Breed effect on quality veal production in mountain areas: emphasis on meat fatty acid composition

This study was designed to compare the quality of veal produced from 'Tudanca×Charolais' cross (n=6) and Limousin (n=6) breeds when allowed to feed freely on mountain pastures and suckle naturally from birth to 7months of age. After 80days of age calves also had access to concentrate (maximum of 3kg/day), while mothers did not. At slaughter, Limousin calves were heavier (P<0.01) and provided better carcass yield (P<0.05) and conformation (P<0.001) than Tudanca calves. Tudanca beef provided higher fat content (P<0.05) was less tough (P<0.05), and was scored as more tender and juicy (P<0.1) with higher acceptability than Limousin beef (P<0.1). In general, Tudanca had a better fatty acid profile than Limousin beef, especially in terms of the content of polyunsaturated (P<0.05), long-chain polyunsaturated fatty acids (P<0.05) and their n-6/n-3 ratios (P<0.1), as well as vaccenic acid (P<0.1) and the overall trans-18:1 isomer profile.     

Effects of chestnut tannins on carcass characteristics,meat quality,lipid oxidation and fatty acid composition of rabbits

Seventy two male Bianca Italiana rabbits were used to study the effects of the inclusion (0%, 0.5%, and 1.0%) of a natural extract of chestnut wood (Silvafeed ENC) in the diet on productive traits, carcass characteristics, meat quality, lipid oxidation and fatty acid composition of rabbit meat. Results showed ENC had no significant effect on live weight, productive traits, hot carcass weight, dressing percentage, skin weight, pH, cooking losses, shear force and colour. The iron content was higher in Longissimus thoracis et lumborum (LTL) muscle of rabbit fed the ENC 1.0% diet than the control group. TBARS average values in the group ENC 0.5% were significantly lower (P < 0.05) than in the control and ENC 1.0% groups. Myristic acid (C14:0; P < 0.01), palmitoleic acid (C16:1 cis-9; P < 0.05) and pentadecanoic acid (C15:0; P < 0.01) contents were lower in LTL muscle of rabbits fed the ENC 1.0% diet, whereas the palmitic acid (C16:0) content was higher (P < 0.05) in the rabbits of this group. Moreover, the rabbits fed with the ENC 0.5% diet had lower (P < 0.01) levels of trans-vaccenic acid (C18:1 trans-11) compared to rabbits fed with the control diet. No significant differences were observed in saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) fatty acids, as well as in PUFA/SFA and n − 6/n − 3 ratios among the groups.     

Packaging-specific influence of chitosan on color stability and lipid oxidation in refrigerated ground beef

We examined the influence of chitosan on lipid oxidation and color stability of ground beef stored in different modified atmosphere packaging (MAP) systems. Ground beef patties with chitosan (1%) or without chitosan (control) were packaged either in high-oxygen MAP (HIOX; 80% O₂ + 20% CO₂), carbon monoxide MAP (CO; 0.4% CO + 19.6% CO₂ + 80% N₂), vacuum (VP), or aerobic packaging (PVC) and stored at 1 °C. Chitosan increased (P < 0.05) redness of patties stored in PVC and CO, whereas it had no effect (P > 0.05) in HIOX. Chitosan patties demonstrated lower (P < 0.05) lipid oxidation than controls in all packaging. Control patties in PVC and HIOX exhibited greater (P < 0.05) lipid oxidation than those in VP and CO, whereas chitosan patties in different packaging systems were not different (P > 0.05) from each other. Our findings suggested that antioxidant effects of chitosan on ground beef are packaging-specific.     

Effects of teeth maturity and fatness of Nellore (Bos indicus) steer carcasses on instrumental and sensory tenderness

This study sought to evaluate the effects of teeth maturity and carcass fatness on physical and sensory traits of the beef ribeye (M. longissimus thoracis). Carcass sides (n = 60) of Nellore steers were grouped into six categories, according to teeth maturity (2, 4 and 6 permanent incisors), and fatness (2 – slight and 3 – average). The boneless ribeye cuts (6th – 9th ribs) were vacuum packed and aged for 14 days. Steaks, 2.5 cm thick, were evaluated as to sarcomere length, shear force and sensory attributes. Sarcomere length was not affected (P > 0.05) by maturity or fatness. Teeth maturity did not influence (P > 0.05) tenderness measured by instrumental or sensory analysis, however rib steaks from fatter carcasses displayed better tenderness (P < 0.01) and lower cooking losses (P < 0.01). In the Nellore steer carcasses produced in Brazil, fatness may be more important than teeth maturity to improve meat tenderness.     

