Effects of dietary olive and linseed oil on lipid composition, meat quality, sensory characteristics and muscle structure in pigs

Effects of Pig Dietary n-6/n-3 Polyunsaturated Fatty Acids Ratio and Gender on Carcass Traits, Fatty Acid Profiles, Nutritional Indices of Lipid Depots and Oxidative Stability of Meat in Medium-Heavy Pigs

The effects of different dietary n-6/n-3 polyunsaturated fatty acids (PUFA) ratios and gender on key carcass traits, as well as the nutritional and technological quality of lipids in medium-heavy pig tissues have been poorly studied. To investigate the subject, 24 Large White, barrows and gilts, evenly divided into two groups of 12, were fed from 80 kg of live-weight (LW) until slaughter at 150 kg LW, either a high (9.7:1) (HPR) or low (1.4:1) (LPR) dietary n-6/n-3 PUFA ratio. On individual samples of longissimus thoracis muscle (LTM), subcutaneous (SF) and perirenal (PF) adipose tissues (ATs), the fatty acid (FA) composition was determined by gas chromatography, and lipid nutritional indices (LNIs) were calculated. The oxidative stability of meat was evaluated by determining the malondialdehyde content on raw and cooked (24 h postmortem) and refrigerated (8 days postmortem) LTM samples. The carcass traits did not vary between genders and diets. The LPR group showed a higher n-3 PUFA level and a lower n-6/n-3 PUFA ratio in all the tissues examined and better LNI, especially in the ATs. Diet did not affect the oxidative stability of meat. Gender did not influence the n-6/n-3 PUFA ratio, while barrows showed improvements in some LNI in ATs. Reducing the n-6/n-3 ratio in the diet of growing-finishing medium-heavy pigs improved the FA profile in all tissues and most LNI in ATs without impairing the oxidative stability of meat.

Effect of feeding olive pomace acid oil on pork lipid composition, oxidative stability, colour, and sensory acceptance

One of the targets of the meat industry is to reduce production costs and to increase the sustainability of the food chain, which has driven the attention towards the use of by-products as feed ingredients. Acid oils are fat by-products coming from the chemical refining process of edible oils, with a high energy value and that are approved as feed ingredients in the European Union. However, meat producers are hesitant to utilise them due to their varying composition and the limited understanding of their impact on animal performance and meat quality. The objective of this study was to evaluate the effects of using olive pomace acid oil (OPAO) instead of its corresponding crude olive pomace oil (OPO) or crude palm oil (PO) in pig diets on lipid composition, lipid oxidation and quality of pork loin (longissimus dorsi), fresh and after commercial refrigerated storage for 8 days. The experimental design consisted of feeding pigs with four diets supplemented with a 5% of PO, OPO, OPAO or a blend (B) of PO and OPAO (50:50, w/w). Fresh and refrigerated pork loin samples were assessed for fatty acid profile; tocopherol (T) and tocotrienol (T3) composition; lipid oxidative stability with the ferrous oxidation-xylenol orange method; 2-thiobarbituric acid (TBA) value; volatile compounds; colour; and sensory acceptance. Results showed that refrigeration reduced the total T + T3 levels and increased the TBA values and the volatile compound concentrations. The refrigerated storage also affected the instrumental colour parameters (L*, a* and b*) but not the overall acceptance of pork. Regarding the diet, pork from OPAO diet showed a higher unsaturated-to-saturated fatty acid ratio than pork from PO and B diets. The lowest T + T3 concentration was found in OPO and OPAO fresh pork and in OPAO refrigerated pork. The oxidative stability of fresh pork was lower for OPAO than for PO diet, but no significant effect of the diet was observed for this parameter in refrigerated pork. The TBA values and volatile compound concentrations of fresh pork were not affected by the diet. After refrigeration, OPAO pork had the highest TBA value and volatile compound concentrations. In any case, colour and consumer acceptance of pork were not affected by diet. In conclusion, in order to upcycle acid oils in pig diets, and considering results on the lipid oxidative stability of pork, it would be preferable to add the OPAO used in this study blended with PO.

Effects of multiple vitamin E levels and two fat sources in diets for swine fed to heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations, immune capacity, and antioxidant capacity of plasma and tissue

The study objective was to evaluate the effect of two fat sources and graded levels of vitamin E (VE) supplementation on tissue fatty acid profile, VE concentrations, immune capacity, and antioxidant capacity of plasma and tissues of pigs at heavy slaughter weight (150 kg). A total of 48 individually-fed pigs (24 barrows, 24 gilts; 28.44 ± 2.69 kg) were randomly assigned to eight dietary treatments in a 2 × 4 factorial arrangement. The two fat treatments were either 5% tallow (TW) or 5% distiller's corn-oil (DCO). The VE treatments included four levels of α-tocopheryl-acetate (11, 40, 100, and 200 ppm). Compared to pigs fed the DCO diet, pigs fed the TW diet had greater SFA (C14, C16, and C18; P < 0.05) and MUFAs (C14:1, C16:1, C18:1, and C20:1; P < 0.05), lower PUFA (C18:2n-6, C18:3n-3, C20:2, C20:3, and C20:4; P < 0.05) and iodine value in the backfat and belly fat. Increasing dietary VE supplementation level increased α- and total tocopherol concentrations in plasma (linear and quadratic, P < 0.05), liver, and loin muscle (linear, P < 0.06), superoxide dismutase activity (quadratic, P < 0.05), but decreased γ-tocopherol concentrations in liver (linear, P = 0.06), plasma, and loin muscle (quadratic, P < 0.07), and decreased liver glutathione disulfide (GSSG; linear, P = 0.07) and malondialdehyde (MDA) content (quadratic, P < 0.05). There was an interaction between fat sources and dietary VE supplementation level on the concentration of α-tocopherol in the loin muscle (P < 0.05) wherein a greater increase was observed in the TW treatment than the DCO treatment with the increasing dietary VE supplementation level. In conclusion, dietary FA composition in TW and DCO affected the composition of most FA in backfat, belly fat, and liver while increasing VE supplementation level did not significantly alter the FA profile in these tissues. Increasing dietary VE supplementation level increased tocopherol concentrations in plasma, liver and loin muscle, and improved antioxidant capacity while tocopherol concentrations in plasma, liver and loin muscle in the TW treatment increased more than they did in the DCO treatment.

