Effect of concentrate feeding on instrumental meat quality and sensory characteristics of fallow deer venison

Venison from twenty four hybrid fallow deer does, 36 months old with an initial body condition score (BCS) of 2, was tested to determine the influence of feed type on meat quality. Feeding with concentrates increased BCS (P < 0.01) but did not affect ultimate pH (P > 0.05). BCS 4 animals had higher intra muscular fat (IMF) (P < 0.01), and more tender meat (P < 0.05). Venison from does fed over 24 weeks exhibited less redness (P < 0.01) than those fed for 19 weeks regardless of feed type.Panellists evaluated samples for colour, flavour, tenderness, juiciness and overall liking. They detected significantly (P < 0.05) stronger flavour in meat from animals fed concentrates. Male panellists detected flavour differences within meat from animals fed concentrates (P < 0.05), with longer feeding periods resulting in stronger flavour. There was no difference in overall liking, therefore finishing fallow deer on grain-based concentrate feeds prior to slaughter provided little commercial advantage.     

Consumer evaluation of venison sensory quality: Effects of sex,body condition score and carcase suspension method

Intact fallow bucks (n = 20) and non-pregnant fallow does (n = 24) (Dama dama), in the body condition score (BCS) of 2, 3 and 4 (lean, prime and fat) and rising 2 year old red deer stags (n = 26) (Cervus elaphus) of the same BCS range (2–4) were used in this study to determine the impact of sex, BCS and method of carcase suspension on consumer perception of venison quality. Consumers were asked to evaluate cooked meat samples (M. gluteus medius) on an unstructured line scale for colour, flavour, tenderness, juiciness and overall liking. Meat from both fallow deer and red deer was preferred by consumers when carcases had hung by the pelvic suspension (PS) method compared with the Achilles tendon (AT) method of hanging (p < 0.001). Consumers also noted a difference in colour between sexes in fallow deer venison, with venison from 36 month-old does being darker (p = 0.015), and preferred venison from does over 18–24 month-old bucks. There was a significant difference in the consumer scores for tenderness in red deer stags of BCSs 2 and 4 (p = 0.05) with panellists determining BCS 4 animals to be more tender; however no tenderness differences were observed for fallow deer does compared with bucks.     

Rate of blood loss and timing of exsanguination on prevalence of ecchymosis in fallow deer (Dama dama)

Blood loss associated with four combinations of stunning and exsanguination methods was determined as part of studying prevalence of ecchymosis in slaughtered fallow deer (Dama dama). A fifth treatment simulated incomplete severance of the extended neck after captive bolt stunning. Predicted mean weights of blood collected from the five slaughter treatments, including electrical stunning followed by the thoracic stick method of exsanguination, captive bolt stunning followed by the thoracic stick, captive bolt stunning followed by the gash cut method of exsanguination, electrical stunning followed by the gash cut, and captive bolt stunning followed by incomplete severance of the extended neck, were 1458.7, 1072.7, 684.5, 463.7, and 228.5 g, respectively. The overall effect of exsanguination method was highly significant (p < 0.001) with the thoracic stick resulting in the greatest weight of blood collection in the 10 s period immediately after initiation. The overall effect of stunning method on blood loss was not significant, although there was a significant (p < 0.05) stunning method by exsanguination method interaction. Ecchymosis of varying severity occurred in some carcases from all treatment groups. Using the total loin and round ecchymosis scores, when little or no ecchymosis (grades 0 or 1) was compared with some ecchymosis (?grade 2) by logistic regression, castrated bucks were 9.8 times more likely (p = 0.002) and does 4.2 times more likely (p = 0.06) to have some ecchymosis than entire bucks. The results indicate that ecchymosis can be reduced in fallow deer carcases by thoracic stick exsanguination incorporated less than 10 s after stunning.     

Real-time PCR for detection and quantification of red deer (Cervus elaphus), fallow deer (Dama dama), and roe deer (Capreolus capreolus) in meat mixtures

A rapid real-time polymerase chain reaction (PCR) technique using SYBR Green detection system, has been developed for the quantification of red deer, fallow deer, and roe deer DNAs in meat mixtures. The method combines the use of cervid-specific primers that amplify a 134, 169, and 120 bp of the 12S rRNA gene fragment of red deer, fallow deer and roe deer, respectively, and universal primers that amplify a 140 bp fragment on the nuclear 18S rRNA gene from eukaryotic DNA. The C_t (threshold cycle) values obtained with the 18S rRNA primers are used to normalize those obtained from each of the cervid-specific systems, serving as endogenous control for the total content of PCR-amplifiable DNA in the sample. Analysis of experimental raw and heat treated binary mixtures of red deer, fallow deer or roe deer meat in a swine meat matrix demonstrated the suitability of the assay for the detection and quantification of the target cervid DNAs in the range 0.1–0.8%, depending on the species and treatment of the meat samples analyzed.     

