Effect of dietary inclusion of triticale dried distillers' grain and oilseeds on quality and fatty acid profile of meat from feedlot steers

This study compared carcass, meat quality and fatty acid profiles of longissimus thoracis (LT) from feedlot cattle fed barley grain with or without oilseed (OS). Six diets containing no oilseed (No-OS), 10% ground flaxseed (FS), 10% high oleate sunflower seeds (SS) with or without 30% triticale dried distiller's grain (DDGS) were prepared. Feeding DDGS increased chroma at 24 and 144 h post mortem. Feeding FS increased weight% of LT PUFA (P < 0.05) compared to No-OS or SS. An OS by DDGS interaction occurred for 18:3n − 3 (P < 0.05) where FS increased weight% of 18:3n − 3 (P < 0.05), a response accentuated (P < 0.05) by DDGS. Feeding DDGS increased weight% of LT 18:2n − 6 (P < 0.05), but neither OS nor DDGS affected conjugated linoleic acid (CLA, t7,c9 & c9,t11-18:2). Feeding FS increased weight% of n − 3 FA, and both FS and SS increased t10-18:1 with no effect on CLA or t11-18:1. Combination feeding of DDGS and FS further increased weight% of n − 3 FA and tempered increases in t10-18:1 with no effect on CLA or t11-18:1. The findings suggest a new strategy to increase beef omega-3 fatty acids efficiently through inclusion of a combination of DDGS and FS in feedlot diet.     

Oxidative changes of fresh loin from pig,caused by dietary conjugated linoleic acid and monounsaturated fatty acids,during refrigerated storage

Three levels (0%, 1% and 2%) of a conjugated linoleic acid enriched oil (CLA) were combined with two levels of monounsaturated fatty acids (MUFA) (19% and 39% average) for pig feeding. Changes in instrumental colour, lipid oxidation (thiobarbituric acid reactive substances, TBARS) and volatile profile of fresh loin chops, as affected by dietary CLA, MUFA and CLA × MUFA, were studied throughout 7 days of refrigerated storage. Lightness (L∗) evolution was conditioned by dietary CLA, whereas changes in redness (a∗) and yellowness (b∗) were unaffected by dietary supplements. Dietary CLA at 2% led to higher TBARS values of loin chops at day 7 of refrigerated storage (p < 0.05), while MUFA supplementation and CLA × MUFA interaction did not affect lipid oxidation. Dietary CLA, MUFA or CLA × MUFA did not affect most volatile compounds of loin chops after 7 days of storage.     

Evaluating the ability to measure pork fat quality for the production of commercial bacon

This study was conducted to evaluate three fat quality measures to characterize the suitability of pork bellies for commercial bacon production. Bellies from six sources (A to F) and two weight ranges (4.5/5.5 kg and 5.5/6.4 kg) were sampled by randomly selecting 50 belly sets from commercial combos of pork bellies from each source. The fat on these 50 individual bellies was assessed for quality using three methods: an FTNIR spectrophotometer to predict iodine (IV) value, a Durometer to assess fat firmness, and a subjective fat quality score (FQS) to assess integrated values of fat color, firmness, oiliness, and wetness. Data show that the fat quality measures differed (P < 0.05) by pork belly source and weight class with significant interactions between the two. Bellies were subsequently manufactured into bacon and bacon slicing yield index varied significantly (P < 0.05) by belly source, weight class, and their interaction. Durometer and FQS results were significantly (P < 0.05) correlated with bacon slice yield. The 50 belly subsamples obtained from each source/weight class also allowed the prediction of frequency distribution-based values based on fat quality measures (proportion IV > 74, proportion Durometer value < 50, and proportion FQS > 3. These were also correlated with slice yield. The data lead to a new paradigm model that is useful to describe both the uncertainty in fat quality measures and the relationships observed from pork bellies from different sources.     

