Effects of dietary vitamin A restriction during finishing on color display life, lipid oxidation, and sensory traits of longissimus and triceps brachii steaks from early and traditionally weaned steers

Our objective was to determine the effects of vitamin A restriction during finishing on color display life, lipid oxidation, and sensory traits of longissimus lumborum (LL) and triceps brachii (TB) steaks from early and traditionally weaned steers. Forty-eight steers weaned at either 137 ± 26 days (EW) or 199 ± 26 days (TW) were supplemented with either 15,400 IU/kg dry matter of vitamin A (HA) or restricted to no supplemental vitamin A (LA) during finishing for 210 and 150 days, respectively. Both LL and TB steaks from the HA steers had the darkest (P < 0.05) color scores after 3 days of retail display in PVC packaging at 2 °C, and the highest (P < 0.05) thiobarbaturic acid reactive substances (TBARS) values. Instrumental a∗, b∗, and saturation index values were lowest (P < 0.05) in LL steaks from the HA steers. Instrumental L∗ values were lower (P < 0.05) on days 4–6 in TB steaks from TW steers fed LA than those from EW steers fed HA. No differences were found in Warner–Bratzler shear force values or sensory traits in either muscle. No supplemental vitamin A versus high levels of vitamin A inclusion in finishing diets has potential to increase color display life and reduce lipid oxidation, with no effects on meat palatability.     

Comparison of ascorbic acid and sodium erythorbate: Effects on the 24h display colour of beef lumbar vertebrae and longissimus lumborum packaged in high-oxygen modified atmospheres

Sodium erythorbate and ascorbic acid were compared as a means to stabilize surface colour of bone-in beef steaks in high-oxygen modified atmosphere (80% oxygen and 20% carbon dioxide). Bone-in strip loins (n = 8) were fabricated into 1.9 -cm thick steaks, of which both the lumbar vertebrae and longissimus lumborum were topically treated with either ascorbic acid or sodium erythorbate (0, 0.05, 0.1, 0.5, 1.0, or 1.5%, wt/wt basis). Colour (L^∗a^∗b^∗) was evaluated before treatment and 24 h after packaging (display at 1 °C). Sodium erythorbate was as effective as ascorbic acid for inhibiting vertebrae discolouration (P > 0.05). Either reducing agent at 0.5, 1.0, or 1.5% improved (P < 0.05) vertebrae redness (compared with 0%, 0.05% and 0.1%). No detrimental effects on muscle colour were observed. When selecting antioxidants intended for bone-in beef steaks displayed in high-oxygen packaging, sodium erythorbate may be a cost effective substitute for ascorbic acid.     

Influence of vacuum-aging period on bloom development of the beef gluteus medius from top sirloin butts

The gluteus medius (GM) from USDA Select beef carcasses was used to test the effect of aging period on bloom development. Top sirloin butts (IMPS #184) were randomly allocated to 0, 7, 14, 21, 28, and 35 d vacuum-aging at 2 °C (n = 10/aging period). Each week, aged top sirloin butts were faced before two 2.5-cm-thick, non-adjacent steaks were cut and instrumental color (L^∗, a^∗, and b^∗) of the GM was measured at 10-min intervals for 2 h after cutting. Steaks aged for 7 and 14 d were a more vivid (greater chroma values; P < 0.05), redder (greater a^∗ values; P < 0.05), and more yellow (greater b^∗ values; P < 0.05) color than steaks from the other aging periods. Change in total color (ΔE) was greater (P < 0.05) for steaks from top sirloin butts aged 7, 14, and 21 d than steaks from top butts aged 28 and 35 d, whereas oxymyoglobin percentages for steaks from top butts aged 7 and 14 days were greater (P < 0.05) than those from top sirloin butts aged 28 and 35 d. As much as 90% of the total increase (P < 0.05) in a^∗, b^∗, and chroma values, as well as hue angles and oxymyoglobin percentages, was achieved during the first 60 min after cutting.     

