Valorization of fish from the Adriatic Sea: nutritional properties and shelf life prolongation of Aphia minuta through essential oils.

This study aimed to exploit the nutritional and microbiological qualities of Aphia minuta, which are still largely unknown; they are collected from Golfo di Manfredonia (Adriatic Sea). Chemical composition, fatty acids, and amino acid profiles were evaluated during winter, spring, and summer (two samples each season). The protein content was highest in spring, while no significant differences were found for fat and ash contents across all sampling periods. Fatty acid profile analyses revealed that monounsaturated and polyunsaturated fatty acids were affected by the sampling season. Notably, the value of n-3 polyunsaturated fatty acids increased in spring and summer compared to the winter season. The highest content of essential amino acids was measured during the spring and summer seasons (P < 0.01), with leucine and lysine being the most dominant. Regardless of the fishing season, from a nutritional point of view, this species is an excellent source of bioactive compounds. This study also focused on the microbiological quality and shelf life of Aphia minuta. Initially, the bioactivity of three different essential oils (thymol, lemon, and citrus extract) was tested on Pseudomonas fluorescens, Staphylococcus aureus, and Escherichia coli. These essential oils were then combined with various packaging materials (conventional, maize starch, and polylactate) and packaging atmosphere (air, vacuum, and a modified atmosphere with reduced oxygen content). The results indicated that combining citrus extract with vacuum packaging significantly reduced the psychrotrophic viable count to undetectable levels after 7 days. This study suggests some important considerations for exploiting and expanding the market of the Aphia minuta.

Mussel Culture Farming Systems in the Northern Gargano Coast (Adriatic Sea): Changes in the Nutritional Profile of the Mytilus galloprovincialis.

The objective of this study was to investigate the nutritional characteristics of Mytilus galloprovincialis cultivated in three sites of the Northern Coastal Area of Gargano. The mussel farms were characterized by different distances of dropper ropes (extensive dropper ropes: EDR; intensive dropper ropes: IDR; semi-intensive dropper ropes: SIDR). Mussels' chemical composition, fatty acids, and amino acids profiles were investigated at monthly intervals, from April to June. The fat content of mussels from EDR and SIDR sites was lower than values observed for mussels of the IDR in both the April and June sampling months. An increase in the main saturated fatty acids (C15:0; C16:0; C17:0 and C18:0; p < 0.001) and polyunsaturated fatty acids (C18:2c9c12, C18:3n3, C20:2n6, C20:4n6, and C22:6n3; p < 0.001) was found in the mussels collected in June from all farms analyzed. In terms of farming systems, mussels from the EDR and SIDR sites exhibited the greatest content of beneficial molecules like conjugated linoleic acids isomers (p < 0.001), glutamic acid (p < 0.05), serine (p < 0.05), tryptophan (p < 0.001), hydroxyproline (p < 0.05) and proline (p < 0.01). This study revealed that the farming system can affect the nutritional composition of mussels and evidenced that EDR and SIDR are the most effective cultured farming methods in the Gargano area.

Immunomodulatory Role of Rosmarinus officinalis L., Mentha x piperita L., and Lavandula angustifolia L. Essential Oils in Sheep Peripheral Blood Mononuclear Cells.

Recently, the uses of essential oils (EOs) as rumen modifiers, anti-inflammatory agents, and antioxidants were demonstrated in livestock. In the present study, the role of Mentha x piperita L. (MEO), Rosmarinus officinalis L. (REO), and Lavandula angustifolia L. (LEO) EOs in an in vitro sheep model of inflammation was investigated. With this aim, peripheral blood mononuclear cells (PBMCs) were treated with incremental concentrations (3, 5, 7, and 10%) of each EO to test their effects on cell viability and proliferation and on interleukin (IL)-6, IL-10, and IL-8 secretion. The PBMCs were stimulated by Concanavalin A (ConA) alone or in combination with lipopolysaccharide (LPS) mitogen. The positive and negative controls were represented by PBMCs in the presence or absence, respectively, of mitogens only. The cell viability and proliferation were determined by XTT and BrdU assays, while the cytokines were analyzed by ELISA. The EO treatments did not affect the viability; on the contrary, the PBMC proliferation increased in presence of all the EOs tested, according to the different percentages and mitogens used. The IL-10 secretion was higher in both the REO and the LEO tested at 3% than in the positive control; furthermore, the IL-8 level was influenced differently by the various EOs. The present data demonstrate that EOs may modulate the immune response activated by inflammation.

