How D-amino acids embedded in the protein sequence modify its digestibility: Behaviour of digestive enzymes tested on a model peptide used as target.

D-amino acids can affect the action of digestive enzymes, hence the protein digestion. In this work the behaviour of the main stomach and gut digestive enzymes (pepsin, trypsin, and chymotrypsin) in the presence of D-amino acids in the protein chain was monitored over time using a model peptide, Ac-LDAQSAPLRVYVE-NH (belonging to β-lactoglobulin, position 48-60), where L-amino acids were systematically substituted by D-amino acids. The results showed several changes in the behaviour of digestive enzymes, not only when the D-amino acids are inserted at the specific cleavage sites (after Val-57), but in some cases also when in distant positions.

Formulation of new sourdough bread prototypes fortified with non-compliant chickpea and pea residues.

Purpose: Nowadays, the promotion of a circular economy is fundamental to reduce food losses and waste. In this context, the possibility of using food supply chains non-compliant residues emerges. Much interest has been directed toward legume residues, in general and, in particular, to the possibility of combining different plant-matrices to improve nutritional profile, providing high-quality products.

Exploitation of bones-rich poultry by-products to produce protein hydrolysates: optimization of hydrolysis parameters and chemical characterization.

A significant quantity of bone-rich poultry by-products must be disposed of by poultry processors. These products still contain a significant amount of nutritionally valuable animal proteins. In the present work, a hydrolysis protocol was optimized to recover the protein fraction of bone-rich poultry by-products while simultaneously minimizing the amount of water required for hydrolysis (thus reducing drying costs) and recycling the hydrolytic broth up to 3 times, to reduce the cost of the proteolytic enzyme.

Molecular Characterization of the Allergenic Arginine Kinase from the Edible Insect Hermetia illucens (Black Soldier Fly).

Scope: Arginine kinase (AK) is an important enzyme for energy metabolism of invertebrate cells by participating in the maintenance of constant levels of ATP. However, AK is also recognized as a major allergen in insects and crustaceans capable of cross-reactivity with sera of patients sensitized to orthologous proteins. In the perspective of introducing insects or their derivatives in the human diet in Western world, it is of primary importance to evaluate possible risks for allergic consumers.

Assessment of Protein Quality and Digestibility in Plant-Based Meat Analogues.

In this first work, commercial steak-like ( = 3) and cured meat ( = 3) analogues with different legume and cereal formulations were studied and compared to their animal-based ( = 3) counterparts. Plant-based products showed lower protein content than meat controls but a good amino acidic profile even though the sum of essential amino acids of plant-cured meats does not fulfill the requirements set by the Food and Agriculture Organization for children. A comparable release of soluble proteins and peptides in the digestates after in vitro digestion was observed in meat analogues as meat products, whereas the digestibility of proteins was lower in plant-based steaks and higher in plant-based cured meats than their counterparts.

Molecular characterization and allergenicity assessment of different samples of Mung Bean.

Legumes represent a promising nutritional alternative source of proteins to meat and dairy products. Additionally, Novel Foods (Regulation EU 2015/2283) can help meet the rising protein demand. However, despite their benefits, emerging allergenicity risks must be considered.

Comparison of protein quality and digestibility between plant-based and meat-based burgers.

Nowadays, consumers are increasingly inclined toward plant-based meat analogues for sake of food security, safety, and sustainability. This growing interest, not only from consumers but also from food companies, brought the offer on the market to be wide and vast. From our previous study it emerged that the market supply, especially the Italian one, is diversified both in terms of protein sources and nutrient content.

Protein Quality and Protein Digestibility of Vegetable Creams Reformulated with Microalgae Inclusion.

Microalgae are considered a valuable source of proteins that are used to enhance the nutritional value of foods. In this study, a standard vegetable cream recipe was reformulated through the addition of single-cell ingredients from (spirulina), , , or at two levels of addition (1.5% and 3.

Evaluation of in vitro whey protein digestibility in a protein-catechins model system mimicking milk chocolate: Interaction with flavonoids does not hinder protein bioaccessibility.

