Browsing by Author "Pereira, Maria J."
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- Can sardine cooking wastewaters modulate European seabass feed intake?Publication . Resende, Daniela; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.; Velasco, CristinaThe goal of this work was to evaluate three extracts from sardine cooking waters, a by-product of the canning industry, as feed intake modulators, when included in highly vegetable diets, which often display low intake by carnivorous species. Sardine cooking waters, supplemented with acorn extract (Aroma 3) were processed, by vacuum condensation (Aroma 1) or liquid/liquid extraction with soybean oil (Aroma 2). Aromas were then included in a low-fishmeal diet (12.5%), achieving equal amounts of 1-penten-3-ol (2 μg/g). Diets were assigned to triplicate groups of 15 European seabasses (initial weight 95.7 ± 13.5 g) fed twice daily until apparent satiation in a recirculating saltwater system. Growth, nutrient utilization and wholebody composition were assessed after 18 weeks, along with both instrumental texture and color measurements and a sensory analysis of fillets. In parallel, a short-term trial was performed, in which fish fed the experimental diets were sampled 2 or 6 hours after the first feeding, for evaluation of neuropeptides involved in intake regulation. No significant differences among diets were found in fish final weight, specific growth rate, whole-body composition, and nutrient gain. Diet with Aroma 2 displayed a significantly higher voluntary feed intake than the Aroma 3, although both remained similar to the non-supplemented control. No differences on organoleptic properties were found by the panelists in the sensory analysis. No differences were found on neuropeptides expression 2h after feeding, but expression of orexigenic agrp2 was increased 6h post-feeding in all supplemented diets, in the telencephalon. Overall, results suggest that the aromas can modulate feed intake, but further optimization of incorporation levels should be performed as to see a clear effect on fish growth.
- Dietary inclusion of sardine cooking waters: impact on appetite regulation, growth and sensory properties of European seabassPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.Introduction Plant-based ingredients have been considered suitable options for replacing marinebased ones in aquafeeds (Naylor et al., 2021), but this may compromise diet palatability (Geurden et al., 2013), potentially affecting fish growth and flesh quality. To overcome this, feed attractants have been suggested. These compounds, like alcohols, aldehydes, and organic acids, were reported to stimulate intake in mammals (Chen et al., 2017; Takács et al., 2018). They can be obtained from agri-food by-products, within a circular economy framework. One example is the 9 m3 liquid waste generated by the canning industry per tonne of canned fish (Ferraro et al., 2013). The objective of this work was to extract aromas from the effluent waters of a canning industry and incorporate them in plant-based diets for European seabass. The aim was to evaluate their potential to modulate intake, growth and fillet organoleptic characteristics. Materials and methods Sardine cooking wastewaters were collected and either used directly (CW-A) or after processing by vacuum distillation (VD-A) or liquid/liquid extraction with soybean oil (LLE-A). Although the resulting extracts had different chemical profiles, the most abundant compound in all fractions was the 1-penten-3-ol. This was hence selected as marker and extracts containing 2 μg/g of this compound were incorporated in isolipidic and isoproteic diets (CW, VD and LLE) for European seabass. A non-supplemented diet was used as control (CTRL). Each diet was assigned to triplicate fish groups (initial weight 95.7 ± 13.5 g), hand-fed twice daily until apparent satiation in a recirculating saltwater system at 21 °C. After 18 weeks, growth performance and nutrient utilisation were evaluated. Flesh colour and texture were assessed instrumentally and by sensory analysis using a consumer panel. Moreover, the expression of neuropeptides involved in feed intake regulation (neuropeptide y – npy, agouti-related peptide – agrp2, cocaine and amphetamine-related transcript – carpt2 and pro-opiomelanocortin – pomca) in the brain was analysed. Metabolites in plasma and liver of fish were also quantified. Results and Conclusions Fish fed LLE displayed a significantly higher voluntary feed intake than those fed the CW diet, although neither differed from CTRL. LLE also resulted in increased feed conversion ratio. Final weight, whole-body composition, and nutrient gain were similar among diets. The expression of intake-regulating neuropeptides was not significantly affected by diets, but a slight upregulation of the orexigenic npy was observed for the LLE diet. In addition, fish fed this diet displayed the lowest plasmatic glucose and highest hepatic glucose and triglycerides values, although the remaining metabolites (lactate, non-esterified fatty acids, cholesterol and glycogen) were unaffected. Thus, the changes in feed intake are probably due to a combined effect of the homeostatic (nutrient-driven) and hedonic (pleasure-driven) regulation. No differences were found in skin or muscle colour among treatments. Despite a lower hardness in fillets of fish fed LLE when compared to those fed CTRL, no significant differences were perceived by the sensory panel; global liking of samples was similar among treatments, being all generally well accepted. Additionally, the samples’ taste and odour were characterized as “characteristic fish” and “soft” for all treatments. Overall, results suggest that aromas from sardine cooking wastewaters can modulate feed intake, but further optimization of either the processing and/or incorporation levels seems required to maximize their effectiveness as feed intake stimulants for application in aquafeeds.
