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- Effect of melatonin implants on carcass characteristics and meat quality of slow-growing chickensPublication . Nieto, Jaime; Leite, Ana; Vasconcelos, Lia; Plaza, Javier; Abecia, José-Alfonso; Revilla, Isabel; Palacios, Carlos; Teixeira, AlfredoThis study evaluated the effect of melatonin implants on carcass characteristics and meat quality of slow-growing broilers slaughtered at 43 and 97 days (d) of age. A total of 128 one day-old male broilers (Coloryeld) were randomly divided into two groups, which in turn were divided into 8 groups (replicates) of 8 broilers each one. One group (64 animals) was the control group (C) and the other received a melatonin implant (18 mg melatonin per animal) at 8 d of age (M). The animals were reared for 97 d. For the first 42 d they were kept in an enclosed facility and then allowed access to the outside. Two culls were performed: one at 43 d and one at 97 d, randomly selecting 8 chicks from each group at each time (N = 8 × 2 × 2= 32). Carcass traits and meat quality were evaluated on these samples. Chickens slaughtered at older ages had higher dead-plucked, leg and carcass weights (P < 0.05). In terms of meat quality, chickens slaughtered at 97 days had higher L* (P < 0.001), lower a*, b* and chroma values (P < 0.01), as well as lower pH (P = 0.006), higher shear strength (P < 0.001), water holding capacity (P < 0.001) and water activity (P = 0.036). The melatonin implants did not influence carcass characteristics (P>0.05). Luminosity, tone and water activity decreased with melatonin implants at 43 d of age (P <0.001), whereas pH increased (P = 0.004). At 97 d after slaughter, meat yellowness was lower (P = 0.028) and firmness increased (P = 0.029). At both time points, melatonin caused reddening of the meat (P < 0.001). Lipid oxidisability tended to be reduced, extending the shelf life of the meat (P = 0.068). The fatty acid profile was little affected by the placement of the implants. Age and melatonin have different effects on the meat quality of slow-growing chickens. While age affects several factors such as texture and fatty acid profile, melatonin improves colour, water activity and lipid oxidation. Its use could improve preservation and extend the shelf life of meat
- Exploring the Potential of Olive By-Products in Bísaro Pig Feed: Effects on the Chemical Compositions and Fatty Acid Profiles of Three Different MusclesPublication . Paié-Ribeiro, Jessica; Pinheiro, Victor; Guedes, Cristina; Gomes, Maria José; Teixeira, José; Leite, Ana; Vasconcelos, Lia; Teixeira, Alfredo; Outor-Monteiro, DivanildoThe olive oil industry generates large quantities of olive cake (OC), making its use in animal feed an environmentally sustainable alternative. Considering that the ham of Bísaro pigs is traditionally used for the production of cured ham, the analysis of raw meat is essential to understand how diet influences its quality before the maturation process. This study examined the effect of different types of OC in the diets of Bísaro pigs, focusing on the chemical compositions and fatty acid profiles of three fresh ham muscles—biceps femoris (BF), semimembranosus (SM), and semitendinosus (ST). Forty Bísaro pigs were assigned to five diets: control (CD), 10% raw OC (COC), two-phase OC (TPOC), exhausted OC (EOC), and exhausted OC with 1% olive oil (EOC-OO). The diets significantly influenced moisture, protein, collagen, and haem pigments (p < 0.05). TPOC had the highest moisture content, while CD had the lowest. Protein levels were higher in BF and SM for OC-fed pigs. Collagen in ST was highest in CD and lowest in EOC. Haem pigments varied, with EOC highest in BF and ST and EOC-OO highest in SM. Significant MUFA differences were found in BF (p < 0.001), highest in CD and lowest in TPOC. PUFA levels and the PUFA/SFA ratio were highest in TPOC (p < 0.001), while SFA remained unchanged. The results suggest that up to 10% OC can be included in pig diets without compromising meat quality, but factors such as economic viability and nutritional variability must be considered. This study provides new insights into how OC affects muscle composition, contributing to optimizing feeding strategies for better meat quality and sustainability.
- Escalonamentos de tratamentos em unidades de saúdePublication . Leite, Ana; Pereira, Ana I.; Fernandes, AdíliaO problema de escalonamento de tratamentos em unidades de saúde é um tema atual na investigação operacional e bastante importante na área da gestão hospitalar, estando associado à redução de custos com o pessoal especializado bem como a redução de tempo de espera dos utentes.