Flavonoids are largely present in plant food such as cocoa and derived products. These compounds can interact with proteins inherently contained in the food matrix and/or the proteolytic enzymes involved in gastrointestinal digestion. The flavonoid/protein interaction might hamper protein bioaccessibility and digestibility, affecting the nutritional quality.

Label-Free Quantification by Liquid Chromatography-Tandem Mass Spectrometry of the Kunitz Inhibitor of Trypsin KTI3 in Soy Products.

The greater awareness of consumers regarding the sustainability of food chains has shifted part of the consumption from animal protein sources to vegetable sources. Among these, of relevance both for human food use and for animal feed, is soy. However, its high protein content is unfortunately accompanied by the presence of antinutritional factors, including Kunitz's trypsin inhibitor (KTI).

Cleaning the Label of Cured Meat; Effect of the Replacement of Nitrates/Nitrites on Nutrients Bioaccessibility, Peptides Formation, and Cellular Toxicity of In Vitro Digested Salami.

Curing salts composed of mixtures of nitrates and nitrites are preservatives widely used in processed meats. Despite many desirable technological effects, their use in meat products has been linked to methemoglobinemia and the formation of nitrosamines. Therefore, an increasing "anti-nitrite feeling" has grown among meat consumers, who search for clean label products.

Effectiveness of enzymatic hydrolysis for reducing the allergenic potential of legume by-products.

The interest in agri-food residues and their valorization has grown considerably, and many of them are today considered to be valuable, under-exploited sources of different compounds and notably proteins. Despite the beneficial properties of legumes by-products, there are also some emerging risks to consider, including their potential allergenicity. In this work the immunoreactivity of chickpea, pea, and white bean by-products was assessed, and whether the production of enzymatic hydrolysates can be an effective strategy to reduce this allergenic potential.

Peptide profile of Parmigiano Reggiano cheese after simulated gastrointestinal digestion: From quality drivers to functional compounds.

Time of ripening has a strong impact on shaping the valuable and recognizable characteristics of long-ripened types of cheese such as Parmigiano Reggiano (PR) due to the interrelationship between microbiota and proteolysis that occurs during ripening. The derived peptide profile is linked to cheese quality and represents the canvas for enzymes upon digestion, which could be responsible for the release of potentially bioactive peptides (BPs). In this study, we aimed at investigating the presence of BP in 72 PR cheese samples of different ripening times, from curd to 24 months of ripening, produced in six different dairies, and following their fate after simulated gastrointestinal digestion.

Assessing food authenticity through protein and metabolic markers.

This chapter aims to address an issue of ancient origins, but more and more topical in a globalized world in which consumers and stakeholders are increasingly aware: the authenticity of food. Foods are systems that can also be very complex, and verifying the correspondence between what is declared and the actual characteristics of the product is often a challenging issue. The complexity of the question we want to answer (is the food authentic?) means that the answer is equally articulated and makes use of many different analytical techniques.

Looking for peptides from rice starch processing by-product: Bioreactor production, anti-tyrosinase and anti-inflammatory activity, and putative taste assessment.

One of the major challenges for the modern society, is the development of a sustainable economy also aiming at the valorization of agro-industrial by-products in conjunction with at a significant reduction of generated residues from farm to retail. In this context, the present study demonstrates a biotechnological approach to yield bioactive peptides from a protein fraction obtained as a by-product of the rice starch production. Enzymatic hydrolysis, with the commercial proteases Alcalase and Protamex, were optimized in bioreactor up to 2 L of volume.

Nutritional Quality of Meat Analogues: Results From the Food Labelling of Italian Products (FLIP) Project.

Nowadays, the interest in meat substitutes is increasing, and consumers perceive their nutritional quality better than that of the animal products they intend to resemble. Therefore, this work aimed to investigate the overall nutritional quality of these new products. Regulated information [Regulation (EU) 1169/2011], the presence/absence of nutrition or health claim and organic declarations, the gluten-free indication, and the number of ingredients were collected from the food labels of 269 commercial meat analogues currently sold on the Italian market.

Structural and chemical changes induced by temperature and pH hinder the digestibility of whey proteins.