Dietary CLA alters intramuscular fat and fatty acid composition of pig skeletal muscle and subcutaneous adipose tissue

The present study was conducted to determinate the responsiveness of different levels of dietary conjugated linoleic acid (CLA) on intramuscular fat (IMF) and fatty acid composition of skeletal muscle and fat in pigs fed from 59.5 to 133.5 kg. Forty female Large White × (Large White × Landrace) pigs were used. Four levels (0%, 0.5%, 1% and 2%) of a commercial enriched CLA oil supplementation (60% of CLA isomers, 30% cis-9, trans-11 and 30% trans-10, cis-12) were fed to pigs. Carcass, ham, foreleg and loin weights were recorded. Dietary CLA enrichment increased the loin weight (P < 0.01) and the combined weights of hams + forelegs + loins (P < 0.02). IMF content in Longissimus dorsi was also increased by dietary CLA treatment (P < 0.001) and a linear response was observed. Dietary CLA increased saturated fatty acids (SFA) and decreased monounsaturated fatty acids (MUFA) in muscle and adipose tissue (P < 0.001). Feeding 1% CLA to finishing swine increases IMF in heavy pigs slaughtered at an average weight of 133.5 kg.     

Low-fat frankfurters enriched with n−3 PUFA and edible seaweed: Effects of olive oil and chilled storage on physicochemical,sensory and microbial characteristics

This article reports a study of the physicochemical, sensory and microbiological characteristics of low-fat (10%) and n−3 PUFA-enriched frankfurters as affected by addition of seaweed (5% Himanthalia elongata), partial substitution (50%) of animal fat by olive oil and chilled storage (41 days at 2 °C). The presence of seaweed improved water and fat binding properties, reduced (P < 0.05) lightness and redness and increased (P < 0.05) the hardness and chewiness of low-fat frankfurters enriched with n−3 PUFA. The effect of olive oil on those characteristics was less pronounced than that of seaweed. Replacing pork backfat with olive oil in frankfurters produced acceptable sensory characteristics, similar to control, while addition of seaweed resulted in less acceptable products, due mainly to the special flavour of the seaweed. Formulation and storage time affected the total viable count and lactic acid bacteria count. Frankfurters containing olive oil and seaweed had the highest total viable count from day 14 of storage, with lactic acid bacteria becoming the predominant microflora.     

The physicochemical and microbiological characteristics of pork jerky in comparison to beef jerky

This study was carried out to compare the physicochemical and microbiological characteristics of beef and pork jerky, prepared from whole muscle of beef semimembranosus (BSM), pork semimembranosus (PSM), pork longissimus dorsi (PLD), and pork psoas major (PPM). The BSM and PSM jerky had higher moisture content, and PPM jerky had lower water activity than other jerky samples during 30 days of storage at 25 °C (P < 0.05). Pork jerky samples had higher lightness value than beef jerky, while PSM jerky had higher pH value than other jerky samples (P < 0.05). The shear force and TBARS values of PPM jerky were higher than those of other jerky samples (P < 0.05). Saturated fatty acid (SFA, %) was significantly higher in the BSM jerky than others, while unsaturated fatty acid (UFA, %) was significantly higher in the PSM and PLD than BSM and PPM jerky samples (P < 0.05). The PPM jerky showed a significant increase in UFA (%) during storage, and a significantly decrease in microbial count after storage of 30 days (P < 0.05).     

Antioxidant activity of Carob fruit extracts in cooked pork meat systems during chilled and frozen storage

The purpose of this study was to evaluate the effect of adding condensed tannins in the form of non-purified (Liposterine^®) or purified (Exxenterol^®) extracts obtained from Carob fruit to prevent lipid cooked pork meat systems from oxidising during chilling and frozen storage. The antioxidant activity of these extracts was compared with that of α-tocopherol. Meat lipid alteration was evaluated as thiobarbituric acid reactive substances content (TBARS) and polar material-related triglyceride compounds followed by high-performance size-exclusion chromatography (HPSEC). TBARS levels were lower (P < 0.05) in samples containing Liposterine (LM), Exxenterol (EM), and α-tocopherol (TM) than in control sample (CM) under chilled storage. TBARS formation was similar (P > 0.05) for LM and EM but lower (P < 0.05) than for TM. Polar material increased several times in all samples, but significantly less in TM and EM than in LM. Thermal oxidation compounds determined by HPSEC were lower (P < 0.05) in EM than in LM or TM. The changes in polar material were proportionally smaller after six months frozen storage than after chilled storage, with Exxenterol displaying the highest antioxidant protection. Therefore Carob fruit extracts can be successfully used to reduce fat alteration in cooked pork meat at chilled and frozen temperatures.     

