Rath, T.; Ohmayer, G. (2012): WeGa-Student: Hochschulübergreifendes E-Learning Modul im Gartenbau. Landtechnik 67 (5), S.342-345.
| Volltext

In einem gemeinsamen E-Learning-Kurs beschäftigten sich Bachelor-Studierende der Hochschulen Osnabrück und Weihenstephan-Triesdorf sowie der Leibniz Universität Hannover im Wintersemester 2011/2012 mit den spezifischen Anforderungen des Gartenbaus an Qualitätsmanagement und Qualitätssicherung. Ziel der Kooperation der drei Hochschulen war es, die Lehre an allen beteiligten Standorten durch die Bündelung von Kompetenzen zu verbessern. Studierende und Dozenten zogen nach Abschluss des Kurses ein überwiegend positives Fazit.


Zeitschriftenbeiträge

2016

Mempel, H. (2016): Wasserversorgung von Topfpflanzen - vom Produzenten bis zum Verkauf. Taspo (40).

Schwend, T.; Prucker, D.; Haas, H.; Mempel, H. (2016): Wärmestrahlung, LED und Streckungswachstum. Gärtnerbörse (10), S.62-65.
Volltext

Schwend, T.; Prucker, D.; Mempel, H. (2016): Mit Licht hemmen? DEGA Gartenbau (7), S.56-58.
Volltext

2014

Schwend, T.; Prucker, D.; Mempel, H. (2014): Lässt sich das Spektrum von LED-Licht nutzen? DEGA Gartenbau (11), S.54-55.
Volltext

2012

Mempel, H.; Haas, H.; Kohlrausch, F. (2012): Gesunde Poinsettien sind lagerfähig und haltbar. Gärtnerbörse 112 (8), S.52-56.

2011

Mempel, H.; Haas, H.; Kohlrausch, F. (2011): Strategien zur Einsparung von Energie ohne Qualitätsverluste. Gärtnerbörse 111 (10), S.38-41.

2010

Mempel, H.; Haas, H.; Kohlrausch, F. (2010): Cool morning ….warm evening. Gärtner + Florist 15 (12), S.22-24.

Haas, H.; Kohlrausch, F.; Mempel, H. (2010): Poinsettien: Energie sparen ohne Qualitätsverluste. Gärtnerbörse (4), S.29-31.

Haas, H.; Kohlrausch, F.; Mempel, H. (2010): Lassen sich verkaufsfertige Poinsettien kühl lagern? Gärtnerbörse (6), S.40-42.


Beitrag in Monografien, Sammelwerken und Schriftenreihen (peer reviewed)

2018

Herppich, W.; Mempel, H.; Geyer, M. (2018): Carrot water relations during postharvest: effects on internal and external product quality. Integrated View of Fruit and Vegetable Quality. eBook Published January 2018, S.64-72.
Volltext


Beiträge in Monografien, Sammelwerken und Schriftenreihen

2018

Goisser, S.; Fernandes, M.; Mempel, H. (2018): Zerstörungsfreie Messmethode zur schnellen Qualitätsbewertung und Haltbarkeitsabschätzung von Lebensmitteln mit Hilfe von Food Scannern. Tagung der Deutschen Gartenbauwissenschaftlichen Gesellschaft. BHGL-Schriftenreihe 33, S.34.

2017

Havardi-Burger, N.; Mempel, H.; Bitsch, V. (2017): Supply chain of bedding plants and pot plants in Germany. DGG Proceedings 2017 7/2017 (12), S.1-5.
Volltext


Wissenschaftliche Poster

2018

Suhl, J.; Schmidt, U.; Mempel, H.; Akyazi, G.; Dannehl, D. (2018): Entwicklung eines sensorbasierten intelligenten Gewächshaus-Managementsystems. BHGL Schriftenreihe Band 33 - 2018 33, S.151.

Wittmann, S.; Mempel, H. (2018): Anwendung der Chlorophyllfluoreszenz zur Darstellung von Salzstress an Lycopersicon esculentum L. 'Tastery'. Tagung der Deutschen Gartenbauwissenschaftlichen Gesellschaft. BHGL-Schriftenreihe 33, S.150.

Wittmann, S.; Mempel, H. (2018): Auswirkung einer Mono- und Polychromatischen Belichtung auf den Wuchs und die Photosynthese von Lactuca Sativa. Tagung der Deutschen Gartenbauwissenschaftlichen Gesellschaft. BHGL-Schriftenreihe 33, S.149.

2017

Schwend, T.; Mühlmann, C.; Beck, M.; Prucker, D.; Mempel, H. (2017): Regulation of greenhouse lighting with a PAR sensor. BHGL-Tagungsband 31/2015, S.119.

Havardi-Burger, N.; Mempel, H.; Bitsch, V. (2017): Supply chain analysis of bedding plants and pot plants in Germany. 51. DGG & BHGL Jahrestagung 2017.
Volltext

2015

Schwend, T.; Prucker, D.; Nitsopoulos, A.; Mempel, H. (2015): Correlation of rosmarinic acid content of basil with the ratio of far-red:red light. BHGL-Tagungsband 31/2015 (31), S.121.

2013

Hauser, B.; Mempel, H.; Baur, M.; Haas, H.; Kohlrausch, F.; Prucker, D. (2013): Einfluss von LEDs auf das Wachstum und Blühverhalten von Beet- und Balkonpflanzen. DGG Tagung, Bonn, 27.02.-02.03.2013.

2012

Hauser, B.; Mempel, H.; Haas, H.; Kohlrausch, F. (2012): Strategies for saving Energy without Loss of Plant Quality. 2nd Symposium on Horticulture in Europe, Angers, Frankreich, 01.-05.07.2012.

