Giant Squid (Dosidicus gigas) Meal in Chicken Diets to Enrich Meat with n-3 Fatty Acids.

The main marketed parts of squid are the mantle, the head with tentacles, and fins. However, when the whole squid does not meet quality standards for human consumption it can be used for broiler feed. The objective of the study was to include giant squid (Dosidicus gigas) meal (GSM) in broiler rations to increase the content of the n-3 fatty acids eicosapentaenoic (EPA), docosapentaenoic (DPA), and docosahexaenoic (DHA) in chicken meat. Two hundred Ross 380 chickens, half male, half female, and one day old, were randomly distributed in a 4x2x2 factorial arrangement. The factors were the treatment (0%, 1.67%, 3.34%, and 5.01% of GSM in the diet), sex, and content of n-3 in the legs with thighs and the breasts. Each treatment had five repetitions with 10 birds each. There were no differences (p > 0.05) in the production parameters for both sexes. The contents of EPA, DPA, and DHA increased in the females and in the legs with thighs (p < 0.05) with GSM. Acceptance for the flavor and texture of meat was higher in the treatment with 1.67% GSM than in the other treatments. It is concluded that GSM is an alternative for increasing the amount of n-3 in chicken meat.

The role of glycerol on the thermal gelation of myofibrillar protein from giant squid (Dosidicus gigas) mince.

This work studies the effect of glycerol on the chemical physics of the thermal gelatin of protein from giant squid minced meat. The presence of glycerol induced changes in the nano protein particles (NPP) self-assembled structures. These nanoscale events resulted in dramatic changes on the interactions between proteins when forming gels, with the contribution of ionic interactions increasing by 17% upon gelation, that of hydrogen bonds reducing by 50%, that of hydrophobic interactions decreasing by 45%, and that of disulphide bonding increasing by 18%. Glycerol also induced cluster formation in myofibrillar solutions. As a result, incorporation of glycerol increased springiness, resilience, and adhesiveness of the formed gels by 13%, 25%, and 370% respectively. The heating gelation of myofibrillar proteins was monitored at various temperatures via recording the elastic and storage moduli. Rheology and micro-rheology studies revealed that the presence of glycerol increased G' and G″ of thermally-gelled giant squid meat.

A Collagen Basketweave from the Giant Squid Mantle as a Robust Scaffold for Tissue Engineering.

The growing applications of tissue engineering technologies warrant the search and development of biocompatible materials with an appropriate strength and elastic moduli. Here, we have extensively studied a collagenous membrane (GSCM) separated from the mantle of the Giant squid Dosidicus Gigas in order to test its potential applicability in regenerative medicine. To establish the composition and structure of the studied material, we analyzed the GSCM by a variety of techniques, including amino acid analysis, SDS-PAGE, and FTIR. It has been shown that collagen is a main component of the GSCM. The morphology study by different microscopic techniques from nano- to microscale revealed a peculiar packing of collagen fibers forming laminae oriented at 60-90 degrees in respect to each other, which, in turn, formed layers with the thickness of several microns (a basketweave motif). The macro- and micromechanical studies showed high values of the Young's modulus and tensile strength. No significant cytotoxicity of the studied material was found by the cytotoxicity assay. Thus, the GSCM consists of a reinforced collagen network, has high mechanical characteristics, and is non-toxic, which makes it a good candidate for the creation of a scaffold material for tissue engineering.

Assessments of metallic contents in rare cephalopods from the Canary Islands: relationships with depth habitat and body size.

This study investigated 20 elements in the muscle of 11 cephalopod species caught in the Canary Islands inhabiting from coastal to meso-bathypelagic habitats. Among them, trace element contents from large and elusive cephalopods such as Architeuthis dux, Taningia danae, Lepidoteuthis grimaldii, and Haliphron atlanticus were determined. Statistically significant differences in element concentration were found among class sizes and habitat. Large species that are inhabiting in deepest waters such as Loligo forbesii, A. dux, T. danae, H. atlanticus, and L. grimaldii showed a high load and variability in Fe and Al, while coastal species were characterized by a homogeneous element composition, being the Zn loads highest than other elements. Metal contents in large and elusive cephalopod species were dominated by Fe, Ni, Al, Zn, and Sr, with these species being able to carry important amounts of these elements to predators such as deep-diving odontocetes that reside around the Canary waters.

Utilization of Marine Waste to Obtain ß-Chitin Nanofibers and Films from Giant Humboldt Squid Dosidicus gigas.

ß-chitin was isolated from marine waste, giant Humboldt squid Dosidicus gigas, and further converted to nanofibers by use of a collider machine under acidic conditions (pH 3). The FTIR, TGA, and NMR analysis confirmed the efficient extraction of ß-chitin. The SEM, TEM, and XRD characterization results verified that ß-chitin crystalline structure were maintained after mechanical treatment. The mean particle size of ß-chitin nanofibers was in the range between 10 and 15 nm, according to the TEM analysis. In addition, the ß-chitin nanofibers were converted into films by the simple solvent-casting and drying process at 60 °C. The obtained films had high lightness, which was evidenced by the CIELAB color test. Moreover, the films showed the medium swelling degree (250-290%) in aqueous solutions of different pH and good mechanical resistance in the range between 4 and 17 MPa, depending on film thickness. The results obtained in this work show that marine waste can be efficiently converted to biomaterial by use of mild extractive conditions and simple mechanical treatment, offering great potential for the future development of sustainable multifunctional materials for various industrial applications such as food packaging, agriculture, and/or wound dressing.

An encounter between a pelagic shark and giant cephalopod.

