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Commercial cocoa and hazelnut-based sweet spreads typically present a poor nutribiochemical level due to their ingredients and recipes, while nowadays, there is the need of developing sustainable food products addressing both an improved nutritional and environmental profile. The aim of this work was then to develop an innovative hazelnut/carob-based spread with potential high sustainability and nutritional profile, including the exploitation of grape-processing residues (grape skin flour and grapeseed oil) and carob pulp as cocoa surrogate. Rheological (rotational/oscillatory), oxidative, and thermal features of the spread were assessed and compared with two commercial nut-cocoa-based products. Tribology was used to mimic and evaluate the spreads’ behavior during oral consumption, and sensory profile (by quantitative descriptive analysis) was also assessed. All products exhibited a pseudoplastic behavior, with the elastic component prevailing over the viscous one. The innovative product showed the highest lubricity from both rheological and sensory analysis, thus well correlating to the obtained lowest viscosity and friction factor trends. Grapeseed oil provided a better nutritional profile, but the largest amount of unsaturated fatty acids promoted oxidation, despite the higher total phenolic content and antioxidant capacity coming from the use of carob and grape skin powders. The sensory perception investigation revealed a characteristic mouthfeel/flavor for the new spread identified having a more fluid consistency and a bitter/sour taste, together with a greater stickiness and a poorer smoothness due to a higher fiber content and solid fat absence.

The aim of this work was to create an innovative sprayable bakery mix for foam-style cake preparation. The main goal was to obtain a batter liquid enough to be easily and quickly dosed in a spray system but maintaining its structure during baking. A commercial liquid batter was selected, and its recipe modified to fit in a spray system. The commercial bakery mix was characterized in terms of physical-chemical, thermal, and rheological attributes. The product was then diluted with milk or whipping cream at a 3:1 (gproduct/gdiluent) ratio to modulate its viscosity to be sprayed in a nitrous oxide loaded siphon system. All the prepared samples were characterized in terms of physicochemical properties at different stages of cake production (before and after spraying, and after baking) to investigate the effect of dilution on rheology and spray-ability and on the texture of final cake. Before cooking, the dilution determined an increase of water content and activity and a remarkable difference in colour coordinates compared to the reference.

Thermochemical and fractionation processes are promising ways for energy valorization and recovery of biomass and waste. An example is given by the application of a lignocellulosic fractionation process to recover both antioxidant phenolic compounds and cellulose from wheat straw, where a first hydrolysis step is carried out as a novel and green auto-hydrolysis process instead of conventional mild acid hydrolysis. Regarding this, the development of kinetic and reactor models that can represent the autohydrolysis process is crucial to exploit the potential of the agricultural residues (e.g., wheat straw). Several mathematical models were investigated, but the more suitable models for optimization purposes seem to be those based on a non-isothermal kinetic model. However, these models have several shortcomings. For instance, in the autohydrolysis process for the recovery of cellulose and lignin from by-products, the heating and cooling phases are not taken into account. Hence, from the point of view of energy optimization, closely linked also to economical optimization, this aspect becomes extremely important. Therefore, the aim of this work was to briefly present and comment, similarly to review work, the severity factor model and the kinetic model already investigated in the scientific literature in order to enable their comparison with the newly developed method in the current work in terms of different key performance indicators (e.g., cellulose recovery or sugar release). Specifically, our model includes new equations that consider both heating and cooling phases during autohydrolysis of wheat straw, as well as the isothermal step. In this way, it could be possible to use the obtained kinetic parameters not only for a specific case but also for different situations involving a wide range of operating conditions.

