Meat Drip Loss Research Articles

Effects of Dietary Supplementation of Aqueous Extracts of Liriopeplatyphylla and Akebiaquinata on Breast Meat Qualities of Broiler Chickens

The present study investigated the effects of Liriopeplatyphylla extract (LPE) and Akebiaquinata extract (AQE) on breast meat properties when used as dietary supplements of broiler chickens. First, the identification and quantification of phenolic acids and flavonoids were carried out by HPLC. As a result, the total amount of phenolic acids and flavonoids was higher in AQE than LPE. These extracts were added at a rate of 0.2% to the broiler diets, and a feeding trial was conducted in battery cages for 35 d. At the end of the experiment (d 35), six carcasses from each treatments were used for evaluating meat quality. The experimental results indicate that color shades, pH levels, volatile basic nitrogen, thiobarbituric acid reactive substance (TBARS), cooking loss and drip loss of breast meat fed with 2 extracts were not different as compared with the controls at d 0 and d 10 of storage. However, TBARS values of breast meat fed with either the control diet or the LPE supplementation was increased as the storage period increased (from d 0 to d 10) (p<0.05), while AQE-fed groups were not different between d 0 to d 10 of storage. In textural properties, the addition of LPE and AQE decreased shear force values at d 10 of storage (p<0.05). Cohesiveness, gumminess and chewiness of breast meat were increased in AQE-fed groups when compared with the control at d 0 of storage (p<0.05). Dietary additions of AQE and LPE only increased the linoleic acid contents of chicken breast meat (p<0.05). In conclusion, supplementation of these extracts in broiler diets may potentially influence meat qualities including the TBARS, textural properties and linoleic acid levels in broiler chicken meats.

Effect of dietary betaine supplementation on the performance, carcass yield, and intestinal morphometrics of broilers submitted to heat stress

The objective of this study was to evaluate the effect of betaine in methionine- and choline-reduced diets fed to broilers submitted to heat stress. In total, 1,408 male broilers were randomly distributed into eight treatments, according to 2 x 4 (environment x diet) factorial arrangement, with eight replicates of 2 birds each. Birds were reared environmental chambers under controlled temperature (25-26 °C) or cyclic heat-stressing temperature (25-31 °C). The following diets were tested: positive control (PC), formulated to meet broiler nutritional requirements; negative control (NC), with reduced DL-methionine and choline chloride levels; and with two supplementation levels of natural betaine to the negative control diet (NC+NB1 and NC+NB2). Live performance, carcass traits, and intestinal morphometrics were evaluated when broilers were 45 days of age. The results showed that all evaluated parameters were influenced by the interaction between environment and diet, except for breast meat drip loss. The breakdown of the interactions showed that birds fed the PC diet and reared in the controlled environment had greater breast drip loss than those submitted to the cyclic heat-stress environment. Birds submitted to cyclic heat stress and fed the PC diet presented the lowest feed intake. Feed conversion ratio was influenced only by diet. The FCR of broilers fed the NC+NB2 diet was intermediate relative to those fed the PC and NC diets. The addition of betaine in the diet, with 11.18% digestible methionine and 24.73% total choline reductions, did not affect broiler live performance, carcass yield, or intestinal morphometrics.

Dietary alpha lipoic Acid improves body composition, meat quality and decreases collagen content in muscle of broiler chickens.

