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1.
Poult Sci ; 97(3): 882-889, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29272435

RESUMO

Strategies that would increase eggshell quality could be of considerable value to egg producers. This research demonstrated the effective use of fibroblast growth factor 23 (FGF-23) peptide vaccines to increase eggshell quality of Single Comb White Leghorn laying hens (from 69 to 72 wk of age). Hens, fed a standard diet (containing 900 IU/kg vitamin D3), were intramuscularly injected (and boosted) with either a control vaccine (n = 14 hens) or one of 2 FGF-23 peptide vaccines (peptides NP1, GMNPPPYS; and NP7, YTSTERNSFH; n = 15 hens for each peptide). During peak antibody titer, eggs were collected for shell and internal quality analysis, hens were artificially inseminated, and the hatchability of fertilized eggs was determined. Laying hens vaccinated with either FGF-23 peptide NP1 or NP7 had increased (P < 0.05) plasma phosphate level (mmol/L; NP1 = 1.74, NP7 = 1.76, control = 1.47), egg specific gravity (NP1 = 1.083, NP7 = 1.083, control = 1.079), and eggshell strength (g of force; NP1 = 4002, NP7 = 4157, control = 3102) when compared to control vaccinated hens. FGF-23 peptide NP1 vaccinated hens also had increased eggshell thickness (mm, P < 0.001), shell weight (g, P = 0.032), and shell index (% of whole egg, P = 0.023) when compared to control vaccinated hens. FGF-23 peptide NP7 vaccinated hens tended to have decreased eggshell weight (P = 0.064) when compared to control vaccinated hens. Hatchability of fertilized eggs was not affected in incubations 1 and 3, but tended to be decreased (P = 0.097) by FGF-23 peptide NP1 vaccination in incubation 2. In conclusion, vaccines to FGF-23 peptides increased eggshell quality of laying hens with minimal adverse effects on egg internal quality. The effect of FGF-23 peptide vaccination on hatchability remains to be clarified.


Assuntos
Autoanticorpos/metabolismo , Proteínas Aviárias/metabolismo , Galinhas/fisiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Vacinas/imunologia , Animais , Casca de Ovo , Feminino , Fator de Crescimento de Fibroblastos 23 , Homeostase
2.
J Food Sci ; 81(2): C359-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26753985

RESUMO

The effect of levels (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) of added encapsulated (e) phosphate (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation inhibition during storage (0, 1, and 7 d) of ground meat (chicken, beef) was evaluated. The use of eSTP and eSPP resulted in lower and higher cooking loss (CL) compared to eHMP, respectively (P < 0.05). Increasing encapsulated phosphate level (PL) enhanced the impact of phosphates on CL in both chicken and beef samples (P < 0.05). Encapsulated STP increased pH, whereas eSPP decreased pH (P < 0.05). pH was not affected by PL. The highest orthophosphate (OP) was obtained with eSTP, followed by eSPP and eHMP (P < 0.05). The level of OP determined in both chicken and beef samples increased (P < 0.05) during storage. Increasing PL caused an increase in OP (P < 0.05). The highest reduction rate in the formation of thiobarbituric acid reactive substances (TBARS) and LPO for both meat species were obtained with eSPP, followed by eSTP and eHMP (P < 0.05). Increasing PL resulted in lower TBARS and LPO (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for the meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by increasing PL.


Assuntos
Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Peroxidação de Lipídeos , Carne/análise , Fosfatos , Animais , Cápsulas , Bovinos , Galinhas , Culinária , Difosfatos , Armazenamento de Alimentos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos , Oxirredução , Polifosfatos , Substâncias Reativas com Ácido Tiobarbitúrico/análise
3.
J Food Sci ; 80(10): C2161-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26317488

