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Mandarina Bavaria is a "Special Flavor" hop variety, described as fruity, with pronounced mandarin and citrus, combined with traditional hoppy sensations. The relationship between fruity-citrus intensity and the volatile profile of dry-hopped beers was assessed in order to predict the sensory perception of those dry-hopped beers using the content of selected volatile compounds. For this purpose, two base beers (A and B) that presented statistical differences (p < 0.05) in the composition of volatile compounds and on the sensory perception were dry hopped with 3 g/L Mandarina Bavaria hop. Twenty-four volatiles from hop were quantified during 15 days of dry hopping, while the sensory perception was followed by a certified trained panel. The sensory perception of total hoppy content (in a scale from 0 to 5) can be estimated using a PLS equation (Q2 = 0.654): total hoppy = 1.8 + [myrcene (μg/L) × 7.5 × 10-3] + [2-methylbutyl-2-methylpropanoate (μg/L) × 4.2 × 10-3] + [linalool (μg/L) × 7.2 × 10-3] + [α-humulene (μg/L) × 2.3 × 10-3]). Successful models were also obtained to predict citrus (Q2 = 0.745), green fruit (Q2 = 0.598), and sweet fruit (Q2 = 0.626) characteristics of dry-hopped beers.

Peri-urban areas are territories that combine urban and rural features, being particularly vulnerable to wildfire due to the contact between human infrastructures and dense vegetation. Wildfires may cause considerable direct and indirect effects on the local water cycle, but the influence on groundwater quality is still poorly understood. The aim of this study was to characterize the chemistry of several springs connected to small public supply systems in a peri-urban area, following a large wildfire that took place in October 2017. Groundwater samples were collected in four springs that emerged within burned forests, while control samples were from one spring located in an unburned area. Sampling took place from October 2017 until September 2018, starting 15 days after the wildfire occurrence, to evaluate the influence of the time after fire and the effect of precipitation events on groundwater composition. Groundwater samples collected in burned areas presented increased content of sulfate, fluoride and nitrogen and variability in pH values. Iron, manganese and chromium contents also increased during the sampling period. Post-fire concentrations of polycyclic aromatic hydrocarbons (PAHs), mainly the carcinogenic ones, increased especially after intense winter and spring rain events, but the levels did not exceed the guideline values for drinking water.

Environmental health is increasingly compromised by persistent toxic substances, which may have serious implications in food safety and, thus, in human health. Polybrominated diphenyl ethers (PBDEs) are anthropogenic contaminants with endocrine disruption abilities and are commonly found in seafood, the main route of human exposure. Growing evidence points out that the human gut microbiota interacts with xenobiotics, which may lead to impairment of host homeostasis if functions of microbiota become compromised. The aim of this study was to ascertain if the physiological balance of human gut microbiome is affected by the presence and degree of exposure to PBDEs. Fermentation was performed in a batch closed-system using an inoculum made from fresh human stool. The volatolomic profile was analysed by solid-phase microextraction coupled to gas chromatography-mass spectrometry. Mesophilic, Gram-negative bacteria and coliforms were quantified by classic plating methods. Changes in the gut microbiome were evaluated after DNA extraction followed by deep sequencing of the 16S rDNA region. The exposure to PBDEs resulted in an imbalance in sulfur, short-chain fatty acids and aromatic organic compounds, changing the microbial volatolome in a dose- and time-dependent manner. Slight deviations in the microbial structure of human gut occurred in the presence of PBDEs, especially for high doses of exposure. For the first time, the impact of PBDEs on the microbial homeostasis of human gut microbiota was taken into consideration, revealing noteworthy modifications with serious health implications even at oral exposure doses considered as safe by worldwide regulatory entities. The research leading to these results received financial support from FEDER (Programa Operacional Competitividade e Internacionalização - COMPETE 2020), from PIDDAC through FCT/MCTES project POCI-01-0145-FEDER-028708 and from UID/QUI/50006/2019 with funding from FCT/MCTES. Rebeca Cruz thanks to FCT for the PhD grant SFRH/BD/101945/2014. António Marques thanks to FCT IF program. Miguel Faria acknowledges FCT the researcher contract. Sara C. Cunha also acknowledges FCT for the IF/01616/2015 contract.

