Impact of Various Dry-Aging Methods on Meat Quality and Palatability Attributes of Beef Loins from Cull Cow

The objective of this study was to determine the effect of various dry-aging methods on meat quality and palatability attributes of cull cow beef loins. Paired bone-in loins (M. longissimus lumborum) from 13 cull cow carcasses (Holstein, 42+ mo) were obtained at 5d postmortem, divided into four equal sections and randomly assigned into 4 aging methods (wet-aging [WA], conventional dry-aging [DA], dry-aging in water permeable bag [DWA], and UV-light dry-aging [UDA]). The beef sections were aged for 28d at 2°C, 65% relative humidity and 0.8 m/s airflow. Following aging, surface crusts and bones were removed and loin samples were collected for the meat quality, microbiological and sensory analyses.Results indicated that all dry-aged loins had greater moistureand trimming loss compared to WA (P<0.05), while DWA had lower loss than DA and UDA (P<0.05). No differences in shear force, cook loss and both lipid and protein oxidation across all treatments were observed (P>0.05). Among all treatments, DWA exhibited the least color stability indicated by rapid discoloration observed in the sample, while UDA had color attributes comparable to WA throughout the whole display. Microbial analysis indicated that UDA had lower microbial concentration on the surface than the other samples (P<0.05). The consumer panel analysis found that all loins were acceptable and the trained panel analysis indicated that DA loins had lower sour and fatty flavor attributes compared to WA (P<0.05). The results indicate that dry-aging can potentially be utilized as the effective natural process to improve cull cow beef palatability without compromising other meat quality attributes or microbiological shelf-life.

Evaluating optimal purchasing and selling decisions of beef cattle replacement females

PurposeThe objective of this research was to determine the optimal age and pregnancy status for buying and selling replacement of beef females for risk-neutral and risk-averse producers.Design/methodology/approachA hedonic pricing model was estimated to measure how age, pregnancy status, breed and cull cow prices impact the sale price of these cattle. Data came from an annual heifer and cow sale in Tennessee between 2009 and 2018. A financial simulation model was developed to generate distributions of net present value (NPV) for buying replacement females at various ages and pregnancy status and then selling that female at various ages and pregnancy status.FindingsThe hedonic pricing model indicates sale prices were highest for five-year-old cows that were between four to five months pregnant. NPV was higher for buying heifers versus buying cows and for buying an open female versus a pregnant female. Regardless of age and pregnancy status when purchased, NPV was higher when the female was sold as pregnant prior to the end of her productive life. The risk analysis showed that risk aversion, buying older open cows and selling them as pregnant earlier in their productive life was preferredOriginality/valueThis research offers unique insight into how pregnancy status and age at sale impacts the animal's NPV while considering risk. These results have implications for educating producers on purchasing and selling decisions of heifers and cows as well as for lenders who finance these purchases.

Impacts of Various Dry-Aging Methods on Meat Quality and Palatability Attributes of Beef Loins from Cull Cow