A total of 192 broiler chicks were used to evaluate the influence of dietary α-lipoic acid (ALA) on growth performance, carcass characteristics and meat quality of broiler chickens with the purpose of developing a strategy to prevent the occurrence of pale, soft, and exudative (PSE) meat and to improve the meat quality of broilers. At 22 d of age, birds were allocated to 4 ALA treatments (0, 400, 800, and 1200 ppm). The results showed that dietary ALA significantly decreased average feed intake (AFI), average daily gain (ADG), final live body weight (BW) and carcass weight (p<0.05), while no difference in feed conversion ratio (FCR) was detected among chickens fed with and without ALA. Abdominal fat weight significantly decreased (p<0.05) for broilers fed 800 and 1200 ppm ALA. However when calculated as the percentage of carcass weight there was no significant difference between control and ALA treatments. Meat quality measurements showed that dietary ALA regulated postmortem glycolysis and improved meat quality as evidenced by increased muscle pH and decreased drip loss of meat (p<0.05). Although ALA did not change the tenderness of meat as indicated by meat shear force, dietary ALA decreased collagen content and mRNA expression of COL3A1 gene (p<0.05). In conclusion, the results indicate that dietary ALA may contribute to the improvement of meat quality in broilers.

Effects of broccoli stem and leaf meal on broiler performance, skin pigmentation, antioxidant function, and meat quality

Three hundred sixty 1-d-old Ross 308 male broilers were used to study the effects of broccoli stem and leaf meal (BSLM) on growth performance, skin pigmentation, antioxidant function, and meat quality. The chicks were fed 4 diets containing different levels (0, 4.0, 8.0, and 12.0%) of BSLM as partial replacement for corn and soybean meal for a period of 42 d. The results showed that dietary supplementation of BSLM had no effect (P > 0.05) on growth performance. As compared with control, dietary 4%, 8%, and 12% BSLM increased (P < 0.05) b value (yellowness) both in shank and breast skin, increased (P < 0.05) the concentrations of xanthophylls in abdominal fat and breast skin, improved (P < 0.05) total antioxidant capability, lowered malondialdehyde concentration, and decreased drip loss percentage of breast muscle. Dietary 8% and 12% BSLM decreased (P < 0.05) shank L values (lightness), increased (P < 0.05) shank a value (redness), and increased (P < 0.05) the activities of superoxide dismutase and catalase of breast muscle as compared with control. The results indicated that dietary supplementation of BSLM in broiler chickens improved the poultry products quality with the more skin pigmentation and the less drip loss percentage of breast meat. The more skin pigmentation mainly related to the high amount of xanthophylls in BSLM. The decreased meat drip loss fed BSLM may be caused by the antioxidative function of BSLM.

Effects of dietary corn dried distillers grains with solubles and vitamin E on growth performance, meat quality, fatty acid profiles, and pork shelf life of finishing pigs

An experiment was conducted to study the effects of supplemental corn dried distillers grains with solubles (DDGS) and vitamin E on growth performance, meat quality, fatty acid profiles, and pork shelf life in finishing pigs. Forty-eight (58±2kg of BW) crossbred pigs (Duroc×Landrace×Large white) were randomly allotted to one of six dietary treatments in a 3×2 factorial arrangement, each treatment with eight replicates consisting of eight pigs. The dietary treatments included three DDGS levels (0, 15, and 30%) and two vitamin E levels (10 and 210IU/kg). No differences in average daily gain and gain to feed ratio were observed among treatments. However, average daily feed intake was decreased (P<0.05) with increasing levels of DDGS in the diets. Diets supplemented with high levels of vitamin E decreased shear force and drip loss of meat (P<0.05). Feeding diets containing DDGS decreased the proportion of saturated fatty acids (P<0.05), and increased the proportion of unsaturated fatty acids and polyunsaturated fatty acids (P<0.05) in adipose and muscle. Increasing dietary levels of vitamin E caused an increase in α-tocopherol concentration of plasma, liver, muscle, and adipose tissues (P<0.05). When longissimus muscle samples were vacuum-packaged and stored at 4°C, the concentration of total volatile basic nitrogen (TVB-N) in meat was increased with increasing levels of DDGS in diets and was decreased by the supplementation of vitamin E in diets. There was an increasing trend for thiobarbituric acid reactive substances (TBARS) when diets containing 15–30% DDGS were fed compared with corn–soybean meal-based diet. Especially on 13d of storage, the addition of DDGS in diets has a significant effect on TBARS value (P<0.05). However, supplementation with high levels of vitamin E in DDGS diets decreased TBARS value of meat on 4, 7, 10 and 13d (P<0.05) of storage. These data indicated that diets containing high levels of DDGS have some adverse effects on pork shelf life, supplementation with vitamin E can partially reverse these effects.