Red Meat Heating Processes, Toxic Compounds Production and Nutritional Parameters Changes: What about Risk-Benefit?

The heating process is a crucial step that can lead to the formation of several harmful chemical compounds in red meat such as heterocyclic aromatic amines, N-Nitrosamines, polycyclic aromatic hydrocarbons and acrylamide. Meat has high nutritional value, providing essential amino acids, bioactive compounds and several important micronutrients which can also be affected by heating processes. This review aims to provide an updated overview of the effects of different heating processes on both the safety and nutritional parameters of cooked red meat. The most-used heating processes practices were taken into consideration in order to develop a risk-benefit scenario for each type of heating process and red meat.

Improving meat tenderness using exogenous process: The consumer response.

The aim of this paper is to investigate purchase intention (PI) for meat obtained through a tenderization process based on a treatment with exogenous proteolytic enzymes. Particularly, perceived risks and perceived benefits on the consumer acceptance of tender meat produced through this emerging technology have been evaluated. In order to achieve the stated objective, a survey was conducted on a national representative sample of Italian consumers (N = 1006), who received information about the traditional and the emerging tenderization processes. Principal Component Analysis and Structural Equation Model were applied to the collected data. Results show that consumer purchase intention for meat treated with exogenous proteolytic enzymes was strongly influenced by perceived benefits and weakly influenced by perceived risks. Another important result is that perceived benefits are mainly affected by trust in science. Finally, a Cluster Analysis was performed to distinguish consumer segments with different response patterns.

Proteomics in bovine semitendinosus muscle to assess emerging strategies based on papain injection and ultrasounds on meat tenderization process.

The impact of papain and/or ultrasound treatments on tenderization of semitendinosus muscle through a proteomic approach was studied. Sixteen bovine muscles were submitted to the following treatments: aging at 3 °C (Control), papain injection (PI), ultrasound (US), PI followed by US (PIUS) and US followed by PI (USPI). pH, myofibrillar fragmentation indices (MFI), soluble collagen, texture profile and changes of myofibrillar proteins were investigated after 2, 24, 48 and 96 h of storage. The highest MFI and soluble collagen content were found in PI, PIUS and USPI samples while control samples showed the lowest values. PI samples showed the lowest WBSF and hardness values until 48 h of storage while at 96 h meat from USPI treatment showed WBSF value comparable to PI treatment. The lowest values of cohesiveness, gumminess and chewiness were found in PI samples during all storage times. Proteomic analysis revealed a different quantity and expression of proteins among tenderization treatments. US treatment did not exhibit a significant ability to degrade muscle proteins, while, all treatments containing papain, showed a greater ability to hydrolyse and degrade myofibrillar proteins. PI promoted intense proteolysis leading to an early tenderization process; on the contrary, in PIUS and USPI treatments the sequence of treatments was relevant on meat tenderization. Particularly, USPI treatment, after 96 h, reached the same improvement in tenderness of enzymatic treatment but with slower hydrolysing rate; this could be determinant to preserve textural structure.

Effect of hazelnut skin by-product supplementation in lambs' diets: Implications on plasma and muscle proteomes and first insights on the underlying mechanisms.

This study aimed to evaluate the effect of hazelnut skin by-product supplementation on lamb meat quality characteristics and plasma and muscle proteomes. Twenty-two Valle del Belice male lambs were divided into two experimental groups: control (C), fed a maize-barley diet and hazelnut (H), fed hazelnut skin by-product as maize partial replacer in the concentrate diet. The meat of lambs fed hazelnut skin showed greater values of lightness, redness, yellowness, and chroma color parameters together with the highest myofibril fragmentation index. Two-dimensional electrophoresis and mass spectrometry applied on plasma proteome identified 20 protein spots corresponding to 18 unique gene names to be differently expressed due to hazelnut skin by-product substitution. For the early post-mortem muscle, 23 protein spots (42 unique gene names) were significantly up-regulated due to hazelnut skin by-product supplementation. Four proteins these being APOA1, PHB, ACTG1 and ALB, were found to be common to the two proteomes suggesting that these proteins could be candidate biomarkers to monitor in vita and post-mortem lamb meat quality traits. This study evidenced the main mechanisms involved in the supplementation of hazelnut skin by-product in lambs' diet and confirmed the possibility of using plasma proteome as a non-invasive way to predict lamb meat quality. SIGNIFICANCE: Maximizing the use of agro-industrial by-products as replacers of traditional feedstuff for improving animal products is one of the important challenges to preserving natural resources and guaranteeing environmental sustainability. Hazelnut (Corylus avellana L.) skin, obtained as a results of hazelnut roasting, represents a valuable by-products due to its high content in unsaturated fatty acids, tannins, and vitamins. Thus, including hazelnut skin by-product in small ruminant nutrition could reduce the costs of animal feedings for farmers as well as improve meat nutritional and sensorial characteristics. Additionally, monitoring the meat quality characteristics with fast, accurate, and non-invasive tools to find, before slaughter, animals with desired quality characteristics is of growing interest in the last years. In this regard, the objectives of this study were to assess i) the effect of hazelnut skin supplementation on lamb meat quality characteristics and plasma and muscle proteomes, and ii) whether analyzing plasma proteome by using a gel-based proteomic approach could effectively offer a more readily available option for determining lamb meat quality. Taken together, the proteomic approach applied to plasma and muscle proteomes, allowed us to reveal the pathways and the potential candidate plasma biomarkers to predict lamb meat production in the pre-slaughter phase.