ObjectivesBeef from cull cows has been traditionally perceived as low-quality/value meat due to its inferior flavor and tenderness. Given the negative consumer perception of highly processed fresh meat, there is a need to develop a natural post-harvest aging system to improve eating quality attributes of beef products, particularly from cull cows. Dry aging has been practiced for decades as a traditional and natural butchery process, which is also known to improve palatability characteristics. Thus, the main objective of this study was to evaluate the impact of different dry-aging methods on meat quality, microbiological properties and palatability attributes of loins from cull cow beef.Materials and MethodsPaired beef loins from 13 carcasses (Holstein, 30+ mo) were obtained at 5d postmortem, divided into 4 equal length sections and randomly assigned to four aging methods: wet-aging (WA), dry-aging (DA), dry-aging in water permeable bag (DWA) and UV-light dry-aging (UDA; 2 treatment/day, 5 J/s/treatment). Sections were aged for 28d at 2°C, 65% RH and 0.8 m/s air flow. After aging, dry-aged sections (DA, DWA and UDA) were trimmed of dehydrated surface, and trim loss and total saleable yield were recorded. The pH, proximate composition, shear force, water-holding capacity, initial color (instrumental and trained panelist), lipid oxidation (2-thiobabituric acid reactive substances, TBARS), microbial properties (aerobic plate count (APC), lactic acid bacteria (LAB), and yeast and mold (YM) counts) and trained sensory evaluation (11 panelists) were determined. Experimental design was a balanced complete block design. All data were analyzed using PROC MIXED procedure of SAS, and least squares means for all traits were separated (P < 0.05).ResultsDA and UDA had a substantial moisture loss during the aging process, accompanied with higher trim loss compared to other methods (P < 0.05). This resulted in DA having the lowest yield followed by UDA, DWA and WA with the highest saleable yield (P < 0.05). No significant differences were observed on cook loss, WBSF and TBARS between the treatments. DWA had the lowest pH out of all treatments (P < 0.05). UDA had the lowest moisture content and highest drip loss (P < 0.05). Color measurement showed that both DA and WA had significantly higher L* and lower b* values compared to UDA and DWA (P < 0.05). However, a* and lean surface color were not significantly different between the treatments (P > 0.05). For the trim, UDA had the lowest microbial growth among all treatments (P < 0.05). For the lean, UDA had the lowest count for LAB (P < 0.05), WA had the lowest in YM (P < 0.05) and no difference was found for APC between treatments (P > 0.05). Trained sensory panelist found that UDA and WA had higher fat and sour flavor (P < 0.05), and a trend (P = 0.07) of higher oxidized flavor when compared to DWA and DA.ConclusionThe results showed that dry-aging would result in no adverse impact on shear force, cooking loss, initial color and lipid oxidation of mature beef loins. Further, sour and oxidized flavor was lower in dry-aged beef, indicating its potential as value adding process. UV light application minimized microbial growth during dry-aging process, although more analyses are needed to understand its full impact on dry-aged meat quality. Further studies on determining the consumer acceptability as well as flavor-related compound analyses are currently under investigation.

109 Mature cow size and impacts on cow efficiency

According to genetic trend data, mature BW in beef cows continues to increase although the pace is slowing. This change is not increased frame size as the genetic trend for mature height in Angus cattle has been flat since about 1995. In sell-at-weaning enterprises, calf value at weaning must accompany increased cow size to justify the added expense of larger cows. We used the California Net Energy System and NASEM (2016) equations to estimate the annual cost to maintain beef cows varying in mature size. Maintenance energy requirements were assumed to be 77 kcal per kg of metabolic body weight plus 20% during lactation. Reproductive efficiency and average daily milk production was assumed to be equal among the two mature cow BW scenarios. In ranching operations with average mature cow BW of 556 kg and annual feed and grazing costs of $400, $500, $600 or $700, increasing average mature BW by 90.8 kg resulted in increased projected annual feed and grazing cost of $41.05, $51.32, $61.58 and $71.84 per cow, respectively, or about 10%. Estimated differences in variable costs (labor, depreciation, etc.) were minor for the larger cow herd. Assuming an annual replacement rate of 16% and cull cow price of $1.32 per kg, cull cow income would increase by approximately $19.20 per cow per year in the larger cow scenario. Consequently, to break even with the 556 kg mature cow BW scenario, sell-at-weaning enterprises with average mature cow BW of 647 kg must achieve $21.85, $32.12, $42.38, or $52.64 increased calf value depending on average annual cow cost. These estimates of increased income required to offset increased mature cow BW are conservative because no cost was assigned to grow the additional 90.8 kg of cow BW.

Tenderness and sensory attributes of 11 muscles from carcasses within the Canadian cull cow grades

The eating quality and shear force of meat from mature beef carcasses graded within the Canadian grading system were compared with youthful carcasses. Eleven muscles were obtained from mature-graded carcasses with >50% ossification (D1, D2, D3, and D4; n = 84) and youthful carcasses with <50% ossification [over 30 mo (OTM); n = 18, and under 30 mo (UTM) of age; n = 18, based on dentition]; muscles were aged 14 d prior to sensory and shear force analysis. Many muscles from mature-graded carcasses were juicier than UTM, however, most were less tender (P < 0.05). Psoas major was tender, particularly in D1 and OTM carcasses where tenderness measures were not significantly different from UTM (P > 0.05). Shear force values from the infraspinatus of D1 and OTM carcasses were not different from UTM. Flavour intensity was higher in several muscles from D1, D2, and D4 carcasses (P < 0.05), whereas flavour intensity was lower in several muscles from D3 (P < 0.05). Changes to eating quality attributes differed among mature grades; therefore, processors could potentially use the information presented here as a guide for utilizing cuts which retain high eating quality and separating those requiring tenderness intervention to reach consumer acceptability.