- Evaluation of sardine cooking wastewaters as feed intake modulators for European seabass dietsPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M.P.There has been a tendency to replace marine ingredients in aquafeeds, namely fishmeal, with more sustainable vegetable protein sources. However, this replacement often reduces diet palatability, with a subsequent decrease in feed intake and growth and/or alteration of flesh quality. The goal of this work was to evaluate the effectiveness of aromatic mixtures extracted from sardine cooking wastewaters, a by-product of the canning industry, as feed intake stimulants in highly vegetable diets for European seabass (Dicentrarchus labrax). Sardine cooking wastewaters were either used directly (CW) or after processing by vacuum condensation (VC) or liquid/liquid extraction with soybean oil (LLE). The chemical profile of the extracts differed, but the most abundant compound identified in all extracts was the 1-penten-3-ol, hence selected as marker and included at 2 μg/g in plant protein-based diets. Thus, four isolipidic and isoproteic diets (one for each aroma sample and a non-supplemented control) were produced. Diets were assigned to triplicate groups of fish (initial weight 95.7 ± 13.5 g) that were hand-fed twice daily until apparent satiation in a recirculating saltwater system at 21 °C. After 18 weeks, fish growth performance and nutrient utilisation were evaluated. Flesh colour and textural properties were assessed instrumentally and by sensory analysis using a consumer panel. Fish fed LLE displayed a significantly higher voluntary feed intake than those fed diet CW, although neither differed from the control. LLE diet also resulted in increased feed conversion ratio, but final weight, daily growth rate, whole-body composition, and nutrient gain remained similar among diets. No differences were also found in fish skin or muscle colour. Despite a lower hardness in fillets of fish fed LLE when compared to those fed the control, no significant differences could be perceived by the sensory panel; global liking of samples was similar among treatments, being all generally well accepted. Additionally, the taste and odour of all samples was similar with a “characteristic fish” and “soft” odour/taste. Overall, results suggest that the aromas from sardine cooking wastewaters can modulate feed intake, but further optimization of either the processing and/or incorporation levels seems required to potentiate their effectiveness on fish growth. The physiological mechanisms underlying the modulation of appetite also merits further evaluation.
- Exploring the influence of sardine cooking water extracts on the short-term regulation of feed intake in European seabassPublication . Resende, Daniela; Pereira, Maria J.; Sá, Tiago; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.; Velasco, CristinaIntroduction In fish, feed intake regulation is mediated by an interaction between homeostatic and hedonic signals (Soengas et al., 2018). The homeostatic control relates to biological needs regarding nutrients and energy (Soengas, 2021). On the other hand, the hedonic control is associated with reward-based routes, which are triggered by highly palatable food (Díaz-Rúa et al., 2022). Hedonic control may override homeostatic and maintain a drive to eat, due to the sensory pleasure felt by eating. Increasing the palatability of diets, such as those with high levels of plant-based ingredients, is therefore an important matter in aquaculture, as to achieve the best growth performance of fish. In addition, to evaluate the potential of a diet to affect the hedonic regulation of feed intake, long-term growth trials may be inadequate, since the need to maintain nutrient and energy homeostasis becomes more relevant over time. In parallel, the habituation effect to the diets occurs and masks the impact of diet palatability. Thus, studying feed intake stimulants, preferably obtained from by-products (considering a circular economy approach), on short-term trials may shed light on their impact on diet palatability and hedonic regulation of feed intake. In this work, we evaluated aromatic extracts from sardine cooking wastewaters as feed intake stimulants in plant-based diets for European seabass, focusing on the first feeding response towards the experimental diets. Materials and methods Sardine cooking wastewaters were collected and either tested directly (CW-A) or after vacuum distillation (VD-A) or after liquid/liquid extraction with soybean oil (LLE-A), resulting in distinct chemical profiles. The most abundant compound in the three extracts was 1-penten-3-ol, being thus chosen as marker and included at 2 μg/g in isolipidic and isoproteic diets (CW, VD, LLE). A practical plant-based diet (12.5% fishmeal and 4% fish oil) without any supplementation was used as control. Each diet was assigned to six homogeneous groups of European seabass juveniles (96 g). Fish were sampled 2 and 6 hours after a single first meal distributed to apparent satiation. Metabolites including glucose, lactate, cholesterol and non-esterified fatty acids were quantified in the plasma. Additionally, the mRNA abundance