Effect of illumination on the display life of fresh pork sausages packaged in modified atmosphere. Influence of the addition of rosemary, ascorbic acid and black pepper

Pork forelegs were used for manufacturing fresh sausages, treated with different natural antioxidants (rosemary, ascorbic acid and black pepper), packaged in 80% O₂ + 20% CO₂ atmosphere and displayed at 2 ± 1 °C under different lightings (darkness, standard fluorescent, low-UV colour-balanced lamp and standard fluorescent plus a UV-filter). Two packs for each treatment were opened every 4 days for subsequent analysis of colour CIE L^∗, a^∗, b^∗, TBARS, microbial psychrotrophic aerobes and sensory discolouration and off-odour. Lighting with standard fluorescent was highly deleterious for sausage display life, which fell from 12 to 8 days due mainly to early discolouration. Inserting a UV-filter extended display life to 12 days, while the use of a low-UV lamp was not effective in protecting from discolouration. Addition of rosemary plus ascorbic acid, in the absence of black pepper, retarded discolouration only in sausages illuminated with the UV-filter, reaching a display life of 16 days, equal to that of sausages maintained in the dark.     

Effect of stunning systems on meat quality of Manchego suckling lamb packed under modified atmospheres

The effects of the type of stunning (TS) [electrically vs. gas] and packing in modified atmospheres (MA) [MA-A: 30% CO₂/70% O₂; MA-B: 30% CO₂/69.3% N₂/0.7% CO; MA-C: 40% CO₂/60% N₂] on meat quality (pH), drip losses (DL), water holding capacity (WHC), shear force (SF) and instrumental colour (L^∗, and C^∗chroma) of suckling lamb of the Spanish Manchego breed at 7, 14 and 21 d post-packing was studied. Acceptance of meat samples (on the basis of colour and odour) was determined. In general neither the TS nor the MA affected the pH values. Meat from the gas stunned lambs had the lowest DL (P < 0.001 at 14 d post-packing), but lower WHC (more water expelled; P < 0.01 at 14 and 21 d post-packing), was more tender (P < 0.01) and had higher L^∗ (P < 0.001 at 14 d post-packing) and C^∗ values (P < 0.001) than the electrically stunned group. Similar values of WHC and SF were observed for all MA types but the use of CO in the packs (MA-B) caused less DL, gave the highest C^∗ values, acceptability and colour stability with time of storage.     

Effects of packaging atmospheres on shelf-life quality of ground ostrich meat

Fresh ground ostrich meat was packaged under high oxygen (O2), high nitrogen (N2), vacuum (VAC) and ambient air (AIR) atmospheres, stored at 4 ± 1 °C and displayed under 1700 ± 100 lux of fluorescent lighting for 9 days. The meat was evaluated for changes in typical shelf-life characteristics consisting of pH, color properties (CIE L^∗, a^∗, b^∗, and total color difference, ΔE), oxidative changes (thiobarbituric acid value and hexanal content) and bacterial counts (total viable cell, coliform, lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp.) Initial meat pH was 6.16 and declined slightly during storage. TBA values and hexanal content were highest in O2 and lowest (P ? 0.05) in VAC and N2 atmospheres. Surface lightness (L^∗) and redness (a^∗) were highest in O2 packaging initially, decreasing (P ? 0.05) by day 9. ΔE of the ground ostrich increased during storage in only O₂ and AIR packaging. All packaging methods had generally similar effects on microbial outgrowth. Total aerobic bacteria attained >10⁶ CFU/g meat between day 3 and day 6. Ground ostrich meat was below saleable quality in less than 6 days based on all of the meat attributes. For O2 packaging however, quality based on lipid oxidation and color properties indicated a shelf-life of less than 3 days. Oxidation is likely the limiting factor for shelf-life of ground ostrich meat.     

