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•Commercial asparaginase Preventase® was used in acrylamide mitigation of pizza base.•Enzymatic treatment up to 3–6 U/100 g does not affect the dough handling.•Preventase® W, M and XR-BG hardly reduced acrylamide levels in fried pizza base.•Acrylamide content in wood oven baked pizza base was halved by Preventase® W.

The concept of aseptic processing originated to solve problems associated with conventional ‘in-container’ sterilization of foods such as low rate of heat penetration to the slowest heating point in the container, the long processing times required to deliver the required lethality, destruction of the nutritional and sensory characteristics of the food, low productivity, and high energy costs. Aseptic processing technique has been successfully applied to liquid foods and acid foods containing discrete particulates. However, the extension of aseptic processing to heterogeneous low-acid liquid foods containing discrete particulates has been difficult due to lack of data on critical factors such as interfacial heat transfer coefficient between the liquid and the particle as well as the residence time distribution (RDT) of particles in the holding tube of the aseptic system. Geometry of holding tube represents a primary parameter in determining the residence time distribution of particulate inside an aseptic processing system. Several configuration had been investigate in the past, including curved geometries in order to minimize spreading of RTD. In the following work an experimental bypass holding tube is optimized numerically and experimentally. Numerical optimization was performed by using the Optimal Shape Design, where the essential element respect to classical numerical simulations in fixed geometrical configurations, is to introduce a certain amount of geometrical degrees of freedom as a part of the unknowns, which means that the geometry is not completely defined, but part of it is allowed to move dynamically in order to minimize or maximize the objective function.

The photorefractivity of an indole derivative and of its polymer blends has been studied at room temperature. The indole derivative 3-[2-(4-nitrophenyl)ethenyl]-1-(2-ethylhexyl)-2-methylindole (NPEMI-E) is a typical low-molecular-weight glass-forming molecule having peculiar nonlinear optics characteristics. It is unconditionally soluble in the photoconductive poly-(N-vinyl-2,3-dimethylindole) so that all the possible blends can be studied for a weight percent (wt. %) content of NPEMI-E ranging from zero to 100. A very high and sharp maximum of the photorefractive optical gain Γ_2 ≈ 2000 cm^−1 was obtained for a NPEMI-E wt. % content of about 90. On the basis of recently published theoretical calculations, we have made the hypothesis that the rapid change of Γ_2 can also be ascribed to a correspondingly quick variation of the molecular electro-optic parameters of the dissolved chromophore for some well distinguished values of its concentration in the polymer matrix. Differential scanning calorimetry measurements were made and the results carefully analyzed with the aim of obtaining information on the intermolecular interactions. These last measurements also allowed rationalizing the unconditionally stable glass appearance of the obtained blends. Measurements of spectroscopic ellipsometry were also made on blends with different NPEMI-E content.

Chitosan−whey protein edible films with different protein concentrations were prepared in the absence or presence of microbial transglutaminase as cross-linking agent. The films prepared in the presence of the enzyme showed low solubility at a wide range of pH, a lower degree of swelling, and good biodegradability following protease treatments. The presence of transglutaminase induced also an enhancement in film mechanical resistance and a reduction in their deformability. Finally, the barrier efficiency toward oxygen and carbon dioxide was found to be markedly improved in the cross-linked films which showed also a lower permeability to water vapor. Some potential practical applications of transglutaminase-treated chitosan−whey protein films are suggested.