1,721,071 research outputs found
Mechanical separation process for the value enhancement of Atlantic horse mackerel (Trachurus trachurus), a discard fish
Full text linkMechanically separated meat (MSM) is the product obtained by removing meat from bones by pressure application. Whole fillets and fish burgers from minced muscle and from mechanical separation of Atlantic horse mackerel (Trachurus trachurus) were evaluated immediately after processing (T0) and after 90 days of storage at − 20 °C for parameters related to quality loss. Firstly, mechanical separation inhibited water losses (2.67% against 4.57 and 5.57% in whole fillets and burgers from minced muscle, respectively), but the colour of MSM was duller and redder than the samples from other groups. Horse mackerel contained low fat (< 1 g/100 g muscle), and high PUFAω3 content (around 57 g/100 g total fatty acids), especially EPA and DHA (around 52 g/100 g) regardless the treatment. However, the species was susceptible to oxidation, as revealed by the high TBARS content at T0 (> 8 mg MDA-eq/100 g muscle). Nevertheless, Atlantic horse mackerel showed a high antioxidant capacity (ABTS, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid, DPPH, 2,2-diphenyl-1-picrylhydrazyl, and FRAP, ferric-reducing ability) at T0 which may protect muscle against oxidative damages both during processing treatment and storage. Industrial relevance The mechanical separation process described in the article has been largely utilized for terrestrial animal products. However, it is seldom adopted by fish industry, especially for recovering discard fish species. Horse mackerel is an underutilized species, normally transformed into animal feed despite its high levels of omega-3 polyunsaturated fatty acids. Therefore this study was conducted in order to determine the effect of a mechanical separation technique on the physicochemical properties of horse mackerel. Our study showed that, although this species is susceptible to oxidative changes, mechanically separate meat can be a high-quality ingredient in burgers, nuggets, sticks, or even sauces which may represent a way for the valorisation of discard species
Ginger (Zingiber officinale Roscoe) powder as dietary supplementation in rabbit: life performances, carcass characteristics and meat quality
Full text linkThe aim of this study was to evaluate the effect of dietary Zingiber officinale Roscoe (ginger) powder on rabbit productive performances, meat quality and shelf-life of raw and cooked meat. Ninety hybrid rabbits of 60 days old were fed three different diets: basal diet (control, C), basal diet supplemented by 4 g of ginger powder on 100 g of feed (G4) and basal diet supplemented by 8 g of ginger powder on 100 g of feed (G8) (3.6 and 7.2 g/100 g of dry matter for G4 and G8, respectively). Live weight, average daily gain and feed intake were recorded. Ten rabbits of each group were slaughtered at 90 days of age and meat quality was assessed during seven days of storage at 4 °C. Live performance and slaughter traits did not show any significant differences. Dietary ginger powder induced modification in pH of raw samples and in colour indexes of both raw and cooked meat. Lipid oxidation of raw samples was delayed in time by ginger feed addition even if no modification was highlighted in antioxidant capacity. Ginger powder could be a potential supplementation in diet of rabbits for increasing meat shelf-life
Effect of mechanical separation process on lipid oxidation in European aquacultured sea bass, gilthead sea bream, and rainbow trout products
Full text linkMechanical separation systems are a good option to create new fish products and open new market, however studies on the effect on quality of mechanical treatment on species of interest for European aquaculture, such as European sea bass, gilthead sea bream, and rainbow trout are scarce. Thus in this research, the effect on colour, nutritional quality, and lipid stability was considered immediately after separation process and after 90 days of frozen storage. Results revealed that mechanical separation technique significantly affected colour and lipid stability of the three studied species. Increases in L* and secondary oxidation products were observed, together with a decrease of antioxidant capacity. Nutritional value instead was unaffected by treatment. Thus, mechanical separation process could represent a new way to better exploit species of interest for European aquaculture and acquire new market niches, but oxidative processes during the treatment have to be limited and kept under control
Effect of the incorporation of a fermented rooibos (Aspalathus linearis) extract in the manufacturing of rabbit meat patties on their physical, chemical, and sensory quality during refrigerated storage
