Re-investigation on odour thresholds of key food aroma compounds and development of an aroma language based on odour qualities of defined aqueous odorant solutions

Literature data on odour thresholds of volatile food constituents, and, in particular on their odour quality, may differ significantly. In order to obtain more reliable sensory data, the odour thresholds of eighty-four compounds previously characterised as key food odorants were re-evaluated and compared to literature results. In addition, the odour thresholds of ten odorants are reported here for the first time. On the basis of a distinct protocol, also the aroma attributes of the odorants were evaluated in order to define an aroma language, which can be used for specific purposes, e.g., training of panellists for GC-Olfactometry.     

1. Treffen des wissenschaftlichen Netzwerkes zur Authentizitätsprüfung von Lebens- und Futtermitteln

Authentication of food and feed covers a broad range of topics, matrices, analytical techniques and research approaches. To address future challenges of authenticity testing, cooperation among public institutes becomes more and more important. In this perspective, the Federal Institute for Risk Assessment (BfR) organized a German-wide meeting (translated title: Status quo of authenticity testing of food and feed – methods for routine analysis and research approaches) to improve scientific exchange opportunities among expert of public research institutes and regulatory bodies. Experts of federal institutes, federal state surveillance bodies and universities were invited by the BfR to report about their experiences and activities related to authenticity testing of food and feed. The scientific exchange within this up to date research field was successfully promoted by the development of an expert network with this BfR event.     

Exposing Differences in Monomer Exchange Rates of Multicomponent Supramolecular Polymers in Water

The formation of multicomponent and bioactive supramolecular polymers is a promising strategy for the formation of biomaterials that match the dynamic and responsive nature of biological systems. In order to fully realize the potential of this strategy, knowledge of the location and behavior of bioactive components within the system is crucial. By employing synthetic strategies to create multifunctional monomers, coupled with FRET and STORM techniques, we have investigated the formation and behavior of a bioactive and multicomponent supramolecular polymer. By creating a peptide‐dye‐monomer conjugate, we were able to measure high degrees of monomer incorporation and to visualize the equal distribution of monomers within the supramolecular polymer. Furthermore, by tracking the movement of monomers, we uncovered small differences in the dynamics of the bioactive monomers.     

Evidence for Behavioral Attractiveness of Methoxylated Aromatics in a Dynastid Scarab Beetle-Pollinated Araceae

Many plants attract their pollinators with floral scents, and these olfactory signals are especially important at night, when visual signals become inefficient. Dynastid scarab beetles are a speciose group of night-active pollinators, and several plants pollinated by these insects have methoxylated aromatic compounds in their scents. However, there is a large gap in our knowledge regarding the compounds responsible for beetle attraction. We used chemical analytical analyses to determine temporal patterns of scent emission and the composition of scent released from inflorescences of Philodendron selloum. The attractiveness of the main components in the scent to the dynastid scarab beetle Erioscelis emarginata, the exclusive pollinator of this plant, was assessed in field biotests. The amount of scent increased rapidly in the evening, and large amounts of scent were released during the activity time of the beetle pollinators. Inflorescences emitted a high number of compounds of different biosynthetic origin, among them both uncommon and also widespread flower scents. Methoxylated aromatic compounds dominated the scent, and 4-methoxystyrene, the most abundant compound, attracted E. emarginata beetles. Other compounds, such as (Z)-jasmone and possibly also the methoxylated aromatic compound 3,4-dimethoxystyrene increased the attractiveness of 4-methoxystyrene. Methoxylated aromatics, which are known from other dynastid pollinated plants as well, are important signals in many scarab beetles in a different context (e.g., pheromones), thus suggesting that these plants exploit pre-existing preferences of the beetles for attracting this group of insects as pollinators.     

An overview of work analysis instruments for hybrid production workplaces

With increasing technological improvements, production processes are becoming more and more automated. Nevertheless, full automation is improbable in the medium term since human abilities cannot yet be completely replaced. Therefore, it is likely that so-called hybrid human–robot teams will assume the future production. This raises questions regarding the shaping of future production and the effects it will have on the employees, workstations, and the companies as a whole. The project “Work in the Industry of the Future” (ARIZ) addresses the entirely new cooperative relationship between man and technology in the Industry 4.0 and its impact on opportunities for the work force. To derive the requirements and effects of hybrid workplaces, an initial work analysis of existing workplaces with varying levels of technological enhancement (manual workplaces, workplaces with co-existing robots and fully automated workplaces) will be conducted. Multiple standardized work analysis instruments that vary in method, duration, level of analysis, and recorded characteristics already exist. This paper gives an overview of an assortment of these methods that can be used in production.     

A new UV sensitive positive resist for X-ray masks manufacture

LIGA is a well-established process to fabricate metallic micro parts with high resolution, high precision and very low sidewall roughness by means of X-ray lithography and electroplating. The availability of a precise X-ray mask is a precondition for the final precision of the manufactured micro parts. Typical mask substrate materials, e.g. beryllium, carbon based foils, Si₃N₄ or SiC show different disadvantages such as low X-ray transparency or high toxicity or high prices or low conductivity or high thermal expansion or surface porosity causing X-ray scattering. For the fabrication of X-ray masks, PMMA with its unique features such as high aspect ratio patterns with high precision, exhibits low sensitivity and the layers preparation is not easy. SU-8, an epoxy-based UV and X-ray sensitive, chemically amplified, negative tone photoresist exhibits high aspect ratio patterns with vertical sidewalls. The difficult remove of the resist after the electroplating process significantly hinders the inspection of the fabricated X-ray mask. We present the use and suitability of an UV sensitive, chemically amplified, viscous, aqueous-alkaline developable, and easy removable positive tone photoresist, XP mr-P 15 AV, exhibiting high aspect ratio patterns with vertical sidewalls for the fabrication of X-ray masks by means of UV lithography on vitreous carbon substrates.     

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