Effect of tomato by-products in the diet of Comisana sheep on composition and conjugated linoleic acid content of milk fat

To evaluate the effect of supplementing the diet of Comisana sheep with by-products from industrial tomato manufacture on the fat composition and conjugated linoleic acid (CLA) content of milk fat, two groups of 50 ewes each were fed either total mixed ration standard (TMRS) or total mixed ration with added tomato by-products (TMRA). Milk fat composition was determined by high-resolution gas chromatography (HRGC). The milk fat content for the animals fed the TMRA diet increased by 6.41% (P < 0.01) after six weeks, compared with the animals fed the TMRS diet. The CLA content in the milk fat for the group of animals fed the TMRA diet was 19.8% (P < 0.05) higher than for those fed the TMRS diet, and reached 1.33 g 100 g^?1 fat, while the polyunsaturated fatty acid (PUFA) content increased by a 6.43% (P < 0.05) and reached 7.12 g 100 g^?1 fat. The fatty acid composition showed an increase in the amount of polyunsaturated fatty acids. The n ? 3:n ? 6 ratio increased by 13% in the milk from sheep fed with the TMRA diet. These observations were confirmed by triglyceride analysis, which showed a decrease in the amount of short-chain (C₂₈–C₃₂) and medium-chain (C₃₄–C₄₂) triglycerides after six weeks, while the opposite was observed for the long-chain triglycerides (C₄₄–C₅₄).     

The effects of skeletal separation and moisture enhancement for improving the eating quality of cull cow beef

Sixty-two cull beef cows were slaughtered to investigate effects of skeletal separation and moisture enhancement on beef eating quality. Muscles from each carcass side were randomly assigned to 1) no postmortem processing (NPP), 2) prerigor skeletal separation (SS), 3) moisture enhancement (ME) using calcium ascorbate or 4) a combination of SS and ME (SS/ME). Postmortem processing treatment (PPT) by ageing (PM) interactions (P < 0.01) for shear force were present for longissimus. As PM ageing increased from 7 to 21 d, there was a greater decrease (P < 0.05) in shear force with NPP vs. all other PPT. Trained taste panellists found SS, ME and SS/ME improved (P < 0.05) palatability attributes vs. NPP. An additive effect of combining SS and ME improved palatability traits versus SS or ME alone. Panellists found no differences (P > 0.14) in softness and tenderness between SS/ME and Canadian AA or AAA beef. Postmortem processing of beef cows may produce beef as tender and juicy as beef from younger carcasses.     

Efficacy of spherical aberration correction based on contact lens power

PurposeTo investigate the efficacy of spherical aberration (SA) correction with aspheric contact lenses (aspheric lenses) based on lens power, and compare the results with those of spherical contact lenses (spherical lenses).MethodsOcular higher-order aberrations were measured with a wavefront sensor, in 11 myopic subjects wearing an aspheric lens (Medalist Fresh fit (PUREVISION 2 HD); Bausch + Lomb) or a spherical lens (ACUVUE Oasys; Johnson & Johnson). Six different lens powers (−7.00 diopters (D), −5.00 D, −3.00 D, −1.00 D, +1.00 D, +3.00 D) were used for all subjects. The amount of SA correction from the contact lens at each power was calculated as the difference between SA with the contact lens on-eye and SA of the eye alone.ResultsFor the spherical lenses, SA correction was close to 0.00 μm for the +1.00 D lens, became more positive as the labeled lens power increased and became more negative as the labeled lens power decreased. For the aspheric lenses, SA correction was consistent, from −0.15 to −0.05 μm, for all lens powers except for the −1.00 D lens. SA correction for the spherical and aspheric lenses was significantly different at −7.00 D (p = 0.040), −3.00 D (p = 0.015), −1.00 D (p < 0.001), +1.00 D (p = 0.006), and +3.00 D (p < 0.001) powers.ConclusionAn aspheric lens is capable of correcting SA at different lens powers, and has SA correction in the range of −0.15 to −0.05 μm over a 6 mm aperture.     

Comparison of the meat quality and fatty acid composition of traditional fat-tailed (Chall) and tailed (Zel) Iranian sheep breeds

The aim of this study was to compare the meat quality of a traditional fat-tailed breed, Chall, to a tailed Iranian sheep breed, Zel. Lambs were grazed on pasture until weaning, and then were finished until slaughter at 10–12 months. Meat quality traits were measured on the longissimus dorsi (LD) muscle. Zel lambs accumulated more intramuscular fat (IMF) (p < 0.01) and had lower shear force and drip loss than Chall lambs (p < 0.05). The meat color of Zel lambs was higher for both a* (p < 0.001) and b* (p < 0.01) compared to Chall lambs. Meat from Zel lambs was more tender (p < 0.01) and more juicy (p < 0.05) than Chall lambs. The PUFA:SFA fatty acid ratio (P:S) was higher (p < 0.05) and the n−6:n−3 PUFA ratio was lower in Chall compared to Zel lambs (p < 0.05). Overall, these results show that the eating quality of Zel lambs was better, but that this was at the cost of less favorable fatty acid profiles and poorer meat color.     

