Nutritional value of meat lipid fraction obtained from mallard duck (Anas platyrhynchos) reared in semiextensive conditions for hunting purposes.

The mallard duck or wild duck (Anas platyrhynchos) is the world's most widespread and numerous dabbling duck, being traditionally hunted across many countries in Europe and North America. This study aims to provide a detailed characterization of mallard duck's meat lipid fraction obtained from farmed specimens, reared for hunting purposes, under semiextensive conditions. The mallard's duck meat total lipid content averaged 2.0 and 4.26 g/100 g of fresh meat in breast and leg meat portions, and its meat comprised 23 individual fatty acids (FA) and 3 dimethylacetals (DMA), independently of the sex or meat portion. The oleic (C18:1 cis-9), palmitic (C16:0), stearic (C18:0), linoleic (C18:2n-6), arachidonic (C20:4n-6), palmitoleic (C16:1 cis-9), and cis-vaccenic (C18:1 cis-11) acids were the predominant FA (representing >1% of total fatty acids in both breast and leg meat portions and independently of the sex), and together, these 7 fatty acids were accountable for 92.4 to 96.5% of total FA plus DMA in mallard duck meat. The monounsaturated, saturated and polyunsaturated fatty acids were accountable for 40.4, 35.0, and 21.0% of total FA plus DMA in breast and 54.6, 38.7, and 5.7% of total fatty acids in leg, while total DMA were liable for 3.6 and 0.9% of total FA plus DMA in breast and leg, respectively. The mallard duck meat total cholesterol content averaged 49.8 and 57.1 mg/100 g of fresh meat for breast and leg meat portions. Five tocochromanols were quantified in mallard duck meat, affording it with a total vitamin E content of 5.48 and 3.63 µg/g of fresh meat in breast and leg portions. The sex had no influence (P > 0.05) on mallard's duck meat lipid composition, but meat portion had a strong influence on mallard's duck meat lipid composition, influencing total lipid, total cholesterol, total vitamin E contents, FA partial sums, FA ratios (exception made for the n-6/n-3 ratio), and all nutritional lipid indices. The breast meat presented lower total lipid and total cholesterol contents, better FA ratios and nutritional quality indices and higher vitamin E content, being regarded as a healthier meat than leg. The study presented herein shows that mallard duck production in semiextensive conditions, similar to those used herein, could be used for the production of mallard duck beyond hunting. A production of duck's meat under natural or organic production practices, oriented to a market niche within the gourmet/organic markets.

Evaluating dried salted cod amino acid signature for nutritional quality assessment and discriminant analysis.

Aim: Thus, the aim of this study was to answer three scientific questions: (1) Are the protein content and amino acid profile of dried salted cod influenced by species (Gadus morhua and Gadus macrocephalus)? (2) Are the protein content and amino acid profile of dried salted cod influenced by the geographical area of capture (Iceland and Norway)? and (3) Does the amino acid profile have the potential to be used as a discriminator of species and geographical areas of capture? Methods: A total of 45 dried salted cods (2-3 kg of dry weight; n = 15 samples/origin) were used in this study. The Atlantic cod was fished in the Atlantic northeast (FAO 27 area) within the Exclusive Economic zones (EEZ) of Norway (n = 15) and Iceland (n = 15), while the Pacific cod was caught in the Pacific northeast (FAO 67 area) within the Alaska EEZ (n = 15). Total protein content was determined by the Kjeldahl method, in accordance with the AOAC procedures. The amino acid profile was analyzed by HPLC with fluorescence detection (at excitation and emission wavelengths of 338 and 425 nm, respectively). Results: The Atlantic cod presented higher contents of total protein (33.90 versus 33.10 g/100 g of cod edible portion; p = 0.017) and total amino acid contents (32.52 versus 32.04 g/100 g of cod edible portion; p = 0.015) but displayed lower percentage of indispensable amino acids (32.16 versus 32.83 g/100 g of protein; p < 0.001) than Pacific cod. Among the Atlantic cod harvesting locations, the Norwegian cod displayed higher total amino acid contents (96.91 versus 96.81 g/100 g of protein; p = 0.012) and higher percentage of indispensable amino acids (35.38 versus 28.94 g/100 g of protein; p = 0.042) than the Icelandic counterpart. A correct classification of 100% was obtained for the Pacific and Icelandic cod varieties, but the classification accuracy in the Norwegian cod was of just 86.67%, since 2 samples out of 15 were incorrectly classified as Icelandic. Conclusion: The comparison of cod species showed that the Atlantic cod had a significantly lower EAAI than the Pacific cod (p < 0.001; 88.23 versus 88.61). On the other hand, the comparison of the two origins in the Atlantic cod, showed that Norwegian cod displayed a significantly higher EAAI than the Icelandic cod (99.15 versus 77.32). The assessment of the EAAI allows the classification of the protein's nutritional quality, allowing us to classify both cod species as a good protein source to human diet. However, within the Atlantic cod, the Norwegian cod's protein is classified as high quality, while the Icelandic cod attain the classification of useful quality. Regarding the amino acid profile discriminatory potential to classify cod samples. The results show that the AA profile has 100% accuracy in the separation of cod species, but was not globally efficient in the differentiation of the Norwegian from the Icelandic cod.