RESUMO

Effects of 0.5% encapsulated (e) phosphates (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation during storage (0, 1, and 7 d) of ground meat (chicken, beef) after being cooked to 3 end-point cooking temperatures (EPCT; 71, 74, and 77 °C) were evaluated. The use of STP or eSTP resulted in lower (P < 0.05) cooking loss (CL) compared to encapsulated or unencapsulated forms of HMP and SPP. Increasing EPCT led to a significant increase in CL (P < 0.05). Both STP and eSTP increased pH, whereas SPP and eSPP decreased pH (P < 0.05). The higher orthophosphate (OP) was obtained with STP or SPP compared to their encapsulated counterparts (P < 0.05). The lowest OP was determined in samples with HMP or eHMP (P < 0.05). A 77 °C EPCT resulted in lower OP in chicken compared to 74 and 71 °C (P < 0.05), dissimilar to beef, where EPCT did not affect OP. In encapsulated or unencapsulated form, using STP and SPP enhanced reduction in TBARS and lipid hydroperoxides (LPO) compared with HMP (P < 0.05). Regardless of the phosphate type, more effective lipid oxidation inhibition was achieved by the use of encapsulated forms (P < 0.05). Increasing EPCT resulted in lower TBARS in beef and higher LPO values in both beef and chicken samples (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by lowering EPCT.


Assuntos
Culinária , Manipulação de Alimentos/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/metabolismo , Carne/análise , Fosfatos/farmacologia , Temperatura , Animais , Cápsulas , Bovinos , Galinhas , Difosfatos/farmacologia , Conservação de Alimentos , Conservantes de Alimentos/farmacologia , Temperatura Alta , Metabolismo dos Lipídeos/efeitos dos fármacos , Oxirredução , Polifosfatos/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise
4.
Meat Sci ; 97(1): 93-103, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24553491

RESUMO

Effects of encapsulated sodium tripolyphosphate (STP), sodium hexametaphosphate (HMP) and sodium pyrophosphate (SPP) on lipid oxidation in uncooked (0, 2, 24h) and cooked (0, 1, 7 d) ground chicken and beef during storage were determined. Ten phosphate treatments included a control (no phosphate), three unencapsulated (u) at 0.5% and three encapsulated (e) phosphates (0.5%) each at a low (e-low) and high (e-high) coating level. Two heating rates (slow, fast) were investigated. Cooking loss (CL), pH, color, orthophosphate (OP), TBARS and lipid hydroperoxides (LPO) were determined. A fast heating and uSTP resulted in lower CL (p<0.05). Orthophosphate increased with phosphate incorporation, slow heating and storage (p<0.05). Encapsulated phosphates and increased coating level reduced OP (p<0.05). Unencapsulated STP increased CIE a* and pH, whereas uSPP decreased CIE a* and pH (p<0.05). Encapsulated phosphates and the greater coating level had no effect on the pH in cooked samples. Not increased coating level but encapsulated phosphates decreased lipid oxidation in cooked samples (p<0.05).


Assuntos
Culinária/métodos , Difosfatos/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Fosfatos/química , Polifosfatos/química , Animais , Bovinos , Galinhas , Cor , Concentração de Íons de Hidrogênio , Carne/análise , Oxirredução/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/análise
5.
J Anim Sci ; 89(2): 538-48, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20935137

