Inside Round Research Articles

Intramuscular variation in mitochondrial functionality of beef <i>semimembranosus</i>

Intramuscular color stability variations in beef semimembranosus have been reported previously. Mitochondria remain biochemically active in postmortem muscle and can influence fresh beef color stability. However, the role of mitochondrial functionality in intramuscular color variations in beef semimembranosus is yet to be examined. We examined the functionality of mitochondria isolated from outside (OSM) and inside (ISM) regions of beef semimembranosus. Semimembranosus muscles (n = 5) were collected from inside rounds of beef carcasses 48 h post-mortem and were separated to OSM and ISM steaks. Color attributes were evaluated instrumentally and biochemically on days 0 and 4 of retail display, whereas mitochondrial oxygen consumption rate (OCR) was measured on day 0 using succinate as substrate using steaks frozen during fabrication. Mitochondrial OCR was significantly greater in OSM than in ISM on day 0. The ISM steaks exhibited significantly greater redness (a* value) than OSM steaks on day 0, but OSM steaks had significantly greater redness than the ISM counterparts on day 4. During retail display, ISM steaks exhibited greater lightness (L* value) than OSM steaks. However, OSM demonstrated significantly greater color stability and metmyoglobin reducing activity than ISM throughout the display. The observed differences in mitochondrial OCR between ISM and OSM steaks indicated that mitochondrial biochemistry possibly contributes to the intramuscular color variations in beef semimembranosus.Keywords: Beef color, color stability, mitochondria, semimembranosus

Honduran Production Systems and Dietary Impacts on Beef Carcass and Offal Yields and Value

ObjectivesHaving been once the largest exporter in CA for beef to the U.S., Honduras had a dramatic decrease in efficiency and production numbers due to a devastating hurricane in 1998. The purpose of this study was to measure dietary impacts on beef carcass and offal yields and value.Materials and MethodsFaculty from Texas Tech University worked alongside with Honduran cattle producers to develop feeding trials with specific diets for each producer. Feedstuffs in each diet were determined by local availability and price. A total of five new finishing programs were established with an additional grass finished program as control. The six treatments were: dried distillers grains (DDG), palm kernel meal (PKM), sugarcane (SC), soybean meal and corn (SBMC), sorghum (SORG), and grass fed (GF). Bos indicus crossbred cattle were utilized and harvest yield (n = 240) and carcass fabrication data (n = 142) were collected from each treatment at a local processing plant in Siguatepeque, Honduras. Carcass sides were fabricated according to IMPS, fresh beef products, 100 series. All subprimals were collected, with trim sorted according to normal processing standards, and bone weight also collected. All observations were evaluated by PROC GLIMMIX in SAS (version 9.3, SAS Inst. Inc., Cary, NC) to a significance level of (P < 0.05). Diet served as the fixed effect, while kill group was included in the model as a random effect.ResultsThe SBMC treatment was significantly heavier for live weight (LW), hot carcass weight (HCW), cold carcass weight (CCW), and red meat yield (RMY). There was no difference between percent of RMY of CCW (%RMY/CCW, calculated by dividing RMY by CCW) between all treatments. Our GF treatment was least for LW, HCW, CCW, and RMY. Overall offal weights were heaviest (P < 0.01) for SBMC and least for GF (70.19 and 51.84 (kg), respectively). Offal was most valuable for our DDG, SC, SBMC, and SORG treatments (61.95, 63.16, 62.93, and 61.01 (US$), respectively, P < 0.01). Our GF treatment was significantly least for offal value (49.90 (US$), P < 0.01). Additionally, SBMC was heaviest (P < 0.01) for ribeye roll, skirt, clod, knuckle, outside round, inside round, eye of round, pressed trim and ribs. Our GF treatment was lightest (P < 0.01) for ribeye roll, brisket, clod, tenderloin, striploin, top sirloin, knuckle, outside round, inside round, eye of round, shank meat, 80/20 lean, 50/50 trim, ribs, white bone and red bone. Our SBMC treatment was highest for CV (carcass value) (P < 0.01) at 1429.07 (US$), while our GF treatment was lowest for CV at 930.43 (US$). Additionally, our SBMC diet was most profitable to the processor, resulting in a 259.96 (US$) profit, while GF was least profitable at 164.68 (US$; P < 0.01).ConclusionOverall there were (P < 0.01) differences in RMY for all treatments. However, there were no differences in %RMY/CCW (P = 0.17). With increases in energy and protein within the diet, there was a significant increase in weight, therefore an increase in RMY, CCW, and overall CV. Every formulated finishing program was considerably more valuable and higher yielding than GF, and would result in a superior monetary product for the producer, packer, and consumer. The RMY, and consequently CV, was highly influenced by weight. Overall, any treatment compared to GF increased weight, therefore increasing monetary profit for the processor and producer.Figure 1