Effects of replacing soybean meal with linseed meal in broiler diet on selected broilers’ blood parameters, meat chemical composition, fatty acid profiles, and sensory characteristics

The study was conducted with the objective of determining the effects of the dietary replacement of soybean meal with graded levels of linseed meal on selected blood parameters, meat composition, fatty acid profiles, and meat quality of broiler chickens. Cobb500 broilers were fed diets containing linseed meal at 0% (T1), 6.5% (T2), 13% (T3), 19.5 (T4), and 26% (T5), replacing 0% to 100% soybean meal in compound rations for 45 days. The experiment was conducted using a completely randomized design with five treatments, each replicated three times with 12 birds. Blood hematological indices were not affected (P&gt;0.05) by treatment diets while among the blood biochemistry triglyceride and cholesterol concentrations in T1 were higher (P&lt;0.05) than in T3, T4, and T5. Glucose was higher in T3, T4, and T5 than in T1 and T2 (P&lt;0.01). The breast and thigh proximate composition for crude protein (CP), ether extract (EE), ash, carbohydrate, and gross energy were similar (P&gt;0.05) among treatments. The sensory scores for breast and thigh meat samples were not different (P&gt;0.05) among treatments. The palmitic acid content of breast and thigh meat was higher (P&lt;0.05) in T1 and T2 than in the other treatments. Eliadic and stearic acid concentrations in thigh meat were greater (P&lt;0.05) in T1, T2, and T3 than in T4 and T5. The oleic and linoleic acid contents of thigh meat were higher (P&lt;0.05) in T2 and T3 than in the rest of the treatments. Breast linolenic acid was high (P&lt;0.05) in T5 but similar in thigh meat. Total saturated fatty acid (SFA) showed a decreasing trend with an increasing level of linseed meal (LSM) in the ration. The ratio of monounsaturated fatty acid (MUFA) to SFA for breast and thigh was higher in T4 and T5 than in T1 and T2. Breast meat ratio of omega-6 (n-6) to omega-3 (n-3) showed a decreasing trend as the level of LSM replacement for soybean meal (SBM) in the ration increased. Generally, linseed meal replacement levels up to 26% in the broilers’ diet improves the essential fatty acid content of chicken meat without affecting the proximate composition and the chickens’ normal blood indices and does not alter meat sensory attributes.

Maternal Supplementation with Polyphenols and Omega-3 Fatty Acids during Pregnancy: Prenatal Effects on Fetal Fatty Acid Composition in the Iberian Pig

Simple Summary

The present study aimed to determine the effects of maternal dietary supplementation combining hydroxytyrosol and n3 polyunsaturated fatty acids (n3-PUFA) from day 35 to day 100 of gestation on the fatty acid (FA) composition of the offspring tissues of the Iberian pig. No effects were found in the plasma FA composition of the dams but higher levels of n3-PUFA were found in the plasma and different tissues (muscle, liver, and brain) of the supplemented fetuses. These findings may have important implications for piglets’ health and may offer guidance for achieving human dietary n3-PUFA recommendations.

Abstract

Intrauterine Growth Restriction (IUGR) is a major problem in pig production and different strategies, mainly maternal supplementation with different agents, are currently being studied. The combination of hydroxytyrosol and n3-PUFA seems to be a promising treatment to counteract IUGR, since the combination may help improve n3-PUFA composition and lower the inflammatory status of IUGR piglets. The aim of the present study is to determine the effects of a maternal supplementation, from day 35 to day 100 of pregnancy, with linseed oil and hydroxytyrosol on the fetal FA composition. The results showed higher n3 levels, including eicosapentaenoic and docosahexaenoic FA in the offspring from treated gilts, which showed lower n6-PUFA/n3-PUFA (n6/n3) ratios. Saturated and monounsaturated fatty acids were also affected by treatment, especially in the muscle and brain. Thus, a maternal supplementation with linseed oil and hydroxytyrosol affected the fetal FA tissue composition, which could have implications in pig production due to the improvement of the piglets’ health status.

Can the Introduction of Different Olive Cakes Affect the Carcass, Meat and Fat Quality of Bísaro Pork?

The present study aimed to evaluate the effect of the inclusion of different olive cakes in the diet of Bísaro pigs on the carcass, meat and fat. The carcasses of 40 animals fed a diet with five treatments (T1—Basic diet and commercial feed; T2—Basic diet + 10% crude olive cake; T3—Basic diet + 10% olive cake, two phases; T4—Basic diet + 10% exhausted olive cake; T5—Basic diet + 10% exhausted olive cake + 1% olive oil) were used to study the effect on carcass traits, physicochemical meat quality and lipid composition of meat and backfat. There were no significant differences between treatments for the conformation measurements performed, except for the length at the seventh and last rib (p < 0.05). The percentage of prime cuts of the carcass in Bísaro pig is within the values indicated by the Portuguese Standard 2931. No significant differences between treatments for body weight, pH and carcass weight were found. The values of ultimate pH (5.7), L* (51−52), b* (11−12) and SF (3.4−4.2) observed confirm a non-exudative and firm meat without quality deviations, such as DFD or PSE. Thus, as a general conclusion, the inclusion of different olive cakes in the diet of Bísaro pigs did not cause any negative consequences on the carcass characteristics and conformation as well as in the meat and lipidic quality. In addition, the inclusion of this olive industry by-product in the animal diet would be an important contribution to solving the problem of the great environmental impact from olive-mill wastewaters from the extractive industries.

Effects of dietary vitamin E and fat supplementation in growing-finishing swine fed to a heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations and antioxidant capacity of plasma and tissue

The study aimed to assess the effects of vitamin E (VE) supplementation and fat source on fatty acid (FA) composition, VE concentrations, and antioxidant capacity in plasma and tissues of pigs fed to a heavy slaughter weight (150 kg). A total of 64 pigs (32 barrows, 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement. Fat sources included corn starch (CS), 5% tallow (TW), 5% distiller’s corn oil (DCO), and 5% coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Five-phase diets were formulated to meet requirement estimates of NRC (2012) and fed to pigs for each period of 25 kg from 25 to 150 kg. Increasing VE supplementation level increased C16:1 (P < 0.05) content but decreased C20:0 (P < 0.05) content in backfat and belly fat, while in liver, it increased C17:0 (P < 0.05) but decreased C18:0 (P < 0.05). Compared to the pigs fed the CS diet, the pigs fed the CN diet had greater (P < 0.05) content of total saturated FA, the pigs fed the DCO diet had greater (P < 0.05) content of total polyunsaturated FA content and iodine value, and the pigs fed the TW diet had greater (P < 0.05) content of total monounsaturated FA in backfat, belly fat, and liver. Plasma VE concentrations increased linearly (P < 0.05) with increasing length of feeding but faster (P < 0.05) in the pigs fed the CN and TW diets compared with the CS and DCO diets within the 200 ppm VE level; the pigs fed the DCO diet had the highest plasma VE concentrations (P < 0.05) from Phase 2 to Phase 5 within the 11 ppm VE level. The VE concentrations in liver and loin muscle (P < 0.05) increased with increasing dietary VE level from 11 to 200 ppm, but it was not affected by dietary fat source. There was no effect of VE supplementation and fat source on antioxidant capacity in plasma and liver except that pigs fed the DCO diet had greater liver SOD activity (P < 0.05) than the pigs fed the CN diet. In conclusion, dietary VE supplementation did not affect FA profile in backfat, belly fat, and liver consistently, while dietary FA composition with different fat sources affected much of the FA profile in backfat, belly fat, and liver. The higher level of VE supplementation increased liver and muscle VE concentrations and dietary fat sources affected plasma VE concentrations differently (P < 0.05), wherein the TW and CN diets increased the VE absorption greater than the DCO diet.