뽕잎 분말의 첨가 급여가 계육의 냉장저장 중 품질에 미치는 영향

본 시험은 육계 사료에 뽕잎 분말을 급여수준에 따라 5주간 사육한 육계의 pH, TBARS, VBN, 가열감량, 보수성 및 육즙손실을 조사하였다. 실험구는 뽕잎분말을 급여하지 않은 대조구, 뽕잎 분말 1% 급여구는 T1, 뽕잎 분말 2% 급여구는 T2, 그리고 뽕잎 분말 3% 급여구를 T3 등 4개 처리구로 나누어 사육한 후 10일간 냉장온도(<TEX>$4{\pm}1^{\circ}C$</TEX>)에서 저장하면서 실험하였다. 계육의 pH는 저장기간이 경과하면서 증가하였고, 뽕잎 분말의 급여는 대조구보다 낮았으며 급여량이 증가할수록 다소 낮아졌다. TBARS와 VBN은 저장기간이 지남에 따라 증가하였고, 뽕잎 분말 급여구에서 급여량이 증가할수록 낮아지는 결과로 뽕잎분말의 급여는 계육의 저장성을 개선하는 결과이었다. 가열감량은 저장기간이 경과하면서 감소하였고, 처리구간에는 유의성이 없었다. 육즙손실은 저장기간이 지남에 따라 증가하였으며, 뽕잎 분말의 급여는 육즙손실이 감소되는 경향이나 저장 7일과 10일에 유의성은 없었다(p>0.05). 결론적으로 뽕잎 분말 3%급여는 TBARS와 VBN이 감소되어 계육의 저장성을 개선할 가능성이 있는 것으로 판단된다. This study was investigated the effects of supplementation diets with mulberry leaves powder on pH, TBARS (thiobarbituric acid reactive substance) and VBN (volatile basic nitrogen) heating loss, WHC (water holding capacity), and drip loss of chicken meat. One hundred sixty broiler were fed diets for five weeks containing 0% mulberry leaves powder (Control), 1% mulberry leaves powder (T1), 2% mulberry leaves powder (T2), and 3% mulberry leaves powder (T3). At the end of this experiment, broiler were slaughtered, and stored at <TEX>$4^{\circ}C$</TEX> for 10 d. As storage time increased, all treatment groups resulted in increased pH, TBARS, VBN and drip loss (p<0.05). The TBARS and VBN were significantly decreased by the supplementation of mulberry leaves powder compared to the control (p<0.05). T3 results in much better TBARS and VBN than other treatment groups. Especially, T3 was significantly (p<0.05) more effective in improving self life compared to other treatment groups. Heating loss and drip loss were no significantly different among treatment group. In conclusion, these data indicate that supplementation of 3% mulberry leaves powder were most effective in decreasing TBARS and VBN.

Predicting quality and sensory attributes of pork using near-infrared hyperspectral imaging

Many subjective assessment methods for fresh meat quality are still widely used in the meat industry, making the development of an objective and non-destructive technique for assessing meat quality traits a vital need. In this study, a hyperspectral imaging technique was investigated for objective determination of pork quality attributes. Hyperspectral images in the near infrared region (900–1700nm) were acquired for pork samples from the longissimus dorsi muscle, and the representative spectral information was extracted from the loin eye area. Several mathematical pre-treatments including first and second derivatives, standard normal variate (SNV) and multiplicative scatter correction (MSC) were applied to examine the influence of spectral variations in predicting pork quality characteristics. Spectral information was used for predicting color features (L, a, b, chroma and hue angle), drip loss, pH and sensory characteristics by partial least-squares regression (PLS-R) models. Independent sets of feature-related wavelengths were selected for predicting each quality attribute. The results showed that color reflectance (L), pH and drip loss of pork meat could be predicted with determination coefficients (RCV2) of 0.93, 0.87 and 0.83, respectively. The regression coefficients from the PLS-R models at the selected optimal wavelengths were applied in a pixel-wise manner to convert spectral images to prediction maps that display the distribution of attributes within the sample. Results indicated that this technique is a potential tool for rapid assessment of pork quality.