Full text linkIn the present study, rabbit meat patties were formulated with increasing incorporation levels of a fermented rooibos extract (Aspalathus linearis; R): Control (C), R1, R2 and R3 (0, 0.5, 1, 2% w/w R inclusion, respectively). Meat patties were subjected to a 7-day refrigerated storage trial, simulating retail display conditions. At day 0, 1, 3 and 6 of storage, patties drip loss, pH, L*a*b* colour traits (raw patties) and peroxide value (cooked patties) were analysed; at days 0 and 6, total volatile basic nitrogen (raw patties), fatty acid profile and sensory traits (cooked patties) were analysed. Increasing R incorporation levels lowered pH values of rabbit meat patties and increased their redness and yellowness indexes compared to the C group (P < 0.0001). R-treated cooked patties were protected from lipid oxidation compared to C ones (P < 0.0001), and this status was maintained up to the end of the trial. R1 rabbit meat patties showed sensory traits comparable to the C group, whereas R2 and R3 treatments provided negative outcomes. Based on the above-mentioned findings, rooibos can be considered a promising natural additive in the manufacturing of rabbit meat patties, up to the 0.5% incorporation level
Can the inclusion of black soldier fly (Hermetia illucens) in diet affect the flesh quality/nutritional traits of rainbow trout (Oncorhynchus mykiss) after freezing and cooking?
Full text linkPhysical and chemical parameters of rainbow trout fillets were tested during 120 days of frozen storage and following cooking. The fillets were obtained from rainbow trout-fed diets where dietary fishmeal was substituted with Hermetia illucens meal at 0, 25 and 50% inclusion levels, corresponding to control (C), Hi25, and Hi50 diets. Variations in quality traits of fillets emerged after 30 days of frozen storage, however they remained almost unchanged for the other 90 days. Increasing levels of H. illucens did not affect pH, shear stress, colour and water holding capacity of fillets. Saturated fatty acids were highly present in Hi50 samples, the polyunsaturated and some monounsaturated ones were higher in C than Hi50, whereas Hi25 always assumed intermediate contents in raw and cooked samples. A medium substitution at the 25% seemed to be the most practical application of insect meal in order to not modify too much the fillets characteristics
Assessing environmental sustainability of substitute feeding formulas for gilthead seabream (Sparus aurata) using Life Cycle Assessment
Full text linkThe rise in fish and seafood consumption driven by aquaculture comes with its share of challenges and controversies, notably the need for expanded feed production. The use of fishmeal and fish oil to raise carnivorous fish has caused environmental problems, including ecosystem imbalance and habitat destruction, as well as ethical issues like fishing forage fish for feed instead of human consumption. Thus, the industry has been actively pursuing alternative feed ingredients to reduce reliance on fish-derived components. This progress in the aquaculture feed sector has made selecting the best feed solution complex across various fronts. This study aims to assess the environmental impacts of three feed formulations, each with different protein sources (poultry by-products, PMB, Tenebrio molitor larvae, TM, or Hermetia illucens larvae, HI), tailored for the gilthead seabream (Sparus aurata), a prized species in European aquaculture. The environmental sustainability of these alternatives was evaluated against benchmarks of fishmeal and fish oil-based feed. Employing a cradle-to-gate approach and a FU of 1 kg of product, the study utilized OpenLCA software supported by the Ecoinvent ® v3.7.1 database. The results focused on the production stages of each ingredient, including logistical and transportation aspects leading up to the final formulation. All alternatives to traditional feed demonstrated either comparable or superior environmental performance (i.e. - 66 % of PMB-f, -33 % of TM-f and - 29 % HI-f kgCO2 eq) with few exceptions for TM-f. This investigation highlighted how integrating innovative ingredients could positively impact the environmental footprint of aquafeed production chains. Furthermore, the main hotspots in the alternative feed formulas life cycles have been identified and viable alternatives for improvement have been proposed, such as selecting different input materials or enhancing energy efficiency. This assessment allows to guide the selection of more environmentally friendly feed formulations before their integration into aquaculture chain processes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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