The composition of the lipid, protein and mineral fractions of quail breast meat obtained from wild and farmed specimens of Common quail (Coturnix coturnix) and farmed Japanese quail (Coturnix japonica domestica).

The present study was intended to answer 2 scientific hypotheses: 1) the quail species has a significant influence in quail breast meat composition; 2) the wild quail's meat presents healthier composition than their farmed counterparts. An analysis of the pectoral muscles of wild and captive common quails (Coturnix coturnix) and domestic quails (Coturnix japonica domestica) was performed. The content of fatty acids (FA), amino acids, total cholesterol, and vitamin E, some basic macro- and microminerals in the pectoral muscles of the 2 species of the genus Coturnix were analyzed. Regarding the quail species influence on meat composition, Japanese Quail (JQ) revealed better lipid composition, characterized by lower saturated FA (SFA; less 3.17 g/100 g of total fatty acids), higher polyunsaturated FA contents (PUFA; more 5.5 g/100 g of total fatty acids) and healthier polyunsaturated FA/saturated FA (P/S) and n-6/n-3 ratios and TI value (1.08, 9.54 and 0.60 vs. 0.76, 12.58, and 0.75, correspondingly). The absence of differences observed on amino acids partial sums and ratios reveals equality between species on protein nutritional quality. On the other hand, Common Quail (CQ) proved to be a better source of copper (0.181 mg/100 g of meat), iron (2.757 mg/100 g of meat), manganese (0.020 mg/100 g of meat), and zinc (0.093 mg/100 g of meat) than JQ. The comparison of farmed and wild specimens within CQ, showed that wild birds presented lower total cholesterol (less 8.32 mg/g of fresh meat) and total PUFA (less 4.26 g/100 g of total fatty acids), and higher n-3 PUFA contents (more 1.53 g/100 g of total fatty acids), which contributed to healthier P/S and n-6/n-3 ratios, but worst PI (1.60, 8.08, and 113.1 vs. 0.76, 12.58, and 100.8, respectively). The wild species revealed higher α-tocopherol content (2.40 vs. 1.49 µg/g of fresh meat. Differences observed on their mineral composition counterbalance each other. Under intensive production system and similar feeding and management conditions, the CQ develops better nutritional qualities than JQ. The comparison of wild and farmed species within CQ reveals more similarities than differences. Quail´s meat presents good nutritional quality and introduces variability to human's diet, which is much valued by consumers.

Cow's Milk in Human Nutrition and the Emergence of Plant-Based Milk Alternatives.

