The impacts of total hot air drying (THD) and the swell-drying process (SD), which is hot air drying coupled with an instant controlled pressure drop DIC process, on the drying kinetics and adsorption isotherm behavior, were determined in the case of Moroccan peppers. Drying kinetics were studied through a model that takes into account the starting accessibility and the internal diffusion model with Fick's law. Adsorption experimental data were obtained by using the gravimetric method at 25, 40, and 50 C. Data were fitted to the GAB, Halsey, and Oswin models. Studied responses were: effective diffusivity (D eff ), starting accessibility (dW s ), monolayer moisture content (X m ), specific surface area (r), internal porosity (e), and microstructure. Mean relative percentage deviation (E) and root mean square (RMS) were used to evaluate the fitting of models. Results showed that: pepper adsorption isotherms followed the type II isotherm curve;the equilibrium moisture content (X eq ) depended on the temperature and the drying method; the GAB and Halsey models fitted well the experimental data; at selected conditions of the DIC treatment (0.35 MPa and 5 s), the monolayer moisture content (X m ), the specific surface area (r), and the internal porosity values were higher than those of THD samples; the DIC process intensified the drying operation, by increasing the effective diffusivity and the starting accessibility. Although the DIC process improves the drying kinetics, this behavior could be ignored related to a higher a w . This study shows that, thanks to the new expanded structure obtained by the DIC process (higher porosity), the adsorption capacities of products are improved (a w is reduced). Thus, the SD process improves both the drying operation and the stability of dried pepper products.

Some special thermal and mechanical treatments may completely modify the composition, and the structure of organic material changes its interaction with water. In the case of the instant controlled pressure drop (DIC) technique, the main modification, which is structure expansion and high porosity, allows the product to generally reduce moisture activity. In the special case of cork granules, the impact of DIC in terms of porosity is completely absent and expansion is linked to a tear effect obtained from only the large size granules. In order to characterize this type of treatment, we considered natural and DIC-treated cork granules and determined moisture adsorption isotherms at three different temperatures (25, 40, and 60 C) and different water activity levels ranging from 0.05 to 0.9 using the static gravimetric method. We used three samples of the same cork variety with 0.5-1 mm, 2-4 mm, and 4-6 mm as granule diameter. The adsorption isotherms of both natural untreated and DIC-treated cork whatever granules display a sigmoid form type II isotherm, with equilibrium moisture contents at constant water activity decreasing when temperature increases. The impact of DIC treatment depends of cork shape; the larger the shape, the lower the water activity for the same water content. Such a result is linked to the modification of structure. Thus, for the smallest shape, DIC implying only low thermal effect without any structure modification allows cork to lightly increase its water activity compared to the untreated samples. With higher shape cork granules, as DIC treatment induces a tear effect and some expansion, activity of water is lower for the same water content. For describing the experimental data of adsorption isotherms, we used GAB, BET, and Henderson models. We found the GAB to be the most suitable model with predicted values higher than those obtained using the BET model. We note that monolayer moisture content values increase in the case of big shape cork granules after having been treated by DIC.

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In this study, the addition of Sweet lupin seeds flour (SLSF) in different levels (5, 10 and 15%) to wheat flour (WF) was evaluated. Dough mixing properties, bread physical characteristics and sensory properties were investigated. Increasing SLSF level in the SLSF-WF composites led to an increased water absorption, dough development time, C4 and setback torque, while it decreased flour moisture, dough stability, C2, C3 and C5 when analyzed by Mixolab. The SLSF-WF composites produced darker bread, lower specific volume, and harder crumb. Higher antioxidant activities, higher protein and minerals contents were scored by pan bread containing SLSF. Bread samples enhanced with SLSF (5, 10 and 15%) were accepted by panelists for their aroma, crust and crumb color, texture, taste and overall-acceptability. The best acceptability of bread was obtained by addition of 5% SLSF even compared to control wheat bread.

The effect of addition moringa leaves extract (MLE) on physical, chemical and sensory properties of luncheon was investigated. Luncheon samples were supplemented with 0.5, 1.0 and 1.5% of MLE. Results showed that supplementation of luncheon with MLE increased its content of protein, fiber and antioxidants. Protein content ranged from 8.49% in control to 10.90% in luncheon sample with 1.5% MLE. Total phenolic content of MLE was ranged from 65 to 67 mg/100g (as Gallic acid equivalent) while, the scavenging effects of 100 µl of MLE were ranged from 79.51 to 88.57%. The thiobarbituric acid number (TBA) values increased for all the investigated luncheon samples gradually during storage period. The highest value for TBA was noticed in L1 (control sample 1) (0.5239) after four weeks of cold storage while, the lowest value was observed with luncheon meat containing 0.01% butylated hydroxytoluene (BHT) (L2) (0.1251) at zero storage. The total polyphenol contents and antioxidants activity increased in luncheon meat after the addition of moringa leaves extract. All the luncheon meat samples containing moringa leaves extract were generally acceptable.