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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 Arthrospira platensis (spirulina), Chlorella vulgaris, Tetraselmis chui, or Nannochloropsis oceanica at two levels of addition (1.5% and 3.0%). The impact of microalgae species and an addition level on the amino acid profile and protein in vitro digestibility of the vegetable creams was investigated. The addition of microalgae to vegetable creams improved the protein content and the amino acid nutritional profile of vegetable creams, whereas no significant differences were observed in protein digestibility, regardless of the species and level of addition, indicating a similar degree of protein digestibility in microalgae species despite differences in their protein content and amino acid profile. This study indicates that the incorporation of microalgae is a feasible strategy to increase the protein content and nutritional quality of foods. [ABSTRACT FROM AUTHOR]

The beneficial effects of an insect-based diet on human health and, in particular, the regulatory ability of digested insects' proteins on the glycaemic response in humans are topics that need to be investigated deeper. In this work, we performed an in vitro study on the modulatory activity of gastrointestinal digested black soldier fly (BSF) prepupae on the enterohormone GLP-1 and its natural inhibitor, DPP-IV. We verified whether actions intended to valorise the starting insect biomass, i.e., insect-optimised growth substrates and prior fermentation, can positively impact human health. Our results highlight that the digested BSF proteins from all the prepupae samples had a high stimulatory and inhibitory ability on the GLP-1 secretion and the DPP-IV enzyme in the human GLUTag cell line. Gastrointestinal digestion significantly improved the DPP-IV inhibitory capacity of the whole insect protein. Moreover, it was seen that optimised diets or fermentation processes preceding the digestion, in any case, did not positively affect the efficacy of the answer. BSF was already considered one of the edible insects more suitable for human consumption for its optimal nutritional profile. The BSF bioactivity here shown, after simulated digestion, on glycaemic control systems makes this species even more promising. [ABSTRACT FROM AUTHOR]

In recent years, due to the significant increase in hypertension, peptides which are able to reduce blood pressure have gained special interest by scientific research and food industry. Several bioactive peptides with ascertained ACE-inhibitory activity have been found in Parmigiano Reggiano (PR) cheese and/or mixtures deriving from its digestion in vitro, and this may be predictive of its potential antihypertensive effect in vivo. This study investigated the long-term effect of feeding (PR) cheese on blood pressure (BP) of spontaneously hypertensive rats (SHRs). A total of 30 male SHRs, 13 weeks old, were subdivided into 6 groups balanced for body weight and BP, to receive daily dietary supplementation with: 0.1–0.2–0.4–0.6 g PR/rat, captopril, and water. Systolic and diastolic BP were recorded every two weeks, for 10 weeks. Blood samples were collected at the end of the trial. Dietary integration with PR led to a transitory reduction in rats' pressure in the first 35 days of treatment and pressure decreased in a dose-dependent manner. In the second part of the study, the beneficial effect of PR antihypertensive peptides may have been masked and reduced by the increase in BP of rats linked to the rise in age of animals. No PR derived peptides were detected in rats' serum. Highlights: Parmigiano Reggiano (PR) cheese led to a transitory reduction in rats' pressure in the first 35 days of treatment. This effect was PR dose dependent. The highest amounts of PR tested did not increase both systolic and diastolic blood pressures of hypertensive rats. [ABSTRACT FROM AUTHOR]

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. Non-compliant green coffee beans showed higher amounts of polyphenols, flavanols, flavonoids, and caffeine than coffee silverskins (which were richer in tannins). The enzymatic extraction of non-compliant coffee green beans produced extracts with a good protein content and with a consistent quantity of polyphenols. The extract showed antioxidant, antityrosinase, and antimicrobial activity, thus representing a promising strategy to recover defective green coffee beans. The antioxidant and antimicrobial activity of coffee silver skins is lower than that of non-compliant coffee green beans extracts, while the antityrosinase activity is comparable. [ABSTRACT FROM AUTHOR]