Seasonal variation in red deer (Cervus elaphus) venison (M. longissimus dorsi) drip loss,calpain activity,colour and tenderness

Sixty four young red deer (Cervus elaphus) stags (< 2 years old) were slaughtered at four different times (December (Group 1); n = 17, March (Group 2); n = 8, July (Group 3); n = 20 and September (Group 4); n = 19) to evaluate seasonal effects on venison quality. M. longissimus dorsi samples for calpain analysis were collected on the slaughter line and the rest of these muscles were collected at 1 day post-slaughter. Loins were divided into four parts and randomly allocated to storage for 1 day, 3, 9 or 14 weeks at −1.5 °C and then vacuum packaged. Seasonal variation was demonstrated in venison pH. Highly significant positive regressions were found for shear force (P < 0.001) and colour display life (P < 0.001) on pH, where higher pH values were associated with tougher venison and longer colour display life. A clear trend of increasing fluid loss during storage, calculated as amount of purge at 14 weeks of storage minus the amount of drip loss at 1 day post-slaughter, was evident, averaging 2.5% (SEM 0.17) over the four groups. The relative activities of the calpastatin-bound calpain, μ-calpain and m-calpain all exhibited a seasonal pattern although there was no evidence (P > 0.05) that this affected tenderness. There was a highly significant (P < 0.001) negative regression for the average over the four storage times of drip and purge on calpastatin-bound calpain activity.     

Carcass quality in male fallow deer (Dama dama): effects of age and supplementary feeding

Thirty-two male fallow deer, half 18- and half 30-month-old, were slaughtered after a 4-month feeding trial on pasture alone or with daily supplement of 500 g (dry matter) concentrate/head (eight each 18- and 30-month-old). The concentrate was composed of 40% maize, 25% sugar beet pulp, 20% alfalfa, 13% soy flakes, 2% minerals and vitamins. Supplemented deer were heavier (49.9 vs 45.0 kg) and their carcasses produced higher dressing proportions (61.5 vs 57.2%) and bigger amounts of first quality cuts. Supplemented feeding improved muscle development and fat deposition. Thirty-month-olds were heavier than 18-month-olds (53.3 vs 41.6 kg) and their carcasses produced higher dressing proportions (60.9 vs 57.7%) and bigger amounts of first quality cuts; older deer carcasses showed better conformation and bigger amounts of fat deposition.     

Effect of muscle stretching on meat quality of biceps femoris from beef

The objective of this study was to examine the effect of muscle stretching on meat quality and ultrastructure of biceps femoris (BF) from beef. After slaughter, the right side of the carcasses were suspended from the Achilles tendon (AS; n=10), while the left sides were re-hanged from the pelvic bone (PS; n=10). Meat quality was evaluated by water holding capacity (WHC), cooking loss (CL), color, shear force (SF) and sarcomere length (SL). As a result, PS had no impact on WHC, CL and color parameters. PS significantly decreased SF values by 7.5% only at 2 days postmortem. At pelvic suspended sides, SL was increased by 0.13 μm, 0.14 μm and 0.12 μm at 2, 7 and 10 days postmortem, respectively (P<0.001). Electron microscopy showed that the ultrastructure of BF have longer sarcomeres and smaller fiber diameter after PS. In conclusion, PS is a useful method for improving tenderness by stretching muscles.     

Microbiological quality and potential public health risks of export meat from springbok (Antidorcas marsupialis) in Namibia

To assess the microbiological quality and safety of export game meat; i) a total of 80 pooled meat samples for aerobic plate count (APC) and Enterobacteriaceae ii) water used in harvesting and processing for microbiological quality and iii) meat and rectal contents for Salmonella spp. and Shiga toxin Escherichia coli (STEC) were evaluated in 2009 and 2010. No differences (p > 0.05) in the APCs were observed between the years, but the mean Enterobacteriaceae count for 2009 was 1.33 ± 0.69 log₁₀ cfu/cm² compared to 2.93 ± 1.50 log₁₀ cfu/cm² for 2010. Insignificant Heterotrophic Plate Count (HPC) levels were detected in 9/23 field water samples, while fecal bacterial (coliforms, Clostridium perfringens and enterococci) were absent in all samples. No Salmonella spp. was isolated and all E. coli isolates from meat were negative for STEC virulence genes (stx1, stx2, eae and hlyA), suggesting a negligible role by springbok in the epidemiology of STEC and Salmonella.     