Cow's milk is considered a complete food, providing high-quality protein and essential micronutrients, including vitamins and minerals. For medical reasons or as a lifestyle choice, consumers are replacing cow's milk with plant-based milk alternatives (PBMA); some perceive them as healthier alternatives to cow's milk due to their low saturated fatty acid content and no cholesterol content. However, the nutritional composition of PBMA is quite variable between different types and even within, which makes a comparison with cow's milk a complex issue. Furthermore, the consumption of PBMA has been associated with the development of some diseases in infants and children. Meanwhile, the consumption of cow's milk in human health is a controversial issue since it has been associated with a favorable effect in some diseases (such as obesity, type 2 diabetes, and Alzheimer's) and a negative effect in others (such as prostate cancer risk and Parkinson's disease); while in some diseases, there is no consensus in the cow's milk consumption effect. The aim of this review is to make a nutritional comparison of cow's milk with PBMA and to clarify the potential health issues related to their consumption.

Susceptibility of dry-cured tuna to oxidative deterioration and biogenic amines generation: I. Effect of NaCl content, antioxidant type and ageing.

This study aimed to assess lipid oxidation and biogenic amine (BA) development in "muxama", a dry-cured tuna muscle product, as affected by salt content, antioxidant type and ageing time. Overall, BA contents decreased with NaCl level (2785.1mgkg-1, 1148.1mgkg-1 and 307.7mgkg-1) and increased with ageing time (366.2mgkg-1, 1711.8mgkg-1 and 2959.2mgkg-1 in the final product (T0), and after 1 (T1) and 3 (T3) months of ageing, respectively). Regardless of the test conditions, the most concentrated BA was always tyramine. For the ageing periods considered in the present study, malondialdehyde formation was affected by the NaCl level, with the saltiest samples exhibiting lower content. Rosemary and sage extracts represented promising technological options for preserving muxama from oxidation and to minimize the presence of a fishy flavour and odour, but this treatment may cause the colour to lose some of its redness and become less appealing.

Concentration of antioxidants in two muscles of mature dairy cows from Azores.

This study evaluated the concentrations of α-tocopherol, ß-carotene, creatine, carnosine, anserine and coenzyme Q10 in Longissimus dorsi (Ld) and Gluteus medius (Gm) muscles of culled dairy cows and the impact of age, production status before slaughter (dry-off vs lactating) and carcass weight on them. The effects of applying a finishing feeding regimen before slaughter were also examined. Gm muscle presented higher levels (P<0.001) of α-tocopherol (5.14 vs 3.61 µg · g(-1)) ß-carotene (0.36 vs 0.27 µg · g(-1)), anserine (59.24 vs 43.25 mg · 100 g(-1)) and coenzyme Q10 (3.33 vs 1.73 mg · 100 g(-1)), and by contrast lower (P<0.05) creatine concentration (502.40 vs 527.28 mg · 100 g(-1)) than Ld. Dry-off and lactating cows differed significantly in α-tocopherol level (P<0.001) but not in the concentrations of the other compounds (P>0.05). The finishing feeding promoted higher mean concentrations of anserine and creatine but lower carnosine values (P>0.05) than directly slaughtered dry-off cows. The variation between muscles and from animal-to-animal makes it difficult to exactly define the antioxidant status of the dairy cow's meat.

Effect of fat content, casing type and smoking procedures on PAHs contents of Portuguese traditional dry fermented sausages.

Portuguese dry fermented sausages are traditionally processed through direct drying/smoking, making them susceptible to polycyclic aromatic hydrocarbons (PAHs) contamination. The purpose of this study was to assess the effect of added fat (20% and 40%), casing type (hog and collagen) and smoking procedures (direct and indirect exposure) on the 16 EPA priority PAHs in dry fermented sausages manufactured according traditional processing. The total PAHs content (sum of 16 PAHs) found in whole product (casing included) varied between 150 and 870 µg kg(-1), with more than 99% of this content corresponding to harmless low molecular weight compounds. Concerning benzo(a)pyrene (BaP) and PAH4, the respective maximum contents (0.32 and 10.35 µg kg(-1), respectively) did not exceed the imposed limits regulated by the European Union. According to our results, casing type was the most influential factor. For hog samples, fat content and smoking regime alone did not influenced the total PAHs amount. However, significantly higher (p<0.05) contamination levels were detected in hog casing samples combining high fat content and direct smoking procedures. In opposition, irrespective of the fat content and smoking regime, safer products, with significantly lower (p<0.001) contamination levels, were obtained when collagen casing was used.

