A definitive screening design was used in order to evaluate the effects of starch, glycerol and montmorillonite (MMT) concentrations, as well as the drying temperature, drying tray type and starch species, on packaging film’s functional properties. Optimization showed that in order to obtain films with the minimum possible thickness, the maximum elongation at break, the maximum tensile strength, as well as reduced water vapor permeability and low opacity, a combination of factors should be used as follows: 5.5% wt starch concentration, 30% wt glycerol concentration on a dry starch basis, 10.5% wt MMT concentration on a dry starch basis, 45 °C drying temperature, chickpea as the starch species and plexiglass as the drying tray type. Based on these results, starch films were prepared, and fresh minced meat was stored in them for 3 days. It was shown that the incorporation of MMT at 10.5% wt on a dry starch basis in the packaging films led to a decreased mesophilic and psychrotrophic bacteria growth factor compared to commercial packaging. When assessed for their biodegradability, the starch films disintegrated after 10 days of thermophilic incubation under simulated composting conditions. Finally, to prove their handling capability during industrial production, the starch films were rewound in a paper cylinder using an industrial-scale rewinding machine.

The spray-dried potato starch was produced by gelatinizing native potato starch at two concentrations of 3% and 5% at 75 °C for 30 min, followed by drying in a pilot-scale spray dryer. X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and optical microscopy were applied to characterize native potato starch and spray-dried (SD) potato starch powders. The physical properties of the starches, including moisture content, color, bulk density, tapped density, particle size parameters, water holding capacity, and hygroscopicity, were investigated. XRD, DSC, and FTIR revealed the formation of a semi-crystalline to amorphous structure in the spray-dried starch powders. Microscopic examination showed that the starch granules of native potato starch were spherical and regular in shape, while spray-dried (SD) starch powders displayed wrinkled granules. The moisture content of the spray-dried powders was significantly lower than that of the native starch, while the native starch had higher particle size values [D(4.3)] compared to the spray-dried powders. Higher water holding capacity values were also recorded in the spray-dried starches compared to the native starch. Regarding the color parameters, statistical analysis revealed similar values for lightness (L*) and yellowness (YI) indices, while significant differences were found in hue angle (H°), a*, and b* values. A principal component analysis (PCA) was carried out to investigate the relationships among the physical properties of the native potato starch and spray-dried starch powders. The findings of the present study highlight the potential application of physically modifying starch through the spray-drying process.

Synthetic polymers are the main food packaging material, although they are nonbiodegradable and their recycling process is expensive. A biodegradable, eco-friendly material, with high availability and low cost, such as starch, is a promising solution for the production of films for food packaging. To enhance starch film mechanical and barrier properties, nanoclays have been incorporated within the film matrix. Crosslinking is a well-established method to modify starch properties, but it has not been investigated in combination with nanoclay addition. In the present study, films were developed with starch that was crosslinked through the addition of 5, 15, and 40% wt. sodium trimetaphosphate (STMP) based on dry starch weight. To investigate the interaction between crosslinking and nanoclay addition, montmorillonite (MMT) was added at a 10.5% wt. concentration based on dry starch weight. Experimental data revealed a synergistic effect between STMP crosslinking and MMT addition regarding film thickness, elongation at break, color properties, and opacity. Regarding barrier properties, MMT addition negated the effect of STMP crosslinking, while, in the case of moisture content, it did not alter the effect of STMP crosslinking. Finally, in the case of tensile strength, a synergistic effect followed by a negative interaction was observed. In conclusion, the addition of MMT can potentially enhance, alongside crosslinking, some properties of the films, while other properties are not affected any more than just by crosslinking.

The objective of the present work was the formulation, optimization and quality evaluation of gluten free biscuits at different water levels, based on a rice and carob flour mixture enriched with dried apple pomace, prepared with and without microwave blanching (MB). MB contributed to partial conversion of insoluble dietary fiber to soluble. Increasing of dried apple pomace proportion in the mixture resulted in higher sensory aroma and hardness and higher brightness (L*) and red hue (a*). On the other hand, the increase of water level caused a rapid increase in biscuits moisture and a drastic reduction of sensory hardness and crispness, and of mechanical fracture force and spread factor. Sensory hardness and crispness were positively correlated with mechanical fracture force and spread factor (W/T). Three biscuit formulations with % levels (A:C:W) of apple pomace (A), carob flour (C) and water (W) were found to score highest (34:16:50, 32.5:32.5:35, 49:16:35).

Hemp protein (Cannabis sativa L.) was incorporated into wheat flour at concentrations of 5%, 10%, and 15% and its effects on the rheological properties of the dough and the quality characteristics of the resulted breads were investigated. Rheological analysis revealed that hemp protein-enriched doughs exhibited significantly higher Young’s modulus of elasticity and elongational viscosity values compared to the wheat flour dough, indicating that the incorporation of hemp protein affected the firmness of the doughs. Farinograph analysis showed that replacing wheat flour with hemp protein increased water absorption, dough development time, and stability, while extensiograph analysis showed increased dough resistance and decreased extensibility and energy with hemp protein addition. Statistical analysis revealed that hemp protein significantly affected the moisture content, specific volume and crumb color of breads. Bread fortified with hemp protein had a darker color compared to the control bread. The addition of hemp protein affected the texture of the breads. It is recommended that hemp protein could be utilized as an alternative protein source, potentially enhancing dough characteristics, texture, quality, and the nutritional value of protein-rich breads, biscuits, snacks, and other bakery products.

Fresh mussels (Mytilus galloprovincialis) were heat-treated for various time intervals, using moist-heat and dry-heat processes such as boiling, steaming, baking, and microwaving. The effect of heat treatment methods on cooking loss and shucking (shell opening) of mussels was investigated. All heat treatment methods succeeded 100% shell opening. Results indicated that cooking loss and shell opening of the heat-treated mussels significantly increased with increasing process time. The cooking loss was for the majority of the heat-treated mussels higher than 20% while greater cooking loss values were recorded for the steam-treated mussels. Microwave heating scored better results in shell opening of the mussels compared to the other methods. Multiple response optimization of process parameters revealed that the microwave treatment was found to be the optimal for improving the quality (cooking loss) and the efficiency of shell opening of mussels. The color of the heat-treated mussel meat was more or less orange. Practical applications Nowadays, the food industry faces the challenge to explore new methodologies in order to improve the quality characteristics of their products and, thereby, gain the consumers acceptability. During mussel heat processing, cooking loss is a very important factor strongly related to the heat treatment methods and affects the quality and yield of the final product. Although heating may lead to significant cooking losses, it is required in order to facilitate the shucking of mussels. To address this matter, in this study, the effect of different heat treatment methods on cooking loss and shell opening of mussels are investigated. The results suggest that the microwave heat treatment method can potentially be implemented in industrial mussel processing, guarantying better quality end products than the other methods do.