Dietary tannins improve lamb meat colour stability

Fourteen male Comisana lambs were divided into two groups at 45 days of age: lambs fed a concentrate diet (C), or lambs fed the same concentrate with the addition of quebracho (Schinopsis lorentzii) tannins (T). Sheep were slaughtered at 105 days of age. Lipid oxidation, colour coordinates, haem pigment concentration, and metmyoglobin percentages were measured on minced semimembranosus muscle (SM) over 14 days of refrigerated storage in a high oxygen modified atmosphere. Tannin supplementation increased (P < 0.01) a^∗ values and reduced (P < 0.01) b^∗ values of the SM when compared to C. Lower hue angles (P < 0.001) and metmyoglobin formation (P = 0.07) were observed in lamb from T-fed compared to C-fed sheep during the 14-days storage period. Furthermore, feeding T resulted in greater (P < 0.001) haem pigment concentrations in the SM during refrigerated storage; however, diet had no (P = 0.28) effect on lipid oxidation. Therefore, including quebracho tannins in sheep diets can improve meat colour stability of fresh lamb during extended refrigerated storage.     

Ability of near infrared reflectance spectroscopy (NIRS) to estimate physical parameters of adult steers (oxen) and young cattle meat samples

The potential of NIRS-based models to predict several physical parameters of oxen and young cattle beef protected by a quality mark was evaluated. Fifty-three and 67 samples of Longissimus thoracis muscle corresponding to oxen and young cattle reared in extensive conditions were analyzed for pH, colour (L^∗, a^∗, b^∗), water holding capacity (WHC) and Warner–Braztler shear force (WBSF), according to the conventional methods. Several factors which might have jeopardized the prediction of pH, a^∗, WHC and WBSF by NIRS are considered in the discussion section. However, the best NIR calibrations, tested by full cross-validation, were for L^∗ (R² = 0.869; SE_CV = 1.56) and b^∗ (R² = 0.901; SE_CV = 1.08) colour parameters in meat samples from young cattle. It can be concluded that NIRS could be a useful tool for estimating the colour of young cattle meat samples, primary consideration for consumers when making purchasing decisions.     

Influence of carbon monoxide in package atmospheres containing oxygen on colour, reducing activity, and oxygen consumption of five bovine muscles

Steaks from five bovine muscles [psoas major (PM), longissimus lumborum (LL), deep semimembranosus (DSM), superficial semimembranosus (SSM), and semitendinosus (ST)] were packaged in atmospheres containing 20% or 80% oxygen, with and without 0.4% carbon monoxide. Steaks were evaluated on d 0, 4, and 7 of retail display for instrumental (CIE L^∗, a^∗, and b^∗) and visual colour, total- and metmyoglobin-reducing activity, and oxygen consumption rate. Combining carbon monoxide with either oxygen level had no effect (P > 0.05) on any measured attribute. Using higher oxygen levels increased colour stability and reduced variability (P < 0.05) among muscles for all measured attributes. In general, colour stability and reducing activity for the muscles were LL > ST > SSM > PM > DSM. Including 0.4% carbon monoxide with 20% or 80% oxygen may not have impacted colour, due to preferential formation of oxymyoglobin, rather than carboxymyoglobin, at these oxygen levels.     

Effect of carbon monoxide packaging and lactate enhancement on the color stability of beef steaks stored at 1°C for 9 days

Our objective was to assess the effects of lactate enhancement in combination with different packaging systems on beef longissimus lumborum and psoas major steak color. Strip loins and tenderloins (n = 16) were assigned to one of four injection treatments (non-injected control, water-injected control, 1.25%, and 2.5% lactate in the finished product). Steaks were individually packaged in either vacuum, high-oxygen (80% O₂/20% CO₂), or 0.4% CO (30% CO₂/69.6% N₂) and stored for either 0, 5, or 9 days at 1 °C. The L^∗ and a^∗ values of both the longissimus and psoas responded similarly to lactate, which at 2.5% darkened steaks (P < 0.05) packaged in all atmospheres and improved (P < 0.05) the redness of steaks packaged in high-oxygen. Packaging steaks in CO did not counteract the darkening effects of lactate. Nevertheless, CO improved (P < 0.05) color stability compared with high-oxygen packaging.     

