Mondher Hachani
@ucar.rnu.tn
Higher Institute of Sciences and Technology of Environment
University of Carthage
RESEARCH, TEACHING, or OTHER INTERESTS
Geology, Ceramics and Composites, Waste Management and Disposal, Building and Construction
Scopus Publications
Scopus Publications
Sana Ben Amara, Atef Lakoud, Imen Mahmoudi, Imene Ben Tekaya, Assila Amri, Ahmed Snoussi, Mondher Hachani, Sami Fattouch, and Mnasser Hassouna
MDPI AG
The production of date paste from second-grade date fruits is a fast-growing industrial activity which promotes more sustainable food systems. The industrial date paste process is mainly dependent on the thermal treatments of hydration and drying that precede flesh crushing. These thermal treatments are commonly performed industrially using steam hydration instead of water soaking and convective hot air drying, which are known to be energy-intensive operations leading to high greenhouse gas emissions. The objective of this work was to optimize, on the one hand, the operations of hydration and drying of dates at an industrial scale using a response surface Box–Behnken experimental design in order to reduce the energy consumption and, on the other hand, to assess the biochemical and microstructural properties of date paste produced under optimized conditions. Optimization was performed based on the measurements of sensory attributes, instrumental texture firmness, moisture content, water activity (aw), and color parameters (L*, a*, b*), as well as on the energy savings related to the factors of hydration duration and temperature and time of drying. The optimal conditions to ensure the highest quality of the final product and the lowest energy consumption were 9.6 min of hydration at 80 °C and 3 h of drying at 52.28 °C. The biochemical analysis of the date paste produced under the optimized process showed that it is rich in dietary fibers (9.80 ± 2.10%) and total phenols (261 ± 6.2 mg gallic acid equivalent/100 g of extract). Furthermore, the studied sample exhibited a higher antioxidant potential than the raw date material as a result of the heat-inhibitory effect of oxidases. The obtained results suggest that date paste presents a good source of natural bioactive molecules and could potentially be considered as a functional food ingredient. SEM analysis showed that the microstructural properties of date paste produced under optimal conditions may promote its quality preservation during storage.
B. Moussi, W. Hajjaji, M. Hachani, N. Hatira, J.A. Labrincha, J. Yans, and F. Jamoussi
Elsevier BV
M. Medhioub, W. Hajjaji, M. Hachani, A. Lopez-Galindo, F. Rocha, J. A. Labrincha, and F. Jamoussi
Mineralogical Society
AbstractThis study aims to find alternatives to some overexploited deposits in the north of Tunisia. The clays of the Sidi Khalif formation, of Uppermost Jurassic to Lower Cretaceous age, seem suitable to support this strategy, due to their abundance. In terms of mineralogy, they can be divided into two distinct groups, related to their palaeogeographic and eustatic contexts. The clays of the Sidi Khalif formation from Jebel Houareb (JH) and Jebel Meloussi (JM) are richer in clay minerals, while those of Jebel Rhouis (JR) and Jebel Boudinar (JB) zones are dolomite-rich. The compositional differences between the two groups influenced their technological behaviour in production of ceramic tiles. Upon firing, forsterite and gehlenite crystallized in the carbonate-rich JR and JB clays, whereas mullite formed in the JH and JM clays. Concerning their ceramic properties, the tiles made from JR or JB clays showed low bending strength and high water absorption. For JH and JM, the tiles had slightly greater mechanical resistance, but exhibited considerable linear shrinkage. These defects were partially corrected by introducing new formulations based on the same clays and by altering the firing cycles (HM1, HM2, RB1 and RB2). With these modifications, “Porcelanico” and “Monoporosa” technologically conforming tiles were obtained from HM2 and RB2 formulations, respectively.
M. Hachani, W. Hajjaji, B. Moussi, M. Medhioub, F. Rocha, J. A. Labrincha, and F. Jamoussi
Mineralogical Society
AbstractThe aim of this research was to assess the potential application of the Late Cretaceous levels as raw material for the production of ceramic tiles. Mineralogical, chemical and grain size distribution studies were carried out on four clays sampled at different sites in the Tunisian Central Atlas. Clays are mainly composed of phyllosilicates, usually illite and kaolinite. Quartz, feldspars and dolomite were also detected.Tiles were prepared by pressing clay bodies at 250 bar and then firing at different temperatures following industrial conditions as closely as possible. Thermal analysis showed the influence of mineralogical composition and grain size distribution on the material behaviour during firing. The physical properties of fired tiles were obtained from specific tests in accordance with international standards (ISO), i.e. the firing shrinkage, water absorption, apparent density and flexural strength. The development of physical properties indicates an optimal firing range between 1050–1150°C. Results demonstrate the potential of Late Cretaceous materials as raw materials for the production of ceramic tiles.
W. Hajjaji, B. Moussi, M. Hachani, M. Medhioub, A. Lopez-Galindo, F. Rocha, J.A. Labrincha, and F. Jamoussi
Elsevier BV
W. Hajjaji, M. Hachani, B. Moussi, K. Jeridi, M. Medhioub, A. López-Galindo, F. Rocha, J.A. Labrincha, and F. Jamoussi
Elsevier BV
K. Jeridi, M. Hachani, W. Hajjaji, B. Moussi, M. Medhioub, A. López-Galindo, F. Kooli, F. Zargouni, J. Labrincha, and F. Jamoussi
Mineralogical Society
AbstractLower Cretaceous (AJO and AJR) and Oligocene clays (AS) from northern Tunisia were analysed to evaluate their possible use in the production of earthenware tiles by dry processing and fast double-firing. The Cretaceous clays are carbonate-rich (AJO = 20%, AJR = 12%) while the Oligocene ones are carbonate-free. This led to noticeable differences in firing behaviour (shrinkage, sintering rate and loss on ignition) and consequently in functional properties (water absorption, mechanical strength, porosity). The AJO firing shrinkage is very small, which makes this clay suitable for rapid firing. The clays are illite-kaolinite-rich but the AS sample is mostly smectitic (44%) and so is used (10 wt.% maximum) only to adjust the consistency of the powder during pressing. The average agglomerate size ranges from 100 to 350 μm and the distribution is suitable for easy pressing of powders without any special need for further adjustments. Characterization of fired products confirms the high potential of these clays since all properties fall within the ceramic International Standards (ISO). For both technical and economic reasons dry processing is recommended for production of earthenware tiles, in particular for countries in sunnier climates, where solar energy can be exploited for clay drying.