Comparative survey of PAHs incidence in Portuguese traditional meat and blood sausages.

Sixteen polycyclic aromatic hydrocarbons (PAHs) in representative traditional sausages produced in "Trás-os-Montes" and "Alentejo", were determined. Light PAHs represented similar overall contents in both regions and showed close decreasing order patterns (ACY, PHE, FLR and NAP), irrespective of the product type considered. Amongst the carcinogenic/mutagenic PAHs analyzed (PAH8), both regions also had greater contents associated to BaA and CHR, with slightly higher values for the former compound in "Alentejo" and, oppositely, for the later in "Trás-os-Montes". However, their quantitative comparison showed that the general mean total PAH content found in "Trás-os-Montes" was almost 3-fold higher than in similar products from "Alentejo" and this factor was about 8-fold superior when the PAH8 and PAH4 indicators were compared, expressing benzo[a]pyrene toxic equivalencies (BaPE), 15 times (total mean toxicity), 34 times (PAH8) and 9 times (PAH4) higher. In general terms, the mean BaP content of all analyzed samples from "Alentejo" was 0.41 µg kg(-1). Differently that value in "Trás-os-Montes" reached 3.57 µg kg(-1), expressing concerning average contents of 5.35, 5.87 and 4.51 µg kg(-1) in Chouriço de Carne, Moura and Salpicão sausages, respectively.

Polycyclic aromatic hydrocarbons incidence in Portuguese traditional smoked meat products.

Meat and meat products safety is, nowadays, a priority quality requirement with chemical hazards having a great impact. Amongst the residues and contaminants, polycyclic aromatic hydrocarbons (PAHs) can be of particular concern, namely in those products having direct smoking during processing. In order to investigate the contamination levels in traditional dry fermented sausages manufactured in Alentejo (South of Portugal), 66 samples were collected from regional producers. PAH8 represented less than 0.5% of the total contamination profile, with benzo[a]anthracene and chrysene being the most concentrated compounds (maximum contents of 7.53 and 8.9 µgkg(-1)), irrespective of the product type analysed. Benzo[a]pyrene content varied between 0.21 and 1.00 µgkg(-1), with only one sample showing this maximum content. Blood sausages were potentially more risky, since total PAH8 contents were generally higher and because its presence in inner parts were significantly superior than that found in casings, comparatively to meat counterparts, which expressed superior benzo[a]pyrene toxic equivalents.

Influence of processing in the prevalence of polycyclic aromatic hydrocarbons in a Portuguese traditional meat product.

The concentration of 16 polycyclic aromatic hydrocarbons (PAHs) was determined in traditional dry/fermented sausage along distinct stages of processing under two different technological procedures (traditional and modified processes). The influence of product's position in the smoking room, on the variation of contaminants and in their migration dynamics from the outer into the inner part, was also followed up. Raw material mixtures presented expressive total PAH values, 106.17 µg kg(-1) in wet samples and 244.34 µg kg(-1) in dry mater (DM), expressing the frequent fire woods occurred in the regions pigs were extensively reared. Traditional processing produced a higher (p<0.01) total PAH levels comparatively to modified/industrial procedures, with mean values reaching 3237.10 and 1702.85 µg kg(-1) DM, respectively. Both, raw materials and final products, showed PAH profiles with light compounds representing about 99.0% of the total PAHs, mostly accounted by those having two rings (naphthalene-27.5%) or three rings (acenaphtene-16.9%; fluorene-27.1%; phenanthrene-19.5% and anthracene-3.9%). The benzo[a]pyrene (BaP) accumulated in traditional and modified processed products never surpassed the limit of 5 µg kg(-1) established by the EU legislation. PAHs in products hanged in bars closer to heating/smoking source speed up their transfer from the surface/outer portion to the inner part of the product.