Suitability of Norwegian short-tail lambs, Norwegian dairy goats and Cashmere goats for meat production - Carcass, meat, chemical and sensory characteristics

Six female Norwegian lambs (29 kg body weight, 8 months old), six castrated Norwegian goats (27 kg body weight, 10 months old) and six castrated Cashmere goats (20 kg body weight, 8 months old) were used to study the relative potential of Norwegian lambs, Norwegian goats and Cashmere goats for meat production. Animals were fattened on silage and commercial concentrate before slaughter. Lamb meat had 4 % lower (P < 0.05) proteins and 13% higher (P < 0.05) fat content than goat meats. Moreover, m. longissimus dorsi samples from lambs were less red (a^∗) (P < 0.05) and had lower colour intensity (C) and wider hue angle (H) than that from goats. Meat from lambs and Cashmere goats had higher proportions of saturated fatty acids (SFA) (P < 0.001), especially stearic acid and lower ones for total unsaturated fatty acids (TUFA) and monounsaturated fatty acids (MUFA) than the meat from Norwegian goats. Sensory panellists scored lamb meat fattier, juicier and more tender than goat meats. Meat from Cashmere goats scored highest (P < 0.05) in whiteness, and lowest (P < 0.05) in both colour tone and colour intensity. It is concluded that, since C18:0 was the main contributor of SFA in meat from Norwegian lamb and Cashmere goats, meats from them are nutritionally comparable to that from Norwegian goats. However, the higher proportion of SFA in Norwegian lambs and Cashmere goats may increase hardness of fat and being easily solidified upon cooling, may influence meat palatability.     

Meat quality of Nguni, Bonsmara and Aberdeen Angus steers raised on natural pasture in the Eastern Cape, South Africa

The current study compared meat quality of Nguni, Bonsmara and Angus steers raised on natural pasture. Fifteen seven-month-old weaners of each breed were kept at the University of Fort Hare Farm for 12 months till slaughter. Monthly weights of the steers were recorded. Carcasses were electrically stimulated. The m. longissimus thoracis et lumborum was sampled for the measurement of meat colour, pH, drip loss, sarcomere length, myofibrillar fragmentation length and Warner Bratzler (WB) shear force. The Nguni had the highest (P < 0.05) average daily gain. Bonsmara and Angus steers had higher (P < 0.05) carcass weight and dressing percentage than the Nguni steers. Meat quality characteristics were similar among all the breeds except that Nguni meat was darker (L^∗) (P < 0.05) than meat from the other two breeds. The respective L^∗ values for Nguni, Bonsmara and Angus steers were 36.5, 38.6 and 39.9. There were significant (P < 0.05) correlations among some meat quality traits. There were significant (P < 0.05) correlations between WB values of meat aged for 2 and 21 days in Nguni and Bonsmara, but not in Angus. Meat quality from Nguni compares favourably with that from established breeds, when raised on natural pasture.     

Tensile properties of cooked meat sausages and their correlation with texture profile analysis (TPA) parameters and physico-chemical characteristics

The possibilities of using breaking strength (BS) and energy to fracture (EF) for monitoring textural properties of some cooked meat sausages (chopped, mortadella and galantines) were studied. Texture profile analysis (TPA), folding test and physico-chemical measurements were also performed. Principal component analysis enabled these meat products to be grouped into three textural profiles which showed significant (p < 0.05) differences mainly for BS, hardness, adhesiveness and cohesiveness. Multivariate analysis indicated that BS, EF and TPA parameters were correlated (p < 0.05) for every individual meat product (chopped, mortadella and galantines) and all products together. On the basis of these results, TPA parameters could be used for constructing regression models to predict BS. The resulting regression model for all cooked meat products was BS = −0.160 + 6.600 ∗ cohesiveness − 1.255 ∗ adhesiveness + 0.048 ∗ hardness − 506.31 ∗ springiness (R² = 0.745, p < 0.00005). Simple linear regression analysis showed significant coefficients of determination between BS (R² = 0.586, p < 0.0001) versus folding test grade (FG) and EF versus FG (R² = 0.564, p < 0.0001).     