of neuropeptides involved in the regulation of feed intake, namely neuropeptide Y (npy), agouti-related peptide (agrp2), cocaine and amphetamine-related transcript (carpt2) and pro-opiomelanocortin (pomca) was quantified in the hypothalamus and telencephalon. Results and Conclusions Feed intake after the first meal was significantly higher for the control diet than for the supplemented diets. No significant differences on plasma metabolites were observed. Although the expression of neuropeptides involved in feed intake regulation was statistically similar among diets and sampling points, LLE and VD diets displayed the lowest expression of the agrp2 in the telencephalon, whilst LLE diet led to the highest expression of pomca, 2 hours after feeding. The similar profile of plasma metabolites among diets suggests that the regulation of feed intake in the tested fish was driven more by hedonic factors, such as reward or pleasure-driven, rather than homeostatic factors, such as nutrient-driven. The slightly lower expression of orexigenic (inducing feed intake) neuropeptide agrp2 in fish and higher expression of anorexigenic (supressing feed intake) neuropeptide pomca may be regulating factors associated with decreased feed intake observed in fish fed LLE and CW diets, but other factors might have also contributed to such results. Overall, the sardine cooking wastewaters extracts, in the tested concentration, had no positive effect on the short-term feed intake response of European seabass, which suggests that feed palatability was not enhanced. Further optimization of the extracts’ production process, and/or inclusion levels in diets should be considered in both short and long-term trials to improve effectiveness of the extracts as feed attractants.
- Incorporating sardine cooking water aromas into plant-based diets for european seabass: effects on appetite regulation, growth and sensory properties of fish fleshPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luisa M. P.Sardine cooking wastewaters are by-products of the canning industry with great potential for valorisation. We have hypothesized that they can be a source of aromas to enhance appetite when added to plant-based diets. The poor palatability of such diets often described in carnivorous species poses a recurring problem in fish farming, with harsh consequences on fish growth performance and flesh quality. Aromas from sardine cooking wastewaters were collected without processing (CW-A), processed through vacuum distillation (VD-A), or processed through liquid/liquid extraction with soybean oil (LLE-A) into plant-based diets. Each aroma was added to a plant-protein based diet for European seabass, at a concentration of 2 μg of 1-penten-3-ol/g diet, resulting in 3 experimental diets (CW, VD and LLE). A non-supplemented diet was used as a control. Each diet was assigned to triplicate fish groups (initial weight 95.7 g), that were hand-fed twice daily until apparent satiation in a recirculating saltwater system at 21 °C. After 18 weeks, fish growth performance and nutrient utilisation were evaluated. The expression in the brain of neuropeptides involved in feed intake regulation was also analysed. Moreover, flesh colour and texture were assessed instrumentally and by sensory analysis using a consumer panel. Fish fed LLE displayed a significantly higher feed intake than those fed CW which was correlated with an increased neuropeptide Y expression in the hypothalamus. However, LLE slightly hindered lipid metabolism, leading to lower available glucose and resulting in statistically similar final weights among diets. Despite variations in fillet hardness, the sensory panel revealed similar overall liking across all treatments. The findings indicate that aromas from sardine cooking wastewaters can modulate feed intake, but further refinement in processing or incorporation levels is required to potentiate their efficacy.
- Multi-trait analysis of post-harvest storage in rocket salad (Diplotaxis tenuifolia) links sensorial, volatile and nutritional dataPublication . Spadafora, Natasha D.; Amaro, Ana L.; Pereira, Maria J.; Müller, Carsten T.; Pintado, Manuela; Rogers, Hilary J.Rocket salad (Diplotaxis tenuifolia; wild rocket) is an important component of ready to eat salads providing a distinct peppery flavour and containing nutritionally relevant compounds. Quality deteriorates during post-harvest, in relation to time and storage temperature amongst other factors. Volatile organic compounds (VOCs) are easily measurable from rocket leaves and may provide useful quality indicators for e.g. changes in isothiocyanates derived from nutritionally important glucosinolates. VOC profiles discriminated storage temperatures (0, 5 and 10°C) and times (over 14days). More specifically, concentrations of aldehydes and isothiocyanates decreased with time paralleling a fall in vitamin C and a reduction in sensorial quality at the two higher temperatures. Sulphur containing compounds rise at later time-points and at higher temperatures coincident with an increase in microbial titre, mirroring a further drop in sensorial quality thus indicating their contribution to off-odours.