Effect of processing on proteolysis and biogenic amines formation in a Portuguese traditional dry-fermented ripened sausage "Chouriço Grosso de Estremoz e Borba PGI".

The influence of alternative drying environmental conditions on the proteolysis of a traditional Portuguese fermented sausage was evaluated, in relation to different ripening periods. Traditional sausages (batch T) had lower pH than counterparts (batch M), with differences (P<0.05) focused at the fermentation stage. A remarkable accumulation of free amino acids (FAA) was detected in both batches along the ripening process, with batch T having higher mean levels than batch M (1795.2 mg 100 g(-1) DM vs. 1742 mg 100 g(-1) DM in S7, respectively), but with differences being significant for long ripened products. In both batches, glutamic acid became the most concentrated FAA in end products currently consumed (101.6 mg 100g(-1) DM and 111.0 mg 100g(-1) DM - S6; 233.8 mg 100g(-1) DM and 220.9 mg 100g(-1) DM - S7 from batches T and M, respectively) followed by leucine>alanine>taurine>serine>valine and taurine>alanine>leucine>serine>valine sequences in the former product from batches T and M, respectively, and, coincidently, the same sequence for both batches in the later (serine>leucine>alanine>proline>valine). Such effect on FAA concentrations led to a distinct (P<0.05) expression of sweet, bitter, acidic and aged sensorial attributes between batches, in S8 and S9 products. BA typical quantitative sequences varied between batches according to the ripening stage, with differences in S6 and S7 end products also reflecting the distinct microbial development rates and profiles observed. Overall, the total BA mean concentration was higher (P<0.05) in products from batch T.

Muscle fiber and fatty acid profiles of Mertolenga-PDO meat.

The influence of phenotype and muscle type on intramuscular total lipids (ITL) neutral lipid (NL) and phospholipid (PL) compositions, cholesterol, α-tocopherol and haem iron contents were evaluated in Semitendinosus (St), Longissimus dorsi (Ld) and Supraspinatus (Ss) muscles from 39 Mertolenga young bulls. The results showed that lipid, α-tocopherol, cholesterol and haemic iron contents were not influenced by phenotype. Furthermore, the individual effect of phenotype was not a significant source of variation on ITL, NL and PL fatty acid composition. Muscle histological traits from Unicolor phenotype (n=13) showed that Ss and Ld muscles exhibited higher proportion of type I (P<0.001) and oxidative fibers (P<0.001) and lower percentages of IIB fibers (P<0.001) than St. The Ss muscle, with higher relative area occupied by oxidative fibers (P<0.05-0.001) than Ld and St, had higher ITL (P<0.001), NL (P<0.001), PL (P<0.05-0.01), α-tocopherol (P<0.001), cholesterol (P<0.01) and haem iron (P<0.001) contents than its counterparts. Muscle type notably affected ITL, as a result of its influence on NL rather than in PL composition.

Proteolysis in Painho de Portalegre dry fermented sausage in relation to ripening time and salt content.

The effect of salt addition (3% and 6% in the final product) on the shelf-life related physicochemical characteristics and proteolysis profile during the ripening period of a Portuguese dry fermented sausage "Painho de Portalegre", were evaluated. The product with 6% salt concentration had low a(w) and pH values at most ripening periods evaluated, due to the influence of NaCl on the water binding capacity of the protein structure and to the low ammonia accumulation, respectively. Similar changes were observed for total basic volatile nitrogen (TBVN), free amino acid nitrogen (FAAN) and non-protein nitrogen (NPN) fractions in both products. After a clear increase during the first days of the processing phase, all the initial rates slowed down with some fluctuation in FAAN and NPN. In relation to small peptides and free amino acid accumulation, the major differences between the tested formulations were mainly observed on distinct profiles rather than on overall concentrations.

Influence of slaughter season and sex on fatty acid composition, cholesterol and α-tocopherol contents on different muscles of Barrosã-PDO veal.