Effect of pre rigor stretching on beef tenderness development

The objective of this study was to determine effects of pre rigor stretching on beef tenderness development. Beef loins (M. longissimus dorsi; n = 24) were assigned to either stretching or non-stretching treatments and aged for 14 days at − 1.5 °C. Sarcomere length, shear force, water-holding capacity and proteolysis were determined for the loins at 1, 7 and 14 days of ageing. Stretching increased the length of the loins by 33% resulting in a trend of increasing sarcomere length (P = 0.19). However, no significant differences for shear force values, purge, drip and cooking losses between treatments were found. Shear force values decreased with ageing times (P < 0.05). Western blot assay found that stretching did not affect the extent of desmin degradation. The findings from the present study suggest that pre rigor stretching with the current increase in length will not contribute to tenderness improvement of the beef loins.     

Effects of reducing agents on premature browning in ground beef

This study was performed to investigate the effects of food-grade reducing agents on counteracting premature browning (PMB) and to determine the relative heat stability of different redox states of bovine myoglobin (Mb). Sodium erythorbate (SE), erythorbic acid (EA), sodium ascorbate (SA), ascorbic acid (AA) and ascorbyl palmitate (AP) were added to ground beef (15% fat) at a concentration of 2.3 mM; patties were prepared and stored at 4 °C and at −18 °C. Surface redness (a* values), lipid oxidation and total reducing activity (TRA) were measured on raw beef, and a* values recorded from cooked internal surfaces. Bovine Mb was purified from biceps femoris muscle and heat capacity was measured using differential scanning calorimetry. All reducing agents decreased lipid oxidation and increased TRA relative to controls (p < 0.05). In general, SE and SA were more effective at maintaining red color in cooked ground beef patties than other reducing agents (p < 0.05). The temperature at peak heat capacity, T_m, of metmyoglobin appeared lower than that of oxymyoglobin and deoxymyoglobin. Reducing agents can maintain Mb in the reduced state, and their addition to ground beef may be one method of preventing PMB.     

Effect of low and high pulsed electric field on the quality and nutritional minerals in cold boned beef M. longissimus et lumborum

The present research investigated the effects of low PEF (LPEF, 2.5 kV, 200 Hz and 20 μs) and high PEF (HPEF, 10 kV, 200 Hz and 20 μs) on the quality of cold-boned beef loins at 1 and 14 days of post-treatment. HPEF increased (P < 0.001) the temperature of the beef M. longissimus et lumborum (LL) samples. HPEF samples had higher (P = 0.007) shear force than LPEF samples and control samples were not different from either. HPEF beef LL samples had higher L* values and lower a* values (P < 0.001) compared to LPEF and control samples. Higher lipid oxidation (P = 0.013) was found in HPEF samples compared to LPEF samples. Lower (P < 0.01) P, K and Fe concentrations were found in HPEF samples compared to LPEF samples. The results suggest that high intensity PEF treatment can negatively affect the quality of beef.     

Effect of the addition of fatty acids on rice starch properties

The effect of the addition of the two fatty acids (stearic and linoleic acid) on starch pasting, thermal properties and the leaching of amylose during the gelatinization process are presented. The addition of stearic acid (C18:0) at 1.0% level (w/w, on the basis of starch) significantly changed starch pasting characteristics in peak viscosity (P < 0.05), breakdown (P < 0.001) and time to peak viscosity (P < 0.001) as measured by RVA. In contrast, the addition of linoleic acid (C18:2) showed less impact on the three RVA parameters. Thermal studies with DSC suggested that the addition of both fatty acids did not significantly influence the starch gelatinization behaviour as reflected in peak width and enthalpy but there was a decrease in peak temperature. However, the addition of the saturated fatty acid produced a significant decrease in the retrogradation endotherm (P < 0.01) compared to that of native starch. It is suggested that the saturated fatty acid complexes with amylose and is preferentially introduced into the starch granule. The double bond in the linoleic acid apparently hinders complexation. After complexation, hydrophobicity was further enhanced with the content of amylose in the hot-water soluble fraction being significantly reduced (P < 0.01) as determined by HPLC.     