Frozen food sees a continuous increase in consumption thanks to the capability to preserve the organoleptic properties and, at the same time, to increase the shelf-life of the food itself. Therefore, a proper design of the freezing process is crucial and is strictly related to an accurate evaluation of freezing time because this establishes the minimum residence time of the product in a continuous freezer. For this reason, several mathematical models have been proposed and investigated for predicting the freezing time, starting from empirical models (lower accuracy and computational time) up to computational fluid dynamics simulation (higher accuracy and computational time). An excellent compromise between accuracy and computational effort seems to be a model that combines empirical laws for property evaluation and heat diffusion equation solved in one dimension. This model can numerically be solved using the method of lines in which spatial derivatives are discretized by the finite difference method and the resulting system of ordinary differential equations is integrated using an appropriate solver. This work aimed to fill some gaps to develop a comprehensive and more accurate model for freezing time prediction. Indeed, the key idea is to validate a model that could be used to optimize the refrigeration process for energy-saving and be the base for a design of experiment in case of lack of experimental data. The newly developed model includes the evaluation of freezing time for finite food shapes because, in some cases, it is not possible to assume a characteristic direction for heat flux. The property of unfrozen and frozen food (e.g. density, thermal conductivity, apparent specific heat, etc.) are evaluated basing on the principal constituent of food (e.g. water, fiber, protein, etc.), while heat transfer coefficient is evaluated using empirical equations, depending on adimensional numbers. In this way, it is possible to be flexible and not strictly related to the evaluation of the properties of food for each different case. The proposed model was validated with different sets of experimental data related to beef and strawberry pulp freezing. For these cases, the R2 index is equal to 0.982 and 0.996 respectively, showing a good agreement between experimental and predicted data. Finally, a case study of spinach cubes freezing was provided to show the potentiality of the novel model.

In this work sunflower oil (SFO) oleogels were obtained using rice bran wax (RBW) at 4.5 and 5.5% wt/wt. Bamboo fibre 40 µm (BF40) at 0.5% was investigated as structuring agent. The effect of fibre addition and cooling temperature (0, 4 and 25°C) on gel properties was evaluated compared to control samples prepared without fibre and at same cooling conditions. Rheological (both in rotational and oscillatory mode), texture and differential scanning calorimetry tests were carried out to assess thermal and structural parameters of gels. Oleogelatinization modified the rheological behaviour of samples, shifting from a typical Newtonian oil trend to a pseudo plastic non-Newtonian behaviour in gels. The gels resulted sensitive to temperature changes since a lower cooling temperature led to a structure weakening.

Thanks to their nutritional, healthy and sensory attributes, walnuts are raw materials of great interest for the agri-food sector. Nevertheless, a prolonged shelf-life is a fundamental requirement for promoting their industrial use. Rapid onset of rancidity can be avoided by adding preservative compounds and/or by applying stabilization processes able to make the fat component less prone to oxidation. The aim of this study was to evaluate the effect exerted by the addition of natural antioxidants (from grape skin) and/or by the application of an encapsulation technique on walnut paste. With the purpose of using them in bakery products, the developed formulations were subjected to thermal stress and used as ingredients in biscuits preparation: the impact of each treatment on fat fraction stability and antioxidant capacity was therefore assessed. In detail, walnut paste was obtained by roasting and grinding of kernels. An aliquot was enriched with 5000 ppm (w/w) grape skin extract in powder form. Both formulations were then encapsulated through a freeze-drying method, using maltodextrin DE12 and tragacanth gum as well materials. The chemical and oxidative analyses were performed on samples just after preparation, on the ones exposed to thermal stress (for 15 min at 180 °C) and on biscuits (baked at 180 °C for 15 min) that included just prepared samples. The results showed that the just prepared walnut paste supplemented with grape skin extract exhibited a greater antioxidant capacity, that was, however, reduced by heat treatment. Encapsulation procedure decreased the antioxidant capacity with a less evident effect on compounds revealed by FRAP and ORAC tests. The nutritional profile of just baked biscuits (intended as antioxidant capacity, phenolic profile, and tocopherol content) was not statistically influenced by the different formulations. In terms of induction period, encapsulated samples (and related biscuits) displayed higher values: the encapsulation process seemed to exert a barrier effect against oxidative agents and to protect the antioxidant properties of the grape skin extract, increasing the stability of both pasta and biscuits. In conclusion, recipe inclusion of encapsulated samples in just baked biscuits did not exert any benefits, neither in terms of oxidative stability, nor in terms of antioxidant properties. However, maltodextrins and gums, used as wall materials in the encapsulated samples, could help preserve the whole matrix prolonging the shelf-life of baking products containing them.