Bloom Development of the Beef Semimembranosus and Triceps Brachii as Influenced by Wet-Aging

The semimembranosus (SM) and triceps brachii (TB) from USDA Select beef carcasses were used to test the effect of wet-aging period on bloom development. Inside rounds (IMPS#168) and shoulder clods (IMPS #114) were randomly allocated to 0, 7, 14, 21, 28, and 35 d wet-aging at 2°C (n = 10 subprimal cuts/aging period). Each week, two 2.54-cm-thick, non-adjacent steaks were cut from aged inside rounds and shoulder clods, and instrumental color (L*, a*, and b*) of the SM and TB was measured at 10-min intervals for 2 h after cutting. Steaks from the SM and TB became a more vivid (greater C* values; P &lt; 0.05), redder (greater a* values; P &lt; 0.05), and yellower (greater b* values; P &lt; 0.05) color during the 120-min bloom period. Moreover, the calculated proportion of oxymyoglobin (OMb) in SM and TB steaks increased (linear, P &lt; 0.001) during the first 80 min after cutting but stabilized thereafter. Redness (a* and hue angles), b*, and C* values decreased (linear, P ≤ 0.050) in SM steaks as duration of wet-aging increased from 0 to 35 d, but length of wet-aging had no (P ≥ 0.127) effect on instrumental color measures of TB steaks. Neither the percentage of calculated OMb (P = 0.580) nor OMb asymptotic point (P ≥ 0.214) for SM steaks was affected by duration of wet-aging, and, even though the proportion of OMb in TB steaks was not altered (P = 0.459) by postmortem aging, OMb asymptotic points increased (linear, P = 0.001) in TB steaks with increasing durations of wet-aging. Results of these experiments indicate that 90%, or more, of the change in color was achieved within the first 50 to 60 min after cutting, but duration of wet-aging had little to no impact on bloom development in SM and TB steaks.

Effect of vitamin D, zilpaterol hydrochloride supplementation, and postmortem aging on shear force measurements of three muscles in finishing beef steers.

Vitamin D (D3) supplementation may be used to increase tenderness in beef from cattle fed zilpaterol hydrochloride (ZH). The study was arranged as a 2 × 2 factorial with fixed effects of ZH (no ZH or ZH fed at 8.3 mg/kg DM for 20 d with a 3-d withdrawal) and D3 (no D3 or 500,000 IU D3·steer·d for 10 d prior to harvest). Cattle ( = 466) were harvested in 2 blocks on the basis of BW with subsequent collection of carcass data. Full loins and inside rounds ( = 144 of each subprimal) were collected for fabrication of 5 steaks from the longissimus lumborum (LL), gluteus medius (GM), and semimembranosus (SM), which were aged for 7, 14, 21, 28, or 35 d. Warner-Bratzler shear force (WBSF) was used to evaluate mechanical tenderness of LL, GM, and SM steaks at all aging periods. Slice shear force (SSF) analysis was conducted on only 14- and 21-d LL steaks. No interactions ( > 0.05) between ZH and D3 occurred throughout the entire study. Supplementing ZH resulted in increased HCW ( < 0.01), larger LM area ( < 0.01), and improved calculated yield grades ( < 0.01) with decreases in fat thickness ( = 0.02) and marbling scores ( = 0.05). Supplementation with D3 increased calculated yield grade ( < 0.01) and decreased ( = 0.01) rib eye area. Feeding ZH increased ( ≤ 0.05) WBSF of LL steaks at each postmortem age interval, whereas D3 had no effect ( > 0.05) on WBSF or SSF of LL steaks. Like for WBSF, ZH supplementation increased SSF values at 14 and 21 d postmortem ( < 0.01) compared with those for non-ZH steaks. There was an interaction between ZH and postmortem age ( < 0.01) for WBSF of LL steaks. At 7 d LL steaks from ZH steers sheared over 0.6 kg greater than non-ZH steaks; however, by 21 d this difference was reduced to an average of 0.2 kg. Differences in distribution between LL steaks below 3.0 kg from non-ZH and ZH-fed cattle were also notable ( ≤ 0.05) through 21 d of aging. At 35 d postmortem a high proportion of LL steaks (68.5%) from ZH-fed steers required less than 3.0 kg to shear. Supplementation with ZH and D3 had no impact ( > 0.05) on WBSF values of GM steaks. Feeding ZH did not alter WBSF of SM steaks, but at 28 d D3 increased ( = 0.04) WBSF values. Shear force in ZH steaks was not effectively reduced by feeding D3 for 10 d to steers prior to harvest. Aging, however, was an effective method of reducing initially greater shear force values in LL steaks and, to a lesser degree, GM steaks from ZH-fed cattle.

