Tackling food allergens-The role of food processing on proteins' allergenicity.

This chapter examines how innovative and emerging food processing technologies, such as those that use heat, electricity, electromagnetic waves, and pressure, can modify protein denaturation, aggregation, and intermolecular interactions pathways, which can result in varying immunoreactive responses. It emphasizes the need to understand how these processing methods affect the protein epitopes recognized by antibodies and their respective priming pathways, especially during the sensitization stage that precedes an allergic response. Although traditional processing methods have been investigated, the impact of novel technologies on food protein allergenicity remains largely unknown. The chapter specifically focuses on milk proteins, which have clinical significance and are associated with cow's milk allergy, one of the most common food allergies in young children. Additionally, it examines potential scientific advancements that novel processing methods may bring to this field.

Assessing the In Vitro Digestion of Lactoferrin-Curcumin Nanoparticles Using the Realistic Gastric Model.

Nanosized delivery systems have been the subject of research and discussion in the scientific community due to their unique properties and functionality. However, studies reporting the behaviour of nanodelivery systems under dynamic in vitro digestion conditions are still very scarce. To address this gap, this study aims to assess the dynamic in vitro gastric digestion of lactoferrin/curcumin nanoparticles in the realistic gastric model (RGM). For this purpose, the INFOGEST standard semi-dynamic digestion protocol was used. The nanosystems were characterized in terms of hydrodynamic size, size distribution, polydispersity index (PdI), and zeta potential using dynamic light scattering (DLS), before and during the digestion process. Confocal laser scanning microscopy (CLSM) was also used to examine particle aggregation. In addition, the release of curcumin was evaluated spectroscopically and the intrinsic fluorescence of lactoferrin was measured throughout the digestion process. The protein hydrolysis was also determined by UV-VIS-SWNIR spectroscopy to estimate, in real-time, the presence of free NH2 groups during gastric digestion. It was possible to observe that lactoferrin/curcumin nanoparticles were destabilized during the dynamic digestion process. It was also possible to conclude that low sample volumes can pose a major challenge in the application of dynamic in vitro digestion models.

Valorization of Amaranth (Amaranthus cruentus) Grain Extracts for the Development of Alginate-Based Active Films.

This research work investigates the development of alginate-based films incorporating phenolic compounds extracted from Amaranthus cruentus grain using different solvents. Alginate, glycerol, and amaranth grain phenolic compounds at various concentrations were used to produce the films. An experimental Central Composite Rotatable Design (CCRD) was used to evaluate the effect of these variables on different film's properties, i.e., water vapor permeability, hydrophobicity, moisture content, solubility, thermal, mechanical, and optical properties. This study demonstrated that high phenolic compound content and antioxidant capacity were obtained from amaranth grain using ethanol as the extraction solvent. Alginate films incorporating amaranth phenolic compounds were successfully manufactured, and this study can be used to tailor the formulation of alginate films containing amaranth phenolic compounds, depending on their final food application. For example, less flexible but more resistant and water-soluble films can be produced by increasing the alginate concentration, which was confirmed by a Principal Component Analysis (PCA) and Partial Least Squares (PLS) analysis. This study showed that active alginate films with amaranth phenolic compounds can be tailored to be used as food packaging material with potential antioxidant activity.

Emerging challenges in assessing bio-based nanosystems' behaviour under in vitro digestion focused on food applications - A critical view and future perspectives.

The current consumers' demand for high quality food products together with the growing awareness regarding the link between health and nutrition has led to the development of novel food products with added functionality. Such functionality can be modulated by adding bio-based nanosystems that can improve the bioaccessibility of bioactive compounds and facilitate nutrient absorption. However, these functional properties can be significantly affected by the adverse conditions (e.g., low pH, presence of enzymes, salts) of the gastrointestinal tract. As such, understanding the behaviour of such delivery systems under digestion conditions is of utmost importance and several analytical tools and in vitro digestion models have been used for this purpose. This review summarizes the latest updates on nanosystems' performance under in vitro digestion and provides critical insights related to important and complementary analytical tools (e.g., rheology, Raman spectroscopy, x-ray scattering) used to assess their performance throughout digestion. Furthermore, the most prominent and frequent challenges associated with such in vitro analyses are also described, together with the current trends regarding the development of in vitro digestion models and some considerations that should be undertaken for their validation. Efforts must be made towards developing reliable and standard in vitro digestion models that use sophisticated analytical techniques to further expand the knowledge regarding nanosystems' behaviour under in vitro digestion conditions.