Postmortem Muscle Protein Changes as a Tool for Monitoring Sahraoui Dromedary Meat Quality Characteristics.

The effects of slaughter age (2 vs. 9 years) and postmortem time (6, 8, 10, 12, 24, 48 and 72 h) on the meat quality and protein changes of the longissimus lumborum muscles of the Algerian Sahraoui dromedary were investigated. Muscles of young dromedaries evidenced a slower acidification process and a significantly higher myofibrillar fragmentation index throughout the postmortem time. The SDS-PAGE of sarcoplasmic and myofibrillar proteins revealed that meat from young dromedaries was characterized by the lowest percentage of myoglobin (p < 0.001) and the highest percentage of desmin (p < 0.01). During postmortem time, a decrease was found for phosphoglucomutase (p < 0.01), α-actinin (p < 0.05) and desmin (p < 0.01) in meat from young dromedaries. Western blot revealed an intense degradation of troponin T in younger dromedaries, with an earlier appearance of the 28 kDa polypeptide highlighting differences in the proteolytic potential between dromedaries of different ages. Principal component analysis showed that meat from young dromedaries, starting from 24 h postmortem, was located in a zone of the plot characterized by higher levels of the myofibrillar fragmentation index, 30 kDa polypeptide and enolase, overall confirming greater proteolysis in younger animals. Data suggest that the investigation of the muscle proteome is necessary to set targeted interventions to improve the aging process of dromedary meat cuts.

Nutritional Profile of Donkey and Horse Meat: Effect of Muscle and Aging Time.

The aim of this study was to evaluate the effect of 14-day vacuum aging on the nutritional composition of donkey and horse meat. Longissimus Dorsi (LD), Semimebranosus (SM), and Rectus Femoris (RF), Semitendinosus (ST) muscles were sampled from each left carcass of 12 donkeys and 12 horses, respectively. Each muscle was divided into three sections, vacuum packaged, and stored at 2 °C for different aging times (1, 6, and 14 days). Fatty acids, amino acids, and cholesterol content were determined. SM exhibited higher levels of polyunsaturated fatty acids (PUFA) both in donkey and horse, whereas LD evidenced higher saturated (SFA) and monounsaturated (MUFA) fatty acids and lower cholesterol content in horse after 1, 6, and 14 days of storage. An aging effect was found only in donkey meat with higher saturated fatty acids and lower PUFA content at the end of the aging period. The highest value of essential amino acids has been displayed in SM an LD muscles from horse and donkey, respectively. Our results highlighted that equine meat, due to an excellent nutritional profile, represents a healthy alternative to traditionally consumed red meat. A different aging method could be used in donkey meat to preserve the high PUFA content.

Proteomic analysis to understand the relationship between the sarcoplasmic protein patterns and meat organoleptic characteristics in different horse muscles during aging.

The study investigates the changes in meat organoleptic characteristics and sarcoplasmic proteins of 3 horse muscles during aging. Longissimus lumborum (LL), semimembranosus (SM) and semitendinosus (ST) muscles, were removed from 12 Italian Heavy Draft Horse carcasses and aged for 1, 3, 6, 9 and 14 days. The lowest values of hardness and chewiness were found in LL muscle. During aging, a decrease of hardness was observed in ST muscle reaching the lowest value at 14 days. 2DE revealed a decrease of 15 sarcoplasmic protein spots in all muscles. Muscle-differences were found at 14 days. An increase of tropomyosin spots was found in LL muscle while, ST was characterized by a rise of superoxide dismutase, phosphoglucomutase-1 and two isoforms of myoglobin. Principal component analysis applied to color, texture parameters and spots volume differentiated the muscles into three different clusters. Data revealed that myofibrillar, glycolytic and mitochondrial proteins are potential muscle-biomarkers to monitor post-mortem processes and meat quality characteristics in horse meat.