The association between acyl-CoA synthetase (ACSL4) polymorphism and intramuscular fat content in (Landrace × Yorkshire) × Duroc pigs

The aim of the study was to check whether different genotypes at acyl-CoA synthetase (ACSL4 locus, SNP G2645A) are associated with pork quality. 132 (Landrace × Yorkshire) × Duroc fatteners were genotyped by originally developed PCR-RFLP method. Upon the slaughter, the samples of longissimus lumborum muscle were taken from each carcass to determine the following parameters: content of water, protein and fat, pH (45min, 24, 48, 96, and 144h post mortem), electrical conductivity, drip loss, meat lightness, glycolytic potential, glycogen and lactate contents in meat. Among several associations observed, the highly significant (p<0.01) was found for intramuscular fat (IMF) content. Pigs with genotype GG revealed the highest content of IMF — 2.47%.

Genetic variances, heritabilities and maternal effects on body weight, breast meat yield, meat quality traits and the shape of the growth curve in turkey birds

BackgroundTurkey is an important agricultural species and is largely used as a meat bird. In 2004, turkey represented 6.5% of the world poultry meat production. The world-wide turkey population has rapidly grown due to increased commercial farming. Due to the high demand for turkey meat from both consumers and industry global turkey stocks increased from 100 million in 1970 to over 276 million in 2004. This rapidly increasing importance of turkeys was a reason to design this study for the estimation of genetic parameters that control body weight, body composition, meat quality traits and parameters that shape the growth curve in turkey birds.ResultsThe average heritability estimate for body weight traits was 0.38, except for early weights that were strongly affected by maternal effects. This study showed that body weight traits, upper asymptote (a growth curve trait), percent breast meat and redness of meat had high heritability whereas heritabilities of breast length, breast width, percent drip loss, ultimate pH, lightness and yellowness of meat were medium to low. We found high positive genetic and phenotypic correlations between body weight, upper asymptote, most breast meat yield traits and percent drip loss but percent drip loss was found strongly negatively correlated with ultimate pH. Percent breast meat, however, showed genetic correlations close to zero with body weight traits and upper asymptote.ConclusionThe results of this analysis and the growth curve from the studied population of turkey birds suggest that the turkey birds could be selected for breeding between 60 and 80 days of age in order to improve overall production and the production of desirable cuts of meat. The continuous selection of birds within this age range could promote high growth rates but specific attention to meat quality would be needed to avoid a negative impact on the quality of meat.

Efeito da automatização nas diferentes estações do ano sobre os parâmetros de desempenho, rendimento e qualidade da carne de frangos de corte

This study had as objective to evaluate the effect of the handling system and season of the year on the performance and meat quality of broiler chicken. Five hundred twenty-four thousand commercial Cobb 500 chicks were allocated in three different handling systems, during the four seasons of the year. The experimental design was completely randomized, with a 3 x 4 factorial scheme (three types of storage shed and four seasons). The diet was provided by a co-operative system and consisted of rice straw, and the broilers were slaughtered in a slaughterhouse at 43 days of age. Feed intake, weight, daily weight gain and mortality rate were available with data provided by the co-operative system. Carcass defects were also evaluated, and analyses of pH, tenderness and drip loss of meat were determined. The chickens raised in automatic and semi-automatic systems and during warm seasons showed lower carcass yield and worse meat quality (great values of drip loss and acidity, small values of tenderness), and higher rates of carcass defects. Chickens raised in a non-automatic system and during cold seasons showed the best performance, with low mortality rate and the best meat quality.