Gluten-free (GF) biscuits were prepared by replacing part of a GF flour mix (GFM) with 0, 15, 30 and 45 g/100 g (total flour) with a novel resistant starch-rich ingredient obtained from annealed white sorghum starch (RSWS). The chemical composition, physical characteristics, in vitro starch digestion and sensory evaluation of biscuits were considered. The chemical composition of samples was influenced by the addition of the RSWS. The highest total dietary fibre and RS contents (p < 0.05) were measured in 45-RSWS biscuits. The starch hydrolysis index values decreased when the level of RSWS increased in the composite. With regard to quality parameters, the use of RSWS influenced the hardness of the biscuits, and the highest value obtained for 45-RSWS. Some of the selected sensory attributes, along with the overall acceptability score, were negatively influenced by the RSWS addition, even if all remained above the limit of acceptability. The use of RSWS in GF biscuit formulation can contribute towards the creation of food products likely having slowly digestible starch properties, and this can be achieved without drastically compromising on the quality and sensory attributes.

In this work, extra-virgin olive oil (EVO)- and sunflower oil (SFO)-based oleogels were structured using rice bran wax (RBW) at 10% by weight (w/w). Bamboo fiber milled with 40 (BF40), 90 (BF90) and 150 (BF150) µm of average size was added as a structuring agent. The effect of fiber addition and cooling temperature (0, 4, and 25 °C) on thermal and structural parameters of achieved gels was assessed by rheological (both in rotational and oscillatory mode), texture, and differential scanning calorimetry tests. Oleogelation modified the rheological behavior of EVO and SFO, thus shifting from a Newtonian trend typical of oils to a pseudoplastic non-Newtonian behavior in gels. Moreover, oleogels behaved as solid-like systems with G′ > G″, regardless of the applied condition. All samples exhibit a thermal-reversible behavior, even though the presence of hysteresis suggests a partial reduction in structural properties under stress. Decreasing in cooling temperature negatively contributed to network formation, despite being partially recovered by low-granulometry fiber addition. The latter dramatically improved either textural, rheological, or stability parameters of gels, as compared with only edible oil-based systems. Finally, wax/gel compatibility affected the crystallization enthalpy and final product stability (gel strength) due to different gelator–gelator and gelator–solvent interactions.

The thermal stability of four different commercial citrus peel extracts was tested and improved by an encapsulation process with β-cyclodextrins in a spray-dryer. All extracts after the encapsulation process maintained a good antioxidant capacity, with an apparent loss in total phenolic compounds of around 20–25%. In addition, all samples showed good antimicrobial activity (MIC 5–0.625 mg/mL) against Staphylococcus aureus, which was maintained after the encapsulation process (MIC 5–1.25 mg/mL). Based on the antioxidant and antimicrobial activity results, the best-encapsulated citrus extract was selected for incorporation into a polylactic acid/polyhydroxy butyrate (PLA/PHB) film. The latter was then produced on an industrial scale by cast extrusion and was found to be suitable for food contact as it showed overall migration values in different food simulants lower than the legislative limit of 10 mg of non-volatile substances per 1 dm2 of surface area. The UHPLC-HRMS analysis, performed to evaluate the migration of the active compounds, revealed about 13.41% release in food simulant A and 11.02% in food simulant B. Antimicrobial analysis conducted directly on the film showed a growth inhibition activity towards Escherichia coli and Staphylococcus aureus equal to 30 and 60%, respectively.

This study investigated the effect of the addition of three commercial dried sourdoughs containing different percentages of Saccharomyces cerevisiae (25-30%), on structural characteristics of wheat bread. Rheology, texture and physicochemical characteristics were assessed for both dough and final bread. Control samples were prepared using common dried bakery’s yeast (100% S. cerevisiae). The rheological parameters complex viscosity (?), linear viscoelastic region (LVR), storage and loss modulus (G’ and G’’) and angular tangent (tand) were evaluated on the doughs through rheological tests carried out both in rotational and oscillatory mode. Final breads were characterised for the texture profile (hardness, springiness, cohesiveness and resilience). Moisture content and pH were monitored during the process. The leavening agents (dried sourdoughs and bakery’s yeast) were characterized for the content of total lactic acid bacteria and total yeasts. Rheological analysis highlighted a pseudo-plastic behaviour for all the doughs with the elastic component prevalent on the viscous one (G’>G’’), without substantial differences among samples before proofing. After 3 h leavening, storage and loss moduli and complex viscosity were lower than control for all the sourdough samples. Microbial evaluation showed no vital lactic acid bacteria in the dried sourdough that, contrary to the other two, did not give acidification during leavening and produced a final bread with texture properties comparable to those of the control.