- Multitrait analysis of fresh-cut cantaloupe melon enables discrimination between storage times and temperatures and identifies potential markers for quality assessmentsPublication . Amaro, Ana L.; Spadafora, Natasha D.; Pereira, Maria J.; Dhorajiwala, Rakhee; Herbert, Robert J.; Muller, Carsten T.; Rogers, Hilary J.; Pintado, ManuelaFresh-cut cantaloupe melon is valued for its aroma but is highly perishable. Temperature of storage (typically 0-5°C) is critical for maintaining fresh-cut melon quality, but often reaches 10°C during transportation and in retail outlets. A comparison amongst 0, 5 and 10°C storage temperatures for fresh-cut melon over 14days reveals that storage at 0°C is optimal for avoiding increases in microbial load and loss of vitamin C especially at later time points. However, higher temperatures maintain better the balance of esters (acetate versus non-acetate) and phenolic content. The whole volatile organic compound (VOC) profile can be used to discriminate both time and temperature effects especially at earlier time points. Potential VOC markers for changes in vitamin C from day 0 to day 6 of storage (3-methyl butane nitrile) and temperature (limonene) are identified through a multi-trait analysis.
- Otimização da aplicação de um bio-estimulante para o aumento da produtividade e qualidade do morangoPublication . Silva, João F.; Pinheiro, Rita F.; Amaro, Ana L.; Pereira, Maria J.; Roriz, Mariana; Aguiar, Ana; Pintado, Manuela; Vasconcelos, Marta W.; Carvalho, Susana M. P.Biostimulants derived from natural products are being used by several strawberry growers to increase productivity and fruit quality. Given their high cost it is of utmost importance to carry out studies to validate their positive effect at plant level and to optimize their application. This study aimed at evaluating the effect of a commercial seaweed-derived biostimulant on yield and quality of strawberry produced in soilless cultivation system. Therefore, two application methods (fertigation and foliar application), two frequencies of application (every 15 and every 30 days throughout the cultivation period) and three doses of biostimulant (1.5, 3.0 and 4.5 l/ha) have been tested. In general, the application of biostimulant aiming at increased productivity proved to be more effective via fertigation compared to foliar application. The highest productivity was observed upon application of 4.5 l/ha every 15 days via fertigation (20% increase), with an increase in the total number of fruits produced (11%) and in the average fruit fresh weight (8%), compared to the commercial control (i.e. 1.5 l/ha every 30 days). As regards the quality parameters, there was a maximum increase of firmness (45%) when 4.5 l/ha of seaweed extract was applied via fertigation every 30 days. Foliar applications promoted the highest levels of soluble solids content and were efficient in maintaining the fruit brightness during storage. This study clearly showed that the method, dose and frequency of biostimulant application has a significant impact on the productivity and fruit texture.
- Production of aroma-rich extracts from sardine cooking wastewaters: exploring their potential for modulating feed intake in European seabassPublication . Resende, Daniela; Pereira, Maria J.; Sá, Tiago; Brazinha, Carla; Pintado, Manuela; Valente, Luisa M. P.; Velasco, CristinaManaging the canning industry’s nutrient-rich and odorous liquid waste is a hurdle. Concurrently, the growing use of vegetable ingredients in aquafeeds diminishes palatability and feed consumption in carnivorous fish. Thus, we hypothesized that aromas could be extracted from cooking wastewaters at canning factories and added to plant-based diets to stimulate intake in European seabass. Sardine cooking wastewaters were collected and tested directly (CW-A) or after vacuum distillation (VD-A) or liquid/liquid extraction with soybean oil (LLE-A). Despite losses in aldehydes and short-chain alcohols, both processes were effective in removing off-flavours. VD-A displayed a higher concentration of most aromas compared to LLE-A. Extracts were included at 2 μg g−1 of 1-penten-3-ol, the most abundant compound in all extracts, in diets (CW, VD, LLE). A non-supplemented diet was used as control. Each diet was assigned to six groups of juvenile fish, fed a single meal until apparent satiation. Our emphasis was on this initial feeding to comprehend the hedonic control of feed intake, minimizing habituation effects and the impact of the long-term metabolic requirements. Feed intake was highest for the control group. No differences on plasma metabolites were observed, suggesting feed intake was primarily regulated by hedonic rather than homeostatic mechanisms. Moreover, the lower intake in the supplemented diets was partially associated with a lower expression of orexigenic (intake-promoting) neuropeptides and higher expression of anorexigenic (intake-reducing) neuropeptides in the brain, despite the lack of significant diet-related differences. Overall, this study presents a novel approach to valorise cooking wastewater from the canning industry, since cooking wastewaters extracts rich in aromas were successfully produced, however, in the tested concentration, had no positive impact on the short-term feed intake response of European seabass.
- Repurposing sardine cooking wastewaters as ingredients for European seabass dietsPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.