The use of PCM panels to improve storage condition of frozen food

An investigation into the effect of phase change material (PCM) panels placed against the internal walls of a freezer during repeated power loss every 24 h over a 2 week period was conducted. Comparisons of the freezer air temperature and product temperature in a freezer containing PCM panels showed lower temperature fluctuations than in a freezer without PCM. Product analysis was also conducted by measuring the drip loss in 1 × 1 cm cubes of bovine muscle ( Musculus semimembranosus) and the ice crystal size in 1 L blocks of vanilla ice cream. Drip loss was measured by centrifuging the samples and weighing the drip collected. Analysis of ice crystal diameters was conducted by microscopy and an image analysis tool. Drip loss in meat was found to be lower and ice crystal sizes in the ice cream were found to be smaller in the freezer with PCM compared to without PCM.

Effects of transport stress on blood metabolism, glycolytic potential, and meat quality in meat-type yellow-feathered chickens

To investigate the effects of transport stress on blood metabolism, glycolytic potential, and meat quality in male Chinese Lingnan meat-type yellow-feathered chickens, three hundred sixty 72-d-old birds were randomly assigned to 1 of 5 treatments: unstressed control, 45-min (short-term) transport with 45-min (short-term) recovery, 45-min transport with 3-h (long-term) recovery, 3-h (long-term) transport with 45-min recovery, and 3-h transport with 3-h recovery. Each treatment consisted of 6 replicates with 12 birds each. All birds (except control group) were transported according to a designed protocol. Long-term transport decreased the plasma glucose level (P < 0.001), glycogen concentration in both breast (P = 0.023) and thigh (P = 0.012) muscles, and affected the size of IIb fibers in the tibialis anterior by decreasing the area (P = 0.031) and increasing the density (P = 0.046), drip loss (P = 0.045), and the a* (redness; P = 0.040) value in breast muscle. Long-term recovery after transport also decreased the plasma glucose level (P = 0.018) and showed a trend toward decreased breast glycogen concentration (P = 0.064). These results suggested that transport did not cause any noticeable changes in overall meat quality characteristics, although breast meat drip loss and meat color were affected. A long-term recovery from a period of feed and water deprivation also caused hypoglycemia and did not improve meat quality in Lingnan meat-type yellow-feathered chickens.

EFFECT OF SUPPLEMENTAL VE ON MEAT QUALITY AND ANTI-OXIDANT CAPACITY OF ADULT GRASS CARP

A Study was conducted to investigate the effects of supplemental vitamin E(VE) in practical diet on growth,meat quality and anti-oxidant capacity of adult grass carp(Ctenopharyngodon idellus).Basal diet,added with VE 0(control group),25,50,100 or 200 mg/kg,were fed to adult grass carp for 60 days.The basal diet contained 28.05% crude protein,3.25% crude fat and 24.1 mg/kg VE.Adult grass carp,with body weight of(614.9±60.5) g,were divided into five treatments with triplicate groups,and raised in 15 cement pools(3.0m×2.5m×1.2m).Fishes were fed twice per day(8:00 and 17:00) with the feed intake of 2% of the body weight.Growth rate,feed conversion rate(FCR),muscle composition,drip loss of fresh meat,exudative loss of freezing meat,VE and maleic dialdehyde(MDA) in liver and muscle,serum SOD,total antioxidant capacity(T-AOC) were measured.Results showed that growth rates of the five groups were 51.6%,53.5%,53.4%,53.5%,54.8%,and FCR were 2.28,2.17,2.20,2.19,and 2.15,respectively.There was no significantly effect of supplemental VE in diets on growth and FCR of adult grass carp,but growth rate tended to be increased and FCR tended to be decreased by supplemental 200mg/kg VE in diet(P0.10).With supplemental VE increased,the drip loss of fresh meat and exudative loss of freezing meat decreased,but the moisture,crude protein,crude fat of meat kept constant among all groups.The VE concentration of muscle and liver were significantly increased,whereas MDA was decreased by supplemental VE(P0.05).Compared with control group,VE of meat and liver were increased by 431.0%,353.7%,and MDA were decreased by 67.2%,61.3% by supplemental 200mg/kg VE in diet(P0.01).Compared with control group,when supplemental VE was higher than 50 mg/kg,serum SOD activities significantly increased(P0.05),and T-AOC was significantly higher when supplemental VE was 200mg/kg(P0.05).No significant difference in serum T-AOC was observed among groups of 0,50,100 mg/kg VE addition group.Results above showed that growth performance,meat quality and serum anti-oxidant capacity of adult grass carp could be improved by supplemental VE in diets.For adult grass carp,the VE supplement in practical diet(containing VE 24.1 mg/kg) was estimated to be 25 mg/kg according to the growth performance,or 200 mg/kg according to meat quality and anti-oxidant capacity.

