-
[show abstract]
[hide abstract]
ABSTRACT: Advantages of air chilling (AC) methods over immersion chilling (IC) methods in quality retention and improvement of deboned chicken breast meat depend on experimental conditions, such as deboning time. The objective of this study was to evaluate the effect of a dry-AC method on shear force and water-holding capacity (WHC) of broiler breast meat deboned 4h postmortem compared to hot-boned (no chill) or immersion-chilled meat. Ready-to-cook broiler carcasses were hot-boned, chilled by ice water immersion (0.3 °C, 50 min) or chilled by cross-flow cold, dry air (0.7 °C, 150 min). Pectoralis (p.) major and p. minor were removed from the bone at 4 h postmortem. Shear force was measured using a Warner-Bratzler (WB) method and WHC was estimated using cooking yield, drip loss, amount of bound water (filter paper method) and water uptake (swell/centrifugation method). Regardless of muscle type, the WB shear force value of AC samples was significantly lower than that of hot-boned samples; however, there was no difference in the shear force between AC and IC. Regardless of measurement methods, there were no differences (P > 0.05) in WHC between the three treatments. These results demonstrate that when compared to no chill, AC followed by 4 h postmortem deboning can lead to a difference in WB shear values while WHC properties can be retained. For broiler breast meat deboned 4 h postmortem, AC does not result in any significant differences in shear force and WHC when compared to IC.
International Journal of Poultry Science. 01/2008;
-
[show abstract]
[hide abstract]
ABSTRACT: Broiler processing may result in fecal contamination of the surfaces of carcasses. Fecal contaminants on broiler carcasses are prohibited due to the potential presence of bacterial pathogens. The objective of this study was to determine the effectiveness of the hyperspectral imaging system to detect cecal contamination of known mass. On each of three replicate sample days, twenty-four eviscerated, pre-chilled broiler carcasses were collected from a commercial processing plant. Broiler carcasses were cut longitudinally into contra-lateral halves using a sanitized saw. Cecal contents from the same flock were also collected and used to contaminate carcass. Contents of multiple cecal were combined, homogenized and used to contaminate carcass. Carcass halves were imaged uncontaminated and cecal contents (10, 50, or 100 mg) were applied to the carcass half, and then re-imaged. Cecal detection results varied due to contaminate detection threshold. The imaging system correctly identified 100% cecal mass applied at a threshold of 1.00 and 1.05 but also incorrectly identified 252 and 65 carcass features, respectively that were not contaminates (false positives). False negative were only associated with the 10mg mass and a detection threshold of 1.10. The percentage of true positive cecal pixels (ie. ground truth) detected also varied due to the detection threshold. Averaged across cecal mass, the percentage of the cecal ground truth detected was 74, 55 and 35% for the 1.00, 1.05 and 1.10 threshold, respectively. The percentage of contaminated pixels not detected were a spectral mixture of cecal and uncontaminated skin. Detection of mixed pixels in small contaminants (ie. 10mg and less) or an aggregate of several single-pixels is essential for contaminant identification. Detection of mixed pixels in large contaminants is not significant to overall contaminant identification.
International Journal of Poultry Science. 01/2005;
-
[show abstract]
[hide abstract]
ABSTRACT: Lactic-acid-producing bacterial cultures were applied to the skin of live broilers 24 hours before slaughter to determine whether inoculation with the cultures could affect the numbers of bacteria that are normally found on the skin of processed broiler carcasses. The cultures contained 10,000 to 100,000 cfu/mL and were suspended in 250 mL of a pH 6.0 nutrient medium (including glucose, peptone, beef extract, yeast extract, a surfactant, and salts) intended to enhance the survival and growth of the cultures. With broilers suspended by the feet, feathers were moved aside and the liquid suspension was sprayed directly on the skin. Sprayed broilers were then returned to a pen. In each of three replications, 4 six-wk-old broilers were sprayed and 4 broilers were kept as untreated controls. The following day, broilers were processed in a research processing facility and defeathered carcasses were sampled by rinsing for 1 min in 200 mL of peptone water after removal of heads and feet. Coliforms, E. coli , lactic-acid bacteria, and Campylobacter in carcass rinses were enumerated by standard methods. After removal of aliquots for plating, the remaining sample volume was enriched to detect Salmonella . No differences were found in log<SUB>10</SUB>(cfu/mL) of coliforms, E. coli , or lactic-acid bacteria between the treated and control carcasses. Salmonella bacteria were present on some carcasses, but with no difference between treatments. Campylobacter spp. were present in only one replication, so numbers of Campylobacter could not be analyzed statistically. Spraying lactic-acid-producing bacteria with nutrients on the skin of live broilers on the day before processing appears to have no effect on numbers of bacteria that are present on the skin after defeathering.
International Journal of Poultry Science. 01/2005;
-
[show abstract]
[hide abstract]
ABSTRACT: Campy-Line agar, was compared to Campy-Cefex agar for recovery of Campylobacter spp. Five samples were examined from each of 18 broiler carcasses including: feathers, skin, crop, ceca and colon. An additional 16 rinse samples from fresh fully processed commercial broiler carcasses were also examined. Campy-Line agar provided Campylobacter spp. counts that closely mirrored those found by enumeration on Campy-Cefex agar. Campy-Cefex agar generally provided slightly higher counts (P < 0.05) for all sample types except skin. However, Campylobacter populations recovered with Campy-Line agar were correlated with those recovered using Campy-Cefex agar; correlation coefficient values were 0.94 for feathers, 0.95 for skin, 0.98 for crop, 0.87 for ceca and 0.88 for colon samples. Observations suggest that Campy-Line agar is easier to use due to the virtual absence of contaminating colonies.
International Journal of Poultry Science. 01/2005;
-
[show abstract]
[hide abstract]
ABSTRACT: The contents of the upper digestive tract (i.e. crop, proventriculus and gizzard) may serve as a source of carcass contamination during broiler processing. The crop as been identified as a source of Salmonella and Campylobacter on contaminated carcasses and is more likely to rupture than the ceca during commercial evisceration. The objective of this study was to determine the effectiveness of hyperspectral imaging for detecting ingesta contamination spots varying in mass from the crop and gizzard. Pre-chilled broiler carcasses were collected from a commercial processing plant. Crop and gizzard contents were also aseptically collected and enumerated for Campylobacter , coliforms, E. coli and total aerobic bacteria. Broiler carcasses were imaged and then contaminated with a spot of known mass (10, 50, or 100 mg) of crop or gizzard contents. Carcasses were then re-imaged. The imaging system correctly detected 100% of the crop and gizzard contents regardless of the mass or spot size. However, not every pixel associated with a given spot (contaminant ground truth) was detected. Detection of crop and gizzard content contaminant ground truth pixels averaged 72 and 53%, respectively. The mean number of bacteria in the crop contents were as follows: E. coli 4.0 log, coliforms 4.1 log, and total aerobic bacteria 5.7 log CFU/g of crop contents. Crop contents in the current study were Campylobacter negative. Applying crop contents in the amounts of about 9, 54, and 231 mg resulted in significant (P< 0.05) increases in all bacterial population measured, with the biggest increase being noted for total aerobic bacteria. Gizzard contents contained only 4.6 log CFU/g of total aerobic bacteria. The total added bacterial load from contamination with known amounts of crop and gizzard contents did not significantly increase whole carcass counts of all bacteria enumerated. Based on these counts and numbers of bacteria found in gizzard, carcass contamination with visible ingesta does not appear to significantly increase bacterial load.
International Journal of Poultry Science. 01/2005;