Bioactivity of ellagic acid-, lutein- or sesamol-enriched meat patties assessed using an in vitro digestion and Caco-2 cell model system

Interest exists in the manufacture of functional meat products whereby synthetic antioxidants are replaced with naturally-sourced compounds. Therefore the aim of this study was to determine the bioactivity of pork and beef patties containing ellagic acid (600 μg/g), lutein (200 μg/g) or sesamol (500 μg/g). Cooked pork and beef patties were subjected to an in vitro digestion procedure and the resultant micelles were added to human intestinal Caco-2 cells. Supplementation with micelles from lutein-enriched pork patties protected (P < 0.05) against H₂O₂-induced cell injury whereas the presence of control beef, lutein-enriched beef or ellagic acid-enriched beef, at levels ?20% (v/v), enhanced (P < 0.05) oxidant-induced cytotoxicity. None of the pork patties significantly modulated cellular glutathione content. Micelles from all the enriched pork patties significantly protected against H₂O₂-induced DNA damage. In conclusion, the cytoprotective and genoprotective effects of ellagic acid, lutein, and sesamol, when incorporated into meat systems, depend greatly on the food matrix.     

Frozen storage characteristics of low-salt and low-fat beef patties as affected by Wakame addition and replacing pork backfat with olive oil-in-water emulsion

Characteristics of beef patties with low-salt (0.5%) and low-fat (<10%) contents were studied during frozen storage as affected by addition of Wakame seaweed (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. Patties with Wakame presented less (P < 0.05) thawing and cooking losses and were softer (P < 0.05) than patties without seaweed. A softening effect (P < 0.05) induced by olive oil emulsion was observed only in seaweed-free patties. Lipid oxidation and microbiological counts in reformulated products were not a limiting factor for frozen stability. Wakame incorporation increased (P < 0.05) mineral contents, but all products presented the same Na/K ratio. Observed changes in microstructure were associated with seaweed addition (formation of alginate chains). All products were judged acceptable by the sensory panel. In the course of frozen storage no important changes were found in the target properties due to the different treatments.     

Preventive effects of caffeic acid on lipids,lipoproteins and glycoproteins in isoproterenol induced myocardial infarcted rats

Dietary phenolic compound intake has been reported inversely related to the incidence of cardiovascular diseases. The aim of this research was to understand the preventive effects of caffeic acid, a phenolic acid on lipids, lipoproteins and glycoprotein components in isoproterenol induced myocardial infarcted rats. Rats were pretreated with caffeic acid (15 mg/kg body weight) daily for a period of 10 days. After pretreatment, rats were induced myocardial infarction by subcutaneous injection of isoproterenol (100 mg/kg body weight). Isoproterenol induced myocardial infarcted rats showed significant (P < 0.05) decreased levels of heart phospholipids and significant (P < 0.05) increased levels of serum and heart cholesterol, triglycerides, free fatty acids and serum phospholipids. Isoproterenol also significantly (P < 0.05) increased low density and very low density lipoprotein cholesterol and significantly (P < 0.05) decreased high density lipoprotein cholesterol levels. The activity of liver 3-hydroxy-3methyl glutaryl-coenzyme-A-reductase was significantly (P < 0.05) increased and lecithin cholesterol acyl transferase activity was significantly (P < 0.05) decreased in isoproterenol induced myocardial infarcted rats. In addition, the levels of glycoprotein components in the serum and heart were significantly (P < 0.05) increased in myocardial infarcted rats. Pretreatment with caffeic acid positively altered all the above mentioned biochemical parameters studied in isoproterenol induced myocardial infarcted rats.In conclusion, caffeic acid protected the rat's heart from the deleterious effects of lipids, lipoproteins and glycoproteins by its antilipidemic and antiglycative effects in isoproterenol induced myocardial infarcted rats. A diet containing caffeic acid may be beneficial to myocardial infarction.     

Effects of dry aging of bone-in and boneless strip loins using two aging processes for two aging times

This experiment investigated the combined effects of two dry-aging methods (unpackaged and in a bag), two loin-cut styles (bone-in shell loins and boneless strip loins), and two aging times (21 and 28 days) on the physical, chemical, sensory, and microbial properties of dry-aged beef. Sections from shell and strip loin were assigned randomly to be aged unpackaged or aged packaged in a bag with high moisture permeability. Weight losses increased with aging time. Shell loins lost more (P < 0.05) weight during aging compared with strip loins; dry aging in a bag had less (P < 0.05) weight loss than unpackaged aging. There were no differences (P > 0.05) in any of the sensory traits between shell and strip loins or dry aging using a traditional method or in a bag. Dry aging in a bag creates positive effects on yields, no negative effects on product quality, and adds flexibility and control of the aging environment.     