Lamb Meat Quality and Carcass Evaluation of Five Autochthonous Sheep Breeds: Towards Biodiversity Protection.

In the present study, the evaluation of the carcasses and meat quality, in terms of chemical composition and fatty acid profile, of lambs from five autochthonous sheep breeds (Altamurana, Bagnolese, Gentile di Puglia, Laticauda, and Leccese) reared in continental Southern Italy, were studied. All the carcasses were evaluated according to the EU Mediterranean classification system for carcasses weighing less than 13 kg. Meat chemical composition and fatty acids profile were assessed on both loin and leg commercial cuts. Fatty acid composition of loin resulted in differences among breeds, displaying lower values of saturated fatty acid in Altamurana, Bagnolese, and Leccese breeds and the highest content of polyunsaturated fatty acid in the Altamurana breed. Principal component analysis grouped lamb according to fatty acid content and to conjugated linoleic acid (CLA), omega n-3 and n-6 fatty acids; thus, Altamurana, Bagnolese, and Leccese breeds are characterized by the highest values of CLA content. Our data demonstrated that lamb meat from autochthonous breed has good carcass quality and the content of CLA, n-3, and n-6 was valuable for human consumption; therefore, the valorisation of local meat quality can help to avoid the extinction of the autochthonous breed offering to the market and consumer's high nutritive products.

NETosis of Peripheral Neutrophils Isolated From Dairy Cows Fed Olive Pomace.

Neutrophils represent primary mobile phagocytes recruited to the site of infection, and their functions are essential to enhance animals' health performance. Neutrophils have an essential role in innate immunity and are able to kill the pathogens via the synthesis of neutrophil extracellular traps (NETs). The objective of the present work was the study of the in vitro NETosis of peripheral neutrophils isolated from dairy cows supplemented with olive pomace. Dairy cows (n = 16) balanced for parity (3.67 ± 1.5 for CON, 3.67 ± 1.9 for OP), milk yield (24.3 ± 4.5 kg d-1for CON and 24.9 ± 1.7 kg d-1 for OP), the number of days in milk (109 ± 83.5 for CON and 196 ± 51 for OP), and body weight (647 ± 44.3 kg for CON and 675 ± 70.7 kg for OP) were divided into two experimental groups fed with a control diet (CON) and supplemented with 6% of olive pomace (OP). Peripheral blood neutrophils were isolated and stimulated in vitro with phorbol-myristate-acetate (PMA) as a marker for activation and reactivity of the neutrophils. After isolation, both the viability and CD11b expression were analyzed by flow cytometry. Both NETosis by neutrophil elastase-DNA complex system and myeloperoxidase (MPO) activity were evaluated by ELISA. The specific antibodies against MPO and citrullination of Histone-H1 were used for investigating NETosis by immunofluorescence microscopy. The neutrophil elastase-DNA complexes produced during NETosis and MPO activity of neutrophil extracts were affected by OP supplementation. Furthermore, results from immunofluorescence analysis of NETosis depicted a similar result found by ELISA showing a higher expression of MPO and citrullination of Histone-H1 in OP than the CON neutrophils. In addition, all data showed that the OP diet resulted in a better response of neutrophils to PMA stimulation than the CON diet, which did not support the neutrophils' responses to PMA stimulation. Our results demonstrated that OP supplementation can enhance the neutrophil function in dairy cows leading to udder defense and inflammation response especially when an immunosuppression state can occur.

How Volatile Compounds, Oxidative Profile and Sensory Evaluation Can Change with Vacuum Aging in Donkey Meat.