Effect of Concentration of Flaxseed (Linum usitatissimum) and Duration of Administration on Fatty Acid Profile, and Oxidative Stability of Pork Meat

Flaxseed is a common ingredient used for livestock feed. The aim of this work was to study the effect of a diet supplemented with flaxseed at 5% and 10% concentrations in the intervals of 3 and 6 weeks prior slaughter on fatty acid profile and oxidative stability of pork meat. Meat samples were collected after slaughter from each animal (five groups, n = 6). Samples of the musculus longissimus dorsi (MLD) and the musculus gluteobiceps (MGB) were selected. Chemical composition, fatty acid profile and oxidative stability during the storage of meat under chilling conditions (4 °C, 7 days) was analyzed. The addition of flaxseed significantly affected the composition of fatty acid profile and the shelf life of the produced meat. The fat content was changed in the experimental groups with 10% flaxseed supplementation (10.84% in MGB and 9.56% MLD) versus the control group. Despite the different concentrations of flaxseed, the best EPA/AA ratio was observed in the experimental groups fed with flaxseed supplementation for 3 weeks. The worst oxidative stability of meat samples (p < 0.05) was recorded in the experimental groups with the addition of flaxseed for 6 weeks, which was related to higher PUFA content in samples of the experimental groups and higher susceptibility of PUFAs to lipid oxidation. The oxidative stability of meat in the experimental group fed 5% flaxseed supplementation for 3 weeks was not affected.

The Effect of the Season, the Maintenance System and the Addition of Polyunsaturated Fatty Acids on Selected Biological and Physicochemical Features of Rabbit Fur

Simple Summary

Rabbit furs are a valuable material used in the fur industry. Many studies show beneficial effects of omega-3 acids supplementation on the skin and coat of animals. The aim of the study was to show the impact of environmental conditions and dietary supplementation with ethyl esters of linseed oil on the quality of the rabbit hair coat. The experiment was carried out in four stages: laboratory (summer and winter) and outdoor (summer and winter). The experimental rabbits were given an addition of ethyl linseed oil to their feed (during 2 months). To assess biological and physico-mechanical properties of the coat samples and to determine fatty acid profile and histological evaluation, the hair samples were collected three times: before the study, after two months of treatment, and after two months from the end of supplementation. The obtained results show that the environmental conditions have a major impact on the quality of the rabbit coat. The best results of hair heat protection were obtained from animals kept outdoors. Administration of linseed oil ethyl esters had a positive effect on the hair fatty acid profile.

Abstract

The aim of the study was to show the impact of environmental conditions and dietary supplementation with ethyl esters of linseed oil on the quality of the rabbit hair coat. The research was divided into 4 stages: laboratory (summer and winter) and outdoor (summer and winter). In each stage of the research, animals were divided into control and experimental groups. The animals were fed in accordance with the feeding standards of reproductive rabbits during the period of sexual dormancy. The rabbits from the experimental groups during the first two months were given an addition of ethyl linseed oil to the feed. In the experiment, linseed oil was cold-pressed directly in the laboratory. Three samples of hair were collected: before the study, after two months of treatment, and after two months from the end of supplementation. The hair coat biological properties, such as share of individual hair fractions (%), heat transfer index (HTI), hair diameter (μm), as well as physico-mechanical properties such as breaking force (N), breaking stress (kg/cm²) and elongation (%) were performed. Moreover, the histological structure of hair and histological hair evaluation were performed. The fatty acid profile was determined in the hair as well. The obtained results of the content of individual fatty acids were grouped into saturated fatty acids and unsaturated fatty acids. In addition, omega-3 and omega-6 were distinguished from the group of unsaturated acids. The environmental conditions have a major impact on the quality of the rabbit coat. The best results of hair thickness and their heat protection were obtained from animals kept outdoors. The studies did not show an influence of the administered preparation on the quality of the rabbit coat. The hair became thinner, but more flexible and tear-resistant. Administration of linseed oil ethyl esters had significant, beneficial changes in the fatty acid profile in hair and hair sebum were observed. There was a significant increase in omega-3 acids, and a significant decrease in the ratio of omega-6 to omega-3 acids.

Effects of Dietary Perilla Cake Supplementation in Growing Pig on Productive Performance, Meat Quality, and Fatty Acid Profiles

The objective of this study was to determine the effect of perilla cake (PC) supplementation in a growing pig diet on overall growing performance, meat quality, and fatty acid profile. A total of 24 barrow grower crossbred pigs (Large White × Landrace) × Duroc with an initial average body weight of 26.33 kg were fed with a basal diet supplemented with PC at 0%, 5%, and 10% in (PC0, PC5, and PC10, respectively) for 12 weeks. At the end of the experimental period, pigs were slaughtered to determine carcass traits and meat quality. Back fat, abdominal fat, and longissimus dorsi (LD) muscle were collected to investigate fatty acid composition. The results show that the average daily gain (ADG) in the PC10 significantly increased. However, PC supplementation did not influence carcass traits and meat quality except the color as described by lightness (L*). Dietary PC supplementation significantly increased the α-linolenic acid (ALA, C18:3 cis-9, 12, 15), whereas n6/n3 ratio decreased significantly in all tissues investigated. Thus, it can be concluded that the supplementation of PC in growing pig diet is a potential way to increase the fatty acid composition to that required for healthier meat.

Use of Mediterranean By-Products to Produce Entire Male Large White Pig: Meat and Fat Quality

Simple Summary

Sustainability is a current issue that is gaining an important place in consumer choices. Natural and environment-friendly products are becoming more popular and widely accepted, so changes to production methods are needed. Local by-products offer a good way to close the circle on animal production. In this study, two by-products were used: Garlicon ST^®, a supplement obtained from garlic and onion, which could improve the microbiota gut and the ingestion in pigs, and olive pulp from Mediterranean oil production, which could be a good source of nutrients for pigs. The impact of the use of both by-products on the quality of meat and fat of pigs was examined.

Abstract

A total of 70 male growing non-castrated pigs (Large White), with a 23.07 ± 2.87 kg average body weight (BW), were randomly allocated to three treatments in a 103 day trial: a CONTROL diet and two experimental diets, ALLIUM (5 g/kg of Allium spp. extract) and OLIVE (100 g/kg of olive pulp). Animals were slaughtered at 115 kg live body weight. Meat and fat quality were analyzed. Animals fed ALLIUM and OLIVE had higher water holding capacity (WHC) than those fed the control diet. No significant differences were observed between groups for cooking loss, drip losses and color CIELab. No antioxidant effect was observed on an oxygen radical absorbance capacity (ORAC) test. Animals fed OLIVE presented a more unsaturated fatty acid profile than CONTROL and ALLIUM. Meat from ALLIUM group and OLIVE showed her values of brightness and meat odor than CONTROL. Mean scores of sensory analyses (color, odor, flavor and juiciness) of cooked samples were similar for the three treatments, with the meat samples from the ALLIUM and OLIVE treatments being less hard. Consumers did not reflect a preference for any of the treatments. Both by-products could be used for pork production.

