Effects of gelatin origin, bovine-hide and tuna-skin, on the properties of compound gelatin-chitosan films

With the purpose to improve the physico-chemical performance of plain gelatin and chitosan films, compound gelatin-chitosan films were prepared. The effect of the gelatin origin (commercial bovine-hide gelatin and laboratory-made tuna-skin gelatin) on the physico-chemical properties of films was studied. The dynamic viscoelastic properties (elastic modulus G', viscous modulus, G″ and phase angle) of the film-forming solutions upon cooling and subsequent heating revealed that the interactions between gelatin and chitosan were stronger in the blends made with tuna-skin gelatin than in the blends made with bovine-hide gelatin. As a result, the fish gelatin-chitosan films were more water resistant (∼18% water solubility for tuna vs 30% for bovine) and more deformable (∼68% breaking deformation for tuna vs 11% for bovine) than the bovine gelatin-chitosan films. The breaking strength of gelatin-chitosan films, whatever the gelatin origin, was higher than that of plain gelatin films. Bovine gelatin-chitosan films showed a significant lower water vapour permeability (WVP) than the corresponding plain films, whereas tuna gelatin-chitosan ones were only significantly less permeable than plain chitosan film. Complex gelatin-chitosan films behaved at room temperature as rubbery semicrystalline materials. In spite of gelatin-chitosan interactions, all the chitosan-containing films exhibited antimicrobial activity against Staphylococcus aureus, a relevant food poisoning. Mixing gelatin and chitosan may be a means to improve the physico-chemical performance of gelatin and chitosan plain films, especially when using fish gelatin, without altering the antimicrobial properties. © 2011 Elsevier Ltd.Peer Reviewe

Characterization of glucose-crosslinked gelatin films reinforced with chitin nanowhiskers for active packaging development

To find renewable and sustainable alternatives to reduce the severe environmental impact of single-use synthetic plastic packaging, glucose-crosslinked gelatin films containing different amounts of chitin nanowhiskers (CNWs) were prepared. CNWs were first prepared by acid hydrolysis of chitin from shrimps, and characterized (morphological and thermal properties), before their addition into film-forming formulations. The films were heat-treated to promote the chemical crosslinking Maillard reaction (MR), between glucose and gelatin. The films then became less soluble (from 100% to ∼10%), thermally more stable, had a notably improved UV–vis light absorption capacity, and presented significantly enhanced tensile strength (from 42 to 77 MPa) and Young's modulus (from 1476 to 2921 MPa), however, they also became less flexible (from 17% to 7%) and transparent. These property alterations were mainly related to changes in crystallinity, the MR and to a lesser extent, to the formation of noncovalent (electrostatic and hydrogen bonding) interactions between CNWs and gelatin. Furthermore, due to the formation of MR products, the films turned yellow/dark brown and released antioxidant compounds (inhibition ∼33%) while immersed in water, which gave the films their active properties (stabilization of free radicals). These films have considerable potential as reinforced active packaging films for renewable food packaging applications.The authors would like to thank the Ministry of Business, Innovation and Employment of New Zealand (MBIE, Biocide Toolbox programme) and the Spanish Ministry of Science and Innovation (projects PID2019-108361RB-I00 and AGL2017-84161-C2-1-R) for funding. A.E. thanks the State Research Agency of Spain within the Juan de la Cierva - Incorporation action (IJC2019-039697I)

Potential antihypertensive effect of protein by-products from whitefish filleting after simulated gastrointestinal digestion

publishedVersio

Clubs de lectura como estrategia para aumentar el conocimiento sobre nutrición entre la población general: Estudio piloto