RESUMO

During marketing, cattle may be exposed to periods of water deprivation. The impact of water and feed access and health status on the physiological well-being and carcass characteristics of Holstein slaughter cows during preslaughter marketing was studied through analysis of serum components, BW loss percentage, and fresh meat composition. Ninety-one multiparous Holstein cows (609 ± 89 kg mean BW, 2.9 ± 0.5 mean BCS, varying stage of lactation) were purchased over 3 wk in 3 groups (n = 31, 29, and 31) at a terminal market in central Wisconsin. Each cow was screened to determine health status (sick or not sick) and randomly assigned to 1 of 3 water and feed withdrawal treatment pens (AL, ad libitum access to water for 36 h; 18H, 18 h of ad libitum access to water followed by 18 h of water withdrawal; 36H, 36 h of water withdrawal; all 3 treatments included 36 h of feed withdrawal) in a randomized complete block arrangement with repeated measures for serum components. Blood samples were collected by tail venipuncture at 0, 9, 18, 27, and 36 h of each treatment. Ambient temperatures were 1.9 ± 6.2°C during the trial period, which occurred over a 3-wk period in March and April 2007 near Arlington, WI. No difference (P > 0.05) was observed in mean serum cortisol in AL (18.41 ± 2.17 ng/mL) or 36H (22.98 ± 2.17 ng/mL). Mean serum glucose was greater (P < 0.05) in 36H pens (78.15 ± 0.77 mg/dL) than AL (75.91 ± 0.77 mg/dL). Mean serum creatinine was greater (P < 0.05) in 36H pens (0.71 ± 0.03 mg/dL) than AL (0.60 ± 0.03 mg/dL). The 36H pens also displayed increased (P < 0.05) serum albumin, anion gap, Ca, Cl, Na, cholesterol, and aspartate aminotransferase over AL. Greater (P < 0.05) mean percentage BW loss was observed in 36H pens (5.2 ± 0.6%) than AL (3.1 ± 0.6%). Mean muscle protein (%) was greater (P < 0.05) in 36H (22.2 ± 0.4%) than 18H (21.3 ± 0.4%). Mean muscle moisture (%) was greater (P < 0.05) in AL and 18H (75.3 ± 0.4% and 75.2 ± 0.4%) than 36H. Mean 24-h pH values were 5.92 (AL), 5.92 (18H), and 5.81 (36H; SE = 0.04) and were not different (P < 0.05). Observed pH and color values indicated a borderline dark-cutter state across all cattle in the study, regardless of water and feed access treatment. Based on these results, water and feed withdrawal in lairage should not exceed 18 h during the marketing of Holstein slaughter cows acclimated to springtime conditions to maintain BW, serum component concentrations, and fresh meat composition.


Assuntos
Bem-Estar do Animal/normas , Peso Corporal/fisiologia , Bovinos/fisiologia , Privação de Alimentos/fisiologia , Carne/normas , Privação de Água/fisiologia , Animais , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Bovinos/sangue , Colesterol/sangue , Creatinina/sangue , Eletrólitos/sangue , Feminino , Hidrocortisona/sangue , Proteínas Musculares/metabolismo , Distribuição Aleatória , Albumina Sérica/análise , Wisconsin
6.
J Anim Sci ; 89(5): 1412-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21183712

RESUMO

Many small slaughter facilities use head-only electrical stunning to render swine unconscious and insensible to pain before slaughter. Head-only electrical stunning is a reversible procedure that is optimally effective for approximately 15 s after stun completion. In many small North American slaughter plants, the authors have observed hoist speeds that are too slow to achieve a short enough stun-to-bleed interval to maintain insensibility through exsanguination. Unlike many European plants, there is no separate high-speed hoist for pigs and exsanguination on the floor is not condoned. As a result, a 2-stage stunning method was proposed where head-only stunning for 3 s was immediately followed by application of the same stunning wand to the cardiac region of the animal for 3 s while lying in lateral recumbancy. A paired-comparison study was conducted on 89 pigs in a small slaughter facility to compare the head-only method applied for 6 s with the head/heart method. The objective was to evaluate signs of return to sensibility, stun-to-bleed time, blood lactate concentration, muscle pH, drip loss, and fresh meat color to validate the head/heart electrical stunning method for small slaughter plants. Incidence of corneal reflex was not different (P > 0.05) between head/heart (93.8%) and head only (85%) stunning. Nose twitching was more common (P < 0.05) in head only (26.5%) than head/heart (5%) stunning. Head/heart stunning eliminated rhythmic breathing, natural blinking, eye tracking to moving objects, and righting reflex, which were all observed in head-only stunned pigs. Eye tracking to moving objects was observed in 40.8% of head-only stunned pigs. Blood lactate was not different (P > 0.05) between stunning methods (head only: 8.8 ± 0.7 mmol/L, head/heart: 7.8 ± 0.7 mmol/L). Stun-to-bleed time did not differ (P > 0.05; head only: 32 ± 1 s, head/heart: 33 ± 1 s). Mean time to loss of heartbeat with the head-only method was 121 ± 5 s. No heartbeat was observed with the head/heart method. Longissimus thoracis pH, color, and drip loss were not different (P > 0.05) between stunning methods. This study determined that the head/heart electrical stunning method reduces the incidence of signs of return to sensibility without significant effects on meat quality, plant operation speed, or blood lactate concentration. In addition, the head/heart method requires no capital investment for plants that are currently using the head-only method.


Assuntos
Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Eletrochoque/veterinária , Carne , Suínos/fisiologia , Matadouros , Criação de Animais Domésticos/normas , Animais , Feminino , Masculino , Inconsciência
7.
J Anim Sci ; 87(6): 2089-95, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19251922

RESUMO

The objective of this work was to compare feedlot performance, carcass characteristics, and beef sensory attributes from steers finished with diets based on corn, high-tannin sorghum (HTS), and a mix of both grains. Angus crossbred steers (n = 11 steers per treatment, initial BW = 404 +/- 18 kg) were finished on diets containing 765 g/kg of DM of corn, HTS, or a 1:1 mix of corn and HTS. Final BW (P < 0.01), ADG (P < 0.001), and G:F (P < 0.01) were reduced in steers fed HTS when compared with steers fed corn. Steers fed the mixed diet had greater G:F than the average between corn and HTS diets (P = 0.04), which indicated that mixing corn and HTS had positive associative effects. Estimated NE(m) of HTS was 1.91, and estimated NE(g) was 1.35 Mcal/kg of DM. Hot carcass weight (P < 0.01), trimmed carcass weight (P < 0.01), yield grade (P = 0.04), and 12th-rib fat thickness (P = 0.01) were less in steers fed HTS than in those fed corn. Estimated percentage of HCW as boneless, closely trimmed retail cuts was greater in steers fed HTS compared with those fed corn (P = 0.02) but, due to the decreased HCW, estimated amount of boneless, closely trimmed retail cuts was less in steers fed HTS than in those fed corn (P = 0.03). Steers fed HTS had greater pH on LM (P = 0.02) than steers fed corn, but the difference was small (5.42 +/- 0.02 vs. 5.36 +/- 0.02, respectively) and within the range of normal beef pH. Diet had no effect on Warner-Bratzler shear values (P > or = 0.72). Multivariate ANOVA indicated a difference in sensory attributes of beef from corn and HTS steers (Wilks' Lambda, P = 0.04). When evaluating each sensory attribute independently, panelists found beef from steers fed HTS to be less juicy (P < 0.01), less tender (P = 0.03), and more cooked (P < 0.01) than beef from animals fed corn. Data from this study indicated that by using a 1:1 mix of HTS and corn it is possible to finish steers to similar BW and carcass quality as by using a corn-based diet. Also, total replacement of corn by HTS in the diets produced lighter and leaner animals. Total replacement of corn by HTS in the finishing diet changed beef sensory attributes, reducing the perception of beef tenderness and juiciness by panelists but without changing instrumental tenderness.


Assuntos
Ração Animal/análise , Dieta/veterinária , Carne/normas , Sorghum/química , Zea mays/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Peso Corporal , Bovinos , Masculino
8.
Meat Sci ; 77(4): 492-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22061933

RESUMO

Calcium chloride (250, 500ppm) was examined for its ability to reduce the pink color defect induced by sodium nitrite (10ppm) and nicotinamide (1.0%) in cooked ground turkey in the presence and absence of sodium tripolyphosphate (0.25, 0.5%) and sodium citrate (0.5, 1.0%). The ability of tricalcium phosphate (0.1-0.5%) to reduce pink cooked color also was evaluated in ground turkey and both calcium chloride and tricalcium phosphate were tested for their effects on pink cooked color in whole breast muscle. The combination of calcium chloride and sodium tripolyphosphate, not calcium chloride alone, was necessary for a reduction in pink cooked color induced by nicotinamide. Subsequently, in the presence of phosphate, both calcium chloride and sodium citrate reduced pink cooked color and were most effective in combination. Tricalcium phosphate also was capable of reducing pink cooked color in ground turkey, however substituting tricalcium phosphate for sodium tripolyphosphate resulted in lower pH and cooking yields. Neither calcium chloride nor tricalcium phosphate was capable of reducing pink cooked color in whole turkey breast. Currently, a combination of sodium tripolyphosphate, calcium chloride, and sodium citrate represents the most suitable means for reducing or preventing the pink color defect in uncured ground turkey.

9.
Meat Sci ; 77(4): 529-39, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22061938

RESUMO

Whey protein concentrate constituents were tested for their ability to reduce naturally occurring pink color defect and pink cooked color induced by sodium nitrite (10ppm) and nicotinamide (1.0%) in ground turkey. ß-lactoglobulin (1.8%), α-lactalbumin (0.8%), bovine serum albumin (0.15-0.3%), lactose (1.0-3.0%), potassium chloride (500-1500ppm), and ferrous iron chloride (0.3-30ppm) had no effects on cooked pink color. Lactoferrin (30-5000ppm) increased or decreased pink color depending on its concentration in samples without added sodium nitrite or nicotinamide. Annatto (0.1-1.0ppm) reduced pink color whereas the higher concentration of magnesium chloride (22-88ppm) and ferric iron chloride (0.3-30ppm) increased pink color in samples with added nicotinamide. Calcium chloride (160-480ppm) was the only tested constituent that consistently reduced pink cooked color in samples with and without added nitrite and nicotinamide. Due to the variability of whey protein concentrates and the number of constituents that do not reduce pink cooked color, the addition of calcium alone or dried milk minerals containing calcium, phosphate, and citrate, represents a better means to regularly prevent the pink color defect in cooked ground turkey.

10.
Meat Sci ; 72(3): 567-73, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22061742

RESUMO

The effects of citric acid (0.15%, 0.3%) and sodium citrate (0.5%, 1.0%) on pink color development in ground turkey following irradiation (0, 2.5, 5.0kGy) were examined. Citric acid and sodium citrate had little effect on pink color when samples were irradiated prior to cooking. In contrast, when samples were cooked prior to irradiation, citric acid (0.3%) and sodium citrate (1.0%) reduced redness as indicated by eliminating a reflectance minimum at approximately 571nm, lessening greater reflectance in the red wavelength region, and preventing greater reducing conditions caused by irradiation. Citric acid significantly reduced pH and yields whereas sodium citrate reduced pH and yields to a lesser extent. Both citric acid and sodium citrate are potential ingredients that can be added during processing to prevent undesirable pink color in precooked irradiated ground turkey and therefore can result in greater acceptance of irradiated products by consumers.

11.
Meat Sci ; 72(4): 585-95, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22061868

RESUMO

The principal mechanism by which sodium citrate reduces the pink color defect in cooked ground turkey was investigated. Sodium citrate (SC; 0, 0.125, 0.25, 0.5, 1.0, 2.0M), sodium nitrite (0.01, 0.1M), and nicotinamide (0.5, 0.75M) were combined in solutions of bovine hemin to determine SCs ability to bind heme iron and competitively inhibit pink-color-generating ligands from binding. Additionally, the effects of sodium erythorbate (0, 275, 550ppm), ferrous iron chloride (0, 0.3, 3.0, 30ppm), and ferric iron chloride (0, 0.3, 3.0, 30ppm) on SCs ability to reduce pink cooked color was examined. Absorbance curves of hemin+nitrite and hemin+nicotinamide were relatively unaffected by SC, therefore whether or not SC bound heme iron, that did not appear to be a mechanism for inhibiting the pink color defect. Both ferrous and ferric iron chloride had minimal effects on color values, possibly due to sodium tripolyphosphate chelation ability in the meat system and thus their presence did not enhance SCs ability to reduce the pink color defect. However, sodium erythorbate, a reducing agent, inhibited SCs ability to decrease the pink color defect in samples induced pink with sodium nitrite and nicotinamide. Therefore, it appears SC requires the presence of oxygen and may participate in oxidative processes to reduce the pink color defect.

12.
Meat Sci ; 73(2): 287-94, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22062300

RESUMO

Three methods were examined for preserving pre-rigor meat functionality in beef patties. Hot-boned semimembranosus muscles were processed as follows: (1) pre-rigor ground, salted, patties immediately cooked; (2) pre-rigor ground, salted and stored overnight; (3) pre-rigor injected with brine; and (4) post-rigor ground and salted. Raw patties contained 60% lean beef, 19.7% beef fat trim, 1.7% NaCl, 3.6% starch, and 15% water. Pre-rigor processing occurred at 3-3.5h postmortem. Patties made from pre-rigor ground meat had higher pH values; greater protein solubility; firmer, more cohesive, and chewier texture; and substantially lower cooking losses than the other treatments. Addition of salt was sufficient to reduce the rate and extent of glycolysis. Brine injection of intact pre-rigor muscles resulted in some preservation of the functional properties but not as pronounced as with salt addition to pre-rigor ground meat.

13.
Poult Sci ; 82(7): 1205-10, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12872981

RESUMO

The top surface of boneless skinless chicken breasts was inoculated with either green fluorescent protein (GFP)-labeled Escherichia coli (E. coli-GFP) or rifampicin-resistant E. coli (E. coli-Rif) and subjected to electrically generated hydrodynamic shock wave treatment (HVADH). Cryostat sampling in concert with laser scanning confocal microscopy or plating onto antibiotic selective agar was used to determine if HVADH treatment resulted in the movement of the inoculated bacteria from the outer inoculated surface to the interior of intact boneless skinless chicken breasts. In HVADH-treated boneless skinless chicken breasts, marker bacteria were detected within the first 200 microm below the inoculated surface, 50 to 100 microm beyond the depth of untreated surface inoculated boneless skinless chicken breasts. The exact depth at which the marker bacteria were found was dependent on the cryostat sampling distance used. These results suggest that HVADH treatments affect the movement of surface bacteria.


Assuntos
Galinhas , Estimulação Elétrica , Escherichia coli/fisiologia , Tecnologia de Alimentos , Carne/microbiologia , Animais , Conservação de Alimentos , Congelamento , Expressão Gênica , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Microscopia Confocal , Músculo Esquelético/microbiologia , Manejo de Espécimes
14.
Meat Sci ; 65(4): 1293-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22063772

RESUMO

The ability of whey protein concentrates (WPCs) to reduce pink color in cooked ground turkey was investigated. Ground turkey was formulated with no ligand and nitrite and nicotinamide to induce pinking. Five WPCs with 34 or 80% protein were tested and turkey samples were cooked to 80 and 85 °C and stored for 1 and 7 days. Three WPCs reduced a* values in turkey without added nitrite or nicotinamide and one WPC reduced nitrite induced pinking. In nicotinamide-induced pink turkey, two WPCs reduced a* values and two WPCs increased pink color. Nitrosylhemochrome was reduced by two WPCs and nicotinamide hemochrome was reduced by one WPC and increased by two WPCs. Increased cooking temperatures enhanced inhibitory effects or reduced reddening effects of two WPCs. Storage time and protein content had minimal effects on pink color. Whey protein concentrates have the potential to reduce the pink defect in cooked uncured turkey, although the mechanism is unclear.

15.
J Food Prot ; 65(4): 616-20, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11952209

RESUMO

The top surface of the raw eye of round steaks was inoculated with either green fluorescent protein (GFP)-labeled Escherichia coli (E. coli-GFP) or rifampin-resistant E. coli (E. coli-rif). Cryostat sampling in concert with laser scanning confocal microscopy (LSCM) or plating onto antibiotic selective agar was used to determine if hydrodynamic shock wave (HSW) treatment resulted in the movement of the inoculated bacteria from the outer inoculated surface to the interior of intact beef steaks. HSW treatment induced the movement of both marker bacteria into the steaks to a maximum depth of 300 microm (0.3 mm). Because popular steak-cooking techniques involve the application of heat from the exterior surface of the steak to achieve internal temperatures ranging from 55 to 82 degrees C, the extent of bacterial penetration observed in HSW-treated steaks does not appear to pose a safety hazard to consumers.