Changes in carcass traits, meat quality, muscle fiber characteristics, and liver function of finishing pigs fed high level of fish oil

The study was aimed to investigate the changes in carcass traits, meat quality, muscle fiber characteristics, and liver function in pigs fed with high levels of fresh fish oil and oxidized fish oil. About 30 piglets were randomly assigned to receive basal diet plus 2% fish oil (LFO), basal diet plus 8% fish oil (HFO), or basal diet plus 8% oxidized fish oil (OFO) for 120 d. Pigs of the HFO and OFO group showed reduced carcass weight, dressing percentage, loin eye area, and increased yellowness of the longissimus dorsi muscle compared with LFO group (P < 0.05). Dietary HFO and OFO suppressed the relative expression levels of myosin heavy chain (MyHC) isoform (I and II a), glutathione peroxidase 4, and NAD(P)H: quinone oxidoreductase-1 and mitochondrial biogenesis in longissimus dorsi muscle (P < 0.05). Dietary HFO or OFO increased the serum aspartates aminotransferase, alanine aminotransferase, total bilirubin, direct bilirubin, oxidized low-density lipoprotein, liver index, and concentration of malondialdehyde (MDA) in liver (P < 0.05). In conclusion, high levels of fresh fish oil and oxidized fish oil have adverse effects on carcass traits, muscle fiber characteristics, and liver function, which may be partly due to the mitochondrial dysfunction and impaired antioxidative capacity.

Plant Feed Additives as Natural Alternatives to the Use of Synthetic Antioxidant Vitamins in Livestock Animal Products Yield, Quality, and Oxidative Status: A Review

The interest for safe and natural foods of animal origin is currently increasing the use of plant feed additives (PFA) as antioxidants in animal nutrition. However, studies with livestock animals dealing with PFA as antioxidants are scarce. The aim of the present review was to evaluate the antioxidant impact of PFA compared with synthetic vitamins on animal food product yield and quality. For this purpose, peer-reviewed studies published between 2000 and 2020 were collected. Most papers were carried out on ruminants (n = 13), but PFA were also tested in swine (n = 6) and rabbits (n = 2). The inclusion of PFA in the diets of pigs, rabbits, and ruminants improved the products’ quality (including organoleptic characteristics and fatty acids profile), oxidative stability, and shelf life, with some impacts also on their yields. The effects of PFA are diverse but often comparable to those of the synthetic antioxidant vitamin E, suggesting their potential as an alternative to this vitamin within the diet.

Quality and Shelf Life of Fresh Meat from Iberian Pigs as Affected by a New Form of Presentation of Oleic Acid and an Organic-Acid Mix in the Diet

The objective of the study was to evaluate the inclusion of a novel form of oleic acid and an organic-acid mix in the diet of Iberian pigs, and their effect on the quality and shelf-life of the pig meat. 200 castrated male Iberian pigs were randomly assigned to four groups. Diets included different fat sources: pig fat (G1), solid oleic acid (G2), oleic-high sunflower oil with solid oleic (G3); a diet of G3 supplemented with organic-acid mix (G4). Pigs were slaughtered at 182 days. Back fat and the longissimus thoracis et lumborum muscles were removed, and nutritive and sensory quality were analyzed. The shelf-life of meat packaged (70%O₂/30CO₂) during retail storage up to 21 days were studied. A higher percentage of oleic acid and MUFA, and lower SFA were observed in subcutaneous fat on a G2 diet. G2 resulted in the highest muscle fat content, and G4, the highest cooking losses. In sensory analysis, marbling, tenderness and chewiness were higher in the G2 samples. No differences were found in the bacterial count and sensorial analysis depending on storage time at the end of the experiment, but a lower total viable count was showed at the start of the study in the G4 samples. These results suggest a better assimilation of solid oleic acid. However, the organic-acid mix requires further studies.

The Effect of Replacement of Soybean Meal with Corn Dried Distillers Grains with Solubles (cDDGS) and Differentiation of Dietary Fat Sources on Pig Meat Quality and Fatty Acid Profile

Simple Summary

The growing demand for protein and the reluctance of consumers to use genetically modified feeds necessitate the use of other protein feeds. Corn dried distillers grains with solubles (cDDGS) is a well-digested protein feed; however, it is rich in unsaturated fatty acids and can negatively affect the meat quality and oxidative stability. The negative influence of dietary unsaturated fatty acids on meat quality can be balanced by feed additives, e.g., a dietary saturated fat source increasing the iodine value of fat. To reduce the detrimental effect of corn DDGS in the present experiment, the beef tallow and coconut oil in a feed mixture were studied, as both of them are more saturated than corn DDGS and rapeseed oil. The aim of the study was to investigate mixtures comprising corn DDGS as a partial replacer for soybean meal as well as different dietary saturated fat sources to determine their effect on the meat quality and fatty acid profile. The relationships between dietary fatty acid profile and meat fatty acid profile and between various meat quality parameters were analyzed.

Abstract

The aim of the study was to investigate mixtures comprising corn distillers dried grain with solubles as a partial replacer for soybean meal (SBM) and different dietary fat sources, in order to determine their effect on the meat quality and fatty acid profile. Thirty-two crossbred fatteners were divided into four groups: I–SBM + rapeseed oil, II–cDDGS + rapeseed oil, III–cDDGS + beef tallow, IV–cDDGS + coconut oil. The experiment took place from 60 to 118 kg. At the end of fattening, all pigs were slaughtered and samples of meat (musculuslongissimus lumborum) were taken. The fatty acid profile, texture, and quality traits were analyzed. Corn DDGS affected drip loss. Beef tallow and coconut oil improved water holding capacity and drip loss and increased fat content, compared to the control group. The dietary fat type affected the fatty acid composition, iodine value, and consequently some quality traits of meat. However, these relationships varied. Fat content in the meat was inversely correlated with shear force and texture parameters, but positively with tenderness and juiciness. The fatty acid profile significantly influenced cohesiveness, chewiness, resilience and sensory traits, which were the most beneficial in meat with higher fat content and higher fat saturation index.

Feeding a high oleic acid (C18:1) diet improves pleasing flavor attributes in pork

One of the main drivers in consumer meat choice is flavor with some pleasing flavor attributes associated with high oleic acid (C18:1) content in the intramuscular fat. This project aimed to produce pork with a distinctively pleasant bouquet by feeding C18:1 rich macadamia oil compared to corn oil. The project also tested three feed formulations based on cereals and pulses representing different pork producing areas: corn/soy (CS), sorghum-lupins (SL), or wheat/canola (WC). Compared to corn oil, feeding macadamia oil resulted in a significant increase in the C18:1 content in pork loin (longissimus dorsi) with the CS showing a higher impact than the WC diets. Pork loins from the two CS-based groups (CS-Corn and CS-Macadamia) were selected for a consumer sensory study involving 82 panelists (39 of Chinese background). Across ethnic backgrounds the taste of high C18:1 pork resulted in the highest hedonic values.