Genetic parameters of meat quality traits in two pig breeds measured by rapid methods

To study genetic variation in meat quality traits measured by rapid methods, data were recorded between 2005 and 2008 on samples of M. longissimus dorsi (LD) in Landrace (n = 3838) and Duroc (n = 2250) pigs included in the Norwegian pig breeding scheme. In addition, ultimate pH levels in the glycolytic LD (loin muscle) and M. gluteus medius (GM, ham muscle), and in the oxidative m. gluteus profundus (GP, ham muscle) were recorded as an extended data set (n = 16 732 and n = 7456 for Landrace and Duroc, respectively) from 1998 to 2008. Data were analysed with a multi-trait animal model using AI-REML methodology. Meat from Duroc had considerably more intramuscular fat (IMF), less moisture and protein, appeared darker with higher colour intensity and had lower drip loss than meat from Landrace. The heritability estimates (s.e. 0.01 to 0.07) for pH in LD (0.19 and 0.27 for Landrace and Duroc, respectively), GM (0.12 and 0.22) and GP (0.19 and 0.38), drip loss (0.23 and 0.33), colour values: L* (lightness) (0.41 and 0.28), a* (redness) (0.46 and 0.43), b* (yellowness) (0.31 and 0.33), IMF (0.50 and 0.62), muscle moisture (0.31 and 0.50) and muscle protein content (0.40 and 0.54) in LD all demonstrated moderate-to-high genetic variation for these traits in both breeds. Near infrared spectroscopy and EZ-DripLoss are modern technologies used in this study for the determination of chemical components and drip loss in meat. These methods gave higher heritabilities than more traditional methods used to measure these traits. The estimated genetic correlations between moisture and IMF in Duroc, and pH and drip loss in Duroc were both −0.89. Interesting differences between the two breeds in numerical value of some genetic correlations were observed, probably reflecting the differences in physiology and selection history between Landrace and Duroc. The estimated genetic correlation between drip loss and pH was much stronger in Duroc than in Landrace (−0.89 and −0.63, respectively). This might be due to the high pH in Duroc, whereas Landrace had a lower pH closer to the iso-electric point for muscle proteins. The positive genetic correlation between the L* value in meat and IMF in Duroc (0.50) was an effect of differences in visible marbling, rather than meat colour. For Landrace, this correlation was negative (−0.20). IMF content showed favourable genetic correlations to drip loss (−0.36 and −0.35 for Landrace and Duroc, respectively).

