The 10 most recently published documents
Taking the transdisciplinary research study “Green fingers for a climate resilient city”, funded by the German Ministry of education and research (BMBF), as an example, this paper follows the hypothesis that processes of landscape planning and designing multifunctional green spaces and processes of co-creation need to be combined to stimulate climate resilient city transformation. The findings are that efforts to combine these processes benefit from making complex climate-resilient city planning accessible for people of different professional backgrounds. The paper showcases how storytelling (Schmidt 2019), mapping (Langner 2009) and guided walks (Schultz 2019) are means to mutually engage with, perceive and understand multifunctional green spaces, inspire ownership, and build capacity for the city’s climate-resilient transformation.
Shockwaves are mechanical pressure pulses generated in liquids and gases. Based on the principles of acoustics, shockwavescan propagate through fluids such as water. At interfaces of materials with different acoustic impedances, mechanical energy is dissipated, and disintegration of biological tissue can be achieved. Physical properties as well as technical requirements for shockwave generation by electrohydraulic, electromagnetic or piezoelectric energy conversion have been reported in the literature. The use of electrohydraulic shockwaves for food treatment is an emerging food processing technology, where a lack of scientific and technical knowledge has limited further advancements in process and equipment design. In scientific literature, single aspects required for process description are available, e.g., in metallurgy, mining, air purification or particle accelerators, but their combination toward a combined model is required to characterize underlying mechanisms of action. In food, most of the studies have focused on shockwave technology for treatment of meat cuts with the purpose of reducing aging time, softening of tissue and improving its tenderness. Other applications of the shockwave technology could expand to biological inactivation, targeted texture modifications and improving extractive and refining processes in agriculture industries. Total processing costs are estimated in a range of a few Euros per ton of product. Despite being a promising alternative to existing processes used for these purposes, the application of shockwave in the food industry is limited to date to research on pilot-scale prototypes.
PEF is an innovative technology to extend the shelf life of fresh liquid food products, mainly juices, with minor impact on the quality. Many lab scale studies have been published, indicating the great potential of PEF for the juice industry. For industrial realization, the PEF systems have been adapted to the industrial requirements, establishing HACCP and hygienic design concept. Important process parameters have been identified from research and integrated in industrial PEF processes. Juice producers are now able to use PEF for their production lines.
This chapter presents the mechanism of the enhancement of freezing by means of ultrasound (US). It has been demonstrated that the effects of US are a rather complex issue. In theory, ultrasound creates cavitation bubbles throughout the volume of the product, which promotes nucleation of the ice and crushes the crystals already present in food. They can also enhance convective heat transfer to the cooling media, thereby accelerating freezing. Moreover, it has been shown that ultrasound reduces the degree of supercooling before nucleation in frozen food. Additionally, numerous experimental studies indicate that ultrasound assisted freezing is a good method to achieve homogenous crystallizations, reduce the deteriorating effect of freezing on food, and thus improve quality after thawing.