The effect of ractopamine hydrochloride (Paylean) on lean carcass yields and pork quality characteristics of heavy pigs fed normal and amino acid fortified diets

Effects of ractopamine hydrochloride (RAC) on carcass parameters in heavy weight (133.24 ± 8.07 kg) finishing pigs (n = 278) given amino acid fortified (AA) or 16% crude protein (CP) diets were evaluated. A total of seven experimental diets were formulated; RAC was added at 0, 5 and 20 ppm to the 16% CP diets (CP0, CP5 and CP20, respectively) and at 0, 5, 10 and 20 ppm to the AA fortified diets (AA0, AA5, AA10 and AA20, respectively). Carcass, tenderloin, and ham weights were heavier (P < 0.05) for RAC AA diets vs. AA0. Loin weight was heavier (P < 0.05) for AA20 vs. AA0 and CP20 vs. CP0. No differences (P > 0.05) were observed for color or firmness scores. Carcass muscle score, ham weight and protein% were greater (P < 0.05) for RAC diets. Moisture was greater (P < 0.05) and fat was lower (P < 0.05) for AA5 and AA20 vs. AA0 and CP5 and CP20 vs. CP0. Feeding RAC to late finishing swine increases carcass yields and protein% with lower fat% for pigs weighing up to 136 kg.     

Effect of ractopamine–HCl supplementation for 28 days on carcass characteristics,muscle fiber morphometrics,and whole muscle yields of six distinct muscles of the loin and round

This study evaluated the effects of ractopamine–HCl (RAC) supplementation on carcass characteristics, muscle fiber morphometrics, and tenderness. Thirty-four steers (2 groups, 4 replicates) were fed RAC or carrier for 28 days prior to harvest. Seventy-two hours postmortem, the Longissimus lumborum (LL), Gracilis (GRA), Vastus lateralis (VL), Rectus femoris (RF), Semimembranosus (SM), and Adductor (ADD) were dissected from each carcass. Commodity weight, denuded weight, and muscle dimensions were collected. RAC supplementation tended to affect dressing percentage (P = 0.15) and muscle firmness (P < 0.15), and significantly affected lean maturity (P < 0.05) and marbling score (P < 0.05). With the exception of the LL and GRA (P < 0.05), RAC had no effect on muscle dimensions. RAC did not influence the tenderness of vacuum-packaged, aged steaks as measured by Warner–Bratzler shear force. Muscle fiber size within the six muscles was unchanged (P > 0.05) by RAC. Thus, RAC improves carcass parameters without a negative impact on tenderness.     

Oxidative stability and total lipids on thigh and breast meat of broilers fed diets with two fat sources and supplemented with conjugated linoleic acid

Two hundred broiler chickens of 21 days of age were distributed in a completely randomized factorial arrangement 2×5 (two oil sources, i.e. soybean or canola oil and five levels of CLA supplementation, i.e. 0.0%, 0.25%, 0.50%, 0.75% and 1.00%). The purpose of this study was to evaluate the dietary supplementation of broiler diets with CLA and oil sources on the lipid content and on the oxidative stability of chicken meat submitted to refrigeration or freezing storage temperatures. The use of canola oil and increasing CLA levels resulted in a linear reduction (P<0.05) on the total lipids in breast meat. These results can explain a linear reduction (P<0.05) observed in the malonaldehyde content of refrigerated and frozen meat of birds receiving canola oil. Birds receiving soybean oil and supplemented with CLA showed an abrupt reduction of total lipids on breast meat from 0.89 g/100 g at 0% CLA to 0.36 g/100 g at 0.5% CLA followed by a small increase at higher levels of CLA (P<0.05). These observations may help to explain the reduction (P<0.05) of oxidation in breast meat during frozen storage at 50 and 100 days as well as during cold storage at 5 °C.     