Effect of dietary tea catechins supplementation in goats on the quality of meat kept under refrigeration

Liuyang black male goats were used to examine the effects of TC inclusion on lipid oxidation and fresh meat quality of goats. Forty goats were randomly divided into four equal groups (ten animals in each group) and assigned to four experiment diets with TC supplementation at four levels (0, 2000, 3000 and 4000 mg TC/kg feed). After 60 days of feeding period, all goats were slaughtered and sampled. The results showed that dietary TC supplementation had significant ( P < 0.05) effect on plasma total antioxidant status (TAS) at days 40 and 60, lipid oxidation of M. longissimus dorsi (LD), gluteus medius (GM) and semimemberanosus (SM), pH value of GM and SM at 24 h postmortem, intramuscular fat (IMF) of SM, drip loss percentage of GM and SM, and total haem pigment content (THP) of LD and SM. In conclusion, suitable dietary TC level could inhibit lipid oxidation, decrease drip loss of fresh meat and improve meat colour stability in goat, moreover, dietary TC inclusion influences muscle pH values and IMF at some degree, but different muscle types showed different trend to change, and the quality of LD was relatively stable according to overall evaluation.

Effects of Dietary Selenomethionine Supplementation on Growth Performance, Meat Quality and Antioxidant Property in Yellow Broilers

This study was conducted to investigate the effects of dietary selenomethionine (Se-Met) supplementation on growth performance, meat quality and antioxidant property in male broilers. A total of 800 43-day-old Lingnan yellow male broilers were randomly allotted to 5 dietary treatments with four replicates of 40 birds for a period of 3 weeks ad libitum. Final BW and weight gain of birds significantly increased by Se-Met supplementation at the 0.225 mg/kg level (P < 0.05). The addition of Se-Met significantly decreased drip loss, lightness value, and elevated pH value of meat (p < 0.05). Adding sodium selenite (SS) only increased pH value of meat (p < 0.05). In plasma, supplemental Se-Met at 0.225 mg/kg level increased total antioxidant capability (T-AOC), glutathione peroxidase (GPX), total superoxide dismutase (T-SOD), catalase (CAT) activities, glutathione (GSH) concentration (p < 0.05), and decreased malondialdehyde production (p < 0.05), compared with the control and broilers fed SS diet. In breast muscle, the addition of Se-Met significantly elevated T-AOC, GPX, T-SOD, CAT activities, contents of metallothionein and GSH (p < 0.05), and reduced carbonyl protein content (p < 0.05). While compared with broilers fed SS diet, supplemental 0.225 mg/kg Se-Met increased T-AOC, GPX, CAT activities, and GSH content (p < 0.05). Therefore, dietary Se-Met supplementation could improve growth performance and meat quality by enhancing antioxidative capacity in broilers compared with SS.

An attempt to predict pork drip loss from pH and colour measurements or near infrared spectra using artificial neural networks

The ability to predict meat drip loss by using either near infrared spectra ( SPECTRA) or different meat quality ( MQ) measurements, such as pH 24, Minolta L ∗, a ∗, b ∗, along with different chemometric approach, was investigated. Back propagation (BP) and counter propagation (CP) artificial neural networks (ANN) were used and compared to PLS (partial least squares) regression. Prediction models were created either by using MQ measurements or by using NIR spectral data as independent predictive variables. The analysis consisted of 312 samples of longissimus dorsi muscle. Data were split into training and test set using 2D Kohonen map. The error of drip loss prediction was similar for ANN (2.2–2.6%) and PLS models (2.2–2.5%) and it was higher for SPECTRA (2.5–2.6%) than for MQ (2.2–2.3%) based models. Nevertheless, the SPECTRA based models gave reasonable prediction errors and due to their simplicity of data acquisition represent an acceptable alternative to classical meat quality based models.

Effects of Ligustrum lucidum Fruits on Growth Performance, Antioxidation and Meat Quality in Arbor Acres Broilers

