Volatile Flavor Compounds Vary by Beef Product Type and Degree of Doneness

This study aimed to determine how quality grade and degree of doneness (DOD) influence the development of volatile compounds among beef whole muscle and ground patties. Volatile compounds were quantified via head space solid phase microextraction from samples tempered in refrigerated temperatures (3 to 5 °C), room temperature (24 to 26 °C), or cooked on an electric clamshell-style grill to an endpoint temperature of 55, 60, 71, or 77 °C. Collected samples were subsequently determined by gas chromatography mass spectrometry. Prominent compounds known to be the result of the Maillard reaction or lipid degradation were retained for comparison. Four Strecker aldehydes, 4 pyrazines, and one ester had a 3-way interaction between quality grade, DOD, and product type (each P \u3c 0.001). Pyrazine concentrations did not differ (P \u3e 0.05) in ground patties and was comparably greater (P \u3c 0.05) in steaks; in Prime and Low Choice steaks, pyrazine concentration increased (P \u3c 0.05) as DOD increased. A 2-way interaction between quality grade and product type was observed for acetaldehyde, dimethyl disulfide, 1-penten-3-ol, butanoic acid, hexanal, octanal, nonanal, and 2-heptanone. Among which, octanal and nonanal were greater (P \u3c 0.05) in Prime steaks compared with ground patties. Another 2-way interaction, quality grade and DOD, was observed in 2 ketones, an alcohol, 2 esters, and 2 aldehydes. For example, 2,3-butanedione was greater (P \u3c 0.05) in concentration in Prime 4 °C samples compared with Low Choice and Standard. The final 2-way interaction of DOD and product type was observed in 3 ketones, 2 sulfur compounds, 2 esters, 5 aldehydes, 2 carboxylic acids, and a ketone. For example, 2-heptanone was greater (P \u3c 0.05) in concentration in ground patties compared to steaks in all degrees of doneness except 4 °C. Overall, these results indicate that the volatile flavor profile of beef is greatly influenced by product type and DOD. Generally, consumers select beef based on product type and determine their cookery approach. Therefore, consumers may greatly influence final beef flavor profile

Study of Greenbug Resistance - in Sorghum Pi220248

Agronom

Effect of Production Method on Characteristics and Oxidative Stability of Microencapsulated Fish Oil

The main objective of this study is to evaluate the effect of fish oil microencapsulation method on characteristics and oxidative stability. Four methods, freeze drying, spray drying by a 2 fluid pressure nozzle, spray drying by a 3 fluid pressure nozzle, and spray drying by a 2 channel ultrasonic nozzle were used in this research. Surface morphology of the microcapsules where determined by scanning electron microscopy. Total oil of the microcapsules was determined by soxtec and Rose-Gottlieb solvent extraction methods. Solvent extractable surface oil was also determined. Size of the microcapsules was determined by particle size analysis. Moisture content of the microcapsules was determined by Karl Fischer titration. Oxidative stability of the microcapules was determined over a 15 week period in which HS-SPME was used to analyze volatile oxidative compounds by GC-MS. Comparison of chemical and physical characteristics revealed some differences. With regard to uniformity of size and shape, microcapsules produced by the2-channel ultrasonic nozzle were observed to be more uniform in size and shape, determined by particle size distribution and SEM image comparisons. Disadvantages were also observed for ultrasonic nozzle microcapsules having lower oil encapsulating efficiency compared to pressure nozzles and freeze dried microcapsules. There was no observed initial advantage to spray methods that did not require the creation of an emulsion for microcapsule production. However, it was observed that microcapsules produced by multi-fluid nozzles propanal levels were lower throughout the course of a 14 week stability test. It should be stated that the 15 week sampling period may not have been long enough to adequately observe the induction of oxidation for all samples stored in the conditions chosen. Sample values fluctuated within a moderate range throughout the entire study. However, byobserving propanal levels at the last data point of the stability study some conclusions may be drawn. At the end of the 5 �C test PAR levels for fish oil and freeze dried samples were observed to have a significant increase while spray dried samples values remained steady. This may indicate the beginning of oxidation among the fish oil and freeze dried samples while spray dried samples were remaining stable.Department of Animal Scienc

Tannins in Perennial Legume and Forb Functional Forages

Feed is the greatest input cost for cattle producers. The studies summarized here employed non-bloating, tannin-containing irrigated perennial legume pastures or hay of legumes or a hydrolysable tannin-containing forb that were grown in the Mountain West USA, with non-tannin legume, grass, or feedlot treatments for comparison. Cattle grazing legume pastures or fed legume or forb hays had greater intake, gain and nitrogen retention, and in some cases, reduced enteric methane emissions compared with grass pastures or hay, and methane emissions were not different from feedlot-fed cattle

Consumer palatability scores and volatile beef flavor compounds of five USDA quality grades and four muscles

Proximate data, consumer palatability scores and volatile compounds were investigated for four beef muscles (Longissimus lumborum, Psoas major, Semimembranosus and Gluteus medius) and five USDA quality grades (Prime, Upper 2/3 Choice, Low Choice, Select, and Standard). Quality grade did not directly affect consumer scores or volatiles but interactions (P < 0.05) between muscle and grade were determined. Consumer scores and volatiles differed (P < 0.05) between muscles. Consumers scored Psoas major highest for tenderness, juiciness, flavor liking and overall liking, followed by Longissimus lumborum, Gluteus medius, and Semimembranosus (P < 0.05). Principal component analysis revealed clustering of compound classes, formed by related mechanisms. Volatile n-aldehydes were inversely related to percent fat. Increases in lipid oxidation compounds were associated with Gluteus medius and Semimembranosus, while greater quantities of sulfur-containing compounds were associated with Psoas major. Relationships between palatability scores and volatile compound classes suggest that differences in the pattern of volatile compounds may play a valuable role in explaining consumer liking

Influence of Maternal Protein Restriction in Primiparous Heifers During Mid- and/or Late-gestation on Meat Quality and Fatty Acid Profile of Progeny

The objective of this study was to evaluate the influence of metabolizable protein (MP) restriction in mid- and/or late-gestation on meat quality, fatty acid profile, and carcass composition of progeny

Consumer Sensory Evaluation and Chemical Composition of Beef Gluteus Medius and Triceps Brachii Steaks from Cattle Finished on Forage or Concentrate Diets

The objective of this study was to assess the impact of cattle finishing diet and muscle type on meat quality. Consumer sensory response, proximate composition, Warner–Bratzler shear force (WBSF), fatty acid composition, and volatile compounds were assessed from the gluteus medius (GM) and triceps brachii (TB) muscles of cattle (n = 6 per diet) which were grain-finished (USUGrain) on conventional feedlot or 2 forage diets, a perennial legume, birdsfoot trefoil-fin-ished (USUBFT; Lotus corniculatus), and grass-finished (USUGrass; Bromus riparius). Diet had an interacting effect with muscle for all sensory attributes (P ≤ 0.002), except aroma and flavor (P ≥ 0.078). In forage-finished beef, tenderness, fattiness, overall liking, and WBSF tenderness of GM was greater (P \u3c 0.05) than TB, whereas for USUGrain, the tenderness, fattiness, overall liking, and WBSF tenderness of both muscles were similar (P \u3e 0.05) but the juiciness of TB was more liked than USUGrain GM (P \u3c 0.05). The juiciness of forage-finished beef did not differ (P \u3e 0.05) between GM and TB. Lower (P \u3c 0.05) intramuscular fat (IMF) percent was determined for USUGrass beef in comparison with USUGrain beef. The IMF percent of USUBFT beef was similar (P \u3e 0.05) to both USUGrass and USUGrain beef. However, IMF percent was not impacted by muscle type (P = 0.092). The ratio of n-6:n-3 fatty acids was affected by muscle dependent on diet (P = 0.016). The ratio of n-6:n-3 fatty acids was affected by the interaction of muscle × diet (P = 0.016). Between forage diets (USUGrass and USUBFT), n-6:n-3 ratios were similar (P \u3e 0.05) between GM and TB, whereas within USUGrain, the GM was greater (P \u3c 0.05) than the TB. Cumulative MUFA was greater (P \u3c 0.05) in USUGrain compared with both USUGrass and USUBFT, which were similar (P \u3e 0.05). Strecker aldehydes, ketones, pyrazines, and methional were affected (P ≤ 0.036) by muscle and found to have a greater concentration in GM compared with TB. Overall, consumers determined that USUGrain GM and TB had similar (P \u3e 0.05) quality ratings. However, within forage-finished beef, the GM was perceived more frequently (P \u3c 0.05) to be of premium quality and the forage-finished TB was more frequently (P \u3c 0.05) rated as having unsatisfactory quality. These findings were in agreement with ratings of tenderness and overall liking. Therefore, in the context of our consumer group grilled GM and TB steaks, grain-finished beef provided more uniform quality and eating experience compared with forage-finished beef

Metaphylactic antimicrobial effects on occurrences of antimicrobial resistance in \u3ci\u3eSalmonella enterica, Escherichia coli\u3c/i\u3e and \u3ci\u3eEnterococcus\u3c/i\u3e spp. measured longitudinally from feedlot arrival to harvest in high-risk beef cattle

Aims: Our objective was to determine how injectable antimicrobials affected populations of Salmonella enterica, Escherichia coli and Enterococcus spp. in feedlot cattle. Methods and Results: Two arrival date blocks of high-risk crossbred beef cattle (n = 249; mean BW = 244 kg) were randomly assigned one of four antimicrobial treatments administered on day 0: sterile saline control (CON), tulathromycin (TUL), ceftiofur (CEF) or florfenicol (FLR). Faecal samples were collected on days 0, 28, 56, 112, 182 and study end (day 252 for block 1 and day 242 for block 2). Hide swabs and subiliac lymph nodes were collected the day before and the day of harvest. Samples were cultured for antimicrobial-resistant Salmonella, Escherichia coli and Enterococcus spp. The effect of treatment varied by day across all targeted bacterial populations (p ≤ 0.01) except total E. coli. Total E. coli counts were greatest on days 112, 182 and study end (p ≤ 0.01). Tulathromycin resulted in greater counts and prevalence of Salmonella from faeces than CON at study end (p ≤ 0.01). Tulathromycin and CEF yielded greater Salmonella hide prevalence and greater counts of 128ERYR E. coli at study end than CON (p ≤ 0.01). No faecal Salmonella resistant to tetracyclines or third-generation cephalosporins were detected. Ceftiofur was associated with greater counts of 8ERYR Enterococcus spp. at study end (p ≤ 0.03). By the day before harvest, antimicrobial use did not increase prevalence or counts for all other bacterial populations compared with CON (p ≥ 0.13). Conclusions: Antimicrobial resistance (AMR) in feedlot cattle is not caused solely by using a metaphylactic antimicrobial on arrival, but more likely a multitude of environmental and management factors

ACC/AHA Guidelines for Coronary Angiography. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography)

"The ACC/AHA Task Force on Practice Guidelines herein revises and updates the original “Guidelines for Coronary Angiography,” published in 1987 (1). The frequent and still-growing use of coronary angiography, its relatively high costs, its inherent risks and the ongoing evolution of its indications have given this revision urgency and priority. The expert committee appointed included private practitioners and academicians. Committee members were selected to represent both experts in coronary angiography and senior clinician consultants. Representatives from the family practice and internal medicine professions were also included on the committee. The English-language medical literature was searched for the 10 years preceding development of the guidelines. The searches yielded >1,600 references that the committee reviewed for relevance. Evidence relative to the use of coronary angiography was compiled and evaluated by the committee. Whereas randomized trials are often available for reference in the development of treatment guidelines, randomized trials regarding the use of diagnostic procedures such as coronary angiography are rarely available (2). For development of these guidelines, when coronary angiography was a necessary procedure in describing a clinical subset or in choosing a course of treatment and that therapy was shown to have an advantage for the patient, especially in the context of a randomized trial, then the indication for angiography was given greater consideration than indications cited in less-rigorous evaluations of data.

Degree of Oxidation of Sonicated Soybean Oil Using Various Sonication Process Parameters

The purpose of this research was to evaluate the effect of High-intensity ultrasound (HIU) on soybean oil (SBO) using various sonication process conditions including different power level, probe diameter, pulse duration and amounts of sample. The highest power density and power intensity were observed with the highest HIU setting (setting 9) with 3.2 mm tip. No significant difference was obtained in peroxide value (PV) and oil stability index (OSI). th results of volatile compounds analysis showed that the highest power intensity values were associated with the oxidation of SBO. These results showed that HIU did not affect the degree of oxidation of sonicated SBO under mild conditions