Assessment of spring habitat selection of red deer (Cervus elaphus L.) based on census data

Summary Data from 11 years of spring census over a 6,325 ha area were used to estimate the habitat preferences of red deer in the West Hertogenwald forest (Ardenne, Belgium). Each year, 1 to 4 censuses were organised to assess deer population density. The census method was based on a systematic coverage of the forest by experienced spotters. Each observation was described (number, sex, behaviour) and located in a GIS. Within the study area, 915 groups of non-antlered deer (hind, yearling and calf), corresponding to 2,775 individuals, were recorded during the 24 censuses of the period from 1990 to 2000. Different environmental variables describing the study area, such as forest cover (tree species and structure), canopy closure, altitude, distance to roads and pastures, were identified and integrated into the GIS. Each observation of a group of non-antlered deer was spatially related to these environmental variables to perform a habitat selection analysis. The results of this analysis showed significant preferences for certain forest types (eg spruce vs beech), and for open canopy areas. Positive correlations to high altitude areas, pastures and spruce thicket stages and a negative correlation to roads were high-lighted. A comparison procedure involving GPS-collared animals in the same area was performed and showed a good correlation between census and GPS data. The methodology of this approach and the management implications of the results are discussed.     

Proteolysis,physicochemical characteristics and free fatty acid composition of dry sausages made with deer (Cervus elaphus) or wild boar (Sus scrofa) meat: A preliminary study

In order to contribute to typifying delicatessen made with game meat, the proteolysis, physicochemical characteristic and free fatty acid composition were determined in 10 commercial dry sausages, chorizos and saucissons, made with deer or wild boar meat. The a_w and pH values were similar for all the samples; however, the results for dry matter, protein nitrogen, fat, ash, sodium chloride, phosphorus, and sodium nitrite content showed great variation among the samples tested. The myofibrillar protein content was higher than the sarcoplasmic protein content in all samples analysed. The electrophoretic profiles of sarcoplasmic and myofibrillar proteins were different among samples. Principal components analysis, run on the relative density of myofibrillar and sarcoplasmic proteins, separated the chorizo and saucisson samples. Chorizo samples were a homogeneous group in the analysis of myofibrillar proteins, which indicated similar proteolysis effects for all samples. The majority acids were oleic, palmitic, linoleic and stearic in all samples. Chorizos differed from saucissons in the greater quantity (P < 0.05) of polyunsaturated fatty acids.     

Fatty acid profile of meat (Longissimus lumborum) from female roe deer (Capreolus capreolus L.) and red deer (Cervus elaphus L.)

The aim of this study was to compare the fatty acid profile of intramuscular fat (IMF) in female roe deer (Capreolus capreolus L.) and red deer (Cervus elaphus L.) living in the wild. The experimental materials comprised samples of the Longissimus lumborum (LL) muscle collected from 20 carcasses of does aged 3–5 years and 15 carcasses of hinds aged 4–6 years. All animals were hunter-harvested in the forests of North-Eastern Poland. The IMF of does had considerably higher concentrations of monounsaturated and polyunsaturated fatty acids. Therefore, it was characterized by more desirable values of quality parameters, and provided more health benefits. The observed differences in the fatty acid composition of IMF between does and hinds are important in view of both the nutritional value of meat and its susceptibility to lipid oxidation and rancidification.     

Effect of two different red grape pomace extracts obtained under different extraction systems on meat quality of pork burgers

The effect on meat quality (pH, microbial spoilage, lipid oxidation and colour coordinates) of two different types of red grape pomace extracts obtained by different extraction systems [(Grape pomace extract I, GPI (methanolic extraction + High-Low Instantaneous Pressure – HLIP–GPI) and Grape pomace extract II, GPII (methanolic extraction, GPII) at 0.06 g/100 g final product concentration] in pork burgers packed under aerobic conditions (4 °C) was assessed at 0, 3 and 6 days post-storage.Based on the results the highest colour stability, lipid oxidation inhibition and the best global acceptability after 6 days of storage (data not shown) observed in burgers added with the GPI indicate that the new extraction system (HLIP) developed could be a valid alternative to optimize the purity of the grape pomace extracts in order to use them as preservative in meat foodstuffs.     