Fish Oil Microcapsules as Omega-3 Enrichment Strategy: Changes in Volatile Compounds of Meat Products during Storage and Cooking

This work aims to analyze the effects of processing and storage on the volatile compound profile of different meat products enriched in ω-3 polyunsaturated fatty acids (PUFA). Monolayered (Mo) and multilayered (Mu) microcapsules of fish oil were tested. The profiles of volatile compounds were analyzed by solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The enrichment with Mo significantly increases the abundance of volatile compounds from lipid oxidation and markers of ω-3 PUFA oxidation, which may be related to the multilayer structure of chitosan–maltodextrin in Mu that achieves greater fish oil protection than the simple coating of maltodextrin in Mo. Besides, the changes in volatile compounds during storage depends on the type of fish oil microcapsules and the meat products, having an increased abundance of ω-3 PUFA oxidation markers in dry-cured sausages added with Mo. However, the enrichment of these meat products with Mo and Mu does not modify the usual variations in the volatile compound profile during culinary cooking. Thus, the addition of multilayer fish oil microcapsules may be a suitable option for enrichment of meat products in ω-3 PUFA without modifying the abundance of volatile compounds, including oxidation markers.

Dietary Effects of Extra Virgin Olive Oil Extracted by Ultrasound Technology or Refined Olive Oil on the Quality Traits of Pork and "Capocollo di Martina Franca" Dry-Cured Meat

The "Capocollo di Martina Franca" is a traditional dry-cured pig meat product made in Apulia. The dietary fat source is able to influence the lipid profile of muscle and subcutaneous fat in pork, thus affecting its nutritional and sensorial quality as well as its suitability for technological processing. The aim of the study was to evaluate the effect of a diet containing extra virgin olive oil (EVOO, 3%, as-fed basis) extracted by ultrasound technology in comparison to refined olive oil (ROO, 3%, as-fed basis) on the quality of pig meat (longissimus lumborum muscle) and capocollo in relation to its storage time after seasoning (t1 = 0 vs. t2 = +6 months). The EVOO diet lowered the concentration of myristic, palmitic, stearic and total saturated fatty acids (SFA) and increased oleic, linoleic, total monounsaturated (MUFAs), polyunsaturated (PUFAs) and n-3 and n-6 fatty acids in pig meat; moreover, the atherogenicity and thrombogenicity indices were lowered, with potential benefits for human health. The overall quality of capocollo was positively affected by the EVOO diet, although storage for 6 months after ripening levelled the protective effects of extra virgin olive oil in comparison with refined olive oil.

Effect of Omega-3 Microcapsules Addition on the Profile of Volatile Compounds in Enriched Dry-Cured and Cooked Sausages

The main goal of the present study was evaluating the effect of enriching meat products (cooked (C-SAU) and dry-cured sausages (D-SAU)) with monolayered (Mo) and multilayered (Mu) fish oil microcapsules on the profile of volatile compounds, with special interest in lipid oxidation markers. For that, Solid-Phase Microextraction (SPME) and Gas Chromatography-Mass Spectrometry (GC-MS) were used. Significant differences were found in the volatile compound profile between Mo and Mu, which was been reflected in the meat samples. Thus, in general, volatile compounds from lipid oxidation have shown higher abundance in Mo and C-SAU and D-SAU enriched with this type of microcapsule, indicating that the wall of Mu (chitosan-maltodextrine) might protect the encapsulated bioactive compounds more effectively than that of Mo (maltodextrine). However, this finding is not reflected in the results of previous studies evaluating the sensory perception and oxidation stability of C-SAU and D-SAU, but it should be considered since unhealthy oxidation products can be formed in the enriched meat products with Mo. Thus, the addition of Mu as an omega-3 vehicle for enriching meat products may be indicated.

Low Dietary n-6/n-3 PUFA Ratio Regulates Meat Quality, Reduces Triglyceride Content, and Improves Fatty Acid Composition of Meat in Heigai Pigs

The objective of this study was to investigate the effects of dietary supplementation with different n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on growth performance, meat quality, and fatty acid profile in Heigai pigs. A total of 54 Heigai finishing pigs (body weight: 71.59 ± 2.16 kg) were randomly divided into three treatments with six replications (three pigs per replication) and fed diets containing different n-6/n-3 PUFA ratios: 8:1, 5:1, and 3:1. Pigs fed the dietary n-6/n-3 PUFA ratio of 8:1 had the highest feed to gain ratio (p < 0.01), carcass weight (p < 0.05), redness a* (p < 0.01), and yellowness b* (p < 0.01). Fatty acid compositions in longissimus dorsi muscle (LDM) and subcutaneous adipose tissue (SAT) were significantly changed (p < 0.01). Notably, the meat from the pigs fed with the low dietary n-6/n-3 PUFA ratio had higher n-3 PUFA contents (p < 0.01) and lower n-6/n-3 PUFA ratio (p < 0.01). The triglyceride and total cholesterol contents were significantly decreased in SAT from the pigs fed with dietary n-6/n-3 PUFA ratios of 5:1 (p < 0.05) and 3:1 (p < 0.01). Reducing n-6/n-3 PUFA ratio upregulated the expression of HSL (p < 0.05), CPT1 (p < 0.01), and FABP4 (p < 0.01) but downregulated ATGL (p < 0.01) expression. These results demonstrate that the lower n-6/n-3 PUFA ratio regulates meat quality and enhances the deposition of n-3 PUFA in Heigai pigs.

Enrichment diets of pigs with oil blends and its effects on performance, carcass characteristics and fatty acid profile

ABSTRACT The addition of different oil blends in the feed of finishing pigs was evaluated. Twenty-four castrated male finishing pigs were used in a randomized block design containing four treatments and six replicates. The treatments consisted of: Reference ration (RR) - 100% soybean oil feed; and the combination of the different oils: Blend1 - 50.0% soybean oil (SO), 25.0% flaxseed oil (FO), 12.5% olive oil (OO) and 12.5% canola oil (CO); Blend2 - 25.0% SO, 50.0% FO, 12.5% OO and 12.5% CO; and Blend3 - 25.0% SO, 12.5% FO, 12.5% OO and 50.0% CO. The performance, quantitative and qualitative carcass parameters, fatty acids profile and economic feasibility of the diets were evaluated. The use of blends in the diets did not influence the performance or carcass quality, but increased marbling and carcass yield. The fatty acid profile of the loin presented greater amounts of stearic acid in Blend3 and higher percentage of unsaturated fatty acids in animals fed with Blend1. The fatty tissue presented greater amounts of myristic acid in Blend1 and oleic acid in Blend3. The reference ration was the most economic. The Blends did not affect performance or carcass characteristics and improved the fatty acid profile.