Practical use of surimi-like material made from porcine longissimus dorsi muscle for the production of low-fat pork patties

This study evaluates the effect of replacing fat with surimi-like material (SLM) made from the porcine longissimus dorsi muscle on the physicochemical and sensory characteristics of pork patties. Pork patties were produced with different levels of fat and SLM using a commercial method. Pork patties produced with 20% SLM had the lowest fat content (1.76%, P < 0.001), and had a higher cooking yield (87.41 vs. 78.57%, P < 0.05) and less shrinkage (4.01 vs. 9.02%, P < 0.001) than patties produced with 20% back-fat (control). Moreover, patties produced with SLM exhibited more acceptable organoleptic characteristics, including tenderness (P < 0.01) and overall acceptability (P < 0.001), than full-fat control patties. These results indicated that SLM cannot only be used as a fat replacer, but that it also improves the physicochemical and sensory characteristics of low-fat pork patties.     

Chemical composition characteristics of the longissimus and semimembranosus muscles for pigs from New Zealand and Singapore

A range of composition characteristics of the longissimus (LL) and semimembranosus (SM) muscles were compared between pigs raised in intensive and extensive production systems in New Zealand (NZ), and pigs raised in an intensive system in Indonesia for supply to the Singapore market (n = 8/group). Ultimate pH was slightly higher for the Singaporean LL muscles (P < 0.05), while LL muscle of the NZ extensive group was redder (higher a^∗ values) and contained more fat (P < 0.05). Muscle iron levels were highest for the NZ extensive group and lowest for a lighter group within the Singapore pigs (P < 0.05). Differences in fatty acid concentrations, which were also measured in a sample of the belly cut, could largely be attributed to the effects of diet, with higher levels of alpha linolenic acid for the NZ extensive group (P < 0.05) due to linseed in the diet, and much higher levels of linoleic acid and the P:S ratio for the Singapore group (P < 0.05). Some statistically significant differences in amino acid concentrations were shown between muscles and groups, but they were not large. With respect to compounds with potential bioactive properties, coenzyme Q_10, and taurine levels were higher in pork from NZ pigs, and carnosine levels were highest for the NZ intensive group (P < 0.05). The LL muscle contained more coenzyme Q₁₀ and taurine, but less carnosine than the SM muscle (P < 0.001). It is concluded that some of these composition differences in the pork from the muscles and groups compared may be of commercial importance, but several are likely to have been due to dietary or weight differences.     

Effect of processing and storage of Jameed on conjugated linoleic acid content and fat and cholesterol oxidation

The influence of Jameed processing and storage on fat and cholesterol oxidation, hydrolytic rancidity, and conjugated linoleic acid (CLA) was evaluated by determining peroxide value (PV), 7-ketocholesterol, free fatty acids content (FFAs) and total CLA. Three different sizes of Jameed pieces (ca. 50, 200 and 400 g balls) were used to investigate the influence of storage for 0, 1, 3, 5 and 7 months on the above lipid oxidation parameters. No significant (P>0.05) effect of the Jameed processing steps on lipid changes was found with the exception of the sun drying steps, that caused an increase of PV, 7-ketocholesterol and FFA contents and a decrease in CLA content. This trend was also observed during storage of Jameed at room temperature and kept exposed to light and atmospheric air. The PV values of the 50, 200 and 400 g balls after 7 months of storage were 35.3, 19.4 and 20.4 meq O₂ kg⁻¹ of fat, that were 17, 11 and 12 times higher compared with the corresponding values of the fresh samples (1.9 meq O₂ kg⁻¹ of fat ). The 7-ketocholesterol of the tested samples increased from about 5.7 μg g⁻¹ to 210, 120 and 125 μg g⁻¹ for the 50, 200 and 400 g balls, respectively. FFA content increased remarkably during storage, from about 1.3 g kg⁻¹ at the beginning of storage to 8.6 g kg⁻¹ of fat after 7 months with no significant (P>0.05) effect for the size of Jameed pieces on FFAs content. On the contrary, a decrease of about 43%, 26% and 26% of the original value (5.7 mg kg⁻¹ of fat) in CLA content was found for the stored Jameed pieces of 50, 200 and 400 g, respectively.     

