2014, Hassenberg, Karin, Herppich, Werner B., Praeger, Ulrike

Der Markt für abgepackte verzehrfertige Frischsalate ist in den vergangenen Jahren stark gewachsen. Für die Herstellung von mikrobiologisch unbedenklichen Produkten wurde der Zusatz von Chlordioxid (ClO2) zum Waschwasser auf sein Potenzial zur Minimierung relevanter humanpathogener Mikroorganismen getestet. Dabei wurden auch wichtige Parameter der Produktqualität, wie z. B. Farbe und Inhaltsstoffe, berücksichtigt. Eine ClO2-Behandlung ermöglicht es, die Konzentration von Mikroorganismen im Waschwasser um 5 bis 6 log-Einheiten zu reduzieren, abhängig vom chemischen Sauerstoffbedarf (CSB-Wert). Farbe und Vitamin-C-Gehalt der Salatblätter werden von der Behandlung nicht beeinflusst. Demnach ist ClO2 zur Hygienisierung von Salatwaschwasser geeignet.

2019, Rux, Guido, Efe, Efecan, Ulrichs, Christian, Huyskens-Keil, Susanne, Hassenberg, Karin, Herppich, Werner B.

Processing, especially cutting, reduces the shelf life of fruits. In practice, fresh-cut fruit salads are, therefore, often sold immersed in sugar syrups to increase shelf life. Pre-processing short-term hot-water treatments (sHWT) may further extend the shelf life of fresh-cuts by effectively reducing microbial contaminations before cutting. In this study, fresh-cut ‘Braeburn’ apples, a major component of fruit salads, were short-term (30 s) hot water-treated (55 °C or 65 °C), partially treated with a commercial anti-browning solution (ascorbic/citric acid) after cutting and, thereafter, stored immersed in sugar syrup. To, for the first time, comprehensively and comparatively evaluate the currently unexplored positive or negative effects of these treatments on fruit quality and shelf life, relevant parameters were analyzed at defined intervals during storage at 4 °C for up to 13 days. Compared to acid pre-treated controls, sHWT significantly reduced the microbial loads of apple slices but did not affect their quality during the 5 day-standard shelf life period of fresh-cuts. Yeasts were most critical for shelf life of fresh-cut apples immersed in sugar syrup. The combination of sHWT and post-processing acid treatment did not further improve quality or extend shelf life. Although sHWT could not extend potential maximum shelf life beyond 10 d, results highlighted the potentials of this technique to replace pre-processing chemical treatments and, thus, to save valuable resources.

2010, Geyer, Martin, Hassenberg, Karin, von Haselberg, Christiane

[no abstract available]