In Vivo Performances, Carcass Traits, and Meat Quality of Pigs Fed Olive Cake Processing Waste

Simple Summary

In the recent years, the use of agro-industrial by-products in animal feed has been considered to reduce costs coming from the disposing of processing wastes and from the feeding for the animal breeding. The aim of this study was to assess the inclusion of two different levels of olive cake in 72 Pietrain pigs, during the finishing period; animals fed three dietary treatments contained increasing levels of olive cake: 0% (Ctrl), 5% (Low), and 10% (High) as partial substitution of wheat middling and soybean oil. Our hypothesis was that the inclusion of olive cake could be a possible strategy for the following: (i) finding unconventional ingredients of a commercial complete feed, and (ii) improving in vivo and postmortem performances, with particular attention on the acidic profile. The present study demonstrated that feeding olive cake improved animal performances and influenced some qualitative parameters, reducing the deposition of intramuscular fat and modifying the fatty acid composition in the intramuscular fat and backfat, where the concentration of MUFA and PUFA were increased and the quality indices (AI and IT) were improved. Obviously, the inclusion of unconventional ingredients in animal feed should not negatively affect the meat organoleptic characteristics.

Abstract

The aim of the study was to assess the inclusion of different levels of olive cake in pigs’ diet as a strategy to replace conventional ingredients and to improve meat quality traits. Seventy-two Pietrain pigs, during the growing–finishing period (50–120 kg BW), were fed with three dietary treatments that contained or did not contain olive cake: 0% (Ctrl), 5% (Low), and 10% (High). The trial lasted 90 days. Weekly, individual body weight (BW) and feed intake (FI) were recorded to calculate average daily gain (ADG) and feed conversion ratio (FCR). At slaughter, the dressing percentage was calculated and carcass weight and backfat thickness were measured. On a section of Longissimus thoracis muscle (LT), pH, color, chemical, and fatty acid composition were determined. Fatty acid profile was also determined in backfat. The statistical model included the effects of diet (Ctrl, Low, and High). The inclusion of 5% of olive cake in the diet improved significantly (p < 0.05) BW and FCR. Both levels of inclusion (5% and 10%) significantly reduced (p < 0.05) backfat thickness and intramuscular fat and modified their fatty acid composition, increasing (p < 0.05) the concentration of MUFA and PUFA and improving (p < 0.05) quality indices. Results suggest that olive cake did not negatively affect the productive performances.

Evaluating the use of fish oil microcapsules as omega-3 vehicle in cooked and dry-cured sausages as affected by their processing, storage and cooking

This work evaluated the use of monolayered (Mo) and multilayered (Mu) fish oil microcapsules as vehicles of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in cooked and dry-cured meat products as affected by the storage and culinary heating or dry-cured processing. Proximate composition, oxidation, EPA and DHA quantity, acceptability and morphology were evaluated. Mo and Mu microcapsules increased the quantity of EPA and DHA, leading to cooked and dry-cured products susceptible to be labeled as "source of omega-3 fatty acids", without influencing physico-chemical characteristics, oxidative stability, acceptability or usual changes that take place during the culinary heating or dry-cured processing. The storage at refrigeration influenced on usual modifications on lipid oxidation and hedonic scores, but overall quality of the meat products enriched seems not to be impaired after storing. Thus, it could be indicated the viability of Mo and Mu as vehicles to enrich meat products subjected to low and high temperature for manufacturing, storage at refrigeration and culinary heating.

The effect of salting time and sex on chemical and textural properties of dry cured ham

Effect of reduced salting and pig sex on the quality of Slovenian dry-cured ham Kraški pršut was studied. A total of 48 hams from 24 crossbred pigs (12 gilts, 12 castrates) were submitted to two different salting regimes; standard salting for 18 days (HS hams, n = 24) and shortened salting (LS hams, n = 24) for 10 days. Reduced salting time effectively reduced salt content but resulted also in higher extent of proteolysis of LS hams which was associated with differences in texture and colour of biceps femoris muscle. Lower fat oxidative stability was observed in HS hams. With regard to sex effect, the hams originating from gilts were more proteolysed which was associated with differences in texture and colour. Lipid oxidation was similar in gilts and castrates.

Current feeding strategies to improve pork intramuscular fat content and its nutritional quality

Pork, one of the most consumed meats worldwide, has been facing major challenges regarding its low sensory quality and unhealthy image of fat. This chapter addresses current feeding strategies to ameliorate pork sensory attributes and nutritional quality by increasing intramuscular fat deposition and improving fatty acid composition, respectively. Dietary protein reduction, alone or combined with some components, contributes to satisfy consumer requirements and enhances the competitiveness of the meat industry with higher pork quality and lower production costs. In addition, feeding sources of n-3 polyunsaturated fatty acids to pigs, mainly from marine origin (rich in eicosapentaenoic and docosahexaenoic acids), increases their content in pork, thus improving the health value of its fatty acid profile. In the near future, the inclusion of microalgae and seaweeds in feed represents a promising approach for the maintenance and development of the livestock sector, as an environmental friendly alternative to balance food and feed industries.

Effect of Soybean or Linseed Oil With RRR-D-α-Tocopherol or Dl-α-Tocopherol Acetate on Quality Characteristics and Fatty Acid Profile of Turkey Meat

In this study, the effect of the halved dosage of RRR-d-α-tocopherol (with respect to dl-α-to-copherol acetate) in diets containing oil rich in linoleic or α-linolenic acid (soybean or linseed oil, respectively) on the quality characteristics and fatty acid (FA) profile of turkey meat was studied. The experiment was conducted using 480 one-week-old turkey hens Big 6 line reared until the 16th week of life. The hens in Groups I and II received soybean oil added to their feed mixture, in Groups III and IV linseed oil was the source of supplementary fat. Turkeys in Groups I and III received dl-α-tocopherol acetate, whereas those in Groups II and IV RRR-d-α-tocopherol. No influence of dietary manipulation was observed on the chemical composition of turkey meat. The combined effect of the type of dietary fat and vitamin E source added to the feed was assessed using the color parameters. The addition of natural vitamin E to the feed mixture with linseed oil significantly increased the proportion of PUFA in breast muscle lipids compared with the group receiving soybean oil with this form of vitamin E. The inclusion of linseed oil increased the content of α-linolenic acid and total n-3 FA concentration in both muscles, compared with the diet that contained soybean oil. This modification of FA composition led to lower n-6/n-3 ratio in both the breast and thigh muscles regardless of the dietary vitamin E source. The use of natural form of tocopherol in diets containing linseed oil may help to improve the nutritional quality of turkey meat, especially by enhancing n-3 PUFA levels with no detrimental effect of lipid addition on the chemical composition and quality of meat.