Experimental Study on Seakeeping Performance of a Catamaran with Asymmetric Demi-Hulls

To capture the seakeeping performance of a catamaran with asymmetric demi-hulls, tank tests were carried out in regular head waves using a scaled model with 2.036 m in length. The lateral space between the demi-hulls was changed in the tests as W/B=2.55, 2.90 and 3.25, where W denotes breadth overall and B the breadth of the demi-hull. Also, two models with different water lines of inside flat and outside round (IF-type) and of outside flat and inside round (OF-type) were used. OF-type is superior to IF-type in both ship motion and added resistance performances in waves at the design speed. In IF-type series, the smallest clearance, W/B=2.55 is the best in the added resistance performance.

Use of low dose e-beam irradiation to reduce E. coli O157:H7, non-O157 (VTEC) E. coli and Salmonella viability on meat surfaces

This study determined the extent that irradiation of fresh beef surfaces with an absorbed dose of 1kGy electron (e-) beam irradiation might reduce the viability of mixtures of O157 and non-O157 verotoxigenic Escherichia coli (VTEC) and Salmonella. These were grouped together based on similar resistances to irradiation and inoculated on beef surfaces (outside flat and inside round, top and bottom muscle cuts), and then e-beam irradiated. Salmonella serovars were most resistant to 1kGy treatment, showing a reduction of ≤1.9logCFU/g. This treatment reduced the viability of two groups of non-O157 E. coli mixtures by ≤4.5 and ≤3.9logCFU/g. Log reductions of ≤4.0logCFU/g were observed for E. coli O157:H7 cocktails. Since under normal processing conditions the levels of these pathogens on beef carcasses would be lower than the lethality caused by the treatment used, irradiation at 1kGy would be expected to eliminate the hazard represented by VTEC E. coli.

Effect of Low‐Dose Electron Beam Irradiation on Quality of Ground Beef Patties and Raw, Intact Carcass Muscle Pieces

The objectives of this study were to determine the effects of a low-dose (≤1 kGy), low-penetration electron beam on the sensory qualities of (1) raw muscle pieces of beef and (2) cooked ground beef patties. Outside flat, inside round, brisket and sirloin muscle pieces were used as models to demonstrate the effect of irradiation on raw beef odor and color, as evaluated by a trained panel. Ground beef patties were also evaluated by a trained panel for tenderness, juiciness, beef flavor, and aroma at 10%, 20%, and 30% levels of fat, containing 0% (control), 10%, 20%, 50%, and 100% irradiated meat. With whole muscle pieces, the color of controls appeared more red (P < 0.05) than irradiated muscles, however, both control and treatments showed a gradual deterioration in color over 14 d aerobic storage at 4 °C. Off-aroma intensity of both control and treatments increased with storage time, but by day 14, the treated muscles showed significantly (P < 0.05) less off-aroma than the controls, presumably as a result of a lower microbial load. It was found that a 1 kGy absorbed dose had minimal effects on the sensory properties of intact beef muscle pieces. Irradiation did not have a significant effect (P > 0.05) on any of the sensory attributes of the patties. Low-dose irradiation of beef trim to formulate ground beef appears to be a viable alternative processing approach that does not affect product quality.

Salmonella and Escherichia coli O157:H7 Prevalence in Cattle and on Carcasses in a Vertically Integrated Feedlot and Harvest Plant in Mexico

To determine the prevalence of Salmonella and Escherichia coli O157:H7 in cattle feedlots and the impact of subsequent contamination on carcasses in a Mexican Federal Inspection Type Standards harvest facility, 250 animals were tagged and sampled in each step of the slaughter process. Samples were taken from hides and fecal grabs, and composite samples were taken from three anatomical carcass sites (hindshank, foreshank, and inside round) during the slaughter process, at preevisceration (PE), prior to entering the hot box (PHB), and after 24 h of dry chilling (DC). Additionally, 250 fecal samples were collected from the feedlot (FL), holding pens (HP), and intestinal feces (IF), and water samples were taken from the HP area. E. coli O157:H7 and Salmonella detection were carried out with the BAX System, immunomagnetic separation, and conventional methods. Overall Salmonella prevalence was 52.5%. The highest prevalence (92.4%) was found on hides, followed by feces from the HP (91.0%), FL (55.56%), PE (49.0%), IF (46.8%), and PHB (24.8%), for all sampling periods combined. The lowest prevalence of 6.0% was found after DC. The overall prevalence of E. coli O157:H7 was as follows: 11.7% for hides, 5.2% for IF, 2.7% for FL, 2.0% for HP, 0.8% for PE, 0.4% for PHB, and 0.4% for the cooler. High prevalence of Salmonella in IF and on hides present a significant risk factor for contamination by Salmonella at the different processing steps. These results serve as a warning as to the risks of contamination in meats for these pathogens and the importance of following good manufacturing practices during beef production processes.

Canadian beef tenderness survey: 2001–2011

Juárez, M., Larsen, I. L., Klassen, M. and Aalhus, J. L. 2013. Canadian beef tenderness survey: 2001–2011. Can. J. Anim. Sci. 93: 89–97. A large survey across Canada was developed collecting retail beef samples in 2001 (702 steaks) and 2011 (602 steaks). The samples (strip loin, top sirloin, inside round and cross-rib steaks) were evaluated for instrumental tenderness using standard procedures for sampling, storage, cooking and texture evaluation. New equations were also developed in order to compare the results obtained in these studies with consumer thresholds developed in Canada and the United States of America. In general, retail steaks collected in 2011 weighed less and showed higher fat thickness than those from 2001. Regarding tenderness, a significant improvement was observed, especially for strip loin and top sirloin steaks between 2001 and 2011. Using US threshold categories, the percentage of “tender” samples improved for the strip loin (2001=89%; 2011=99%), top sirloin (2001=70%; 2011=87%), inside round (2001=52%; 2011=61%) and cross-rib (2001=65%; 2011=76%) steaks. Similarly, the percentage of “tough” samples shifted from 5, 8 27 and 13% for the strip loin, top sirloin, inside round and cross-rib steaks in 2001 to 1, 5, 13, and 8%, respectively, in 2011. Similar improvements were observed when using the more descriptive four-category Canadian threshold system. These improvements may be due to changes in the animal population, production systems, carcass processing and distribution/handling prior to display in Canada.

Canadian beef tenderness survey: 2001-2011

Juarez, M., Larsen, I. L., Klassen, M. and Aalhus, J. L. 2013. Canadian beef tenderness survey: 2001-2011. Can. J. Anim. Sci. 93: 89-97. A large survey across Canada was developed collecting retail beef samples in 2001 (702 steaks) and 2011 (602 steaks). The samples (strip loin, top sirloin, inside round and cross-rib steaks) were evaluated for instrumental tenderness using standard procedures for sampling, storage, cooking and texture evaluation. New equations were also developed in order to compare the results obtained in these studies with consumer thresholds developed in Canada and the United States of America. In general, retail steaks collected in 2011 weighed less and showed higher fat thickness than those from 2001. Regarding tenderness, a significant improvement was observed, especially for strip loin and top sirloin steaks between 2001 and 2011. Using US threshold categories, the percentage of “tender” samples improved for the strip loin (2001=89%; 2011=99%), top sirloin (2001=70%; 2011=87%), in...