Influence of the addition of different ingredients on the bioaccessibility of glucose released from rice during dynamic in vitro gastrointestinal digestion.

Rice represents a primary source of carbohydrates in human nutrition. Upon its consumption, the released sugars are mostly absorbed, categorising rice as a high glycemic index food. Addition of ingredients is common practice when cooking rice, which may affect rice digestibility and influence nutrients absorption in the gastrointestinal (GI) tract, enabling a controlled glucose release. In this sense, rice formulations were submitted to a dynamic in vitro GI model, constituted by reactors that simulates peristalsis coupled to filtration membranes, to evaluate carbohydrates hydrolysis and bioaccessibility. Addition of quinoa and wholegrains reduced carbohydrates hydrolysis (i.e. 38.5 ± 5.08% and 57.98 ± 1.91%, respectively) and glucose bioaccessibility (i.e. 25.92 ± 5.70% and 42.56 ± 1.39%, respectively) when compared with brown rice (i.e. 63.86 ± 2.96% hydrolysed and 44.33 ± 1.88% absorbed). Addition of vegetables significantly decreased sample chewiness and resulted in superior hydrolysis (71.75 ± 7.44%) and glucose absorption (51.61 ± 6.25%).

Rice in vitro digestion: application of INFOGEST harmonized protocol for glycemic index determination and starch morphological study.

Starch is the main sugar source present in staple foods. Understanding starch hydrolysis during digestion and the resulting glucose release can be important to strategically modulate starch digestion and glucose absorption. In vitro digestion methodologies are fundamental to evaluate starch hydrolysis length and rate, but the lack of uniformity between protocols prevent the comparison of results. In this context, three different Carolino rice varieties (i.e., Carolino white-Cw, Carolino brown-Cb and Carolino Ariete brown-CAb) were submitted to the INFOGEST harmonized in vitro digestion protocol for the evaluation of starch hydrolysis and subsequent glycemic index (GI) determination, and starch granules morphological study. Samples of Carolino rice presented total starch percentages between 64.52 (for Cb) to 71.52% (for Cw) with low amylose content (16.19-19.95%, varying in the following order Cb < Cab ≈ Cw). During digestion, between 39.43 (for CAb) to 44.48% (for Cb) of starch was hydrolyzed, classifying samples as medium GI foods (61.73-69.17). Starch hydrolysis was accompanied by a decrease of starch granules dimensions. For all samples, area decrease was higher than 59%, perimeter decrease was higher than 37%, feret diameter decrease was higher than 39% and minimum feret diameter decrease was higher than 32%. This work provides new insights to describe, both qualitatively and quantitatively, the fate of rice during digestion, and allowed establishing a comparative basis for the development of rice-based recipes with a lower GI.

Micro- and nano bio-based delivery systems for food applications: In vitro behavior.

Micro- and nanoencapsulation is an emerging technology in the food field that potentially allows the improvement of food quality and human health. Bio-based delivery systems of bioactive compounds have a wide variety of morphologies that influence their stability and functional performance. The incorporation of bioactive compounds in food products using micro- and nano-delivery systems may offer extra health benefits, beyond basic nutrition, once their encapsulation may provide protection against undesired environmental conditions (e.g., heat, light and oxygen) along the food chain (including processing and storage), thus improving their bioavailability, while enabling their controlled release and target delivery. This review provides an overview of the bio-based materials currently used for encapsulation of bioactive compounds intended for food applications, as well as the main production techniques employed in the development of micro- and nanosystems. The behavior of such systems and of bioactive compounds entrapped into, throughout in vitro gastrointestinal systems, is also tracked in a critical manner. Comparisons between various in vitro digestion systems (including the main advantages and disadvantages) currently in use, as well as correlations between the behavior of micro- and nanosystems studied through in vitro and in vivo systems were highlighted and discussed here for the first time. Finally, examples of bioactive micro- and nanosystems added to food simulants or to real food matrices are provided, together with a revision of the main challenges for their safe commercialization, the regulatory issues involved and the main legislation aspects.