- Alheiras with animal fat replacement: application of a gelled emulsion based on hemp oil (Cannabis sativa L.) and buckwheatPublication . Botella-Martinez, Carmen; Fernandez-Lopez, Juana; Ferreira, Iasmin da Silva; Leite, Ana; Vasconcelos, Lia; Dominguez, Rubén; Perez-Alvarez, José Angel; Teixeira, Alfredo; Viuda-Martos, ManuelA gelled emulsion elaborated using hemp seed oil and buckwheat flour was utilized as pork backfat substitute in a typical Portuguese meat product named Alheira. Three different formulations were prepared: Alheiras control (AC) with a fat content of 13%, alheiras where the 25% pork backfat was substituted with a hemp seed oil-GE (AH25), and alheiras where the 50% pork backfat was substituted with a hemp seed oil-GE (AH50). The chemical composition as well as the physicochemical properties and lipid stability of different samples were assessed. Reformulated samples showed similar protein, moisture, and fat content (p < 0.05) that AC. However, AH25 and AH50 had a higher amount of linoleic acid (16.29 and 22.14 g/100 g, respectively) and linolenic acid (1.75 and 3.45 g/100 g, respectively) than AC (12.71 and 0.51 g/100 g). Similarly, AH25 and AH50 showed lower saturated fatty acids (35.28 and 30.37 g/100 g, respectively) than AC (37.37 g/100 g). The substitution of pork backfat for hemp seed oil-GE did not modify significantly the physicochemical properties of samples. On the other hand, the lipid oxidation values increased by 30 and 65% in AH25 and AH50 respectively, in comparison to AC due to the use of polyunsaturated oils, which are highly susceptible to oxidation. This work established that the use of gelled emulsions elaborated using hemp oil and buckwheat flour may be a promising strategy to obtain meat products with a better healthier profile.
- Can the inclusion of different olive oil cakes on diet affect carcass quality of Bísaro?Publication . Leite, Ana; Ferreira, Iasmin da Silva; Vasconcelos, Lia; Domínguez, Rubén; Rodrigues, Sandra; Outor-Monteiro, Divanildo; Pinheiro, Victor; Lorenzo, José M.; Teixeira, AlfredoThe present work aimed to evaluate the potential incorporation of olive by-products olive cake (crude olive cake, exhausted olive cake without and with olive oil and two-phase olive cake) in the diet of Bísaro pigs, a local breed reared in Trás-os-Montes region (northeast of Portugal) and to study its effect on the animal´s growth traits and carcass characteristics. The experiment was carried out on 40 Bísaro pigs selected from animals delivered for slaughter to Bragança-Portugal. Five different treatments with different olive cakes (T1 – basal diet; T2 – 10% crude olive oil; T3 – 10% olive cake two phases, T4 – 10% exhausted olive cake; and T5 – 10% exhausted olive cake + 1% olive oil) were. Body weight, pH (1 and 24 hours after slaughter) and carcass weight were similar in all treatments and no significant differences were observed. No significant differences were found between the treatments for the carcass measurements performed, except for the longissimus dorsi length at seventh rib (P<0.05) varying between 75.9 (T3) and 87.3 (T5) mm and fat depth measured at the last rib (P3 measurement) varying between 91.1 (T5) and 99.2 (T4) (P<0.05). The data provide the definition of a standard carcass for the breed and this ratio of body weight. Results indicate that this oil by-product can be used to feeding Bísaro pigs.
- Exploring the Nexus of Feeding and Processing: Implications for Meat Quality and Sensory PerceptionPublication . Rodrigues, Sandra; Leite, Ana; Vasconcelos, Lia; Teixeira, AlfredoThe intrinsic quality of meat is directly related to muscle and fat tissues. Factors such as the rate and extent of anaerobic glycolysis affect muscle pH, influencing the meat’s color, water holding, and texture. Postmortem anomalies can result in deviations from this intrinsic quality. The animals’ diet plays a crucial role in meat quality. Specific nutrients, such as proteins, vitamins, and minerals, affect meat’s texture, flavor, and juiciness. Feeds rich in omega-3 fatty acids can improve the sensorial quality of meat. Meat processing and methods such as aging, marinating, and cooking affect the texture, flavor, and juiciness, which can be evaluated by specific equipment or trained or untrained consumers. This comprehensive review investigates the relationship between animal feeding practices and meat processing techniques and their combined impact on meat quality and sensory perception. By synthesizing recent research, we explore how various feeding protocols (including diet composition and feed additives) and processing methods shape meat products’ nutritional value, texture, flavor profile, and overall consumer appeal. Understanding this nexus is crucial for optimizing meat quality while ensuring sustainability and safety in the food supply chain.