This study aims to improve knowledge on donkey meat and the vacuum aging effect on the Volatile Organic Compounds (VOCs), oxidative profile and status and the sensory characteristics. Ten 18-month old Martina Franca donkeys' male foals were involved in the trial. Longissimus thoracis (LT) muscle was extracted from each left half carcass, between the fourth and the ninth rib. Each muscle was divided into five sections, vacuum packaged, stored at 2 °C, and randomly assigned to one of the different aging time (1, 3, 6, 9, and 14 days of aging). Volatile compounds, oxidation parameters, and antioxidant enzymes were analysed, and a sensory test was performed. A nested one-way analysis of variance (ANOVA) was performed for aging time as an independent variable. Significance was set at p < 0.05. Aldehydes are the most produced VOCs, but no changes were observed during vacuum aging (p > 0.05). Nitrogen compounds increased during aging (p < 0.01). TBARs and hydroperoxides did not change during the storage, whereas the protein carbonyls increased (p < 0.05). Vacuum aging slowed down lipid oxidation and put in evidence the presence of protein oxidation and degradation, influencing the VOCs productions and sensory evaluation.

Volatile Organic Compounds, Oxidative and Sensory Patterns of Vacuum Aged Foal Meat.

The study aimed to evaluate the effect of 14-day vacuum aging on the volatile compounds (VOC) profile, oxidative profile, antioxidant enzymes activity, and sensory evaluation in the Longissimusthoracis muscle of foal meat under vacuum aging. Longissimusthoracis (LT) was sampled in 20 mm thick slices, vacuum packed, and stored at 4 °C. Samples were randomly assigned to different aging times (1, 6, 9, 14 days after slaughtering). VOCs, thiobarbituric acid reactive substances (TBARs), hydroperoxides, carbonyl proteins, superoxide dismutase, catalase, and glutathione peroxidase were analyzed, and a sensory test was performed. A nested one-way analysis of variance (ANOVA) was performed for aging time as an independent variable. Significance was set at p < 0.05. The main VOCs originating from cooked steaks were aldehydes, (from 47.18% to 58.81% of the total volatile compounds), followed by hydrocarbons (from 9.32% and 31.99%). TBARs and hydroperoxides did not show variations due to aging (p > 0.05), instead, protein carbonyls showed higher values at the 14th day (p < 0.01). Catalase, superoxide dismutase, and glutathione peroxidase showed increasing values during aging time (p < 0.01). Vacuum aging slowed down lipid oxidation, and protein oxidation was shown to be present. However, the best vacuum aging duration is in the range of 6-9 days from slaughtering, with an improvement of sensory evaluation.

Effect of information on geographical origin, duration of transport and welfare condition on consumer's acceptance of lamb meat.

Animal production system and welfare conditions can influence consumers' acceptance, as meat from animals grazing in natural pasture and labelled with information about high standards of welfare is preferred. In addition, geographical origin of food is recently considered one of the main information influencing the consumers' acceptance. Local products are collectively associated with high quality attributes by the consumers related to shorter transport and good welfare. Lamb meat is considered local and typical food; however, it is common to find in the same market both local and imported lamb meat. The present investigation aimed at understanding the importance of information about geographical origin, transport duration, and welfare condition of lambs for consumers and their actual liking. Moreover, the quality of lamb meat from local and imported animals as affected by short or long transport was assessed. Data demonstrated that both short and long transport did not affect organoleptic quality of meat; this result was corroborated by an absence of both metabolic and immune stressors in long term transport lambs except for haptoglobin, cortisol and glucose. However, the expected and actual acceptability were affected by the information with higher scores for local lamb when information on the geographical origin, transport duration, and welfare condition was provided to the consumers.

Application of proteomic to investigate the post-mortem tenderization rate of different horse muscles.

The aim of this study was to evaluate the effect of post-mortem aging on tenderness development and proteolysis of myofibrillar proteins in 3 different horse muscles. Warner-Bratzler shear force decreased during aging in all muscles, showing the lowest values in longissimus lumborum (LL) in all sampling points. Myofibril fragmentation index significantly increased in LL and semimembranosus (SM) muscles throughout aging time whereas in semitendinosus (ST) it increased after 14 days of aging. Proteomics analysis revealed the major content of intact myofibrillar proteins with high molecular weight in ST muscle in the first phase of aging, while, after 14 days a higher accumulation of TnT-derived polypeptides and spots isoforms ascribed to MLC2 and MLC1 proteins were found. Data highlight that aging affects the meat tenderness and proteolysis with different intensities in each muscle and suggest that a more extensive post-mortem proteolysis occurred in ST muscle.

Effect of lipid fraction of digested milk from different sources in mature 3T3-L1 adipocyte.