Carcass yields, muscle amino acid and fatty acid profiles, and antioxidant indices of broilers supplemented with synbiotic and/or organic acids

The objective of the current research was to explore the possible impacts of dietary supplementation with synbiotic and/or organic acids (OA) on the performance traits, carcass yields and muscle amino acid and fatty acid (FA) profiles of broilers. Randomly, a total of 160 day-old chicks (Ross 308) were assigned into four equal groups (40 birds each), with each group subdivided into eight replicates (five birds/pen). The control group (CON) fed the basal diet with no supplements, while diets of the treated groups were supplemented with OA (Sodium butyrate 40%; 1 g/kg), synbiotic (comprised Bacillus subtilis, Saccharomyces cerivisiae, Streptococcus faecium, Mannan-Oligosaccharides and β-Glucan; 1 g/kg) and equal mix of OA and synbiotic (2 g/kg). Broilers fed the diets supplemented with synbiotic or synbiotic plus OA produced a significantly higher feed utilization efficiency (p = 0.021) and carcass yields (p = 0.038) than the CON and OA-supplemented groups. The group fed the diet supplemented with the synbiotic showed lowered serum cholesterol (p = 0.049), triglycerides (p = 0.001) and very low density lipoprotein (p = 0.032) when compared with the CON group. Regarding the polyunsaturated FA (PUFA) of breast muscles, synbiotic-supplemented birds had significantly lower n-6:n-3 ratio (p = 0.047), however, a greater hypocholesterolaemic to hypercholesterolaemic FA (H/H) ratio was reported when compared with the CON group (p = 0.002). Among the essential amino acids, the contents of leucine and methionine in the breast (p = 0.032 and 0.007 respectively) and thigh (p = 0.023 and 0.003 respectively) muscles were greater in the synbiotic-supplemented birds compared with the CON group. In conclusion, the synbiotic-supplemented diet improved the PUFA:SFA, n-6:n-3 and H/H ratios by altering the FA composition of broiler muscles, which are important with regards to human health.

Can we improve the nutritional quality of meat?

The nutritional value of meat is an increasingly important factor influencing consumer preferences for poultry, red meat and processed meat products. Intramuscular fat content and composition, in addition to high quality protein, trace minerals and vitamins are important determinants of nutritional value. Fat content of meat at retail has decreased substantially over the past 40 years through advances in animal genetics, nutrition and management and changes in processing techniques. Evidence of the association between diet and the incidence of human non-communicable diseases has driven an interest in developing production systems for lowering total SFA and trans fatty acid (TFA) content and enrichment of n-3 PUFA concentrations in meat and meat products. Typically, poultry and pork has a lower fat content, containing higher PUFA and lower TFA concentrations than lamb or beef. Animal genetics, nutrition and maturity, coupled with their rumen microbiome, are the main factors influencing tissue lipid content and relative proportions of SFA, MUFA and PUFA. Altering the fatty acid (FA) profile of lamb and beef is determined to a large extent by extensive plant and microbial lipolysis and subsequent microbial biohydrogenation of dietary lipid in the rumen, and one of the major reasons explaining the differences in lipid composition of meat from monogastrics and ruminants. Nutritional strategies can be used to align the fat content and FA composition of poultry, pork, lamb and beef with Public Health Guidelines for lowering the social and economic burden of chronic disease.

Significance of Increasing n-3 PUFA Content in Pork on Human Health

Evidence for the health-promoting effects of food rich in n-3 polyunsaturated fatty acids (n-3 PUFA) is reviewed. Pork is an important meat source for humans. According to a report by the US Department of Agriculture ( http://www.ers.usda.gov/topics ), the pork consumption worldwide in 2011 was about 79.3 million tons, much higher than that of beef (48.2 million tons). Pork also contains high levels of unsaturated fatty acids relative to ruminant meats (Enser, M., Hallett, K., Hewett, B., Fursey, G. A. J. and Wood, J. D. (1996) . Fatty acid content and composition of English beef, lamb, and pork at retail. Meat Sci. 44:443-458). The available literature indicates that the levels of eicosatetraenoic and docosahexaenoic in pork may be increased by fish-derived or linseed products, the extent of which being dependent on the nature of the supplementation. Transgenic pigs and plants show promise with high content of n-3 PUFA and low ratio of n-6/n-3 fatty acids in their tissues. The approaches mentioned for decreasing n-6/n-3 ratios have both advantages and disadvantages. Selected articles are critically reviewed and summarized.

M, Laudanović M, Teodorović V, Bošković M, Peurača M, Marković R. Effect of Sunflower, Linseed and Soybean Meal in Pig Diet on Chemical Composition, Fatty Acid Profile of Meat and Backfat, and Its Oxidative Stability

The aim of this study was to examine the effect of added sunflower, linseed or soybean meal to a standard pig fattening diet on the chemical composition, fatty acid profiles of meat and backfat, and on the oxidative stability of backfat from pigs. The content of saturated (SFA) and monounsaturated fatty acids (MUFA) was significantly lower (P<0.01), while content of polyunsaturated fatty acids (PUFA) was significantly higher (P<0.01) in the diet with added linseed. The feeding study was conducted on 30 pigs, with groups of 10 pigs fed one of the three different diets for 46 days before slaughter. There were no differences in the chemical composition (protein, water, fat, minerals) of meat from pigs fed the different diets. The content of SFA and MUFA was significantly higher, while the average PUFA content was significantly lower (P<0.01) in meat and backfat of pigs fed diet with added linseed. The content of n-6 fatty acids was significantly lower and n-3 fatty acids significantly higher, with more desirable n-6/n-3 ratio, in meat and backfat of pigs fed diet with added linseed. Malondialdehyde in the backfat of pigs fed diet with added linseed was significantly lower than that in the other two diet groups after the tissue was stored frozen at −20°C for 3, 6, 9 and 12 months.

Nutrigenomics and Beef Quality: A Review about Lipogenesis

The objective of the present review is to discuss the results of published studies that show how nutrition affects the expression of genes involved in lipid metabolism and how diet manipulation might change marbling and composition of fat in beef. Several key points in the synthesis of fat in cattle take place at the molecular level, and the association of nutritional factors with the modulation of this metabolism is one of the recent targets of nutrigenomic research. Within this context, special attention has been paid to the study of nuclear receptors associated with fatty acid metabolism. Among the transcription factors involved in lipid metabolism, the peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding proteins (SREBPs) stand out. The mRNA synthesis of these transcription factors is regulated by nutrients, and their metabolic action might be potentiated by diet components and change lipogenesis in muscle. Among the options for dietary manipulation with the objective to modulate lipogenesis, the use of different sources of polyunsaturated fatty acids, starch concentrations, forage ratios and vitamins stand out. Therefore, special care must be exercised in feedlot feed management, mainly when the goal is to produce high marbling beef.