Assuntos
Escherichia coli O157/fisiologia , Carne/microbiologia , Animais , Bovinos , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Culinária/métodos , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes , Carne/análise , Microscopia Confocal , Rifampina/farmacologia
16.
Meat Sci ; 58(3): 283-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22062257

RESUMO

Eighty early deboned (45 min, post mortem) postrigor chicken breasts were exposed (24 h post mortem) to two levels (number of pulse firing networks, PFN; 45% energy) of electrically produced hydrodynamic shockwaves (HSW). In addition, 21 turkey breasts (72 h post mortem) were HSW treated (two PFN, 72% energy). Samples were water cooked in bags (78°C internal). Two PFN's were required to decrease (P<0.05) chicken Warner-Bratzler shear (WBS) force by 22% from the control (4.67 kg). WBS force of the HSW treated turkey breast decreased (P<0.05) by 12% from the control (3.20 kg). Cooking loss was higher (P<0.05) in the turkey breast portions but not in the chicken breasts. The electrically produced shockwave process has the potential to provide chicken processors with the ability to early debone and produce tender breasts and to provide turkey processors with tenderness-enhanced fillets.

17.
Meat Sci ; 58(3): 287-92, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22062258

RESUMO

In separate experiments, chicken broiler breasts were deboned (45 min postmortem, 52 min, respectively) and either exposed to high pressure hydrodynamic shockwaves (HSW) 25 min after deboning (77 min postmortem) or after 24 h of storage (4°C) respectively, and compared to companion control breasts. HSW were produced in a cylindrical HSW processor with 40-g explosive. Warner-Bratzler shear (WBS) values of the HSW breasts treated at 77 min postmortem were not different than the controls. HSW treatment decreased (P<0.05) the WBS values of the stored and cooked breasts by 42.0% as compared to non-treated controls. Cooking losses were not affected by HSW. In general, raw and cooked color characteristics (CIE L*a*b*) were not affected by the HSW. HSW treatment at 25 min after deboning (77 min postmortem) may require a higher pressure front or delayed treatment after postmortem aging to improve tenderness.

18.
J Food Prot ; 63(11): 1511-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11079692

RESUMO

The ability of nonproteolytic Clostridium botulinum type B spores to grow and produce toxin in cooked, uncured turkey packaged under modified atmospheres was investigated at refrigeration and mild to moderate abuse temperatures. Cook-in-bag turkey breast was carved into small chunks, surface-inoculated with a mixture of nonproteolytic C. botulinum type B spores, packaged in O2-impermeable bags under two modified atmospheres (100% N2 and 30% CO2:70% N2), and stored at 4, 10, and 15 degrees C. Samples were analyzed for botulinal toxin and indigenous microorganisms, as well as subjected to sensory evaluation, on days 0, 7, 14, 28, 42, and 60. Given sufficient incubation time, nonproteolytic C. botulinum type B grew and produced toxin in all temperature and modified atmosphere treatment combinations. At moderate temperature abuse (15 degrees C), toxin was detected by day 7, independent of packaging atmosphere. At mild temperature abuse (10 degrees C), toxin was detected by day 14, also independent of packaging atmosphere. At refrigeration temperature (4 degrees C), toxin was detected by day 14 in product packaged under 100% N2 and by day 28 in product packaged under 30% CO2:70% N2. Reduced storage temperature significantly delayed toxin production and extended the period of sensory acceptability of cooked turkey, but even strict refrigeration did not prevent growth and toxigenesis by nonproteolytic C. botulinum. At all three storage temperatures, toxin detection preceded or coincided with development of sensory characteristics of spoilage, demonstrating the potential for consumption of toxic product when spoilage-signaling sensory cues are absent.