An oceanic whitetip shark (Carcharhinus longimanus) was observed off the coast of Kona, Hawaii, with scars caused by the tentacles of a large cephalopod. While the exact species could not be confirmed, candidate species include the giant squid (Architeuthis dux) or species from the genera Thysanoteuthis (flying squids) and Megalocranchia (glass squids). Telemetry shows C. longimanus will dive within the mesopelagic zone and may interact with or even forage for large cephalopods.

Effect of autoclaving on the mechanical properties and structure of the giant squid hydrolysate-polysaccharide gel.

Fish hydrolysates are an attractive option for preparing composite gel foods. However, not much is known regarding their gel properties. Here, we investigated the effect of the autoclaving treatment (121°C, 10 min) on the microstructure and properties of the giant squid hydrolysate-konjac glucomannan-κ-carrageenan-locust bean gum gel (GSH-P gel). The nuclear magnetic resonance proton spin-spin relaxation time (T2 ) measurements indicated that autoclaving led to stronger water-binding ability of the GSH-P gel. The rheological measurements indicated that autoclaving led to significantly higher viscoelastic modulus and gel strength. The results of confocal laser scanning microscopy and small-angle X-ray scattering indicated that the phase separation of polysaccharides and proteins/peptides was enhanced by autoclaving, and the polysaccharides swelled better, resulting in less, but ordered, network structures. Autoclaving had a similar, but insignificant, positive effect on the polysaccharide (P) gel. Thus, GSH seems to play an important role in the process of polysaccharide gelation. This study shows that autoclaving can alter the structure and improve the properties of the GSH-P gel.

Composición química de harina de calamar gigante dosidicus gigas / Chemical composition of giant squid dosidicus gigas meal

El potencial de uso de la harina de calamar gigante (Dosidicus gigas) (HCG). como alternativa en el desarrollo de productos con valor agregado es relevante. Sin embargo hace falta conocer los elementos químicos que la conforman. El objetivo de este trabajo fue determinar la composición química de la harina de calamar gigante (Dosidicus gigas) procedente de Guaymas, Sonora, México y su posible alternativa para el desarrollo de alimentos funcionales. Los resultados indicaron un alto contenido de proteína (77,7%), sobresaliendo lisina y ácido glutámico (10,16 y 14,53 g aa/100g proteína respectivamente), aminoácidos azufrados y aminoácidos hidrofóbicos. El contenido de la fracción grasa (6,3%) fue bajo así como el de fibra cruda (2,7%), reportada como quitina, reflejándose en el bajo aporte calórico (4 kcal/g). La relación entre ácidos grasos saturados, monoinsaturados y poliinsaturados fue de 1,66:1:1,08 y de n6:n3 fue de 1:1,35. Se concluye que HCG es un ingrediente con posibilidades de uso en panificación, galletas saladas, sazonadores, aderezos, a los que les podría dar un valor agregado. Sin embargo el factor limitante para su uso está en el olor y sabor a pescado, por lo que su aplicación se sugiere dirigir la aplicación hacia el desarrollo de nuevos productos vinculados con preparaciones típicas que incluyan pescados y derivados(AU)

The potential use of giant squid (Dosidicus gigas) meal (GSM) as an alternative in the development of value-added foods may be relevant. However one must know the chemical elements that constitute it. The aim of this study was to determine the chemical composition of giant squid Dosidicus gigas meal from Guaymas, Sonora, Mexico and its possible alternative for the development of functional foods. The data indicated a high protein content (77,7%), lysine and glutamic acid (10,16 and 14,53 g aa/100g protein respectively), sulfur amino acids and hydrophobic amino acids. The content of fat fraction (6,3%) was low and crude fiber (2,7%) reported as chitin, reflected in the low calorie (4 kcal/g). The ratio of saturated, monounsaturated and polyunsaturated fatty acids was 1,66: 1: 1,08 and n6: n3 was 1: 1,35. It is concluded that GSM is an ingredient with potential for use in bread, crackers, seasonings, dressings, which could give them added value. However the limiting factor for use is in the smell and taste of fish, so that its application would be directed at the development of new products related with typical preparations that include fish and derivatives(AU)

The Kraken: when myth encounters science / O Kraken: quando mito e ciência se encontram

Hundreds of years ago, sailors were terrified by the Kraken, a dreadful sea monster capable of sinking ships and with a taste for human flesh. Today we know the legends of this monster were based on sightings of giant squids. This animal belongs to the genus Architeuthis and was the subject of many scientific studies. Despite its enormous size (up to 18m), the giant squid is astoundingly elusive and much of its biology remains unknown. Thus shrouded in mystery, Architeuthis is almost a mythological creature and has a place both in science and in myth: the very last of the legends to persist to this day.

Séculos atrás, marinheiros se amedrontavam com histórias do Kraken, um terrível monstro marinho capaz de afundar embarcações e devorar suas tripulações. Atualmente, sabemos que a lenda desse monstro foi baseada em encontros com lulas-gigantes. Esse animal pertence ao gênero Architeuthis e foi alvo de muitos estudos científicos. Apesar de seu enorme tamanho (pode chegar a 18m), a lula-gigante é incrivelmente elusiva e muito de sua biologia permanece desconhecida. Assim, envolto em mistério, Architeuthis é quase um ser mitológico, ocupando um lugar tanto na ciência como no mito: a última das lendas a persistir nos dias de hoje.

Production and functional evaluation of a protein concentrate from giant squid (Dosidicus gigas) by acid dissolution and isoelectric precipitation.

A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle.