Changes in gene expression in the intestinal mucus of broilers with woody breast myopathy.

Previous work has shown that dietary treatments affect woody breast (WB) incidence differently, which indicates that gut conditions such as gut barrier function, inflammation, and oxidative stress are likely related to WB. In this study, dietary supplementation with antibiotics (bacitracin) or probiotics (Bacillus subtilis) was investigated for their effects on the expression of transcripts related to gut barrier function, inflammation, and oxidative stress in the mucus lining of the jejunum from broilers with or without WB. A split-plot experimental design was used in this study. The dietary treatments served as the main plot factor and the breast muscle condition was the subplot factor. On d 41, jejunum mucus was collected from 1 bird from each of 3 replicate pens in each 3 dietary treatment groups that exhibited WB and an additional bird that contained a normal breast (3 biological replicates/treatment/phenotype; 3 × 3 × 2, total N = 18). Total RNA was extracted using a commercial RNA extraction kit. The expression levels of CLDN1, MUC6, TLR2A, TLR2B, TLR4, IFN-γ, IL-1ß, IL-8L1, IL-10, NOS2, and SOD were determined using 2-step RT-qPCR analysis. The gene expression difference in ΔCt values was determined after normalizing with the chicken 18S rRNA gene. When the significant differences occurred between treatments, the relative fold change was calculated using the ΔΔCt method and the significance level was calculated. The PROC GLM procedure of SAS 9.4 was used, and the level of significance was set at P ≤ 0.05. There were no significant interactive effects between diet and the breast muscle condition on the expression of any of the genes tested. However, birds with WB exhibited higher MUC6 (P < 0.0001) gene expression levels than birds with normal breast muscles. In addition, the expression of SOD decreased in birds that were fed the antibiotic diet when compared to birds that were fed the probiotic diet (P = 0.014). In conclusion, WB identified in broilers tested in the current study is attributed to increased expression of mucin, indicating a correlation between WB incidence and gel-forming mucin secretion and pathogen signaling.

Aerotolerance and Multi-Locus Sequence Typing of Campylobacter jejuni Isolated from Commercial Broiler Processing Plants.

Campylobacter jejuni is one of the leading causes of acute diarrhea in the United States. Despite being a microaerophilic pathogen, C. jejuni continues to endure within the domain of food production, especially in poultry processing. Recent research on aerotolerance indicates that close monitoring of this pathogen is necessary. A total of 40 C. jejuni isolates previously obtained from commercial broiler processing plants were analyzed for aerotolerance and genetic diversity. In addition, the effect of aerotolerance and storage time (days) on the survival of C. jejuni on broiler drumsticks at refrigeration (4 °C) and freezing conditions (-20 °C) was also evaluated. Out of 40 isolates, 25 (62.5%) were aero-sensitive (AS), 10 (25%) were intermediately aerotolerant (IAT), and 5 (12.5%) were hyper aerotolerant (HAT). The isolates belonged to four clonal complexes (CCs) and six sequence types, with the majority of isolates assigned to the CC-353 clonal complex. C. jejuni counts were reduced by 0.40 log CFU/g after 7 days at 4 °C and by 1.50 log CFU/g after 14 days at -20 °C, respectively, irrespective of aerotolerance (p < 0.001). At both refrigeration (p < 0.013) and freezing (p < 0.001), HAT showed greater reductions as compared to AS and IAT. These findings suggest that both refrigeration and freezing reduce C. jejuni counts.

Inosine 5'- monophosphate derived umami taste intensity of beef determination by electrochemistry and chromatography.

The umami sensation contributes to beef taste and acceptability. Inosine 5'- monophosphate (IMP), the most abundant 5'-ribonucleotide in meat, is known to impart an umami taste without the undesired side effects commonly associated with glutamate. Nevertheless, the investigation of IMP's role in beef flavor has thus far been overlooked. Traditional methods for detecting IMP have relied on liquid chromatography coupled with ultraviolet spectroscopy or mass spectrometry techniques. However, these methods are not practical for production settings due to the complexity and resource demands of sophisticated laboratory techniques. Alternative methods like cyclic voltammetry might offer more practical solutions for rapidly detecting IMP. The objectives of this study were to evaluate the efficiency of using electrochemistry and chromatography on differentiating beef strips spiked with different IMP contents. The IMP threshold was 0.30 mM determined by a trained panel using the Best Estimates Threshold method. Beef strip steaks of USDA Prime, Choice, and Select were spiked at 0.30 and 0.60 mM of IMP, based on green weight and an estimated moisture content of 65%. In this study, differences in the IMP content of steaks were not detected by liquid chromatography-mass spectrometry. However, the cyclic voltammetry approach differentiated IMP concentrations at 0.50 mM or above in aqueous solutions and subsequentially meat extracts from the buffered blank solutions. In conclusion, cyclic voltammetry holds potential as a rapid and effective approach for detecting IMP in beef and other meat products, offering promising applications for future research.

Efficacy of the Fumigants Propylene Oxide and Ethyl Formate to Control Two Pest Species of Dry-Cured Hams.

The ham mite Tyrophagus putrescentiae and the red-legged ham beetle Necrobia rufipes are harmful pests to several high-valued stored products. The regulatory phase-out of the fumigant methyl bromide necessitates the search for alternative fumigants. Propylene oxide (PPO) and ethyl formate (EF) were therefore evaluated in the laboratory for controlling these pests of dry-cured hams. Concentration-mortality studies at 25 °C of PPO and EF found that the mobile stages of the mites were very susceptible to low concentrations of 10 mg/L and less of each gas, while mite eggs were very tolerant and required 20 mg/L for PPO and 80 mg/L of EF for 100% mortality. Mixed life stage cultures of mites and beetles were treated for 24 h with either PPO or EF at 1× and 2× the estimated 99% lethal doses and confirmed effectiveness for controlling simulated pest populations. The sorptive properties of each gas in chambers with ham pieces, dog food kibbles, or fish meal were minimal for a reduction in mite toxicity when compared to treatments in empty chambers. There was no evidence that any desorbed gas occurred at a level toxic to mite eggs in any of the fumigated commodities. These fumigation studies with ham pests support further work with PPO and EF on any changes in the sensory quality of dry-cured hams for human taste and for commercial-scale fumigations toward regulatory approval.

Using liquid smoke to control infestations of the ham mite, Tyrophagus putrescentiae, on dry-cured hams during aging.

Eight treatments of edible coatings and nets including liquid smoke (SP and 24P) and xanthan gum (XG) were used to evaluate their effectiveness at controlling mite growth on dry-cured hams. Mite growth was controlled (P < 0.05) in both coating and netting treatments of 1% SP + 1% XG. Increasing SP concentration from 1% to 2% in the SP only treatments without XG did not control mite growth (P > 0.05) in the coating but controlled mite growth (P < 0.05) when infused in the nets. Both coating and netting treatments with 2% 24P + 1% XG controlled mite growth (P < 0.05), and ham cubes with 1% and 2% 24P in infused nets had mite numbers of 4.6 and 9.4, respectively. SP did not impact the sensory attributes of the ham. Results indicate that liquid smoke can potentially be added in coatings or ham nets to control mites and used in an integrated pest management program for dry-cured hams.

Study of emerging chicken meat quality defects using OMICs: What do we know?

Starting in approximately 2010, broiler breast meat myopathies, specifically woody breast meat, white striping, spaghetti meat, and gaping have increased in prevalence in the broiler meat industry. Omic methods have been used to elucidate compositional, genetic, and biochemical differences between myopathic and normal breast meat and have provided information on the factors that contribute to these myopathies. This review paper focuses on the genomic, transcriptomic, proteomic, metabolomic, and other omics research that has been conducted to unravel the molecular mechanisms involved in the development of these myopathies and their associated factors and potential causes. SIGNIFICANCE: This review manuscript summarizes poultry meat quality defects, also referred to as myopathies, that have been evaluated using omics methods. Genomics, transcriptomics, proteomics, metabolomics and other methodologies have been used to understand the genetic predisposition, the protein expression, and the biochemical pathways that are associated with the expression of woody breast meat, white striping, and other myopathies. This has allowed researchers and the industry to differentiate between chicken breast meat with and without myopathic muscle as well as the environmental and genetic conditions that contribute to differences in biochemical pathways and lead to the phenotypes associate with these different myopathies.

Internal organ and skeletal muscle development in commercial broilers with woody breast myopathy.

Increasing growth rate, body weight, and breast muscle yield have been linked to broiler muscle problems such as woody breast (WB). The aim of this study was to investigate the internal organ and skeletal muscle development of broilers with WB myopathy under dietary and Eimeria challenge treatments. A 3 diet (control, antibiotic, or probiotic) × 2 challenge (control or Eimeria) × 2 sex factorial arrangement of treatments was used in a randomized complete block design. Ross × Ross 708 chicks were randomly assigned to 96 floor pens with 12 treatment combinations (8 replicates per treatment). Internal organs were sampled on d 13 and 41. Skeletal muscles were sampled on d 41. Internal organ and skeletal muscle weights were analyzed using a 3-way analysis of variance (ANOVA). Relationships between WB and internal organ and skeletal muscle weights were analyzed using one-way ANOVA as all treatments were pooled together and regrouped according to WB scores. On d 41, absolute and relative heart weights were greater in males when they were averaged over diet and challenge treatments (P < 0.001 and P = 0.026, respectively). The birds with WB score 3 had greater absolute heart (P = 0.0002) and spleen weights (P = 0.016), but there was no difference in relative spleen weight (P > 0.05). When averaged over diet and challenge treatments, males have greater absolute duodenum, jejunum, and ileum weights (for all P < 0.0001). Compared with birds with normal breasts, the birds with WB scores 1, 2, and 3 had a greater live weight (for all P < 0.0001) and absolute and relative breast weights (for all P < 0.0001). The birds with WB score 1, 2, and 3 had greater (P < 0.0001) absolute but lower (P < 0.0001) relative drumstick, thigh, and wing weights. Results indicated that broilers with WB had lower relative proventriculus and gizzard weights and greater relative breast meat weight with lower relative drumstick, thigh, and wing muscle weights.

Effects of dietary bacitracin or Bacillus subtilis on the woody breast myopathy-associated gut microbiome of Eimeria spp. challenged and unchallenged broilers.

Study suggested that dysbiosis of the gut microbiota may affect the etiology of woody breast (WB). In the current study, the cecal microbiota and WB in chickens fed three different diets were investigated. A total of 504 male chicks were used in a randomized complete block design with a 3 (Diet) × 2 (Challenge) factorial arrangement of treatments with 6 replicates per treatment, 6 treatments per block, and 14 birds per treatment. The experimental diets were a control diet (corn-soybean meal basal diet), an antibiotic diet (basal diet + 6.075 mg bacitracin/kg feed), and a probiotic diet (basal diet + 2.2 × 108 CFU Bacillus subtilis PB6/kg feed). On d 14, birds that were assigned to the challenge treatment received a 20 × live cocci vaccine. On d 41, breast muscle hardness in live birds was palpated and grouped into normal (NB) and WB phenotypes. Cecal contents were collected and their bacterial compositions were analyzed and compared. The genomic DNA of the cecal contents was extracted and the V3 and V4 regions of 16S rRNA gene were amplified and sequenced via an Illumina MiSeq platform. There were no differences (P > 0.05) in Shannon and Chao 1 indexes between the challenges, diets, and phenotypes (NB vs. WB). However, there was a difference (P = 0.001) in the beta diversity of the samples between the challenged and nonchallenged groups. Relative bacterial abundance differed (false discovery rate, FDR < 0.05) between the challenge treatments, but there were no significant differences (FDR > 0.05) among the three diets or two phenotypes. Predicted energy metabolism, nucleotide metabolism, and amino acid and coenzyme biosynthesis activities only differed (q-value < 0.05) between challenged and nonchallenged groups. The cocci challenge altered the gut microbial composition on Butyricicoccus pullicaecorum, Sporobacter termitidis, and Subdoligranulum variabile, but the dietary antibiotic and probiotic treatments did not impact gut microbial composition. No strong association was found between WB myopathy and gut microbial composition in this study.

Genetic Variation in Taste Receptor Genes (SCNN1B, TRPV1) and Its Correlation with the Perception of Saltiness in Normotensive and Hypertensive Adults.

BACKGROUND: Different taste preferences correlated with genetic variations may lead to food consumption patterns that contribute to nutrient-related health outcomes such as hypertension. OBJECTIVES: The aim of this study was to determine whether single nucleotide polymorphisms (SNPs) in the salt taste receptor genes SCNN1B and TRPV1 affect salt taste perception among normotensive and hypertensive people. MATERIALS AND METHODS: We conducted a cross-sectional case control study by design consisting of a normotensive and hypertensive group. Participants were 253 adults with age range of 20-82 residing in Mississippi, USA. For each of 128 normotensives and 125 hypertensives, the salt taste recognition threshold and salt taste receptor genotype were determined. RESULTS: The hypertensive group had a higher salt taste recognition threshold than the normotensive group (P < 0.001). The polymorphism of TRPV1, rs4790522, with the AA genotype was associated with a higher salt recognition threshold (lower salt taste sensitivity) in people with hypertension and obesity. Moreover, the polymorphism of TRPV1, rs8065080, and SCNN1B, rs239345, genes were associated with a risk of hypertension (P=0.016 and P=0.024). CONCLUSION: Correlations between SNPs, salt taste sensitivity, and hypertension risk were observed. People with hypertension had a higher salt taste threshold than those with normotension.

Cecal microbiota contribute to the development of woody breast myopathy.

The objective of this study was to characterize the bacterial diversity of cecal microbiota in broilers related to breast phenotype, diet, and genetic strain. Broilers from 2 genetic strains (120 birds/strain) were fed a control diet (15 birds/pen) and an amino acid reduced diet (15 birds/pen, digestible lysine, total sulfur amino acids, and threonine reduced by 20% compared to the control diet). At 8 wk of age, 4 male broilers with normal breast (NB, 1 chick per pen) and 4 male broilers with woody breast (WB, 1 chick per pen) were selected for each treatment (strain × diet). The DNA of cecal samples was extracted and the 16S rRNA genes were sequenced and analyzed. There were no differences (P > 0.05) in the alpha diversity of gut microbiota between 2 phenotypes (NB vs. WB), 2 strains, or 2 diets (control vs. reduced). However, principal coordinate analysis plots (beta diversity) revealed that there were composition differences in samples between the 2 phenotypes (P = 0.001) and the 2 diets (P = 0.024). The most abundant phyla in all samples were Firmicutes, followed by Bacteroidetes and Proteobacteria. There were differences (false discovery rate, FDR < 0.05) in bacterial relative abundance between phenotypes and between diet treatments, but not (FDR > 0.05) between the 2 genetic strains. Selenomonas bovis (12.6%) and Bacteroides plebeius (12.3%) were the top 2 predominant bacteria in the ceca of WB birds; however, the relative abundances of these 2 bacteria were only 5.1% and 1.2% in NB birds, respectively. Function analysis predicted that the metabolic activities differed (q < 0.05) only between phenotypes. The microbiota of WB birds was characterized as reduced glycolysis and urea cycle but increased tricarboxylic acid (TCA) cycles, sugar degradation, and purine and pyrimidine nucleotides biosynthesis. Further studies are needed to investigate if WB incidence could be reduced by regulating gut microbiota and the potential mechanism that leads to decreased WB incidence.

Effects of broiler genetic strain and dietary amino acid reduction on meat yield and quality (part II).

Genetic selection and advances in nutrition have improved broiler growth performance. However, meat quality issues have gained preference over increased growth rate. These meat quality issues may be reduced by lowering dietary amino acid (AA) content. In the present study, 5 common commercial broiler strains were fed either a control or an AA-reduced diet. The control diet was formulated to contain the highest digestible AA (lysine, total sulfur AA, and threonine) levels recommended for the 5 strains. The AA-reduced diet was formulated to contain 20% lower levels of these 3 digestible AA than in the control diet. This resulted in a 5 (strains) × 2 (AA levels) factorial arrangement. A total of 1,280 straight run broilers were randomly allocated to 8 replicate blocks. The AA reduction decreased absolute breast weights of 3 strains on day 42 and 2 strains on day 56, and decreased absolute weights of tender, wing, drumstick, and thigh on both day 42 and 56 for all 5 strains. However, the absolute fat pad weight and relative fat pad and thigh weights to BW were increased in the AA reduction treatments on both day 42 and 56. The AA reduction contributed to the lower breast meat pH on both day 42 and 56, which may have been directly related to decreased severe woody breast myopathy (WBM) incidence on day 42 and moderate WBM incidence on day 56. The severity of WBM was positively related to breast weight in all 10 treatments on both day 42 and 56, with the exception of birds in strain 3 on day 56 that were fed the AA-reduced diet. At the same time, AA reduction was more cost-effective when WBM incidence was considered in a theoretical model. In conclusion, WBM severity was associated with higher breast weight in birds of most strains fed either a control or AA-reduced diet. Dietary AA reduction decreased processing yields but decreased WBM incidence, which may be more economical.

Broiler genetics influences proteome profiles of normal and woody breast muscle.

Wooden or woody breast (WB) is a myopathy of the pectoralis major in fast-growing broilers that influences the quality of breast meat and causes an economic loss in the poultry industry. The objective of this study was to evaluate growth and proteome differences between 5 genetic strains of broilers that yield WB and normal breast (NB) meat. Eight-week-old broilers were evaluated for the WB myopathy and divided into NB and WB groups. Differential expression of proteins was analyzed using 2-dimensional gel electrophoresis and LC-MS/MS to elucidate the mechanism behind the breast myopathy because of the genetic backgrounds of the birds. The percentages of birds with WB were 61.3, 68.8, 46.9, 45.2, and 87.5% for strains 1-5, respectively, indicating variability in WB myopathy among broiler strains. Birds from strains 1, 3, and 5 in the WB group were heavier than those in the NB group (P < 0.05). Woody breast meat from all strains were heavier than NB meat (P < 0.05). Within WB, strain 5 had a greater breast yield than strains 1, 3, and 4 (P < 0.0001). Woody breast from strains 2, 3, 4, and 5 had a greater breast yield than NB (P < 0.05). Six proteins were more abundant in NB of strain 5 than those of strains 2, 3, and 4, and these proteins were related to muscle growth, regeneration, contraction, apoptosis, and oxidative stress. Within WB, 14 proteins were differentially expressed between strain 5 and other strains, suggesting high protein synthesis, weak structural integrity, intense contraction, and oxidative stress in strain 5 birds. The differences between WB from strain 3 and strains 1, 2, and 4 were mainly glycolytic. In conclusion, protein profiles of broiler breast differed because of both broiler genetics and the presence of WB myopathy.

Metabolite profile and consumer sensory acceptability of meat from lean Nellore and Angus × Nellore crossbreed cattle fed soybean oil.

Thirty each Nellore (NEL) and crossbred Angus × Nellore (AxN) were used to evaluate the effect of feeding soybean oil (SBO) and breed on meat sensory acceptability and its relation to muscle metabolite profiles. Cattle were fed for 133 d on two different diets: 1) basal feedlot diet (CON) and 2) CON diet with 3.5% added SBO. No interactions between diet and genetic group were detected for any traits measured. Meat from animals fed SBO diet had lower overall liking, flavor, tenderness and juiciness scores compared to meat from animals fed CON diet. The four most important compounds differing between animals fed CON and SBO diets were betaine, glycerol, fumarate, and carnosine, suggesting that metabolic pathways such as glycerolipid metabolism; glycine, serine and threonine metabolism; glutamine and glutamate metabolism; valine, leucine and isoleucine biosynthesis; and alanine, aspartate and glutamate metabolism were affected by diets. Nellore beef had a higher overall liking and meat flavor scores than AxN beef. The four most important compounds differing between breeds were glycine, glucose, alanine, and carnosine, which may indicate that metabolic pathways such as glutathione metabolism; primary bile acid biosynthesis; alanine, aspartate and glutamate metabolism; and valine, leucine and isoleucine biosynthesis were affected by genetic groups. Meat carnosine, inosine monophosphate, glutamate, betaine, glycerol and creatinine levels were correlated with sensory acceptability scores. Meat metabolite profiles and sensory acceptability were differentially impacted by diet and breed.

Application of natural antioxidant extract from guava leaves (Psidium guajava L.) in fresh pork sausage.

The current study was conducted to determine the antioxidant efficacy of guava leaf extract (3000 to 6000 ppm on fat basis) in fresh pork sausage, compared with negative control (CON) and 200 ppm butylated hydroxytoluene (BHT), for 0, 1, 4, 7, 10, and 14 d at 4 °C. The extract provided a total antioxidant capacity of 1505 µmol trolox equivalence/g. From d 4, the extract at 5000 and 6000 ppm provided greater (P < .05) antioxidant capacity than the CON and was either similar (P > .05) or greater (P < .05) than BHT. From d 4, the sausage formulated with 4000 to 6000 ppm of guava leaf extract had less conjugated dienes, lower peroxide and acidic values, less thiobarbituric reactive substances value, and better color (P < .05) than the CON and did not differ from BHT (P > .05). Guava leaf extract at 4000 ppm or greater is effective in preventing oxidation in fresh pork sausage.

Differential abundance of muscle proteome in cultured channel catfish (Ictalurus punctatus) subjected to ante-mortem stressors and its impact on fillet quality.

The effects of environmental and handling stress during catfish (Ictalurus punctatus) aquaculture were evaluated to identify the biochemical alterations they induce in the muscle proteome and their impacts on fillet quality. Temperature (25°C and 33°C) and oxygen (~2.5mg/L [L] and >5mg/L [H]) were manipulated followed by sequential socking (S) and transport (T) stress to evaluate changes in quality when fish were subjected to handling (25-H-ST; temperature-oxygen-handling), oxygen stress (25-L-ST), temperature stress (33-H-ST) and severe stress (33-L-ST). Instrumental color and texture of fillets were evaluated, and muscle proteome profile was analyzed. Fillet redness, yellowness and chroma decreased, and hue angle increased in all treatments except temperature stress (33-H-ST). Alterations in texture compared to controls were observed when oxygen levels were held high. In general, changes in the abundance of structural proteins and those involved in protein regulation and energy metabolism were identified. Rearing under hypoxic conditions demonstrated a shift in metabolism to ketogenic pathways and a suppression of the stress-induced changes as the severity of the stress increased. Increased proteolytic activity observed through the down-regulation of various structural proteins could be responsible for the alterations in color and texture.

Transparent bionanocomposite films based on chitosan and TEMPO-oxidized cellulose nanofibers with enhanced mechanical and barrier properties.

The development of biobased active films for use in food packaging is increasing due to low cost, environmental appeal, renewability and availability. The objective of this research was to develop an effective and complete green approach for the production of bionanocomposite films with enhanced mechanical and barrier properties. This was accomplished by incorporating TEMPO-oxidized cellulose nanofibers (2,2,6,6-tetramethylpiperidine-1-oxyl radical) into a chitosan matrix. An aqueous suspension of chitosan (100-75wt%), sorbitol (25wt%) and TEMPO-oxidized cellulose nanofibers (TEMPO-CNFs, 0-25wt%) were cast in an oven at 40°C for 2-4days. Films were preconditioned at 25°C and 50% RH for characterization. The surface morphology of the films was revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thermal properties and crystal structure of the films were evaluated by thermogravimetric analysis (TGA-DTG) and X-ray diffraction (XRD). Incorporation of TEMPO-CNFs enhanced the mechanical strength of the films due to the high aspect ratio (3-20nm width, and 10-100nm length) of TEMPO-CNFs and strong interactions with the chitosan matrix. Oxygen and water vapor transmission rates for films that are prepared with chitosan and TEMPO-CNFs (15-25wt%) were significantly reduced. Furthermore, these bionanocomposite films had good thermal stability. Use of TEMPO-CNFs in this method makes it possible to produce bionanocomposite films that are flexible, transparent, and thus have potential in food packaging applications.

Proteome basis of pale, soft, and exudative-like (PSE-like) broiler breast (Pectoralis major) meat.

Pale, Soft, and Exudative (PSE) broiler breast meat has poor protein functionality, which leads to quality problems and economic loss in the poultry industry. Proteomics has been applied to characterize the biochemical mechanisms governing tenderness, color, and water-holding capacity in meat. However, the proteome basis of PSE has not yet been characterized for broiler breast meat. Therefore, this study was conducted to determine the differences in meat quality (cooking loss and shear force), descriptive sensory characteristics, consumer acceptance, and whole muscle proteome between normal and PSE-like broiler breast meat. Male Hubbard × Cobb 500 birds (n = 1,050) were raised in commercial houses. Prior to harvest, a sample of the broilers (n = 900) were subjected to short-term stress (38°C for 2 h), and the remaining broilers (n = 150) were maintained at control conditions (21°C for 2 h). Broiler breast (Pectoralis major) meat was collected and characterized by pH24 and L*24 as normal (pH24 5.8 to 6.2, L*24 45 to 55) or PSE-like (pH24 5.4 to 5.7, L*24 55 to 65) samples. Normal broiler breast meat had lower shear force values than PSE-like meat (P < 0.05). Based on sensory descriptive analysis, normal cooked chicken breast meat was more tender and juicier than PSE-like breast meat (P < 0.05). Consumer sensory analysis results indicated that 81% of consumer panelists liked normal breast meat whereas 62% of the panelists liked PSE-like breast meat. Whole muscle proteome profiling identified fifteen differentially abundant proteins in normal and PSE-like broiler breast samples. Actin alpha, myosin heavy chain, phosphoglycerate kinase, creatine kinase M type, beta-enolase, carbonic anhydrase 2, proteasome subunit alpha, pyruvate kinase, and malate dehydrogenase were over-abundant (P < 0.05) in PSE-like broiler breast whereas phosphoglycerate mutase-1, alpha-enolase, ATP-dependent 6-phosphofructokinase, and fructose 1,6-bisphosphatase were over-abundant (P < 0.05) in normal meat. Thus, results indicated that differences in proteome abundance could be related to the meat quality differences between normal and PSE-like broiler breast meat.

The Effects of Sequential Environmental and Harvest Stressors on the Sensory Characteristics of Cultured Channel Catfish (Ictalurus Punctatus) Fillets.