Experimental Investigation on Heat Transfer and Pressure Drop of CNT-Base Oil Nano-Fluid Flow in Rectangular Channels under Constant Wall Temperature

An experimental investigation has been carried out to study the heat transfer and pressure drop characteristics of MWCNT-Base oil nano-fluid flow inside horizontal rectangular channels under constant wall temperature. The temperature of the tube wall was kept constant at around 95 °C to have isothermal boundary condition. The required data were acquired for laminar fully developed flow inside round and rectangular channels. The effect of different parameters such as mass velocity, aspect ratio of rectangular channels and nano-particles concentration on heat transfer coefficient and pressure drop of the flow is studied. Observations show that the heat transfer performance is improved as the aspect ratio is increased. Also, increasing the aspect ratio will result in the pressure drop increasing. In addition, the heat transfer coefficient as well as pressure drop is increased by using nano-fluid instead of base fluid. Furthermore, the performance evaluation of the two enhanced heat transfer techniques studied in this investigation showed that applying rectangular channels instead of the round tube is a more effective way to enhance the convective heat transfer compared to the second method which is using nano-fluids instead of the base fluid.

Do VCs use inside rounds to dilute founders? Some evidence from Silicon Valley

In the bank-borrower setting, a firm's existing lender may exploit its positional advantage to extract rents from the firm in subsequent financings. Analogously, a startup's existing venture capital investors (VCs) may dilute the founder through a follow-on financing from these same VCs (an “inside” round) at an artificially low valuation. Using a hand-collected dataset of Silicon Valley startup firms, we find little evidence that VCs use inside rounds to dilute founders. Instead, our findings suggest that inside rounds are generally used as “backstop financing” for startups that cannot attract new money, and these rounds are conducted at relatively high valuations (perhaps to reduce litigation risk).

左右非対称なデミハルを有する双胴船の性能に関する実験的研究

To capture the ship performances of a catamaran with asymmetric demi-hulls, tank tests were carried out such as resistance test in still water, measurement test of wave height of wash, seakeeping test in regular head waves and captive test for measuring hydrodynamic forces on maneuvering using a scaled model with 2.036m in length. To investigate the effect of clearance of the demi-hulls on the performances, the clearance was changed in the tests as W/B = 2.55, 2.90 and 3.25, where W denotes the breadth overall and B the breadth of the demi-hull. Also, two ship models with different load water line tendencies were used: one is the inside flat and outside round type (IF-type) and the other the outside flat and inside round type (OF-type). The test results obtained are as follows: Residual resistance coefficient of W/B = 2.90 in IF-type is the smallest at the design speed corresponding to Froude number Fn = 0.44 and that of W/B = 2.55 in OF-type is secondary small. In the maximum wave height of the wash, OF-type is almost 30% smaller than IF-type in any demi-hull clearances. In both performances of heave and pitch motions, and added resistance in head waves, OF-type is superior to IF-type near the design speed. Smaller demi-hull clearance and IF-type are better in course keeping performance. The course keeping and turning performances are suitable in any conditions of the catamaran.

Quantifying the aging response and nutrient composition for muscles of the beef round