Insects are becoming increasingly relevant as protein sources in food and feed. The Black Soldier Fly (BSF) is one of the most utilized, thanks to its ability to live on many leftovers. Vegetable processing industries produce huge amounts of by-products, and it is important to efficiently rear BSF on different substrates to assure an economical advantage in bioconversion and to overcome the seasonality of some leftovers. This work evaluated how different substrates affect the protein and amino acid content of BSF. BSF prepupae reared on different substrates showed total protein content varying between 35% and 49% on dry matter. Significant lower protein contents were detected in BSF grown on fruit by-products, while higher contents were observed when autumnal leftovers were employed. BSF protein content was mainly correlated to fibre and protein content in the diet. Among amino acids, lysine, valine and leucine were most affected by the diet. Essential amino acids satisfied the Food and Agricultural Organization (FAO) requirements for human nutrition, except for lysine in few cases. BSF could be a flexible tool to bio-convert a wide range of vegetable by-products of different seasonality in a high-quality protein-rich biomass, even if significant differences in the protein fraction were observed according to the rearing substrate. [ABSTRACT FROM AUTHOR]

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. In particular, 20 wheels were produced with conventional (18 days, 10 wheels) and shorter (12 days, 10 wheels) brining steps. In every group, wheels were studied at two different ripening times, 15 and 30 months. A shorter brining time resulted in an average 12% decrease in salt content. A full characterization of free amino acids and peptides was performed by LC-MS on all samples. Free amino acids and peptides, as expected, increased with ripening, due to proteolysis, with samples having low salt content showing a slightly faster increase when compared to standard ones, hinting to a slightly accelerated proteolytic process. Nonetheless, low-salt and conventional cheeses shared similar sensory profiles at both ripening times. [ABSTRACT FROM AUTHOR]

The reasons behind the increasing prevalence of celiac disease (CD) worldwide are still not fully understood. This study adopted a multilevel approach (in vitro, ex vivo, in vivo) to assess the potential of gluten from different wheat varieties in triggering CD. Peptides triggering CD were identified and quantified in mixtures generated from simulated gastrointestinal digestion of wheat varieties (n = 82). Multivariate statistics enabled the discrimination of varieties generating low impact on CD (e.g., Saragolla) and high impact (e.g., Cappelli). Enrolled subjects (n = 46) were: 19 healthy subjects included in the control group; 27 celiac patients enrolled for the in vivo phase. Celiacs were divided into a gluten-free diet group (CD-GFD), and a GFD with Saragolla-based pasta group (CD-Sar). The diet was followed for 3 months. Data were compared between CD-Sar and CD-GFD before and after the experimental diet, demonstrating a limited ability of Saragolla to trigger immunity, although not comparable to a GFD. Ex vivo studies showed that Saragolla and Cappelli activated immune responses, although with great variability among patients. The diverse potential of durum wheat varieties in triggering CD immune response was demonstrated. Saragolla is not indicated for celiacs, yet it has a limited potential to trigger adverse immune response. [ABSTRACT FROM AUTHOR]

Worldwide, thousands of insect species are consumed as food or are used as feed ingredients. Hermetia illucens, 'black soldier fly', is one of them, and a large amount of puparia and dead adults flies are accumulated during rearing. These materials represent important wastes but no studies are still present in the literature regarding their functional properties and potential reuse. Lactic acid bacteria (LAB) are a heterogeneous group of bacteria contributing to various industrial applications, ranging from food fermentation, chemicals production to pharmaceuticals manufacturing. A LAB feature of industrial interest is their ability to produce antimicrobial metabolites. Considering the scientific and commercial interest in discovering novel antimicrobials, this work will be direct towards fermentation of insect-derived biomasses: puparia and adults insect at the end of life cycle. To the best of our knowledge, the in vitro antimicrobial activity of fermented insects is tested for the first time. This study aimed also to evaluate differences in the composition between fermented and unfermented insects, and to study whether the fermentation and the type of LAB used played a crucial role in modifying the composition of the substrate. Results firstly highlighted fermentability of this species of insects, showed that fermented black soldier flies puparium possess a high antimicrobial activity against tested pathogens. Moreover, result of chemical composition showed that fermented biomass had a higher percentage of fat and a more complex fatty acids profile. [ABSTRACT FROM AUTHOR]

While durum wheat is a major food source in Mediterranean countries, storage (i.e., gluten) proteins are however responsible for celiac disease (CD), a serious autoimmune disease that occurs in genetically predisposed subjects. Different gluten epitopes—defined as "immunogenic" (IP) and "toxic" (TP) peptides—are involved in the pathology and their content in wheat grain depends on environmental and genetic factors. Detection of IP and TP is not trivial, and no work has been conducted so far to identify the genomic regions associated with their accumulation in wheat. In the present study, a genome-wide association study was performed on a durum wheat collection to identify marker–trait associations (MTAs) between 5730 high quality SNPs and the accumulation of CD-related peptides and gluten protein composition measured in two consecutive cropping seasons (2015/2016 and 2016/2017). High-molecular-weight glutenin subunits (HMW-GS) were more stable between the two years, and differences in total gluten proteins were mainly due to low-molecular-weight glutenin subunits (LMW-GS) and accumulation of gliadins. In the first instance, association tests were conducted on yellow pigment content (YP), a highly inheritable trait with a well-known genetic basis, and several significant MTAs were found corresponding to loci already known for being related to YP. These findings showed that MTAs found for the rest of the measured traits were reliable. In total, 28 significant MTAs were found for gluten composition, while 14 were found to be associated with IP and TP. Noteworthy, neither significant (−log10p > 4.7) nor suggestive (−log10p > 3.3) MTAs for the accumulation of CD-triggering epitopes were found on Gli-A1/Glu-A3 and Gli-B1/Glu-B3 loci, thus suggesting regulatory rather than structural gene effect. A PBF transcription factor on chromosome 5B, known to be involved in the regulation of the expression of CD-related peptides, was identified among the positional candidate genes in the LD-decay range around significant SNPs. Results obtained in the present study provide useful insights and resources for the long-term objective of selecting low-toxic durum wheat varieties while maintaining satisfactory gluten quality. [ABSTRACT FROM AUTHOR]

Protein hydrolysates from lesser mealworm (Alphitobius diaperinus, LM) were obtained by enzymatic hydrolysis with protease from Bacillus licheniformis. A preliminary test performed for five hours of hydrolysis generated an insect protein hydrolysate with 15% of degree of hydrolysis (DH), optimum solubility property and oil holding capacity, but emulsifying and foaming ability were completely impaired. In order to investigate the potential implication of DH on techno-functional properties, a set of protein hydrolysates with a different DH was obtained by sub-sampling at different time points during three hours of enzymatic hydrolysis process. An increase in DH% had positive effects on the solubility property and oil holding ability, while a reduced emulsifying ability was observed up to five hours of hydrolysis. These results demonstrated that the enzymatic hydrolysis, if performed under controlled conditions and not for a long period, represents a valid method to extract high quality protein from insects with tailored techno-functionality, in order to produce tailored ingredients for feed and food purpose. [ABSTRACT FROM AUTHOR]

The high temperatures used in the production of milk may induce modifications in proteins structure. Due to occurrence of the Maillard reaction, lactose binds lysine residues in proteins, affecting the nutritional value. Milk is also an important source of allergenic proteins (i.e., caseins, β-lactoglobulin and α-lactalbumin). Thus, this modification may also affect the allergenicity of these proteins. Focusing on milk whey proteins, a screening on different Ultra High Temperatures (UHT) and pasteurized milk samples was performed to identify lactosylation sites, in particular in protein known epitopes, and to verify the correlation between lactosylation and the harshness of the treatment. Whey proteins were extracted from milk samples after caseins precipitations at pH 4.6 and, after chymotryptic and tryptic in solution digestion, peptides were analysed by UPLC-MS and LTQ-Orbitrap. Results show the presence of lactosylated lysine residues in several known epitopes. Then, a β-lactoglobulin epitope was selected and synthesized by solid phase synthesis followed by in solution lactosylation, obtaining high reaction yields and purities. The synthesis of lactosylated allergenic epitopes, described here for the first time, is a useful tool for further studies on the technological impacts on food allergenicity. [ABSTRACT FROM AUTHOR]

Parmigiano–Reggiano (PR) is a worldwide known Italian, long ripened, hard cheese. Its inclusion in the list of cheeses bearing the protected designation of origin (PDO, EU regulation 510/2006) poses restrictions to its geographic area of production and its technological characteristics. To innovate the Parmigiano–Reggiano (PR) cheese manufacturing chain from the health and nutritional point of view, the output of defatted PR is addressed. Two defatting procedures (Soxhlet, and supercritical CO2 extraction) were tested, and the obtained products were compared in the composition of their nitrogen fraction, responsible for their nutritional, organoleptic, and bioactive functions. Free amino acids were quantified, and other nitrogen compounds (peptides, proteins, and non-proteolytic aminoacyl derivatives) were identified in the extracts and the mixtures obtained after simulated gastrointestinal digestion. Moreover, antioxidant and angiotensin converting enzyme (ACE) inhibition capacities of the digests were tested. Results obtained from the molecular and biofunctional characterization of the nitrogen fraction, show that both the defatted products keep the same nutritional properties of the whole cheese. [ABSTRACT FROM AUTHOR]

Insects are considered a suitable alternative feed for livestock production and their use is nowadays regulated in the European Union by the European Commission Regulation No. 893/2017. Insects have the ability to grow on a different spectrum of substrates, which could be naturally contaminated by mycotoxins. In the present work, the mycotoxin uptake and/or excretion in two different insect species, Alphitobius diaperinus (Lesser Mealworm, LM) and Hermetia illucens (Black Soldier Fly, BSF), grown on naturally contaminated substrates, was evaluated. Among all the substrates of growth tested, the Fusarium toxins deoxynivalenol (DON), fumonisin 1 and 2 (FB1 and FB2) and zearalenone (ZEN) were found in those based on wheat and/or corn. No mycotoxins were detected in BSF larvae, while quantifiable amount of DON and FB1 were found in LM larvae, although in lower concentration than those detected in the growing substrates and in the residual fractions. Mass balance calculations indicated that BSF and LM metabolized mycotoxins in forms not yet known, accumulating them in their body or excreting in the faeces. Further studies are required in this direction due to the future employment of insects as feedstuff. [ABSTRACT FROM AUTHOR]

In this study we investigated the oligopeptide pattern in fermented cocoa beans and derived products after simulated gastrointestinal digestion. Peptides in digested cocoa samples were identified based on the mass fragmentation and on the software analysis of vicilin and 21 KDa cocoa seed protein sequences, the most abundant cocoa proteins. Quantification was carried out by liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI-MS) using an internal standard. Sixty five peptides were identified in the digested samples, including three pyroglutamyl derivatives. The in vitro angiotensin-converting enzyme (ACE)-inhibitory activity of cocoa digests were tested, demonstrating a high inhibition activity, especially for digestates of cocoa beans. The peptides identified were screened for their potential ACE inhibitory activity through an in silico approach, and about 20 di-, three- and tetra-peptides actually present in our samples were predicted as active. Two of the potentially active peptides were chemically synthesized and then assessed for their inhibitory activity by using the ACE in vitro assay. These peptides demonstrated an ACE inhibitory activity, however, that was too weak to explain alone the high activity of cocoa digestates, suggesting a synergic effect of all cocoa peptides. As a whole, results showed that an average chocolate portion (30 g) ensures an amount of peptides after digestion that, assuming complete absorption, could reach almost a complete inhibition of ACE. [ABSTRACT FROM AUTHOR]