Effect of gender on the meat quality characteristics and chemical composition of kudu (Tragelaphus strepsiceros), an African antelope species

The kudu (Tragelaphus strepsiceros), one of Africa’s most majestic antelope species, shows a strong sexual dimorphism. The male reaches a larger size (≈250 kg live weight) than the female (≈180 kg live weight). Kudu occur throughout the savannah regions in central Africa, south of the equatorial forests, through East Africa to Ethiopia, Sudan and Chad down to the Eastern Cape (South Africa). Kudu are predominantly browsers, but will occasionally graze. Within South Africa, this species is hunted regularly for local consumption, and Kudu meat is also a regular item in most restaurants that serve game meat and is also frequently exported. However, very little data has been published pertaining to the muscle chemical composition and other quality attributes of its meat. In the present investigation, the proximate, amino acid, fatty acid and mineral chemical compositions of the Longissimus dorsi et lumborum muscle of 18 animals are presented, and the effect of gender thereupon tested by means of standard student’s t-tests. Kudu meat has a high protein and a low fat content. Only two of the longer chained polyunsaturated fatty acids (C20:3n−6 and C20:5n−3) differed between the females and males, the latter having a higher concentration each time. Of the kudu muscle’s fatty acids, 37% were saturated, 22% monounsaturated and 41% polyunsaturated. The mean PUFA to SFA ratio (1.12) was well above the recommended 0.45 prescribed by the British Department of Health. The n−6:n−3 PUFA ratio (2.34) was also well below the British Department of Health’s recommended figure of four. Histidine and valine had significantly higher levels in female kudu meat than in male kudu meat. Phosphorus was present at the highest concentrations in both female and male animals. Overall, the chemical composition of kudu meat is not significantly effected by gender.     

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.     

Effect of diet,slaughter weight and sex on instrumental and sensory meat characteristics in rabbits

The effect of the fattening diet, slaughter weight and sex on meat quality was studied in a total of 156 hybrid rabbits. After weaning, rabbits were divided into three groups of 52 animals each (50% male and 50% female), that were allocated for three weeks to one of three commercial diets containing low (14.28%, A), medium (18.04%, B) and high (20.48%, C) fibre content with decreasing energy levels. Animals were slaughtered at 2.0 and 2.3 kg after the consumption of a common pre-slaughter non-medicated concentrate and pH, colour, water-holding capacity (WHC), Warner–Bratzler shear test and sensory analysis were all measured. Meat from animals fed with low fibre and high energy was the least luminous. Rabbits slaughtered at 2.0 kg showed more yellowness than at 2.3 kg at 0 min. In both traits, these differences did not prevail after 15 min of blooming. Globally, meat from males was more coloured than that of the females, both at 0 and 15 min of blooming. No significant differences were found for pH, WHC or shear test for the individual effects. In the sensory analysis, rabbit and grass odours were more intense at 2.0 kg than at 2.3 kg of slaughter weight.     

A review of the growth, and of the carcass and meat quality characteristics of the one-humped camel (Camelus dromedaries)

The dromedary camel is a good source of meat especially in areas where the climate adversely affects the performance of other meat animals. This is because of its unique physiological characteristics, including a great tolerance to high temperatures, solar radiation, water scarcity, rough topography and poor vegetation. The average birth weight of camels is about 35kg, but it varies widely between regions, breeds and within the same breed. The meat producing ability of camels is limited by modest growth rates (500g/day). However, camels are mostly produced under traditional extensive systems on poor levels of nutrition and are mostly slaughtered at older ages after a career in work, racing or milk production. Camels reach live weights of about 650kg at 7-8 years of age, and produce carcass weights ranging from 125 to 400kg with dressing-out percentage values from 55% to 70%. Camel carcasses contain about 57% muscle, 26% bone and 17% fat with fore halves (cranial to rib 13) significantly heavier than the hind halves. Camel lean meat contains about 78% water, 19% protein, 3% fat, and 1.2% ash with a small amount of intramuscular fat, which renders it a healthy food for humans. Camel meat has been described as raspberry red to dark brown in colour and the fat of the camel meat is white. Camel meat is similar in taste and texture to beef. The amino acid and mineral contents of camel meat are often higher than beef, probably due to lower intramuscular fat levels. Recently, camel meat has been processed into burgers, patties, sausages and shawarma to add value. Future research efforts need to focus on exploiting the potential of the camel as a source of meat through multidisplinary research into efficient production systems, and improved meat technology and marketing.     

Effect of a supplementation of Euphorbia heterophylla on nutritional meat quality of Guinea pig (Cavia porcellus L.)

