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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
- A review of the use of oleogels to improve the quality of sheep and goat meat productsPublication . Teixeira, Alfredo; Leite, Ana; Vasconcelos, Lia; Rodrigues, SandraGlobal demand for healthy, sustainable meat is rising due to consumer preferences for nutritious options. Sheep and goat meat, valued for flavor and leanness, require innovative quality assurance, especially outside Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI) labels. Oleogels, solid at room temperature but melting at body temperature, enhance meat quality by replacing saturated fats with healthier unsaturated fats, aligning with health-conscious consumer trends. They also reduce environmental impact and cardiovascular risks. Oleogels maintain meat’s mouthfeel and texture, aiding in the development of healthier, sustainable products. While gelled emulsions show promise as fat replacers, their use in sheep and goat meat is largely untapped. This review highlights oleogels’ potential in transforming these meats, focusing on formulation, functionality, and benefits, to meet consumer demands for healthier, sustainable options
- Use of olive pomace in the Bísaro breed feeding: effect on processed meat products sensory qualityPublication . Rodrigues, Sandra; Vasconcelos, Lia; Leite, Ana; Ferreira, Iasmin da Silva; Pereira, Etelvina; Teixeira, AlfredoThis work aimed to evaluate the effect of feeding animals with olive pomace on the sensory characteristics of Bísaro pork transformed products: dry-cured loin and neck. Five treatments were studied considering the process of obtaining the olive pomace: pressed (PoPr), centrifuged (PoCf), and extracted (PoEx and PoExOO) olive pomace, compared with the control (Ct). Animals were fed with olive pomace for 2 weeks before slaughter. In 4 different times, 2 animals per treatment were slaughtered, meaning 10 animals each time, 40 animals in total. Dry-cured loins and necks were produced in the meat manufacturing industry Bísaro Salsicharia according to traditional practices. Twenty-one appearance, odour, texture, and taste attributes were evaluated by 8 members trained taste panel. All treatments were evaluated in duplicate in each of 3 sessions. A nonparametric ANOVA was performed for related samples, with pairwise comparisons by Friedman’s test. Results showed no significant differences between treatments for all quantitative sensory attributes evaluated in the cured loins of Bísaro pork under study. In the cured neck, there was a significant influence of the treatment on the muscle/fat ratio. PoCf and PoEx had a significantly lower muscle/fat ratio, that is, more fat than muscle than Ct, and at the same time PoPr and PoExOO were not significantly different from one or the other. We can conclude that olive pomace can be used in pigs’ diets with no significant influence on their processed meat products’ sensory characteristics, adding value to an undervalued subproduct from olive oil production.
- 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.
- An approach to predict chemical composition of goat Longissimus thoracis et lumborum muscle by Near Infrared Reflectance spectroscopyPublication . Teixeira, Alfredo; Oliveira, António Filipe Gomes de Faria; Paulos, Kátia; Leite, Ana; Marcia, Anabela; Amorim, André; Pereira, Etelvina; Silva, Severiano; Rodrigues, SandraThe ability of near infrared reflectance spectroscopy (NIRS) to estimate the protein, moisture, connective tissue and ash content in the Longissimus thoracis et lumborum (LTL) muscle of goat was studied. Samples (n=240) of the LTL muscle were taken from the 8th to 13th rib cut of goat carcasses. Samples were scanned in a FT-NIR Master™ N500 (BÜCHI) over a NIR spectral range of 4000-10,000cm < sup > -1 < /sup > with a resolution of 4cm < sup > -1 < /sup > . It was collected 3 spectra per sample and subsequently, chemical analyses were performed at the Carcass and Meat Quality Laboratory of ESA-IPB. Using NirCal 1.5 it was developed a PLS regression model assaying, first and second derivatives as math treatment and multiplicative scatter correction for minimizing scattering effect on the spectra database recorded (n=240). The best calibrations' models show relatively good predictability for protein (standard error of prediction SEP=0.43; coefficient of determination R < sup > 2 < /sup > =0.91), moisture (SEP=0.48; R < sup > 2 < /sup > =0.92). Calibrations' models obtained are important as a first attempt to predict the chemical composition of goat meat by NIRS. More experimental data are needed to improve the accuracy of these calibrations.