Assuntos
Toxinas Botulínicas/biossíntese , Clostridium botulinum/metabolismo , Conservação de Alimentos , Aves Domésticas/microbiologia , Temperatura , Animais , Clostridium botulinum/crescimento & desenvolvimento , Microbiologia de Alimentos , Esporos Bacterianos/crescimento & desenvolvimento , Paladar , Fatores de Tempo , Perus
19.
Poult Sci ; 79(1): 126-36, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10685900

RESUMO

Our first objective was to determine the effects of explosive amount and distance of the explosive to the meat surface in the Hydrodyne process on broiler breast tenderness. Early deboned (EB) breasts were removed immediately after initial chill (45 min postmortem), stored for 24 h (4 C), and subjected to one of four Hydrodyne treatments (200 g at 20 cm, 350 g at 23 cm, 275 g at 20 cm, or 350 g at 20 cm). Breasts were water-cooked (78 C internal). Hydrodyne treatment (HYD) of 350 g at 20 cm produced the greatest reduction (28.3%) in Warner-Bratzler shear (WBS, 1.9-cm wide strips). This combination was the only treatment to improve tenderness (peak force 4.3 kg) to a level equivalent (P > 0.05) to aged controls (CA; peak force 3.1 kg). The second objective was to determine the quality and sensory characteristics of Hydrodyne-treated (350 g explosive at 20 cm) broiler breasts as compared with CA and EB. The WBS values (1.0-cm wide and thick strips) for CA (1.56 kg) were different from both HYD (3.7 kg) and EB breasts (4.7 kg). The CA resulted in more tender, flavorful, and juicer breasts than EB and HYD. The EB was higher in initial moisture release than HYD. The EB breasts with tenderness problems can be tenderized by the Hydrodyne process based on WBS results. However, higher levels of explosive may be required to optimize the tenderness improvement of EB breasts that vary significantly in initial tenderness.


Assuntos
Manipulação de Alimentos , Carne , Sensação , Animais , Galinhas , Cor , Temperatura Alta , Controle de Qualidade , Reologia
20.
Poult Sci ; 78(2): 255-66, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10051039

RESUMO

Nonmeat ingredients were tested for their ability to inhibit pink color (which consumers associated with undercooking) in turkey breasts with and without added pink color generating agents (1.0% nicotinamide; 20, 100 ppm nitrite). Nonmeat ingredients included: trans 1,2-diaminocyclohexane-N,N,N',N' tetraacetic acid monohydrate (CDTA), diethylenetriamine pentaacetic acid (DTPA), ethylenedinitrilotetraacetic acid disodium salt (EDTA), and nonfat dried milk (NFDM). Ingredients were evaluated at two (1%, 2% NFDM) or three different levels (50 ppm, 100 ppm, 200 ppm; EDTA, DTPA, and EDTA), over three storage times (1, 4, 21 d), and after 2 min of exposure to light and air. Whole muscle turkey strips were injected with a 20% treatment solution. Product was tumbled and heat processed to an internal temperature of 80 C. Turkey muscle strips containing ingredients without pink color generating agents were less red and lighter than controls. In most cases, 50 ppm of added EDTA, CDTA, or DTPA was sufficient to reduce pinking. Ingredients were more effective against nicotinamide- than nitrite-generated pink. Overall, ingredients delayed onset of pink color associated with storage time. In general, DTPA was the most effective of the test ingredients. However, as NFDM is both effective at reducing the pink defect and approved as a nonmeat ingredient, processors can incorporate this ingredient for the benefit of reducing this defect. Future studies should determine how NFDM achieves this reduction.


Assuntos
Aditivos Alimentares , Manipulação de Alimentos , Carne/normas , Animais , Quelantes/farmacologia , Cor , Comportamento do Consumidor , Culinária , Leite , Ácido Pentético/farmacologia , Perus
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