Effects of peanut skin extract on quality and storage stability of beef products

Peanut skins are a low-value byproduct of peanut processing operations. They have been found to contain significant levels of natural antioxidants, but their antioxidant activity in muscle foods is unknown. The effects of peanut skin extracts on oxidation (TBARS) and color (CIE L^∗a^∗b^∗) was studied in ground beef and ground beef with added salt, phosphate (STP) and nitrite/erythorbate. Cooking loss, microbial growth, aroma acceptability and texture were also examined. The most significant reduction in oxidation was in ground beef or samples with salt, followed by phosphate (STP) or nitrite/erythorbate. Because of their low effective concentrations (200 ppm), the extracts did not cause color change (P > 0.05) of the products indicated by CIE L^∗a^∗b^∗ value. The extracts had no effect (P > 0.05) on sensory aroma. The phenolic extract from peanut skin had no effect (P > 0.05) on the cooking loss of the ground beef as well as the cured and uncured formulated products. The microbial growth in fresh ground beef was not affected (P < 0.05) by the phenolic extract.     

Meat quality traits of commercial hybrid pigs in Argentina

This report describes the meat quality of two INTA hybrids (hybrid females) sired by Duroc (D) or Yorkshire (Y) boars and a third one from PIC (S), a cross of females C22 to 412 boars. Starting at 30 kg live weight, 18 barrows and 18 gilts of each genotype were kept in identical conditions until slaughtered at 110 kg. Longissimus dorsi muscles were analyzed. Means differed significantly (P < 0.05) for drip loss (higher in S); tenderness (more tender in D), water holding capacity (higher in Y); cooking loss (higher in Y); colour parameter L^∗ (lower in D) and b^∗ (higher in S) and intramuscular fat content (higher in D). As a result of sensory analysis, it was found that D was the most tender and juicy. There were few sex effects and no genotype–sex interactions. Distinct differences in meat quality between hybrids do exist, with D superior, S the worst, and Y intermediate.     

Ability of α-tocopherol,taurine and rosemary,in combination with vitamin C,to increase the oxidative stability of beef steaks packaged in modified atmosphere

Fresh beef steaks were sprayed on the surface with vitamin C (500 ppm), taurine (50 mM), rosemary (1000 ppm) and vitamin E (100 ppm), the three latter in combination with 500 ppm of Vitamin C, packaged in modified atmosphere (70% O₂+20% CO₂+10% N₂) and stored at 1±1 °C for 29 days. Metmyoglobin formation, lipid oxidation (TBARS), instrumental colour (CIE a¹), psychrotrophic bacterial counts (PCA) and sensory discolouration and odour were determined. Results demonstrated that surface application of antioxidant combinations resulted in an effective delay of oxidative deterioration of fresh beef steaks. Shelf life was extended beyond that of control, according to evaluation of sensory attributes. Both combinations of vitamin C with either rosemary or taurine significantly (P<0.01) extended the shelf life of fresh beef steaks by about 10 days. Rosemary was the most effective in delaying oxidation processes. The combination of vitamins E and C was significantly (P<0.01) less effective than those combinations in delaying meat oxidation.     

CT scanning carcases has no detrimental effect on the colour stability of M. longissimus dorsi from beef and sheep

This study investigated the effect of computerised tomography imaging (CT scan), for carcase composition determination, on the oxy/metmyoglobin ratio, hue and L^∗, a^∗ and b^∗ scores of M. longissimus dorsi from both beef and lamb. Beef and lamb M. longissimus dorsi were divided into four proportions and randomly allocated to one of the following treatments; CT 30 day aged; CT fresh; control 30 day aged; control fresh. Colour measurements were made over a 96 h retail display period. CT scan had little effect on the colour of both lamb and beef across all colour parameters. There was a small negative affect observed in CT aged samples (P < 0.05) for ratio, hue, a^∗ and b^∗ values, however these differences were so small that they are unlikely to impact upon the commercial shelf-life of the product. Other factors such as aging, species and vitamin E concentration play a much greater role in colour stability than CT. Aged M. longissimus dorsi clearly had a worse colour stability than the fresh packaged samples, while beef was a lot more colour stable than lamb. It appears that CT scan for the purpose of body composition determination will not have any commercially relevant impact on colour stability of both beef and lamb.     