The objective of this study was to determine the optimal postmortem aging period and nutrient composition for Beef Value Cuts of the round. Forty USDA Select and 40 Premium USDA Choice beef carcasses were selected from a commercial beef packing plant in Colorado over a 12-wk period. The bottom and inside rounds were collected from both sides of each carcass for further fabrication into the following muscles: adductor, gastrocnemius, gracilis, pectineus, and superficial digital flexor. Each pair of muscles was cut into 7 steaks and randomly assigned to 1 of the following aging periods: 2, 4, 6, 10, 14, 21, and 28 d, and placed in refrigerated storage (2°C, never frozen). Upon completion of the designated aging period, steaks were removed from storage, cooked to a peak internal temperature of 72°C, and evaluated using Warner-Bratzler shear force (WBSF). A 2-way interaction was detected (P < 0.05) between individual muscle and postmortem aging period. The WBSF of all muscles except the superficial digital flexor decreased with increased time of postmortem aging. Quality grade did not affect (P > 0.05) WBSF values for the adductor, gastrocnemius, pectineus, and superficial digital flexor muscles. Exponential decay models were used to predict the change in WBSF from 2 to 28 d postmortem (aging response). The adductor, gastrocnemius, Select gracilis, Premium Choice gracilis, and pectineus required 21, 14, 23, 23, and 25 d, respectively, to complete the majority of the aging response. To determine the nutrient composition of the adductor, gastrocnemius, gracilis, pectineus, semimembranosus, and superficial digital flexor, bottom and inside rounds were collected from 10 USDA Select and 10 Premium USDA Choice carcasses and fabricated into the respective muscles, cut into 2.54-cm cubes, frozen (-20°C), and then homogenized. The adductor, gracilis, pectineus, semimembranosus, and superficial digital flexor were analyzed for DM, moisture, CP, and ash percentages. All muscles were evaluated for total lipid, fatty acid, and cholesterol composition. When quality grades were combined, all muscles fell into the extra lean or lean categories specified by USDA guidelines. Results of this study illustrate the potential for Beef Value Cuts of the round to be sold in food service operations and retail stores with marketing emphasis being placed on the exceptional leanness and acceptable tenderness of these cuts.

Emperipolesis and cell death in NOD2-related Blau Syndrome and Crohn’s disease

Background Blau Syndrome (BS), a rare autoinflammatory disease characterized by non-caseating granulomas, is caused by gain-of-function mutations in NOD2. Crohn’s disease (CD) is associated with intestinal granulomas, and SNPs in NOD2. Emperipolesis, the ‘inside round about wandering’ of lymphocytes within other cells is a typical feature of Rosai-Dorfman disease, and seen occasionally in malignancies. Cell survival and cell death are possible outcomes for both the engulfed and engulfing cells.

Distribution ofTaenia saginatametacestodes: a comparison of routine meat inspection and carcase dissection results in experimentally infected calves

A comparison of techniques for detecting the presence of Cysticercus bovis in bovine carcasses was made by using carcass dissection and routine beef inspection guidelines. In the study, 28 calves were used after they were tested and found to be negative for the presence of anti-C. bovis serum antibodies and were inoculated orally with aliquots containing 6×104 Taenia saginata eggs. One hundred and twenty days after inoculation, the animals were slaughtered and a post mortem evaluation was done following Brazilian Federal Beef Inspection guidelines. This routine meat inspection was able to identify 71.42% of the assessed infected carcasses as being parasitized. This result implies that 28.58% of the infected carcasses would have been released as fit for human consumption since they would have been considered as free of C. bovis infection when using this method for carcass assessment. Only 3.07% of the total 2311 metacestodes present in the carcasses were identified by the conventional procedures of sanitary inspection. The assessment of different parts of the carcasses showed high infestation rates in shoulder clod (14.37%), head (11.21%), neck+chuck roll (8.05%), heart (7.75%) and top (inside) round (7.18%) which, together, were responsible for housing 48.51% of all the cysts found in the 24 beef cuts assessed. These numbers contrasted to the low incidence of cysts found in organs such as tongue (3.12%), diaphragm (1.69%) and esophagus (1.60%) which are usually described as predilection sites for the parasite.

Do VCs Use Inside Rounds to Dilute Founders? Some Evidence from Silicon Valley

In the bank-borrower setting, a firm’s existing lender may exploit its positional advantage to extract rents from the firm in subsequent financings. Analogously, a startup’s existing venture capital investors (VCs) may dilute the founder through a follow-on financing from these same VCs (an “inside” round) at an artificially low valuation. Using a hand-collected dataset of Silicon Valley startup firms, we find little evidence that VCs use inside rounds to dilute founders. Instead, our findings suggest that inside rounds are generally used as “backstop financing” for startups that cannot attract new money, and these rounds are conducted at relatively high valuations (perhaps to reduce litigation risk).