2011

Mempel, H.; Haas, H.; Kohlrausch, F. (2011): Energiekosteneinsparung bei der Produktion von Poinsettien durch vorgezogenen Anbau und anschließender Lagerung. DGG-Tagung Hannover, 23.-26.02.2011.


Presseberichte und Medienbeiträge

2019

Wolff, J.; Mempel, H. (2019): Die Senkrechtpflanzer. Zeitungsartikel: Die Zeit, von Justin Wolff 2019 (45).
| Volltext

Ackerfläche wird knapp, doch Salat lässt sich gestapelt in Schränken und Regalen züchten. Ist die Technologie schon reif für die Produktion in großen Mengen? 

Newsmeldung HSWT, .; Mempel, H. (2019): Expertin der HSWT beantwortet häufig gestellte Fragen zum Thema Vertical Farming bzw. Indoor Farming. Forschungs-News HSWT, 09.05.2019.
Volltext


Sonstige Veröffentlichungen

2016

Mempel, H.; Schwend, T.; Prucker, D. (2016): Energieeinsparung und Effizienzsteigerung in der gärtnerischen Produktion durch LED-Belichtungssysteme . zweiseitig.

2015

Mempel, H. (2015): Wasserversorgung von Topfpflanzen vom Produzenten bis zum Verkauf .

2014

Schwend, T.; Prucker, D.; Mempel, H. (2014): Der Einfluss von LED-Licht auf den Rosmarinsäuregehalt in Basilikum. Infodienst Weihenstephan, Dezember 2014 / Januar 2015.
Volltext

Mempel, H.; Menrad, K. (2014): Carbon-Footprint-Analysen entlang der Wertschöpfungsketten von Obst und Gemüse.

2013

Prucker, D.; Mempel, H. (2013): Einfluss der verschiedenen Wellenlängen einer LED-Belichtung auf das Pflanzenwachstum. Infodienst Weihenstephan, April 2013.
Volltext


Vorträge

2019

Goisser, S.; Mempel, H. (2019): Mobile Nahinfrarottechnik im Post-Harvest-Management. Vortrag im Forum "Auf einer Wellenlänge" des Forschungsprojekts "Food-Scanner" am 26.10.2019 in Freising.

Goisser, S.; Mempel, H. (2019): Können Food-Scanner Lebensmittelverluste reduzieren? "Zu gut für die Tonne" - Themenabend zur Lebensmittelverschwendung am 14.05.2019 in Ansbach.

Goisser, S.; Krause, J.; Fernandes, M.; Mempel, H. (2019): Determination of tomato quality attributes using portable NIR-sensors. 4th International Conference on Optical Characterization of Materials (OCM), March 13th - 14th, 2019, Karlsruhe, Germany.

Goisser, S.; Mempel, H.; Bitsch, V. (2019): Potential applications of food-scanners in fruit and vegetable supply chains and possible consequences for the German market. 13th International European Forum (Igls-Forum) on System Dynamics and Innovation in Food Networks, February 18th - 22nd, 2019, Garmisch-Partenkirchen, Germany.

2018

Goisser, S.; Mempel, H. (2018): Der Einsatz portabler Mini-Sensoren vom Erzeuger bis zum Verbraucher. Deutscher Obst & Gemüsekongress (20.-21.09.2018 Düsseldorf).

Mempel, H.; Goisser, S. (2018): Fruchtqualität auf Knopfdruck – Nachernteverluste im Gartenbau. Vortrag beim 1. Bayerisches Symposium gegen Lebensmittelverschwendung – Du bist, was du aufisst!“ Fachsymposium 2018 .
Volltext

Mempel, H.; Goisser, S. (2018): Qualitätsveränderungen bei pflanzlichen Lebensmitteln. Vortrag beim Fachkongress "Lebensmittel retten 4.0 - Innovative Verfahren zur Reduzierung von Lebensmittelverlusten" am 16.05.2018 im Bayerischen Staatsministerium für Ernährung, Landwirtschaft und Forsten.
Volltext

2016

Mempel, H. (2016): Technische Anpassungspotentiale für gärtnerische Produktionssysteme. Impulsvortrag auf dem HortInnova Expertenworkshop im Forschungsfeld "Anpassung gartenbaulicher Produktionssysteme an sich ändernde Herausforderungen". Vortrag an der Universität Bonn am 15.06..

Mempel, H. (2016): Innovationen in der der Unterglasproduktion - Trends in Deutschland und bei unseren Nachbarn. Vortrag auf der 3. INDEGA Fachgruppentreffen in Grünberg am 14.04.16.

2015

Schwend, T.; Prucker, D.; Mempel, H. (2015): LED – the key for product design. Vortrag auf der Fruit Logistica Berlin, Februar 2015.
Volltext

Kersebaum, A.; Mempel, H.; Bettin, A.; Rath, T. (2015): WeGa Student: Ein Leuchtturmprojekt wird Routine. BHGL - Schriftenreihe Band 31, 2015 (31), S.71.

Bliedung, S.; Mempel, H.; Trierweiler, B. (2015): Ermittlung des optimalen Genusszeitraums von vorgereiften Kiwifrüchten. BHGL - Schriftenreihe Band 31, 2015 (31), S.67.

Ergül, R.; Mempel, H. (2015): Dynamischer Product Carbon Footprint von Obst und Gemüse – Lösungsansatz zur Ermittlung der Variabilität in den gartenbaulichen Wertschöpfungsketten. BHGL - Schriftenreihe Band 31, 2015 (31), S.60.

Schwend, T.; Prucker, D.; Mempel, H. (2015): Red light promotes compact growth of sunflowers. BHGL - Schriftenreihe Band 31, 2015 (31), S.56.