Responsive image


Case study: A sensory training course as an ignition spark for a remarkable sector development in small and medium sized Bavarian distilleries. ISEKI 2016

Höfer, C.; Rehmann, D. (2016)

CYTA - Journal of Food.


Wood finished fruit spirits: time-dependent colour development and product colour preferences amongst professionals

Höfer, C.; Bauer, B.; Zimmer, T.; Methner, F.; Rehmann, D. (2016)

Eurosense.


Evaluation of the cellular antioxidant activity of berry juices and its improvement with mash enzyme and heat treatments

Bender, C.; Killermann, K.; Rehmann, D.; Weidlich, H. (2016)

30th EFFoST International Conference, Wien.


Effect of mash enzyme and heat treatments on the cellular antioxidant activity of black currant (Ribes nigrum), raspberry (Rubus idaeus), and blueberry (Vaccinium myrtillus) juices

Bender, C.; Killermann, K.; Rehmann, D.; Weidlich, H. (2016)

CyTA - Journal of Food 15 (2), S. 277-283.
DOI: 10.1080/19476337.2016.1247914


Open Access
 

The aim of this study was to determine the effect of mash enzymatic maceration and heating treatments before pressing on the antioxidant activities in selected berry juices. Total phenolic contents were determined by the Folin–Ciocalteau assay, antioxidant activities were determined by means of the oxygen radical absorbance capacity (ORAC) assay, and the intracellular antioxidant potentials were determined through the cellular antioxidant activity (CAA) assay. Blueberry juices exhibited the highest antioxidant activity, followed by black currant and raspberry juices. The mash enzyme treatment with Pectinex® Ultra Color enzyme preparation, improved the antioxidant activities in vitro. ORAC values correlated with CAA values (R2 = 0.91) and a slightly positive correlation was observed between Folin–Ciocalteau and CAA assays (R2 = 0.56). The findings support the observation that the mash enzymatic treatment of macerated fruits enhances their antioxidant activity. Considering the chemical assays (ORAC and total phenolic content), a combined treatment with heating to 85°C followed by mash enzymatic treatment was the most effective. Considering a biological model through the CAA assay, however, a comparable improvement in antioxidant activity resulted from the enzymatic and the combined treatments. Overall, the data showed that maceration enzymatic treatment improves the intracellular antioxidant activity in HepG2 human cells. To the best of our knowledge, this is the first report on the effect of the antioxidant potential of mash enzymatic and heating treatments assessed by means of a cellular approach.

mehr

Coating techniques for glass beads as filter media for removal of manganese from water

Rose, P.; Hager, S.; Glas, K.; Rehmann, D.; Hofmann, T. (2016)

Water Science and Technology: Water Supply 17 (1), S. 95-106.
DOI: 10.2166/ws.2016.116


Open Access
 

Dry as well as wet coating techniques were developed to coat glass beads as filter media to remove manganese from water. For dry coating, powdered manganese oxide ore was fixed on the media surface. Wet coating was achieved by depositing synthetic manganese oxides onto the bead surface. The media were characterized by electron microscopy as well as by testing the removal of Mn2+ in a continuous stirred tank reactor. Image analysis of microscopic pictures illustrated that the surface area could partly be coated by powdered material using dry coating methods, whereas complete coverage was achieved using wet coating approaches. With regard to dry coating techniques, Mn sorption uptake was higher for the adhesively dry coated glass beads than for beads where a binding agent was used. The wet coating column approach proved to be more successful than the coating of beads in a stirred tank reactor. Mn removal capability of the beads increased with higher reactant concentrations during coating. Oxide-coated glass beads applied in filter systems have the potential to improve conventional demanganization processes.

mehr

Q = m c ΔT – Grundlage zur Steuerung des Stoffaustauschs von auf Verdunstung basierenden Prozessen (Addendum)

Feilner, R.; Werner, F.; Rehmann, D.; Methner, F.; Scheuren, H. (2015)

Chemie Ingenieur Technik 87 (7), S. 1014.
DOI: 10.1002/cite.201590051

mehr

Q = m c ΔT – Grundlage zur Steuerung des Stoffaustauschs von auf Verdunstung basierenden Prozessen

Feilner, R.; Werner, F.; Rehmann, D.; Methner, F.; Scheuren, H. (2015)

Chemie Ingenieur Technik 87 (5), S. 583-589.
DOI: 10.1002/cite.201400129

mehr

Prof. Dr. Dirk Rehmann


Hochschule Weihenstephan-Triesdorf

Fakultät Gartenbau und Lebensmitteltechnologie
Am Staudengarten 10
85354 Freising