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3. Pagani, M.A., Bottega, G., Caramanico, R., Lucisano, M., Mariotti, M., Franzetti, L. (2007).The debranning of common wheat (Triticum aestivum L.) as innovative tool for improvingflour characteristics. Proceedings of the CIGR International Symposium on “Food and agriculturalProducts: Processing and Innovations”. Naples, 24-26 SeptemberDebranning removes the external layers of kernels by means of abrasive action. This pre-milling operation isnecessary in the case of covered cereals (such as rice, oats, barley) in order to remove hulls of no technologicalor nutritional interest. Debranning is less frequent in “naked” (hull-less) grain processing. In the present study,the effects of this operation on common wheat (Triticum aestivum L.) was examined and the possibility of improvingthe hygienic characteristics of the flour was considered. The removal of a part of bran before milling,can in fact reduce risks associated with mycotoxins, contaminants present in the outer regions of kernels.The study was carried out using a pilot-plant debranning machine, with innovative abrasive elements lined withsynthetic diamond powder. The variables taken into consideration were the particle size of the abrasive elements,the processing time, the number of debranning steps and the hydration conditions of the kernels. The debranningeffects were observed by Scanning Electron Microscopy and quantified by evaluation both of the debranninglevel and several chemical and physical indices of kernels. The characteristics of debranning waste were comparedwith the bran obtained by the conventional milling process. In particular, the starch amount was consideredas the “marker” of an excessive endosperm abrasion, negatively related to flour yield. The trials, performedon two types of common wheat (hard and soft), evidenced the importance of a preliminary hydration step to reducekernel breakage. The best results were obtained with 3% water and a hydration time of less than 10 minutes.Synthetic diamond powder with fine particle size (180-200 mesh) allowed for a quite uniform abrasive action,with no deep grooves in the endosperm region, especially if a final brushing step was performed. Debranninglevels lower than 8-10% guaranteed low starch losses in the waste products but, at the same time, noticeablyreduced the microbial count of the kernels.4. Pagani, M. A., De Noni, I., D’Egidio, M. G., Cecchini, C. (2002). Effectiveness of debranningprocess of durum wheat for improving semolina quality. Proceedings of Second InternationalWorkshop on “Durum Wheat and Pasta Quality: Recent Achievements and New Trends”.Rome, 19-20 November, 157-161.Research performed on laboratory scale demonstrated that wheat debranning can improve semolina yield alongwith some of its technological properties. The debranning level (DL) was judged a key-factor as interesting resultswere obtained only if DL did not exceeded 10-12%. An industrial debranning process was then performedon two lots of commercial durum wheat kernels, the first characterized by high vitreousity (VWK) while the latterpresented more than 40% of starchy kernels (SWK) or “yellow berries”. The debranning was carried out atthree DLs for each lot of durum wheat (5, 7.5 and 12% for VWK; 5, 8.5 and 9% for SWK). The milling of thedebranned kernels was performed at a pilot-scale plant with different tempering times (3 and 6 hours). A rapidhydration step (15 min max) before debranning was useful in preventing the formation of high quantities of brokenkernels. The actual semolina yield increased some percentage points in comparison with unprocessed wheat.Best results were obtained with 7-8% DL. At the same time, no important differences were related to the lengthof pre-milling tempering, suggesting that a short time (only 3 hours) is preferable to optimise process productivity.Semolina from debranned kernels resulted in reduced ash content, better colour indices along with an improvementin alveographic parameters, especially for SWK. An overall evaluation of the results suggests thatdebranning can represent an interesting pre-milling process, suitable also for wheat parcels characterized by highlevel of starchy kernels.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it215