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In Mediterranean countries, and in Sardinia in particular, durum wheat is traditionally used for bread production and modern cultivars have gradually replaced the use of old landraces due to the poor technological quality of the latter. However, recent escalation in customer demand for old varieties thanks to an appreciation of their nutritional properties, as well as ecological issues, has led to the need for technological improvements able to enhance the rheological performance of the old varieties to support their diffusion. The aim of this study was to assess whether the baking performance of an Old Italian wheat cultivar, Russello wheat, could be improved through the addition of different hydrocolloids (methylcellulose, guar, psyllium, xanthan and tara). The effects of two different concentrations (0.5% and 1%) of each hydrocolloid on the rheological properties, pasting, fermentation and microstructural properties of dough were assessed, and the results compared with those obtained using a modern durum wheat cultivar flour. Significant differences were found in the dough obtained with hydrocolloids. In particular, dough extensibility was increased with 1% psyllium or xanthan gum, whereas the gas retention coefficient was increased with all hydrocolloids. The pasting properties were modified via an increase in the final viscosity and setback value compared with control semolina (with the exception of methylcellulose); this resulted in a more homogeneous dough structure with a compact appearance and the absence of any deep interruptions in the gluten network as revealed by scanning electron microscopy.

Grape juice can be easily contaminated with ochratoxin A (OTA), one of the known mycotoxins with the greatest public health significance. Among the different approaches to decontaminate juice from this mycotoxin, microbiological methods proved efficient, inexpensive and safe, particularly the use of yeast or yeast products. To ascertain whether immobilisation of the yeast biomass would lead to successful decontamination, alginate beads encapsulating Candida intermedia yeast cells were used in our experiments to evaluate their OTA-biosorption efficacy. Magnetic calcium alginate beads were also prepared by adding magnetite in the formulation to allow fast removal from the aqueous solution with a magnet. Calcium alginate beads were added to commercial grape juice spiked with 20μg/kg OTA and after 48h of incubation a significant reduction (>80%), of the total OTA content was achieved, while in the subsequent phases (72–120h) OTA was slowly released into the grape juice by alginate beads. Biosorption properties of alginate-yeast beads were tested in a prototype bioreactor consisting in a glass chromatography column packed with beads, where juice amended with OTA was slowly flowed downstream. The adoption of an interconnected scaled-up bioreactor as an efficient and safe tool to remove traces of OTA from liquid matrices is discussed. This publication was made possible by NPRP grants # NPRP 4-259-2-083 and # NPRP 8-392-4- 003 from the Qatar National Research Fund (a member of Qatar Foundation).