Combination effects of ultra-high pressure and temperature on the physical and thermal properties of ostrich meat sausage (yor)

Ostrich meat sausages (yor) were subjected to ultra-high pressures of 300, 500 and 700 MPa for 40 and 60 min at 40 and 60 °C. Subsequently the physical properties of the products, colour, released and expressible water, gel strength and stress relaxation as well as their thermal characteristics (by differential scanning calorimeter, DSC) were determined. The effects of pressure, temperature and holding time significantly influenced the L^∗, a^∗ and b^∗ values. The amount of released plus expressible water significantly decreased with increasing pressure, temperature and holding time. The gel strength and equilibrium stress increased with increasing severity of treatment. DSC thermograms indicated that pressures of 700 MPa yielded gel networks involving completely denatured protein with the ability to retain water.     

Burdizzo pre-pubertal castration effects on performance, behaviour, carcass characteristics, and meat quality of Holstein bulls fed high-concentrate diets

The effects of Burdizzo pre-pubertal castration on performance, behaviour, carcass, and meat quality of Holstein bulls fed high-concentrate diets were evaluated. Two hundred bulls (8.0 ± 0.42 months old) were randomly assigned to control (CTR) or Burdizzo castration (BURD). After 121 d, ADG, BW, and HCW were greater in CTR animals than in BURD animals, as well as, the agonistic and sexual behaviour. However, carcass fatness and intramuscular LT (longissimus thoracis) fat percentage were greater in BURD animals than in CTR animals. Additionally, CTR animals showed lower L^∗, a^∗, and b^∗ than BURD. The WBSF was smaller (P < 0.01) in BURD than in CTR bulls at all ageing days, and in both treatments decreased (P < 0.01) from 0 to 7 d of ageing. Additionally, at day 0 of ageing, meat from BURD animals showed similar WBSF to meat from CTR bulls after 7 d of ageing. However, 23% of BURD animals did not have a complete testicular atrophy, suggesting that the method of castration was not completely effective.     

Carcass, sensory, fat color, and consumer acceptance characteristics of Angus-cross steers finished on ryegrass (Lolium multiflorum) forage or on a high-concentrate diet

Fall-born Angus-cross steers (n = 30) from 1 of 2 sires, were randomly assigned to either an 85% corn, 7.5% cotton-seed hulls, and 7.5% vitamin/mineral/urea supplement diet (GRAIN), 100% ryegrass grazing (RG), or ryegrass grazing then the GRAIN diet for 94 d (RG/GRAIN). USDA Yield Grade of steers finished on either the GRAIN or RG/GRAIN regimens were higher (P < 0.02) compared to those finished on RG. Marbling score and USDA Quality Grade did not differ (P = 0.21 and 0.12, respectively) among the three finishing regimens. Yellowness (b^∗) values of the subcutaneous fat from both strip loins (SL) and ribeye (RE) rolls was lowest (P < 0.05) in cuts taken from steers finished on GRAIN. Subcutaneous fat of both SL and RE had lower L^∗ and hue angle values, and higher a^∗ and b^∗ values before trimming than after the fat was trimmed to 0.3 cm. Initial and sustained tenderness scores of SL from steers finished on GRAIN were higher when compared to RG/GRAIN or RG regimens (P < 0.05). Flavor intensity and beef flavor scores were higher (P < 0.05) for SL from GRAIN- or RG/GRAIN-finished steers compared to RG-finished steers. GRAIN SL had lower (P < 0.05) WBSF values than RG, but similar (P > 0.05) to RG/GRAIN. Trained sensory tenderness and flavor scores and WBSF values for RE were not affected by finishing regimen (P > 0.05). GRAIN steaks had a higher consumer overall acceptability score, average price/kg, and rank (P < 0.05). While carcass, fat, and sensory disadvantages were present in RG cattle, the overall magnitude of the differences compared to GRAIN cattle was fairly small.