Effect of hot-boned pork on the quality of hurdle treated pork sausages during ambient temperature (37 ± 1 °C) storage

The study was aimed at evaluating the suitability of hot-boned pork and pork fat for processing shelf-stable pork sausages using hurdle technology and the different hurdles incorporated were low pH, low water activity, dipping in potassium sorbate solution, vacuum-packaging and post-package reheating. Emulsion stability and cooking yield did not Izatnagardiffer significantly among hot- and cold-processed sausages. Despite the same emulsion pH, the sausages from hot-boned pork had significantly higher fat content. Colour and texture profiles of pork sausages were significantly (P < 0.05) influenced by hot processing. During storage at ambient temperature (37 ± 1 °C), various physico-chemical characteristics, namely pH, TBARS and tyrosine values, of hot- and cold-processed sausages, did not differ. Hot-processing markedly increased the total plate counts of the sausages, but a significant difference was absent for anaerobic counts between treatments at any particular storage interval. Cold-processed sausages had the higher lactobacillus counts throughout the storage period. Sensory evaluation revealed that hurdle-treated pork sausages from hot-boned pork were equally suitable as those from cold-boned pork up to day 6 at ambient temperature.     

Comparison of wheat- versus corn-based dried distillers’ grains with solubles on meat quality of feedlot cattle

A considerable amount of information has been generated on the feeding value and impact of corn dried distillers’ grains with solubles (DDGS) on meat quality, whereas little is known about the effects of wheat DDGS on meat quality, and no direct comparison of these two sources of DDGS has been completed. The current study was conducted to examine the objective and subjective carcass and meat quality traits of cattle fed diets containing corn or wheat (20% or 40%) DDGS (DM basis) as compared to a standard barley-based finishing diet (control). In general, meat obtained from animals fed the barley-based control diet was slightly darker in colour (lower chroma and hue at 24 h, P < 0.01) and less tender (highest proportion of tough shears at 2 d and lowest proportion of tender shears at 20 d). Meat from corn DDGS was rated as more tender and palatable than control samples (P < 0.05), and 20% corn samples were rated better for beef flavour intensity (P < 0.01) and desirability (P < 0.05) than 40% corn DDGS samples. In contrast, meat from steers fed wheat DDGS showed intermediate characteristics between steers fed control and corn DDGS diets. Hence, feeding wheat DDGS had no negative effects, and feeding corn DDGS had some positive effects on meat quality characteristics of beef.     

Quality and consumer acceptability of salt and phosphate enhanced goat loin from goats fed varying levels of pine bark

Goat loins (n = 22) were evaluated to test effects of 0, 15, and 30% dietary pine bark (PB) and salt, water, and phosphate enhancement on shelf-life, shear force (WBSF) and consumer acceptability. No interactions existed between PB and enhancement. Dietary PB did not affect objective color, but enhancement increased a* and b* values (P < 0.05). Thiobarbituric acid reactive substances (TBARS) increased from d 1 to d 5 of storage (P < 0.0001), but were not affected by PB or enhancement. The WBSF for 30% PB was less than that of 0% PB (P = 0.0199), and enhancement decreased WBSF (P = 0.0010). Texture, flavor, and overall acceptability were greater (P < 0.05) for 15 and 30% PB compared to 0% PB. Enhanced loin samples had greater appearance, aroma, texture, flavor, and overall acceptability scores (P < 0.05). Results indicated that enhancement improved tenderness and consumer acceptability of goat loin, and PB had minimal impact on goat loin quality.     