- Use of Black Pepper Essential Oil to Produce a Healthier Chicken PâtéPublication . Rodrigues, Sandra; Leite, Ana; Vasconcelos, Lia; Pereira, Etelvina; Seixas, Natália; Estevinho, Letícia M.; Teixeira, AlfredoThis study aims to explore the effect of using black pepper essential oil (BPEO) to produce a healthier chicken pâté. Four different formulations were produced: a control formulation without back pepper and three with increasing BPEO contents. To test the effect of using BPEO, physiochemical analyses were performed at two different moments, 8 and 21 days after production. Microbiological analyses were performed 2, 9, 16, and 23 days after production. Sensory analysis to evaluate the pleasantness of the pâtés to consumers was performed 21 days after production. Finally, total phenol and flavonoid content and antioxidant activity were evaluated. Results show no significant physicochemical differences. Pâtés with no BPEO or black garlic were the most pleasant, but 0.3 or 0.5% of BPEO were not significantly less appreciated, while 1% of the EO caused a decrease in taste and global appreciation. The higher the BPEO content, the higher the phenol content, antioxidant (with an increase from 1.58 to 2.27 mg eq. Fe II/g of sample, in the Control at T23 and V3 at T23, respectively), and microbial activity (with total mesophiles count reduction from 5.91 to 5.21 log CFU/g sample in V3 from T9 to T16). The use of 1% of BPEO showed a significant effect on the reduction in mesophile counts for at least two weeks. These results highlight the potential for optimizing BPEO or black garlic content to ensure both consumer acceptance and enhanced functional properties. While further analysis will help pinpoint the best formulation, the current findings are a promising step towards achieving an optimal balance.
- Physicochemical composition and sensory quality of goat meat burgers. Effect of fat sourcePublication . Teixeira, Alfredo; Ferreira, Iasmin da Silva; Pereira, Etelvina; Vasconcelos, Lia; Leite, Ana; Rodrigues, SandraSeveral strategies for producing healthier meat products have been developed. Reducing fat content, using different fat sources, modifying and improving the fatty acid profile or even replacing saturated fat with oleogels are some of the methods used. Goat meat mainly from animals out of quality brands with low commercial value can be valorized when processed, giving the opportunity to increase its consumption and acceptability. Thus, the aim of this study was to study the effect of the replacement of pork as a source of fat with an olive oleogel in burgers manufactured with goat meat and to compare the goat meat burgers with the most common commercial burgers made with beef. Two replications of the burgers were manufactured at different times, and three samples of each burger type (GOO—goat meat burgers with olive oil; GPF—goat meat burgers with pork fat) were randomly selected from each lot manufactured. Each sample was analyzed in triplicate for each physicochemical analysis. At the time, the manufactured burgers were analyzed simultaneously with the commercial burgers. The burgers with olive oil (GOO) showed higher a* and b* than the burgers with pork fat (GPF) and consequently had lower h° and C*. The ashes, protein and collagen contents of the GOO and GPF burgers were similar to those of the other goat meat products. The effect of the incorporation of oleogel on the physicochemical composition of the burgers in relation to the pork fat was expressed in the fat content, 4 and 2.78% for GOO and GPF, respectively. CH burgers have significantly higher fat content (13.45%) than GOO and GPF burgers. The replacement of pork backfat with a vegetable oleogel modified the fatty acids profile, since the GOO burgers had the highest MUFA and PUFA and the lipidic quality, defined by the IA and IT indices, was 0.38 and 0.99, respectively. Globally, goat burgers were sensorially harder and presented a more difficult chewiness than CH. The replacement of the pork back fat with oleogel significantly decreased hardness and chewiness.
- Can near-infrared spectroscopy replace a panel of tasters in sensory analysis of dry-cured bísaro loin?Publication . Vasconcelos, Lia; Dias, L.G.; Leite, Ana; Ferreira, Iasmin da Silva; Pereira, Etelvina; Bona, Evandro; Mateo, Javier; Rodrigues, Sandra; Teixeira, AlfredoThis study involved a comprehensive examination of sensory attributes in dry-cured Bísaro loins, including odor, androsterone, scatol, lean color, fat color, hardness, juiciness, chewiness, flavor intensity and flavor persistence. An analysis of 40 samples revealed a wide variation in these attributes, ensuring a robust margin for multivariate calibration purposes. The respective near-infrared (NIR) spectra unveiled distinct peaks associated with significant components, such as proteins, lipids and water. Support vector regression (SVR) models were methodically calibrated for all sensory attributes, with optimal results using multiplicative scattering correction pre-treatment, MinMax normalization and the radial base kernel (non-linear SVR model). This process involved partitioning the data into calibration (67%) and prediction (33%) subsets using the SPXY algorithm. The model parameters were optimized via a hybrid algorithm based on particle swarm optimization (PSO) to effectively minimize the root-mean-square error (RMSECV) derived from five-fold cross-validation and ensure the attainment of optimal model performance and predictive accuracy. The predictive models exhibited acceptable results, characterized by R-squared values close to 1 (0.9616–0.9955) and low RMSE values (0.0400–0.1031). The prediction set’s relative standard deviation (RSD) remained under 5%. Comparisons with prior research revealed significant improvements in prediction accuracy, particularly when considering attributes like pig meat aroma, hardness, fat color and flavor intensity. This research underscores the potential of advanced analytical techniques to improve the precision of sensory evaluations in food quality assessment. Such advancements have the potential to benefit both the research community and the meat industry by closely aligning their practices with consumer preferences and expectations.
- 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.