Effects of the ratio of unsaturated fatty acid to saturated fatty acid on the growth performance, carcass and meat quality of finishing pigs

The effects on finishing pigs (80–100 kg BW) fed diets supplemented with oil sources containing different ratios of unsaturated to saturated fatty acids (UFA:SFA ratio) were evaluated in 15 barrows and 15 gilts (Duroc × Large White × Landrace). Three experimental diets were evaluated using a randomized complete block design, with broken rice, soybean meal and rice bran as the main feedstuffs in the control diet. Diets 2 and 3 consisted of the control diet supplemented with 3% oil, with UFA:SFA ratios of 2.5:1 and 5:1, respectively. Overall, there was no significant difference (P > 0.05) found in the average daily gain (ADG) of the pigs fed the treatment diets; however, the pigs fed the control diet and diet 3 had better (P < 0.05) feed conversion ratios (FCR) than the pigs fed diet 2. The pigs fed diets 2 and 3, which were supplemented with oil at UFA:SFA ratios of 2.5:1 and 5:1, had greater (P < 0.05) average daily feed intakes (ADFI) than the pigs in the control group. Additionally, it was found that the gender of the pigs had an effect (P < 0.05) on the FCR. Interaction effects between the experimental diets and the gender of the pigs (P < 0.05) were found in the ADFI and FCR. There were no significance differences (P > 0.05) among the treatment groups with regard to the carcass quality of the pigs; however, it was found that the gilts had greater (P < 0.01) loin eye areas than the barrows fed diets 2 and 3 and the loin eye area of pig fed diet 2 was the largest (P < 0.05). In the case of the meat quality parameters, it was clearly found that the pigs fed the control diet had a greater (P < 0.05) lightness (L^∗) in the meat colour, and the lowest cooking loss was found in the pigs fed the diet supplemented with fat containing the UFA:SFA ratio of 5:1. Overall, the dietary treatment did not significantly affect the drip loss, thawing loss and shear force of the pork. In conclusion, the supplementation of oil with UFA:SFA ratios of 2.5:1 and 5:1 has the potential to improve pork quality.

Lipid profile and cholesterol of pork with the use of glycerin in feeding

The aim of this work was to evaluate the effects of adding different levels of glycerin in the feeding on the lipid profile and cholesterol of the meat of finishing pigs. The experiment was arranged in a completely randomized design (CRD) with factorial 5x2, being five levels of glycerin in the diet and two genders. Sixty (60) swine of the Topigs genetics (30 barrows and 30 gilts) were used; they presented initial average weight of 79.3+4.0kg and were finished with the weight of 106.2+4.5kg. The levels of glycerin utilized were 0, 50, 100, 150 and 200g/kg in the natural matter. The analyses of lipid and cholesterol profile were conducted in the muscles longissimus dorsi(loin) andsemimembranosus (ham) on the left side of the carcasses. Interaction occurred between the levels of crude glycerin in the diet and the sexual category for the profile of fatty acids and cholesterol. On the loin the meat of the barrows presented higher means of C16:0, C16:1, C20:3ω3, C18:1ω9c, Total of saturated (SFA) and monounsaturated (MUFA) fatty acids. On the ham, increased means were found for the fatty acids C18:1ω9c, MUFA, activity of ∆9-desaturaseC18 and ElongaseC16-18in barrows. The sows' meat presented higher proportions of polyunsaturated fatty acids and of the series ω6 for both the cuts. The amount of cholesterol in the sows' meat presented increase according to the level of glycerin in the meat. The barrows' meat presented indices of atherogenicity greater than the gilts. The levels of glycerin altered the lipid profile and cholesterol content according to the sexual category, promoting a distinct effect on the loin and ham.

Effects of dietary n-6:n-3 PUFA ratio on fatty acid composition, free amino acid profile and gene expression of transporters in finishing pigs

Revealing the expression patterns of fatty acid and amino acid transporters as affected by dietary n-6:n-3 PUFA ratio would be useful for further clarifying the importance of the balance between n-6 and n-3 PUFA. A total of ninety-six finishing pigs were fed one of four diets with the ratio of 1:1, 2·5:1, 5:1 and 10:1. Pigs fed the dietary n-6:n-3 PUFA ratio of 5:1 had the highest (P< 0·05) daily weight gain, and those fed the dietary n-6:n-3 PUFA ratio of 1:1 had the largest loin muscle area (P< 0·01). The concentration of n-3 PUFA was raised as the ratio declined (P< 0·05) in the longissimus dorsi and subcutaneous adipose tissue. The contents of tryptophan, tasty amino acids and branched-chain amino acids in the longissimus dorsi were enhanced in pigs fed the dietary n-6:n-3 PUFA ratios of 1:1-5:1. The mRNA expression level of the fatty acid transporter fatty acid transport protein-1 (FATP-1) was declined (P< 0·05) in the longissimus dorsi of pigs fed the dietary n-6:n-3 PUFA ratios of 1:1-5:1, and increased (P< 0·05) in the subcutaneous adipose tissue of pigs fed the dietary n-6:n-3 PUFA ratios of 5:1 and 10:1. The expression profile of FATP-4 was similar to those of FATP-1 in the adipose tissue. The mRNA expression level of the amino acid transceptors LAT1 and SNAT2 was up-regulated (P< 0·05) in the longissimus dorsi of pigs fed the dietary n-6:n-3 PUFA ratios of 1:1 and 2·5:1. In conclusion, maintaining the dietary n-6:n-3 PUFA ratios of 1:1-5:1 would facilitate the absorption and utilisation of fatty acids and free amino acids, and result in improved muscle and adipose composition.

Volatiles in raw and cooked meat from lambs fed olive cake and linseed

This study was conducted to determine the effects of feeding olive cake and linseed to lambs on the volatile organic compounds (VOCs) in raw and cooked meat. Four groups of eight male Appenninica lambs each were fed: conventional cereal-based concentrates (diet C), concentrates containing 20% on a dry matter (DM) basis of rolled linseed (diet L), concentrates containing 35% DM of stoned olive cake (diet OC), or concentrates containing both rolled linseed (10% DM) and stoned olive cake (17% DM; diet OCL). The longissimus dorsi muscle of each lamb was sampled at slaughter and was subjected to VOC profiling through the use of SPME-GC-MS. In the raw meat, the concentration of 3-methylpentanoic acid was higher in treatment C as compared with treatments L, OC and OCL (P<0.01). Moreover the level of nonanoic acid was greater in treatments C and OC than in treatment L (P<0.05). With respect to alcohols, in raw meat the amount of 2-phenoxyethanol in treatment OCL was lower than in treatments C (P<0.01) and OC (P<0.05), while in cooked meat the amount of 1-pentanol was higher in treatment C than in treatment OC (P<0.05). Apart from these compounds, none of the lipid oxidation-derived volatiles was significantly affected by the dietary treatment. Therefore, the results suggest that the replacement of cereal concentrates with linseed and/or olive cake did not cause appreciable changes in the production of volatile organic compounds in lamb meat.