The effect of five different vinegars, applied as a seasoning, on the formation of polycyclic aromatic hydrocarbons (PAH) in charcoal-grilled pork loin was investigated. PAH were assayed using acetonitrile based-extraction and high-performance liquid chromatography with fluorescence detection. Unseasoned samples presented a mean value of 31.47 ng g(-1) of PAH4 (sum of benz[a] anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene), near the maximum established by European Union (30 ng g(-1)). Significant reduction (p < .05) of PAH4 formation was observed in meat samples sprayed with vinegar. Elderberry vinegar exhibited the highest inhibition (82%), followed by white wine vinegar (79%), red wine and cider vinegars (66%), and fruit vinegar with raspberry juice (55%). The total phenolic content and antioxidant activities of vinegars had a moderate negative correlation with PAH4 formation, and 3rd degree polynomial equations had the best fitting performance to explain this relation. Spraying meat with these vinegars prior grill is an easy-to-apply strategy to limit the exposure to PAH.

The impact of bread fortification with β-glucans and with proteins/proteolytic enzymes from brewers’ spent yeast on physical characteristics was evaluated. β-Glucans extraction from spent yeast cell wall was optimized and the extract was incorporated on bread to obtain 2.02 g β-glucans/100 g flour, in order to comply with the European Food Safety Authority guidelines. Protein/proteolytic enzymes extract from spent yeast was added to bread at 60 U proteolytic activity/100 g flour. Both β-glucans rich and proteins/proteolytic enzymes extracts favoured browning of bread crust. However, breads with proteins/proteolytic enzymes addition presented lower specific volume, whereas the incorporation of β-glucans in bread lead to uniform pores that was also noticeble in terms of higher specific volume. Overall, the improvement of nutritional/health promoting properties is highlighted with β-glucan rich extract, not only due to bread β-glucan content but also for total dietary fibre content (39% increase). The improvement was less noticeable for proteins/proteolytic enzymes extract. Only a 6% increase in bread protein content was noted with the addition of this extract and higher protein content would most likely accentuate the negative impact on bread specific volume that in turn could impair consumer acceptance. Therefore, only β-glucan rich extract is a promising bread ingredient.

Citrus fruit peel comprises a pleasant mix of volatile compounds together with fibers, nutrients, and bioactive compounds. Therefore, it has great potential for use as a food ingredient. Studies evaluating the volatile composition of citrus peel flours are limited for most citruses. The goal of this study was to characterize, by HS-SPME/GC-MS, the volatile profile of citrus peel flours made from fruits commonly grown in Brazil. Two composite samples of ten types of citrus peel flours from consecutive harvests were evaluated. 69 volatile compounds were assigned, 49 in Tahiti acid lime, 49 in Sicilian lemon, 37 in Persian lime, 34 in Italian tangerine and oval kumquat, 33 in Valencia orange, 32 in Baia orange and round kumquat, 28 in Blood-of-Mombuca orange and 26 in Lima orange. 26 major compounds represented 93-99% of the total chromatogram peak area. Terpenic compounds were predominant in all samples, especially monoterpenes (about 48-97% of the total chromatogram peak area), while lower proportions of aldehydes (0.2-16.1%), monoterpene alcohols (0.4-11.8%) and esters (0.0-7.7%) were observed. Even though a few compounds like limonene, β-myrcene, linalool, α-pinene and valencene were detected in all citrus, volatile compounds followed specific patterns in the different citruses, with a clear distinction among them, especially between lemon flours and the remaining flours. The variety of volatile profiles and singular specific volatolomic signatures in citrus peels can be explored for different applications related to food flavoring and preservation, and promotion of good health. These aspects should be thoroughly investigated in future studies.