We evaluated the effect of in vitro digested milk on mature adipocytes 3T3-L1, paying particular attention to its fatty acid composition, and comparing human (HM), donkey (DM), bovine (BM), ovine (OM), caprine (CM) and formula (FM) milk. Cellular viability, apoptosis, oxidative response and gene expression levels of NF-κB p65, HMGB1, SREBP-1c and FAS were evaluated. Digested milk treatments significantly reduced 3T3-L1 mature adipocytes viability and caspase activity compared with control group, but no significant differences were observed among different sources of digested milk. In all digested milk samples, ROS level was higher than the control, however, the digested human and formula milk showed lower levels of ROS than DM, BM, OM and CM samples. Lower capacity of HM and FM to induce oxidative stress in mature adipocytes was ascribed to the peculiar free fatty acids profile of digested milk samples. All milk treatments elicited a significant over-expression of NF-κB p65 in 3T3-L1 adipocytes compared to the control; the lowest gene expression was found in HM, BM, OM and CM, the highest in FM and an intermediate behavior was shown in DM. All digested milk treatments influenced the gene expression of SRBP-1c with FM and HM showing the highest levels. For FAS expression, BM showed the highest level, OM and CM intermediate and FM, HM and DM the lowest levels, however HM and DM had comparable levels to the control.

Ultrasound processing of fresh and frozen semi-skimmed sheep milk and its effects on microbiological and physical-chemical quality.

The objective of this study was to evaluate the effect of ultrasound treatment on the microbiological quality, protein and free amino acid profile of fresh and frozen stored semi-skimmed sheep milk. Milk was treated as fresh or frozen and stored up to one, three and six months. Output power time and pulse time were the parameters combined to design four different ultrasound (US) treatments: power 78 W and duration 6 min (US1); power 78 W and duration 8 min (US2); power 104 W and duration 4 min (US3) power 104 W and duration 6 min (US4). Pulse duration was of 4 s for each treatment. Sample US1 was discarded due to non effectiveness of US treatment, while other samples showed interesting results. Also, it was verified a frost effect on microorganisms in all samples which were frozen before treatment. No relevant change was reported on amino acid profile. The study showed promising results: the ultrasound treatment inactivated or eliminated the studied contaminant bacteria in semi-skimmed sheep milk, while maintained acceptable amount of lactic bacteria, which could be advantageous for dairy products processing.

Foal meat volatile compounds: effect of vacuum ageing on semimembranosus muscle.

BACKGROUND: Cooked meat flavor arises through a combination of thermally generated aroma volatile and nonvolatile compounds in a matrix of muscle fiber, connective tissue, and fat. Ageing could affect meat odor, taste, and flavor by the development of odor compounds in the raw product. The aim of the work is to assess the ageing effect on the volatile compounds profile by solid-phase microextraction and gas chromatography-mass spectrometry analysis of foal meat vacuum packaged for storage at 4 °C for a period of 14 days. RESULTS: Only pentane and 3,7-dimethylnonane were significantly affected by ageing time (P < 0.01). Octanal and nonanal presented an increasing trend with higher values at 14 ageing days compared with six ageing days (P < 0.01). CONCLUSIONS: Ageing poorly affects the volatile compounds production of foal meat. Probably, 14 days is considered to be a short maturation time in vacuum packaging for foal meat. © 2018 Society of Chemical Industry.

Effect of Diet Supplementation with Quinoa Seed and/or Linseed on Immune Response, Productivity and Meat Quality in Merinos Derived Lambs.

In the last years several studies have investigated the strong relation between nutrition and immune response in the livestock production, particularly in dairy cattle and sheep. The aim of this study was to evaluate the effects of supplementation based on linseed, quinoa seeds and their combination on welfare, productivity and quality of meat from merinos derived lambs. 32 weaned lambs were divided into 4 experimental groups: quinoa (Q), linseed (LS) and combination of quinoa and linseed (LS + Q) that received the respective supplementation and control group (C) without supplementation. Lambs from all supplemented groups showed lower plasma urea, creatinine and cholesterol than control. Both linseed and quinoa supplementation enhanced the cell-mediated immune responses of lambs, furthermore, linseed supplementation resulted in the lowest level of cortisol secretion after handling, loading and transport. Meat from lambs supplemented with linseed and LS + Q showed the highest pH, at 1 and 3 h post-mortem, while, meat from all supplemented groups was more tender than meat from control. Results indicated that linseed and quinoa seeds supplementation can help the animal to cope with stressful events due to the close link between stress responses and the immune system and for improving meat quality in terms of better tenderness.