The aim of the present work was to study the effect of dietary supplementation of Euphorbia heterophylla on the quality of the Guinea pig meat. Forty guinea pigs were divided into two groups fed ad libitum during 46 days a Panicum maximum diet (Panicum diet) or a mixed diet (75% Panicum maximum + 25% Euphorbia heterophylla) (Paneuphorbia diet) to compare their effects on performances and on the composition of guinea pig tissues and carcass. Daily weight gain, liver weight, carcass yield, and the lipid content of both the carcass and the perirenal fat were significantly increased by the Paneuphorbia diet. Feeding Paneuphorbia diet increased (P < 0.05) the n-3 PUFA content in perirenal fat, muscle, liver and in the carcass and decreased (P < 0.05) the n-6/n-3 ratios in all these tissues and the carcass. In conclusion, this study shows that Euphorbia heterophylla is a source of n-3 fatty acids which can improve significantly the n-3 PUFA content of Guinea pig meat and carcass.     

The bacterial quality of red meat and offal in Casablanca (Morocco)

The present study aimed to evaluate the bacteriological quality of beef (n = 52), lamb (n = 52) and beef offal (n = 52) marketed in Casablanca, Morocco. Meat and offal samples (n = 156), were collected randomly from butcheries, supermarkets, and slaughterhouses. Two sampling periods were considered, one during the hot season and the second one during the cold season. The samples were analyzed for the presence of the following bacteria: Escherichia coli, coagulase-positive Staphylococcus, Clostridium perfringens, Salmonella, and Listeria monocytogenes. Results indicated that counts of the aerobic plate count, and fecal coliforms were particularly high in all the samples analyzed. E. coli, coagulase-positive Staphylococcus and C. perfringens were detected in 37.8, 16, and 4.5% of the meat samples, respectively. Neither Salmonella nor L. monocytogenes were isolated from meat samples. Approximately 26.9% of beef, 34.6% of lamb and 28.8% of beef offal samples contained bacteria above the maximum limits established by the Moroccan regulatory standards for meat and meat products. Seasonality and the distribution location significantly (p < 0.05) affected bacterial populations: the hot season and butcheries appeared to be cases where the highest populations of bacteria in meat were observed. These high levels of microbiological contamination attest the poor hygienic quality of meat and offal, possibly due to uncontrolled processing, storage, and handling of these products.     

Genotypic effects of the Texel Muscling QTL (TM-QTL) on meat quality in purebred Texel lambs

Texel Muscling QTL (TM-QTL) increases loin muscling in lambs inheriting it from their sire only. This study investigated TM-QTL effects on meat quality in 209 Texel lambs that were CT-scanned then slaughtered at 20weeks (carcasses aged for ~1week). Loin meat quality traits included: CT-measured muscle density (predicting intramuscular fat); mechanical tenderness using Volodkevich-type jaws or MIRINZ tenderometer; intramuscular fat; sensory eating quality (sub-sample of 40 lambs). Volodkevich tenderness was also measured in the leg (Vastis lateralis). TM-QTL genotypes were determined, giving 40 non-carriers (+/+), 70 heterozygotes-53 inheriting TM-QTL from the sire (TM/+) and 17 from the dam (+/TM), 34 homozygote TM-QTL lambs (TM/TM) and 65 uncertain. Multiple regression identified no genotype effects on meat quality. For MIRINZ-measured loin tenderness only, contrasts revealed a significant additive effect of TM-QTL (1.27kgF difference between homozygotes). However, the taste panel identified no significant differences between +/+ and TM/TM lambs. Results show little evidence of TM-QTL affecting meat quality.     

The effect of the Texel muscling QTL (TM-QTL) on meat quality traits in crossbred lambs

A quantitative trait locus (QTL) has been identified on chromosome 18 in Texel sheep (TM-QTL) that increases depth and area of the longissimus dorsi muscle. The study aimed to assess the pleiotropic QTL effects on key meat quality traits (toughness and intramuscular fat content after ?7 days aging) of crossbred lambs carrying one copy of the TM-QTL. The results showed that male Texel × Mule lambs carrying the TM-QTL had significantly less intramuscular fat (1.86% versus 2.25%) and higher toughness, with increased variation, in the loin muscle, compared to non-carrier males. Similar conclusions were obtained using two different types of tenderometer equipment: one using the Volodkevitch test (average shear force of 4.17 kgF or 40.9 N for carrier males, 2.61 kgF or 25.6 N for non-carrier males) and one using the MIRINZ test (average shear force of 6.18 kgF or 60.6 N for carrier males, 5.22 kgF or 51.2 N for non-carrier males). Although most toughness measurements were within published consumer acceptability limits, a few individual TM-QTL carrier lambs had unacceptably tough meat, despite enhanced post-slaughter processing. The TM-QTL did not significantly affect loin toughness in female lambs, leg toughness in either sex, or intramuscular fat content. These results should be considered, alongside direct effects of the TM-QTL on muscling and carcass composition, in recommendations for the use of this QTL by sheep breeders.