Dietary fibre is easily available in plant foods. However, western diet frequently does not meet recommended levels. Fibre supplementation of bread is an opportunity due to its daily consumption. In this work, fibre-enriched extracts were recovered from elderberry (EE), orange (OE), pomegranate (PE), and spent yeast (YE), and their fibre composition was characterized. The impact of wheat flour replacement by different fibre extract amounts on dough properties indicates that (1) optimum water absorption increased with higher concentrations of OE, PE, and YE; (2) development time for EE, PE, and YE was shortened, while the opposite was observed for OE; (3) the onset of starch gelatinization and maximum tanδ increased significantly with 36% EE and 4% PE; (4) protein structure, observed with confocal laser scanning microscopy, was modified by addition of extracts; and (5) maximum and final dough height decreased significantly, except for 4% EE. Wheat flour replacement also had an impact on bread parameters, since (1) volume and specific volume decreased at the highest concentrations in every extract; (2) significant changes were observed in crumb texture and structure, at higher extract concentrations. Multivariate PLS regression highlights the relationships between dough and bread data.

The nutritional value and digestibility of leaf proteins is still a major issue. Therefore, the goal of this work was to optimize the production of a protein concentrate (PC) from Moringa Oleifera defatted leaves (MODL) by enzymatic extraction using Viscozyme L and evaluate its nutritional quality and digestibility. Protein extraction conditions were screened using a factorial design. Enzyme/Substrate ratio and pH had no significant effect, whereas, the significant variables, temperature (°C), enzyme concentration and incubation time (h) were optimized by central composite design (CCD). PC contained 55.7% of proteins with a balanced amino acid profile when compared with MODL and higher content of essential amino acids (EAAs) (488.6-402.9 mg/g of protein respectively). Improvement on protein digestibility was observed for MODL compared to PC (64.75-99.86% respectively) and higher protein digestibility corrected amino acid score (PDCAAS) (62.10-91.41% respectively). PC meets FAO protein quality expectations. Highlights: Sustainable extraction of leaf proteins with the low temperatures/incubation times; Moringa protein concentrate has higher essential amino acids index than whole leaves; Protein isolation and concentration enhanced its nutritional value and digestibility. This work received financial support from FEDER funds and National Funds (FCT/MEC, Fundação para a Ciência e Tecnologia and Ministério da Educação e Ciência) project PTDC/OCE-ETA/32567/2017- MOR2020. Tassadit Benhammouche thanks the PhD Grant awarded by the University of Porto under the Erasmus + Program in coordination with University of Bejaia Algeria. info:eu-repo/semantics/publishedVersion

The practice of dry-hopping has been used by the brewing industry to obtain beers with increased contents of flavor and bitterness compounds. Notwithstanding this, other compounds such as α-acids (AA) and xhanthohumol (XN) are co-extracted influencing the final characteristics of the beer, particularly its beneficial bioactivity. In this context a model for the understanding of AA and XN extraction by dry-hopping is proposed. The varieties Chinook (CHI), East Kent Goldings (EKG) and Tettnanger (TET) were assayed and robust statistical approaches were applied for data interpretation. Concentration of AA in beers post-maturation reached values higher than 20 mg/L using 2.8 g/L of CHI hops and 10 days of maturation. For XN, a similar behavior was verified. The maximum efficiency of AA and XN extraction (transfer rate) were reached at 13.5 days with dose rates of 147 and 13.9 mg/L, respectively. Authors are grateful to the project UID/QUI/50006/2013-POCI/01/0145/FEDER/007265 with support from FCT/MEC through national funds and co-financed by FEDER, under the Partnership Agreement PT2020. M. A. Faria is grateful for research contract from NORTE-01-0145-FEDER-000011 – FoodNanoHealth and A. Melo wishes to thank the Fundação para a Ciência Tecnologia for grants SFRH/BPD/86898/2012. info:eu-repo/semantics/publishedVersion