This study was conducted to evaluate the effects of Ligustrum lucidum (LL) on growth performance, antioxidation, and meat quality in broilers. 270 birds (1 d old) were allotted to 3 treatments with 6 replicates per treatment. The feeding program included a starter diet from d 1 to 21 of age and a grower diet from d 22 to 42 of age. The birds were given a basal corn-soybean meal diet supplemented with 0 (the control), 5 or 10 g of LL/kg, respectively. The results showed that in the starter, grower and overall phase, broilers fed with 5 or 10 g of LL/kg had better (p<0.01) average daily gain, but there were no differences in feed: gain between treatments. In the starter and overall phase, average daily feed intake of LL groups was greater (p<0.05) than that of the control, but this difference was not observed in the grower phase. Supplementation of LL significantly increased (p<0.05) superoxide dismutase activity and total antioxidant capability in serum of chickens. In breast muscle, birds fed 5 g of LL/kg had an increase (p<0.05) in superoxide dismutase activity. The LL supplementation significantly decreased (p<0.05) malondialdehyde contents. Adding 5 or 10 g of LL/kg to the diet significantly increased pH value and reduced drip loss of meat (p<0.05). The results of this study indicated that dietary LL could improve growth performance, increase pH value and reduce drip loss of meat by decreasing lipid peroxidation and by improving antioxidative status in broilers.

Near infrared spectroscopy in animal science production: principles and applications

Near infrared (NIR) is one of the techniques belonging to vibrational spectroscopy. Its radiation (750 to 2500nm) interacts with organic matter, and the absorption spectrum is rich in chemical and physical information of organic molecules. In order to extract valuable information on the chemical properties of samples, it is necessary to mathematically process spectral data by chemometric tools. The most important part in the development of an NIR method is building the predicting model generally called calibration. NIR spectroscopy has several advantages over other analytical techniques: rapidity of analysis, no use of chemicals, minimal or no samples preparation, easily applicable in different work environments (on/in/at line applications). On the other hand, NIR spectroscopy has some disadvantages: low ability to predict compounds at low concentration (<0.1%), necessity of accurate analysis as reference, development of calibration models required high trained personnel, need of a large and up-to-date calibration data set (often difficult to obtain), difficulties to transfer calibration among instruments, initial high financial investments. In the feed industry, NIR spectroscopy is used for: feed composition, digestibility (in vivo, in vitro, in situ), traceability assessment (to avoid possible frauds). As far as animal products are concerned, NIR spectroscopy has been used to determine the main composition of meat, milk, fish, cheese, eggs. Furthermore, it was also used to predict some physical properties (tenderness, WHC (Water Holding Capacity), drip loss, colour and pH in meat; coagulation ability in milk; freshness, flavour and other sensorial parameters in cheese). Interesting applications of NIR spectroscopy regard issues like: determination of animal products’ authenticity and the detection of adulteration (in order to prevent frauds), discrimination PDO (Protected Designation of Origin) and PGI (Protected Geographical Indication) from other non traditional products, detect handling aspects (freezing, thawing or fresh). There is a growing interest in the evaluation of animal products’ quality directly on-line to have a continuous control of the production process. Furthermore, new portable instruments are becoming now available, which will allow to easily monitor some processes at the factory (i.e. ripening and ageing of sausages and cheeses).

Chicken meat quality as a function of fasting period and water spray

This study aimed at evaluating the effect of different fasting periods and water spray during lairage on the quality of chicken meat. A number of 300 male Ross broilers were reared up to 42 days of age, and submitted to four pre-slaughter fasting periods (4, 8, 12, and 16 hours) and sprayed with water or not during lairage. Deboned breast meat was submitted to the following analysis: pH, color, drip loss, water retention capacity, cooking loss, and shear force. There was a significant effect (p < 0.05) of fasting period on meat luminosity was significantly different, with the highest value obtained for 4-hour fasting, whereas no difference was found among the other fasting periods. Meat pH values were different among fasting periods when birds received water spray, with birds fasted for 4, 8, and 12 hours of fasting presenting lower meat pH values (5.87, 5.87, and 6.04, respectively). The interaction between fasting period and water spray influenced meat drip loss and cooking loss, with birds fasted for 16h and not receiving water spray presenting higher drip loss (4.88) and higher cooking loss (28.24) as compared to the other birds. Fasting period affects meat quality, and very short periods (4h) impair meat quality.