In the food and feed industry, protein extraction is commonly performed under acid or basic conditions, combined with heat, in order to increase the extraction yield. Under severe processing conditions, proteins may undergo molecular modifications. Here, the effects of heating (30, 60, 90 °C) at different pH values (2, 7, 9, 11, 13) were evaluated on commercial whey proteins, used as a simplified protein model.

Impact of a Shorter Brine Soaking Time on Nutrient Bioaccessibility and Peptide Formation in 30-Months-Ripened Parmigiano Reggiano Cheese.

Reducing the salt content in food is an important nutritional strategy for decreasing the risk of diet-related diseases. This strategy is particularly effective when applied to highly appreciated food having good nutritional characteristics, if it does not impact either upon sensory or nutritional properties of the final product. This work aimed at evaluating if the reduction of salt content by decreasing the brine soaking time modifies fatty acid and protein bioaccessibility and bioactive peptide formation in a 30-month-ripened Parmigiano Reggiano cheese (PRC).

simulated semi-dynamic gastrointestinal digestion: evaluation of the effects of processing on whey proteins digestibility and allergenicity.

The effect of thermal processing on digestibility of milk proteins should be better understood as this can greatly affect their immunoreactivity. The aim of this study was to evaluate the effects of thermal processing and lactosylation on digestibility and allergenicity, by comparing non heat-treated with industrially processed whey proteins. A semi-dynamic model was used to mimic the kinetics of digestion, and ELISA inhibition tests against human specific serum IgE were performed on the mass-spectrometry characterized products.

Extraction and Chemical Characterization of Functional Phenols and Proteins from Coffee () By-Products.

Not all the coffee produced goes to the roasting stage, because non-compliant green coffee beans are usually discarded by roasters and the silverskin of the coffee is usually removed and discarded. In the present work, non-compliant green coffee beans and coffee silverskins were fully characterized from a chemical point of view. In addition, enzyme-assisted extraction was applied to recover a fraction rich in proteins and polyphenols, tested for antimicrobial, antityrosinase, and antioxidant activities.

Targeting the Nutritional Value of Proteins From Legumes By-Products Through Mild Extraction Technologies.

Legumes have been known for centuries for their good nutritional properties. Unfortunately, during processing, from 5 to 25% of this production is wasted, generating by-products that can still be a rich source of useful compounds, such as proteins, which can still be used in food and feed formulations. The choice of the extraction technique is important to preserve the nutritional value of proteins since drastic conditions of pH and/or temperature could damage them.

Enzymatic Digestion of Calf Fleshing Meat By-Products: Antioxidant and Anti-Tyrosinase Activity of Protein Hydrolysates, and Identification of Fatty Acids.

The food waste reduction through an efficient recovery of its valuable building molecules has become an important topic with a positive effect on the economy and the environment. In this work, the revalorization of slaughterhouse calf fleshing meat through its enzymatic hydrolysis is proposed. The proteolytic activity of 11 enzymes was initially screened and the four most efficient enzymes (papain, trypsin, pancreatin, and bromelain) were selected.

Reduction in the Brining Time in Parmigiano Reggiano Cheese Production Minimally Affects Proteolysis, with No Effect on Sensory Properties.

Brine soaking is one of the most important steps in the production of Parmigiano Reggiano cheese, since it determines the amount of salt in the final product. Reduction in salt in Parmigiano Reggiano cheese might be important for improving its nutritional profile, but it could affect the manufacturing processes by altering proteolysis and consequently the product quality. In this study, for the first time, salt reduction was explored at the industrial level on real cheese samples manufactured in a local dairy.

State-of-the-Art Production Chains for Peas, Beans and Chickpeas-Valorization of Agro-Industrial Residues and Applications of Derived Extracts.

The world is confronted with the depletion of natural resources due to their unsustainable use and the increasing size of populations. In this context, the efficient use of by-products, residues and wastes generated from agro-industrial and food processing opens the perspective for a wide range of benefits. In particular, legume residues are produced yearly in very large amounts and may represent an interesting source of plant proteins that contribute to satisfying the steadily increasing global protein demand.