Stress during fish culture alters physiological homeostasis and affects fillet quality. Maintenance of high-quality seafood is important to ensure the production of a marketable product. This study assessed how sequential stressors affect the sensory and quality characteristics of catfish (Ictalurus punctatus) fillets. Three stress trials were conducted where temperature (25 or 33 °C) and dissolved oxygen (DO, approximately 2.5 or >5 mg/L) were manipulated followed by socking and transport stress. After each stage of harvest (environmental stress, socking, and transport), fillet yield, consumer acceptability, descriptive evaluation, cook loss, tenderness, and pH were evaluated. Fillet yield decreased with increasing severity of environmental stress. Fillets from the severe stress treatment (33 °C, approximately 2.5 mg/L) received the highest acceptability scores (P < 0.05). Control fillets (25 °C, >5 mg/L) were the least acceptable (P < 0.05). Increased intensity of less favorable flavor attributes commonly associated with catfish resulted in the differences in acceptability among treatments. As fish progressed through the harvest event, cook loss decreased, tenderness increased, and pH increased, indicating that stress induced textural changes. The data suggest that although environmental stress results in slight changes in flavor attributes, its effects on acceptability are minor with fillets from all treatments still liked (>6 on a 9 point scale). Socking and transport were identified to positively affect textural characteristics of catfish fillets. Although the effects observed were not likely to negatively impact consumer acceptance, a strict management plan should be followed to maintain consistency in the product and avoid changes in stressors that might alter quality more drastically.

Efficacy of selected food-safe compounds to prevent infestation of the ham mite, Tyrophagus putrescentiae (Schrank) (Acarina: Acaridae), on southern dry-cured hams.

BACKGROUND: Tyrophagus putrescentiae (Schrank) is a serious mite pest of dried meats and cheeses. Infestations of T. putrescentiae are controlled with the fumigant methyl bromide, which is an ozone-depleting substance and is currently being banned in most countries. Effective alternatives to methyl bromide are needed. The objective of this research was to use laboratory assays to investigate the effectiveness of food-safe compounds for preventing infestation of T. putrescentiae on dry-cured hams. RESULTS: Ham pieces dipped in solutions of either propylene glycol (1,2-propanediol), lard, ethoxyquin or butylated hydroxytoluene prevented or significantly reduced mite population growth. Behavioral assays revealed that more mites oriented to the untreated control ham cubes, and more eggs were laid on these untreated ham cubes, compared with cubes treated with various dips. Our results also indicated that a combination of carrageenan + propylene glycol alginate + 40% propylene glycol was effective in reducing mite numbers on whole aging hams compared with untreated whole hams. CONCLUSIONS: Several food-safe compounds can prevent infestation of T. putrescentiae on dry-cured hams and may represent alternatives for managing this pest. © 2015 Society of Chemical Industry.

Race and gender disparities in nutrient intake are not related to metabolic syndrome in 20- to 59-year-old US adults.

BACKGROUND: The goal of this study was to examine the relationship between macronutrient and micronutrient intake and metabolic syndrome within race and gender cohorts of young US adults. METHODS: The 2007-2010 National Health and Nutrition Examination Survey (NHANES) data for adults (n=2440) aged 20-59 were analyzed. Two 24-hr dietary recalls were used to measure intake of total calories, macronutrients, and 20 vitamins and minerals. Metabolic syndrome and its components were defined by the National Heart, Lung and Blood Institute criteria. Differences in statistical tests were noted when significant at P<0.05. RESULTS: Prevalence of metabolic syndrome among 20- to 59-year-old adults was 30.4% [95% confidence interval 27.6-33.2]. Among cohorts, metabolic syndrome was highest in black women and white men, and lowest in black men and white women. Regression analysis indicated that no macronutrients were associated with greater risk of metabolic syndrome. For relative macronutrient intake, men with metabolic syndrome consumed more polyunsaturated fats, whereas women with metabolic syndrome consumed more total, saturated and monounsaturated fats and less fiber and starch than women without metabolic syndrome. Among races, white men and women consumed greater absolute quantities of all macronutrients except carbohydrates and sugar. Micronutrient intake was greatest for white men and women; women without metabolic syndrome had greater micronutrient adequacy than women with metabolic syndrome. CONCLUSION: Nutrient intake varied between race/gender cohorts; however, there were few clinically significant differences in nutrient intake between those with and without metabolic syndrome. Diet may be marginally related to diagnosis of metabolic syndrome.