Pressure drop and thermal characteristics of CuO–base oil nanofluid laminar flow in flattened tubes under constant heat flux

An experimental investigation has been carried out to study the heat transfer and pressure drop characteristics of nanofluid flow inside horizontal flattened tubes under constant heat flux. The nanofluid is prepared by dispersion of CuO nanoparticle in base oil and stabilized by means of an ultrasonic device. Nanofluids with different particle weight concentrations of 0.2%, 0.5%, 1% and 2% are used. Copper tubes of 11.5 mm I.D. are flattened into oblong shapes and used as test sections. The nanofluid flowing inside the tube is heated by an electrical heating coil wrapped around it. Required data are acquired for laminar and hydrodynamically fully developed flow inside round and flattened tubes. The effect of different parameters such as flow Reynolds number, flattened tube internal height and nanofluid particle concentration on heat transfer coefficient and pressure drop of the flow is studied. Observations show that the heat transfer performance is improved as the tube profile is flattened. Flattening the tube profile resulted in pressure drop increasing. In addition, the heat transfer coefficient as well as pressure drop is increased by using nanofluid instead of base fluid. Furthermore, the performance evaluation of the two enhanced heat transfer techniques studied in this investigation shows that applying flattened tubes instead of the round tube is a more effective way to enhance the convective heat transfer coefficient compared to the second method which is using nanofluids instead of the base liquid.

Implementation of targeted interventions to control Escherichia coli O157:H7 in a commercial abattoir

The objective of this study was to define locations on the carcass with highest contamination of E. coli O157 throughout the harvest process and implement targeted interventions to reduce or eliminate contamination. To establish a pathogen baseline, samples were collected at the foreshank, hindshank, inside round, neck and midline area and evaluated for E. coli O157:H7 presence. Environmental samples were also collected in the harvest area and the fabrication area of the facility. E. coli O157:H7 prevalence was highest on the foreshank, hindshank and inside rounds in the baseline study and steam vacuums/cones were implemented as an intervention in these specific areas on the harvest floor. At pre-evisceration, foreshank prevalence of E. coli O157:H7 was significantly ( P < 0.05) reduced from 21.7% to 3.1% after the application of steam interventions. At the final rail, foreshank prevalence in the baseline study was 4.2% while no E. coli O157:H7 was detected post-intervention implementation. E. coli O157:H7 on hindshanks and inside rounds was significantly reduced after intervention implementation from 24.2 to 11.5% and 37.5 to 16.7%, respectively at the final rail. Pathogen contamination of environmental samples collected in fabrication declined from 6.7% to 0.7% after slaughter interventions were implemented. Data indicate the identifying areas of contamination on the carcass and implementing interventions can significantly reduce E. coli O157 on the carcasses and in the fabrication environment.

Extended ageing time and temperature effects on quality of sub-primal cuts of boxed beef

Most of the information indicating ageing improves tenderness has been collected on the loin and rib-eye muscles over relatively short ageing times, assuming that all muscles will react similarly. In the present study, the effect of extended ageing times on instrumental texture (56 d) and sensory characteristics (42 d) of six different beef sub-primals [striploin (SL), inside round (IR), outside round (OR), eye of round (ER), blade eye (BE) and chuck tender (CT)] was studied. The effects of two ageing temperatures (1 and 5°C) were also compared. In general, ageing increased tenderness (P &lt; 0.05) of SL, BE, ER and CT sub-primals, although BE shear force increased after 42 d of ageing. On the other hand, ageing had no effect on IR tenderness (P &gt; 0.05) and resulted in a decrease in tenderness of OR (P &lt; 0.05) until day 35, with a later increase after 42 d of ageing. Increasing ageing temperature (5°C) had limited effect on tenderness, but ageing time and temperature increases led to lower flavour and higher off-flavour intensity (P &lt; 0.05) of the studied sub-primals. These results suggest that cut-specific maximum ageing times and rigid adherence to temperature maximums would be of benefit to optimize post-slaughter processes and meat quality.Key words: Beef, ageing, tenderness, muscle