Fishery residues are abundant raw materials that also provide numerous metabolites with high added value. Their classic valorization includes energy recovery, composting, animal feed, and direct deposits in landfills or oceans along with the environmental impacts that this entails. However, through extraction processes, they can be transformed into new compounds with high added value, offering a more sustainable solution. The aim of this study was to optimize the extraction process of chitosan and fish gelatin from fishery waste and their revalorization as active biopolymers. We successfully optimized the chitosan extraction process, achieving a yield of 20.45% and a deacetylation degree of 69.25%. For the fish gelatin extraction process, yields of 11.82% for the skin and 2.31% for the bone residues were achieved. In addition, it was demonstrated that simple purification steps using activated carbon improve the gelatin’s quality significantly. Finally, biopolymers based on fish gelatin and chitosan showed excellent bactericidal capabilities against Escherichia coli and Listeria innocua. For this reason, these active biopolymers can stop or decrease bacterial growth in their potential food packaging applications. In view of the low technological transfer and the lack of information about the revalorization of fishery waste, this work offers extraction conditions with good yields that can be easily implemented in the existing industrial fabric, reducing costs and supporting the economic development of the fish processing sector and the creation of value from its waste.

The replacement of soybean meal with sweet white lupin (Lupinus albus L.) seeds was investigated in the diets of Iberian pigs during the growing and fattening phases, evaluating its effects on growth performance, carcass traits, and meat quality. Iberian pigs (n = 50) were divided into two dietary groups (n = 25 per group), receiving either a lupin-based concentrate or a soybean meal-based concentrate. The data were analysed using one-way analysis of variance (ANOVA), with a significance level of p < 0.05. The results showed that lupin substitution had no adverse effect on body weight, average daily gain, or carcass characteristics. No significant differences were observed in meat quality parameters such as pH, colour, and texture. However, significantly (p = 0.007) lower levels of saturated fatty acids (SFA) content were found in the intramuscular fat of pre-finishing (primor) pigs fed lupin-based diets. In addition, these pigs had lower plasma triglyceride levels at the end of the growing phase. Overall, the results suggest that sweet white lupin is a viable alternative protein source in Iberian pig production, offering potential health benefits in line with consumer preferences for sustainably produced, healthier meat products, without compromising production efficiency or product quality.

This paper attempts to analyse lamb burgers from meat cuts of lower commercial value to which various amounts of freeze-dried pecan nuts (5%, 10% and 15%) were added to study the influence of the addition of pecans on the quality of the burger. One hundred eight burgers were evaluated by means of physicochemical, sensory and microbiological analyses. The addition of pecan nuts mainly affected the meat’s fatty acid profile. Fat content was higher as the amount of pecan nuts was increased, and the monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels also increased (p < 0.001), whereas the saturated fatty acid content decreased (p < 0.001). Pecan nuts also proved able to increase the antioxidant capacity of the product, significantly reducing the oxidation values of lipids (p < 0.001) and proteins (p < 0.05). In general, no significant differences were identified in the sensory attributes under study. In conclusion, we found that the use of pecan nuts improves the nutritional content of the hamburgers without negatively affecting the technological or sensory properties.

This paper describes for the first time a case of avian ringworm, caused by Cutaneotrichosporon jirovecii in a small flock of Extreme?a blue hens and highlights that the disease could occur in outbreak proportions, with 46.70% of cocks affected. Infected birds had white crusts on the comb, and most affected animals showed white or light brown nodules that were loosely attached to the tip of feathers, but no systemic disease signs were observed. The diagnosis of Trichosporon jirovecii was made by morphological identification, and it was confirmed by sequencing amplification product of the PCR using universal primers of the internal transcribed spacer region.

El objetivo de este estudio es determinar si la incorporación del subproducto orujo de uva tinta (variedad 'Tempranillo') en la dieta de corderos de cebo, reduce las emisiones de metano, y si esta modificación repercute en los parámetros productivos y calidad del producto final. Para ello, se emplearon 12 corderos merinos, separados en dos lotes; Control (concentrado de cebo convencional) y Experimental (sustitución 5% de cebada del concentrado por 5% orujo de uva tinta). Se determinó diariamente la concentración de metano mediante detector láser metano portátil. Se llevó a cabo un control del consumo y peso de los animales, analizando finalmente el color, pH, humedad, oxidación lipídica, grasa intramuscular y perfil ácidos grasos del longissimus dorsi. Los resultados de este estudio preliminar mostraron una reducción de la concentración media de metano durante la eructación (27,77ppm.m vs. 52,30ppm.m) en el lote experimental, una menor frecuencia de eructación en este lote frente al control, y además, también se pudo observar una reducción de la concentración máxima de metano emitida durante la respiración y eructación (54,15ppm.m vs. 101ppm.m). Por su parte, los índices productivos, al igual que los parámetros de calidad de carne no se vieron alterados por la modificación en la dieta. Por tanto, la incorporación de orujo de uva tinta al 5% en el concentrado de cebo de corderos podría tener un efecto positivo sobre el impacto medioambiental, sin otras repercusiones negativas, sin embargo, es necesario ampliar el periodo de estudio, así como el número de animales para llegar a unas conclusiones más robustas.