The feeding value of corn distillers solubles for lactating dairy cows

Fifteen Holstein cows (10 multiparous and 5 primiparous) in early to mid lactation (79.3 ± 9.2 d in milk) were used in a multiple 5 × 5 Latin square design with 4-wk periods to evaluate and compare the use of condensed corn distillers solubles (CCDS) and dried distillers grains with solubles (DDGS) in the total mixed ration. The forage portion of the diets was kept constant at 27.5% corn silage and 27.5% alfalfa hay (dry matter basis). Diets were 1) 0% distillers grains products (control); 2) 18.5% DDGS; 3) 10% CCDS; 4) 20% CCDS; and 5) a combination diet of 18.5% DDGS with 10% CCDS. Diets 2 and 3 contained 2% fat from DDGS or CCDS, whereas diet 4 contained 4% fat from CCDS and diet 5 contained 4% fat from the blend of DDGS and CCDS. The diets were balanced to provide 17% crude protein with variation in acid detergent fiber, neutral detergent fiber, and fat concentration. Dry matter intake (21.5 kg/d) was similar for all diets. Milk yield (33.8, 36.2, 35.5, 36.0, and 36.0 kg/d) tended to be greater for diets 2 to 5 than for diet 1, whereas yields of fat (1.04 kg/d), protein (1.02 kg/d), fat percentage (2.94), and protein percentage (2.98) were similar for all diets. Energy-corrected milk (32.2 kg/d) and feed efficiency (1.58 kg of energy-corrected milk/kg of dry matter intake) were similar for all diets. Milk urea nitrogen (15.0, 10.9, 11.1, 11.0, and 11.4 mg/dL) as well as blood urea nitrogen (15.6, 12.5, 14.6, 13.8, and 14.2 mg/dL) were decreased in diets 2 to 5 compared with diet 1. Milk concentrations of long-chain fatty acids as well as polyunsaturated fatty acids were greater and medium-chain fatty acid concentrations were lower for diets 2 to 5 compared with diet 1. Concentrations of cis-9, trans-11 conjugated linoleic acid (CLA; 0.33, 0.68, 0.51, 0.85, and 1.07 g/100 g of fatty acids) as well as trans-10, cis-12 CLA (<0.01, 0.01, <0.01, 0.02, and 0.02 g/100 g of fatty acids) were greater for diets 2 to 5 compared with diet 1. Molar proportions of ruminal acetate decreased and propionate increased for diets 2 to 5 compared with diet 1. The results showed that CCDS is as effective as DDGS in replacing soybean meal and corn grain in the total mixed ration.     

Influence of meat exudates on the quality characteristics of fresh and freeze-thawed pork

The influence of the accumulated exudates released from pork loin of itself on the quality characteristics of fresh and freeze-thawed pork during cold storage was investigated. Pork loins were divided into four groups (fresh pork with exudates, fresh pork without exudates, freeze-thawed pork with exudates and freeze-thawed pork without exudates) and stored at 1.0 °C for 7 days. Exudate amount increased due to freeze-thawing and with storage, and most quality traits such as drip loss, cooking loss, tenderness, lightness, redness, and moisture content were affected by freeze-thawing (p < 0.05). Freeze–thaw increased drip loss but decreased moisture content, cooking loss, tenderness, lightness and redness of meat (p < 0.05). Microbial growth was solely affected by exudate removal and the removal of initial exudates decreased microbial growth (p < 0.05). Exudates were positively correlated with total protein content and total plate count but negatively correlated with pH and cooking loss. Therefore, removing meat exudates and avoiding freeze can slow down the quality deterioration of pork during cold storage.     

Volatile compounds of fresh and dry-cured loin as affected by dietary conjugated linoleic acid and monounsaturated fatty acids

Three levels (0%, 1% and 2%) of an enriched conjugated linoleic acid oil (CLA) were combined with two levels of monounsaturated fatty acids (MUFA) (low (19%) average and high (39%) average) for pig feeding. The profile of volatile compounds of fresh and dry-cured loin as affected by dietary CLA, MUFA and CLA × MUFA interaction was studied by headspace-solid phase microextraction coupled to gas chromatography–mass spectrometry. A total of 27 and 69 compounds were identified in fresh loin and dry-cured loin, respectively. Identified compounds were alcohols, aldehydes, aliphatic hydrocarbons, aromatic hydrocarbons, esters, furans, ketones, nitrogen compounds, sulphur compounds and terpenes. No qualitative differences in volatile compounds caused by the assayed treatments were found neither in fresh loin nor in dry-cured loin. Dietary CLA, MUFA and their interaction did not affect the level of most detected volatiles. Nevertheless, in fresh loin, the level of heptanal significantly increased due to dietary CLA (p = 0.001) and the area units (AU) for ethyl benzene and 1,3-dimethyl benzene increased at 1% CLA (p < 0.05). In the case of dry-cured loin, the AU of heptanal, nonanal and 2-nonenal contents increased due to dietary CLA (p = 0.016, 0.024 and 0.019, respectively).