- Chemical, physicochemical and sensorial characterization of nitrite-free dry-cured bísaro shouldersPublication . Leite, Ana; Vasconcelos, Lia; Ferreira, Iasmin da Silva; Sarmiento-García, Ainhoa; Domínguez, Rubén; Santos, Eva María; Campagnol, Paulo C.B.; Rodrigues, Sandra; Lorenzo, José M.; Teixeira, AlfredoThe aim of the current experiment was to characterize and evaluate the effect of the dry-curing process on chemical composition, physicochemical properties, and sensory characteristics of the dry-cured Bísaro shoulders. For this purpose, thirty-eight raw forelegs were used, and no nitrites were added during the dry-curing process. This process increased protein, fat, ash content, and pH, with a decrease in moisture and water activity (p < 0.001). The dry-cured shoulders were darker (L*), less red (a*), and less yellow (b*) than the raw shoulders (p < 0.001), and this may be mainly due to the moisture reduction. The proportion of polyunsaturated fatty acids (PUFA) decreased during processing, whereas the saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) increased (p < 0.001), which could be related with the oxidative degradation. The sensory analysis showed that dry-cured Bísaro shoulders presented similar organoleptic characteristics to other dry-cured meat products. Also, the chemical composition and fatty acid profile of the dry-cured Bísaro shoulder showed results comparable to those of other cured products. This study revealed that it is possible to obtain safer and healthier dry-cured Bísaro shoulder products judging by these characteristics, since nitrites were not added in its preparation. These findings, along with the product’s high sensory attributes similar to more popular products such as ham, would give more advantage for its acceptability and market demand
- Escalonamentos de tratamentos em unidades de saúdePublication . Leite, Ana; Pereira, Ana I.O problema de escalonamento de tratamentos em unidades de saúde é um tema atual na investigação operacional e bastante importante na área da gestão de hospitalar, estando associado à redução de custos com o pessoal especializado bem como a redução de tempo de espera dos utentes. Atualmente, os algoritmos evolutivos têm sido uma importante ferramenta para a resolução de problemas de escalonamento nas mais diversas áreas. Alguns dos métodos mais usados na área de escalonamento são o Algoritmo Genético e o método Particle Swarm Optimization. O Algoritmo Genético é conhecido por simular comportamentos biológicos, e é baseado no conceito da seleção e evolução natural e genética, usando a informação histórica para encontrar a solução ótima do problema. O método Particle Swarm Optimization é um método baseado no comportamento social de animais que não têm um líder. Este trabalho tem como objetivo desenvolver dois algoritmos baseados nos métodos Particle Swarm Optimization e Algoritmo Genético para a resolução de problemas de escalonamento de tratamentos em unidades de saúde. Com este estudo, podemos concluir que tanto os métodos Particle Swarm Otimization e o Algoritmo Genético apresentam soluções para todos os casos de estudo analisados, e ambos fornecem a mesma solução ótima para cada problema estudado com elevada rapidez de processamento.
- A Preliminary Evaluation of Sex and Dietary Field Pea Effects on Sensory Characteristics of Dry-Cured LoinsPublication . Argemí-Armengol, Immaculada; Álvarez-Rodríguez, Javier; Tor, Marc; Salada, Laura; Leite, Ana; Vasconcelos, Lia; Teixeira, Alfredo; Rodrigues, SandraTwo of the main issues related to cured meat products are castration to avoid boar taint and the hefty reliance on soybean meal to feed pigs. However, data on the effects of immunocastration in pigs and alternative crop protein feeds on the sensory traits and consumers' acceptance of dry-cured loin are still limited. A preliminary study was conducted on the effect of sex type (surgical castrated male pigs and immunocastrated male and female pigs, at approximately 140 kg in weight and 7 months of age) and animal diet (pea vs. soya) on dry-cured loins. The study involved a sensory evaluation of six treatments, with a 3 x 2 factorial design, conducted by trained panellists and untrained consumers in Spain (n = 126) and Portugal (n = 80). The consumers were also checked for their skatole sensitivity using a pure substance. The results showed that the pea-based diet was significantly different (p < 0.001) from the soy-based diet, as determined by a trained panel of surgically castrated male pigs, although the immunocastration treatments were not split. Dry-cured loin from immunocastrated male pigs fed with peas was considered tenderer and juicier (p < 0.05) than those fed soya-based diets. The untrained consumer panel scored higher on the sensory traits (flavour, juiciness, and overall liking) from the loin samples of surgically castrated male pigs fed a pea diet. All consumers scored similarly in boar taint detection. This study demonstrates the applicability of the pea-based diet for the feeding of pigs destined for cured meat and highlights immunocastration as a tool that does not compromise the skatole detection score.
- Incorporating Olive By-Products in Bísaro Pig Diets: Effect on Dry-Cured Product QualityPublication . Leite, Ana; Vasconcelos, Lia; Lopez, Sergio; Outor-Monteiro, Divanildo; Pinheiro, Victor; Rodrigues, Sandra; Teixeira, AlfredoThe objective of this study was to assess the impact of incorporating olive cake into the diet of indigenous Bísaro pigs on the quality of processed meat products. To this end, loins and “cachaços” were processed using a standardized manufacturing flowchart to produce dry-cured products. The two products were manufactured using the same formulation, ingredients, and curing process. Concerning the physicochemical composition, there were significant differences between the two products for the parameters of aw (p < 0.001), moisture (p < 0.001), total fat (p < 0.001), protein (p < 0.001), and haem pigments (p < 0.001). The diet significantly impacted the NaCl content (p < 0.05). However, neither the product nor the diet affected the fractions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), or polyunsaturated fatty acids (PUFA) (p > 0.05). However, a significant difference was observed for n-3 (p < 0.05). Adding olive cake increased these fatty acids, and the diet containing 25% centrifuged olive cake showed the highest levels for both products. Compared with the control, the diets containing olive cake had a higher content of n-3 fatty acids, resulting in a lower PUFA n-6/n-3 ratio (p < 0.01).