Introduction: The spread of false news related to nutrition shows the need to provide general public validated information on food and health, inducing them to follow healthy dietary habits. Objective: To assess whether attendance to book clubs devoted to scientific disseminations books is a useful strategy for improving nutritional knowledge among the population. Methodology: 65 adults participated in a reading club, attending a research center once a month for 4 months to talk about informative scientific books on food/nutrition. The knowledge of the participants was monitored through a survey performed in all the sessions of the club. Results: Participants were mostly female with university studies. Attendance to the book clubs caused a significant increase (P < 0.05) in the number of correct answers on a questionnaire about common misbeliefs on the topics covered in the discussed books. Participants showed a high degree of satisfaction with the activity and willingness to read more scientific dissemination books, even when most of them were not previously usual readers. Conclusions: Book clubs based on popular science books and led by scientists with expertise in the field could increase nutritional knowledge among general population, which should be further explored in different socioeconomic contexts.Introducción: La difusión de noticias falsas relacionadas con la nutrición muestra la necesidad de proporcionar al público general información validada sobre alimentación y salud, induciendo a llevar hábitos dietéticos saludables. Objetivo: Evaluar si la asistencia a clubs de lectura dedicados a libros de divulgación científica es una estrategia útil para mejorar el conocimiento nutricional entre la población. Metodología: 65 adultos participaron en un club de lectura, asistiendo una vez al mes, durante 4 meses a un centro de investigación para conversar sobre libros científicos divulgativos de alimentación/nutrición. Se llevó a cabo un seguimiento de los conocimientos de los participantes a través de una encuesta realizada en todas las sesiones del club de lectura. Resultados: Los participantes fueron en su mayoría mujeres con estudios universitarios. La asistencia a los clubs de lectura provocó un aumento significativo (P < 0,05) en el número de respuestas correctas en un cuestionario sobre las creencias erróneas comunes en los temas tratados en los libros discutidos. Conclusiones: Los clubs de lectura basados en libros de divulgación científica y dirigidos por científicos con experiencia en el campo pueden aumentar el conocimiento nutricional entre la población en general, debiéndose explorar más a fondo en diferentes contextos socioeconómicos

Active antioxidant gelatin films composed by coffee parchment lignin nanoparticles

Trabajo presentado a la 36th EFFoST International Conference will be held in Dublin, Ireland from 7-9 November 2022.Peer reviewe

Recent advances in astaxanthin micro/nanoencapsulation to improve its stability and functionality as a food ingredient

This article belongs to the Special Issue Astaxanthin: A Potential Therapeutic Agent.Astaxanthin is a carotenoid produced by different organisms and microorganisms such as microalgae, bacteria, yeasts, protists, and plants, and it is also accumulated in aquatic animals such as fish and crustaceans. Astaxanthin and astaxanthin-containing lipid extracts obtained from these sources present an intense red color and a remarkable antioxidant activity, providing great potential to be employed as food ingredients with both technological and bioactive functions. However, their use is hindered by: their instability in the presence of high temperatures, acidic pH, oxygen or light; their low water solubility, bioaccessibility and bioavailability; their intense odor/flavor. The present paper reviews recent advances in the micro/nanoencapsulation of astaxanthin and astaxanthin-containing lipid extracts, developed to improve their stability, bioactivity and technological functionality for use as food ingredients. The use of diverse micro/nanoencapsulation techniques using wall materials of a different nature to improve water solubility and dispersibility in foods, masking undesirable odor and flavor, is firstly discussed, followed by a discussion of the importance of the encapsulation to retard astaxanthin release, protecting it from degradation in the gastrointestinal tract. The nanoencapsulation of astaxanthin to improve its bioaccessibility, bioavailability and bioactivity is further reviewed. Finally, the main limitations and future trends on the topic are discussed

Tendencias en el desarrollo de análogos cárnicos sostenibles

Se estima que en el año 2050 la población mundial ascienda a más de 9.000 millones de personas, con un incremento de la demanda de alimentos de origen animal de entre un 70-80% (Oonincx y de Boer, 2012). Esta demanda es debida no solamente a la mayor población, sino también al incremento del nivel de renta, pues se ha observado que el mayor desarrollo conlleva la adopción de dietas más occidentalizadas (Turk, 2016).Este estudio ha sido financiado por los proyectos AGL-2014-53207-C2-R y S2013/ABI-2913 (MEDGAN-CM).Peer reviewe

Functional aptitude of hake minces with added TMAO-demethylase inhibitors during frozen storage

The ability of compounds of natural origin (black, white, red, and green tea extracts, phytic acid) to inhibit TMAO-demethylase enzyme was assayed. Black tea and phytic acid exerted the highest inhibiting activities, similar to the already known inhibitor sodium citrate. Hake minces incorporating these three compounds were prepared and stored frozen (150 days, –12 °C). TMAO-demethylase enzyme was partially inhibited (lower enzyme activity, reduction of formaldehyde accumulation). The study of physicochemical properties of the minces (salt-soluble proteins, water holding capacity, structural water associated with myofibrils) pointed to evident protein aggregation and loss of functionality when phytic acid was added, whereas black tea and sodium citrate did not have a negative effect. Consequently, the salt-ground mince with phytic acid showed worse viscoelastic properties than the others. In conclusion, black tea polyphenols and sodium citrate can be used as additives to inhibit TMAO-demethylase enzyme during frozen storage of fish minces.The authors wish to thank the European Commission for financial support under the FEDER-INTERCONNECTA program (project reference PROPESCA-ITC-20151199).Peer reviewe

Physical and chemical properties of tuna-skin and bovine-hide gelatin films with added aqueous oregano and rosemary extracts

The properties of edible, gelatin-based films with added oregano or rosemary extract (two different concentrations) were studied. Gelatins from different sources (bovine-hides and tuna-skins) were employed with a view to elucidating how inherent gelatin characteristics may affect interaction of the gelatin with the polyphenols in the added extract and hence the properties of the resulting films. The bovine-hide gelatin reacted only slightly with the polyphenols in the extracts as shown by the electrophoretic profile and analysis of the dynamic viscoelastic properties, and consequently the attributes (mechanical properties, water solubility, water vapour permeability) of the films were practically unchanged compared with the film made without any added plant extract. The tuna-skin gelatin did evidence some interactions with the polyphenols in both the oregano and the rosemary extracts, especially for the more concentrated of the two extracts tested, thereby altering the attributes of the corresponding films, namely, a higher glass transition temperature, decreased deformability, and, in particular, increased water solubility. Opacity increased irrespective of gelatin origin and plant extract type and concentration. © 2008 Elsevier Ltd. All rights reserved.Peer Reviewe

Shrimp (Litopenaeus vannamei) muscle proteins as source to develop edible films

Edible films were successfully obtained from shrimp (Litopenaeus vannamei) muscle protein plasticized with glycerol. The effects of pH, thermal treatment, and the addition of a natural cross-linker (cinnamaldehyde) to the film-forming solution on the properties of the resulting films were evaluated. The pH was found to be a key parameter that greatly influenced the properties of the films, those produced at pH 2 showing higher mechanical properties, water resistance, transparency, and UV barrier properties than those produced at pH 11. Extensive proteolysis and lower protein cross-linking were evidenced in pH 11 films, as determined by SDS-PAGE and infrared spectroscopy (ATR-FTIR). The application of thermal treatment (80°C/15min) gave rise to considerable protein cross-linking, resulting in an improvement in mechanical properties, water resistance, and transparency of films produced at pH 11. The treatment with 5g of cinnamaldehyde/100g protein at pH 2 produced the film with the best physicochemical properties. Films produced at pH 2 with or without cinnamaldehyde had antimicrobial effects on fish spoilage bacteria, and the one containing cinnamaldehyde was stable after 30 days of storage at 17°C and 58% relative humidity. © 2014 Elsevier Ltd.The authors wish to thank the Spanish Ministry of Economy and Competitiveness for financial support through project AGL2011-27607Peer Reviewe