Mycotoxins can contaminate poultry production via fungal infection of feeds. The impact of different cooking methods on mycotoxins stability and bioaccessibility is scarcely studied. Recent cooking practices such as the use of roasting bags along with some seasonings to cook chicken have become a trend to maintain the tenderness of the meat. This study evaluated the impact of oven roasting and microwaving of chicken breast muscles, with/without roasting bags and/or herbs addition on the stability and bioaccessibility of the 10 prevalent mycotoxins. Cooking itself reduced mycotoxins content, while using bags did not confer any advantage; adding herbs reduced mycotoxins content by up to 60%, but also appeared to increase their bioaccessibility. Thus, strategies to reduce their increased bioaccessibility should be the subject of future research. Notwithstanding, adding herbs prior to cooking could be used as a mitigation strategy to reduce mycotoxins in meat.

In this work, wheat bread was fortified with fibre enriched extracts recovered from agroindustry by-products, namely, elderberry skin, pulp and seeds (EE); orange peel (OE); pomegranate peel and interior membranes (PE); and spent yeast (YE). The impact of this fortification on the total and bioaccessible mineral composition of wheat breads, estimated mineral daily intake, and the relationship between bioaccessibility and dietary fibre was evaluated. Fortification with OE, EE, and PE improved the content of essential minerals in bread when compared to control bread. The exception was bread fortified with YE, which presented a mineral content similar to control bread, but its mineral bioaccessibility was significantly higher than in all the other bread formulations. The opposite was observed for PE bread, which presented a significant reduction of bioaccessible minerals. We concluded that the origin of the fibre rich extract must be carefully selected, to avoid potential negative impact on mineral bioaccessibility.

The impact of bread fortification with dry spent yeast from brewing industry on physical, chemical and sensorial characteristics of home-made bread was evaluated with the goal of increasing its β-glucan content. A serving of 50 g of bread fortified with dry spent yeast increased β-glucan intake from 65 to 125 mg, which is within the guidelines suggested by European Food Safety Authority. Although this fortification darkened the crumb and increased crumb and crust springiness and had impact on volatile profile, concerning key odours only hexanal presented a significant increase in fortified bread. Two machine types (with 1 or 2 paddles) were tested but had a minor impact on bread characteristics. Descriptive analyses performed by a trained panel showed no significant differences in sensorial attributes. Dry spent yeast can be used as ingredient in home-made bread to increase β-glucan intake, and contribute to valorisation of this brewing by-product. Fil: Martins, Zita Emanuela. Universidade do Porto; Portugal Fil: Erben, Melina. Universidade do Porto; Portugal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Gallardo, Anabella Elisabet. Universidade do Porto; Portugal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Silva, Ricardo. Universidade do Porto; Portugal Fil: Barbosa, Inês. Universidade do Porto; Portugal Fil: Pinho, Olivia. Universidade do Porto; Portugal Fil: Ferreira, Isabel M. P. L. V. O.. Universidade do Porto; Portugal

Cows' and donkey milks (raw and thermally processed) and respective whey were analysed for quantification of major proteins. Two different chromatographic approaches, size exclusion (SE-HPLC) and reversed-phase high performance liquid chromatography (RP-HPLC) both coupled to UV detection were used. Usefulness of these methods for routine control of the effect of thermal processing was evaluated. The external standard method was used to calibrate the SE-HPLC and RP-HPLC systems. Concerning quantification of β-lactoglobulin (β-lg), α-lactalbumin (α-la), lysozyme (lys), and total casein (cn), no significant differences between results obtained by SE-HPLC and by RP-HPLC (t-test, P>0·05) were observed for raw milks and whey. Heating of cows' milk promoted aggregation of denatured proteins as observed by SE-HPLC, whereas α-la and β-lg from donkey milk were stable to thermal processing at 100°C (5 min). Lys was quantified in donkey raw milk and whey however, in thermally processed donkey milk lys was denatured and could not be quantified by HPLC.