The influence of slaughter season and sex on intramuscular total lipids (ITL) neutral lipid (NL) and phospholipid (PL) compositions, cholesterol and α-tocopherol contents were evaluated in Biceps femoris (Bf), Longissimus dorsi (Ld) and Supraspinatus (Ss) muscles from 92 Barrosã-PDO (Protected Denomination of Origin) calves. ITL content in Bf muscle was affected by slaughter season and sex whereas NL content was only affected by slaughter season. Neither sex nor slaughter season influenced cholesterol and α-tocopherol contents in the muscles under study. Concerning NL composition, sex was an important source of variation on the proportions of total SFA and MUFA in all muscles. Irrespective of the considered muscle, males had higher total SFA but lower total MUFA and MUFA/SFA contents than females. Slaughter season influenced C18:2 cis-9 trans-11 (CLA) content in Bf (P<0.01) and in Ss muscles (P<0.05) with calves slaughtered in autumn showing higher values than their counterparts. Total MUFA, n-3 PUFA and n-6/n-3 ratio contents in Ld muscle were also affected by slaughter season. Regarding PL composition, slaughter season×sex interaction affected total SFA, PUFA/SFA and n-6 PUFA contents in Bf and Ss muscles. In addition, this interaction influenced total MUFA (P<0.05) in Bf muscle and total PUFA (P<0.01) in Ss muscle. CLA content in PL from Ld was influenced by sex (P<0.05) and by slaughter season (P<0.01), with females slaughtered in autumn presenting the highest content. These results clearly indicate that sex and slaughter season are important factors that influence the fatty acid composition of Barrosã-PDO veal.

Incidence of different pork quality categories in a Portuguese slaughterhouse: A survey.

This study was designed to evaluate the incidence of the PSE/DFD status in a Portuguese pig slaughterhouse, covering two seasons of the year (spring and summer) in order to find out if the proportions of those poor meat quality categories were sufficient to concern the meat industry. Meat quality classification was based on the measurements of the pH(60), pH(24), drip losses and colour (L, a, b) in the longissimus dorsi muscle (between the last third and fourth ribs) of 380 pigs randomly chosen from the line. The high global incidence of PSE and likely PSE (30%) as well as DFD (10%) carcasses and the enormous variation of the meat quality between the different days of analysis proves that the pig population presents a great variation of halothane genotype and that handling procedures have to be optimized in order to decrease stress and glycogen store depletion. The percentage of PSE carcasses during the summer season was double that found in the spring, probably due to a higher environmental temperature and relative humidity.

Measurements of pH(60) in pork using ISFET/REFET and glass electrode methods.

pH values of 180 pork longissimus dorsi muscles were obtained using different measurement methods. A glass combined penetration electrode and an ISFET/REFET pH sensor system were used directly in the muscle, whereas in the homogenate, pH was assessed with a glass combined electrode. The results showed that no statistically significant differences were obtained between the methods in all tested samples. However, samples where pH(60) stood below 5·9, produced a better agreement between methods. Comparing the values obtained from the two direct puncture methods in the first group of samples (pH<5·9) the I/R probe appeared to agree with those obtained from the homogenates. While working, the ISFET/REFET system proved to be a good device to detect carcasses with fast post mortem pH decline. Nevertheless, the excessive time required display stabilisation prohibits its use for continuous measurements on high speed slaughter-lines.

Muscle pH(60), colour (L, a, b) and water-holding capacity and the influence of post-mortem meat temperature.

The use of the pH(60) and colour parameters (L, a, b) as chilled pork drip loss predictors 24 h post-mortem as well as the influence on this meat characteristic of an early blast cooling regime (90 min post-mortem) were investigated. Despite the best correlation found with pH(60) (-0·647), both indicators were found to be poor for this purpose, it being impossible to use them alone for pork quality classification (PSE/DFD status). Comparing the evolution between the drip losses on chilled and early deep frozen (-60°C) longissimus dorsi pork cuts, the results indicate that both the thawing regime and the time the samples stay in refrigeration, influence the observed trends significantly. The general drip loss enhancement seen after thawing as well as the increasing meat toughness, judged subjectively, must be due to cold-shortening and/or thaw rigor phenomena.