Walnuts are appreciated all around the world by consumers and food industries because of their different and positive properties including flavouring, texturizing and nutritional qualities. Walnut paste production and use are commonly associated to confectionery or traditional products but may find space in different innovative foods, as fat replacer and functional component. The aim of this work was to increase the nutritional value of walnut paste and, at the same time, limit its oxidative degradation by developing a freeze-drying process with addition of polysaccharide matrices including dietary fiber. The effects of different formulations and technological treatments on product stability were evaluated. Shelled walnuts were roasted at 165 °C for 15 minutes, grinded, and refined; the obtained walnut paste was mixed with betaglucan, inulin and pectin, singly or combined with tragacanth gum and DE12 maltodextrin. The different formulations were added to water, emulsified and dehydrated by freeze-drying. Lyophilized samples were finally stored at 60 °C for 15 days. Walnut paste, samples just after lyophilization, and lyophilized samples after storage were evaluated in terms of moisture, peroxide number, acidity and pH, conjugated dienes and trienes, total phenols and tocopherols. Further analyses (color, 410 and 420 nm absorption, and total phenols content after ethanol precipitation) were carried out on freeze dried samples before and after storage. The results showed that the freeze-drying process affected the nutritional profile of the walnuts, limiting the onset of oxidative phenomena. After storage the content of total phenols and tocopherols was significantly higher already in the freshly lyophilized walnut paste, compared to the untreated one. The addition of polysaccharide compounds aided to preserve total phenols. However, when betaglucan, inulin, or pectin were individually included, a significant depletion of tocopherols was observed. Maltodextrin and tragacanth gum played a fundamental role in maintaining high levels of both total phenols and tocopherols. Nevertheless, formulations including also dietary fiber were slightly more oxidized. Among them, the inclusion of betaglucan provided the overall best results.

Sourdough fermentation of bakery products is a well-established and widespread technique to confer an added value to the resulting food. In recent decades, gluten-free raw materials have gained more attention due to the diffusion of food disorders such as coeliac disease, but, at the same time, they present difficult manipulation and scarce technological properties because of the absence of gluten. For this reason, the present work was aimed at selecting starter cultures for sourdough application that are isolated from fermentation of sorghum flour. Three isolates of Lactobacillus fermentum, Weissella cibaria, and Weissella confusa were selected for the following properties: exopolysaccharide synthesis, acidification, CO2 production, and amylase activity. The investigated phenotypic characteristics were confirmed by genomic analyses, which also highlighted other potentially beneficial features for use in bakery products employment. These strains, together with bakery yeast, were used for bread preparation using sorghum and wheat flour and after 24 h of fermentation the resulting dough was analyzed to assess the improvement of its characteristics. The presence of lactic acid bacteria (LAB) had a great impact on the final dough, and the best preparation, from a rheological point of view, resulted in one made of sorghum and wheat flour with added LAB and bakery yeast, whose resulting characteristics were similar to all wheat flour doughs. The results of this study suggest a potential application of the selected starters in sorghum composite bread and should be validated with data from large-scale pilot tests conducted in industrial bakeries.

Grape pomace is one of the major waste products generated by the wine-making process and it contains seeds and skins still rich in bioactive compounds. Skins can be separated from the seeds and valorised for the recovery of antioxidant extracts with different potential applications. The aim of this study was to evaluate the influence of the addition of an extract obtained from waste grape skins and encapsulated in maltodextrins on the antioxidant properties and sensory acceptability of whole wheat cocoa biscuits. Different levels of enrichment (1.2, 2.3, and 3.5% on dough weight) were tested, and the obtained doughs and biscuits were analysed for total phenols content and antioxidant capacity (based on different radical assays). Extract addition increased the phenolic content (up to 134% increase) and antioxidant capacity (up to 244%) of both doughs and biscuits. Extract containing biscuits were also characterised by a different colour. However, oxidation stability, evaluated at accelerated temperature and oxygen conditions, was not improved by the extract incorporation. Cooking led to an average (not always significant) 16% decrease in phenolic content for both enriched and reference recipes. The enrichment level significantly influenced the sensory acceptability, with identification of two clusters of consumers, with one cluster preferring the biscuits with the highest enrichment level and one cluster preferring the biscuits with the lowest level. The results showed that whole wheat cacao biscuits represent an appropriate food matrix to develop pleasant novel products enriched in phenolic compounds from waste grape skins and likeable for regular biscuits consumers.