Changes in meat quality of ovine longissimus dorsi muscle in response to repeated freeze and thaw

Changes in eating and technological quality attributes of ovine longissimus dorsi muscle during repeated freeze and thaw were investigated. Shear force value, L* value, a* value and fiber diameter decreased (P < 0.05) but lipid oxidation increased (P < 0.05) with repeated freeze–thaw cycles. Sarcomere length and pH decreased (P < 0.05) within the first 10 freeze–thaw cycles but increased (P < 0.05) after 5 further cycles. Total and myofibrillar protein solubility, and intramuscular free fatty acids concentration decreased (P < 0.05) after 1 cycle of freeze and thaw but then increased (P < 0.05) gradually with further cycles. Hardness, chewiness, cohesiveness and resilience of comminuted lamb products decreased (P < 0.05) with increased freeze–thaw cycles. And therefore, repeated freeze and thaw should be minimized in terms of meat color for commercial value and water holding capacity for further processing.     

The assessment of carcass composition of Awassi male lambs by real-time ultrasound at two different live weights

The accuracy of ultrasonography to measure fat thickness (FT) and longissimus dorsi muscle (LM) traits (area, depth and width) in live Awassi male lambs and predict carcass FT and LM traits was studied.Twenty six Awassi male lambs were randomly divided into light (L) (n = 13) and heavy (H) (n = 13) finishing lambs. Slaughter weight of lambs in L and H groups were 40 and 45 kg, respectively. FT and LM traits, cross-sectional area between the 12th and 13th rib were measured using real-time ultrasound in vivo and on the carcass after slaughter. All ultrasound and carcass measurements were the same except live weight (LW) (P < 0.001), cold carcass weight (CCW) (P < 0.001) and carcass LM width (P < 0.05). Overall, correlation coefficients between ultrasound and carcass FT, LM depth, width and area were 0.79, 0.82 (P < 0.001); 0.60, 0.58 (P < 0.05); 0.48, −0.17 (P > 0.05) and 0.89, 0.87 (P < 0.001), respectively, for lambs in L and H groups. The introduction of ultrasound FT and ultrasound LM area as independent variables in addition to LW in the multiple regression equations further improved the variations for carcass FT (84%, 71%), carcass LM area (79%, 79%), CCW (72%, 65%) for lambs in light and heavy groups whereas no improvement was observed for carcass yield.These results indicate that in vivo ultrasound FT and measurement of the LM area in association with LW could be used to estimate carcass FT, carcass LM area and CCW in different LW Awassi lambs.     

Influence of inclusion of chestnut in the finishing diet on fatty acid profile of dry-cured ham from Celta pig breed

The effect of the inclusion of chestnut in the finishing diet on fatty acid profile of dry-cured Celta ham was studied. Twelve hams of each type (from three different diets: concentrate, mixed and chestnut) were used. Significant differences between treatments (P < 0.001) were found regarding total saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). Ham samples from the mixed and chestnut groups had less SFA (35.57% and 35.63%, respectively) with respect to ham samples from the concentrate group (40.33%), while hams from the mixed and chestnut batches showed higher values of MUFA than hams from the concentrate group (50.70 vs. 49.79 vs. 43.85, P < 0.001, respectively). From a nutritional point of view, Celta hams from chestnut diets could be considered as healthier regarding their fatty acid profiles (low n−6/n−3 ratio and high hypocholesterolemic/Hypercholesterolemic ratio). Discriminant analysis selected five variables (C_16:0, C_16:1cis-9, C_20:2, C_20:3n−6 and C_20:4n−6) and calculated two discriminating functions which verifies the presence of chestnut in the finishing diet.     

Feeding strategy for improving tenderness has opposite effects in two different muscles

Compensatory growth has been shown to affect rate of muscle protein turnover and may potentially improve tenderness of beef. Thus, a study of tenderness in relation to feeding regime and slaughtering at a time with maximal muscle protein degradation was performed. Friesian bull calves (5-month-old) were fed either ad libitum (n = 6) (AA) or restrictively for 3 months followed by re-alimentation for 6 weeks (n = 6) (RA) before slaughter at 10 months. At slaughter the fractional breakdown rate of muscle protein was 2.4% in RA compared with 1.6% in AA (P < 0.06). Sensory profiling revealed superior texture of M. semimembranosus from RA compared with AA, whereas M. longissimus was superior in texture from AA compared with RA, with no difference in proteolysis and shear force. In conclusion it was clear that different muscles in terms of tenderness responded very differently to the nutritional manipulation.