123 research outputs found

    The Spillover Effect of Marketing Discolored Beef on Consumer Preferences for Nondiscolored Beef

    Get PDF
    Consumers prefer bright, cherry-red retail beef. Retailers often mark down the price of discolored beef for quick sale. However, following this practice could result in a net loss of revenue if consumer willingness to pay (WTP) for nondiscolored beef is negatively affected by the presence of discolored beef in the consumer choice set. Through a hypothetical online survey and a controlled in-person experiment, we determine that marketing discolored beef together with nondiscolored beef increases most consumers’ evaluation of, but not their WTP for, nondiscolored beef

    Capturing Temporal Components for Time Series Classification

    Full text link
    Analyzing sequential data is crucial in many domains, particularly due to the abundance of data collected from the Internet of Things paradigm. Time series classification, the task of categorizing sequential data, has gained prominence, with machine learning approaches demonstrating remarkable performance on public benchmark datasets. However, progress has primarily been in designing architectures for learning representations from raw data at fixed (or ideal) time scales, which can fail to generalize to longer sequences. This work introduces a \textit{compositional representation learning} approach trained on statistically coherent components extracted from sequential data. Based on a multi-scale change space, an unsupervised approach is proposed to segment the sequential data into chunks with similar statistical properties. A sequence-based encoder model is trained in a multi-task setting to learn compositional representations from these temporal components for time series classification. We demonstrate its effectiveness through extensive experiments on publicly available time series classification benchmarks. Evaluating the coherence of segmented components shows its competitive performance on the unsupervised segmentation task.Comment: 15 pages, 2 figures, 4 table

    Role of Mitochondria in Beef Color: A Review

    Get PDF
    In postmortem muscle, mitochondria remain active and can influence beef color by oxygen consumption and metmyoglobin reduction. Enzymes involved in glycolysis and the tricarboxylic acid cycle can generate reducing equivalents such as succinate or NADH. Mitochondrial activity is critical to maintain steaks that are bright cherry-red and improve color stability. This review seeks to characterize the role of mitochondria in beef color; more specifically to understand the effects of mitochondrial function on myoglobin redox stability

    Daily quantification of myoglobin forms on beef longissimus lumborum steaks over 7 days of display by near-infrared diffuse reflectance spectroscopy

    Get PDF
    Near-infrared diffuse reflectance spectroscopy (NIR-DRS) was utilized to develop an algorithm using approximately 18 wavelengths spanning 480 to 650 nm to determine oxymyoglobin (OxyMb), deoxymyoglobin (DeoxyMb), and metmyoglobin (MetMb) contents on beef longissimus lumborum muscles. Daily changes in subsurface myoglobin redox forms were evaluated for 7 d using NIR-DRS and compared with the surface color as assessed by a HunterLab MiniScan spectrophotometer as a reference modality. Both measurements revealed that MetMb increased steadily over the duration of display, showing high correlation (R2 = 0.91) between the 2 methods. Comparatively, whereas NIR-DRS revealed OxyMb to have decreased steadily over the period of display, the HunterLab MiniScan spectrophotometer indicated a much later onset of the apparent decrease of OxyMb, resulting in a moderate correlation (R2 = 0.64) between the 2 methods. No correlation was found between the 2 methods regarding the changes of DeoxyMb over the duration of display. The newly developed NIR-DRS algorithm has potential as an alternative method of color assessment in postrigor skeletal muscle.Electrical and Computer EngineeringAnimal and Food Science

    Effects of high-pressure processing on cooked color and eating qualities of dark-cutting beef

    Get PDF
    High meat pH leads to an undercooked or an abnormal pink appearance in fully-cooked product. High-pressure processing (HPP) promotes protein denaturation. The objective was to evaluate the effects of HPP on cooked steak color and sensory attributes of dark-cutting beef. USDA Choice (mean pH = 5.5) and dark-cutting (mean pH = 6.3) strip loin sections were vacuum packaged and treated with 0 (no HPP), 300, 450, and 600 MPa of pressure for 90 s using chilled water. Steaks were randomly assigned to measure external cooked color, Warner- Bratzler shear force, and trained sensory panel. Applying 300 MPa of pressure improved ( P \u3c 0.05) redness of raw dark-cutting steaks compared with control. HPP treatments did not influence ( P \u3e 0.05) a∗ and chroma of the external cooked steak color. HPP treatments also did not affect ( P \u3e 0.05) initial juiciness, sustained juiciness, beef flavor intensity, or overall acceptability. However, 600 MPa made dark-cutting steaks tougher and lighter ( P \u3c 0.05) in appearance than all other treatments. In conclusion, low (300 MPa) and moderate (450 MPa) pressure levels improved raw steak redness without affecting the eating qualities of dark-cutting cooked steaks. HPP did not minimize the undercooked appearance commonly associated with high-pH beef

    Effects of Pork Quality Types, Packaging, and Degree of Doneness on Trained Sensory and Instrumental Tenderness, Color, and Consumer Perception

    Get PDF
    The objective of this study was to evaluate the palatability and retail display differences of 3 types of pork loins. Enhanced (n = 10), nonenhanced (n = 10), and high-quality (n = 10) pork loins were selected from a commercial food distribution company. Loins were cut into 2.54-cm-thick chops and randomly assigned to retail display, sensory, or Warner-Bratzler shear force analyses. For retail display, chops were randomly assigned to 1 of 3 packaging treatments: polyvinyl chloride overwrap, carbon monoxide-modified atmosphere packaging, and high-oxygen modified atmospheric packaging. Instrumental and visual color measurements were taken during 5 d of retail display. For trained sensory panel and Warner-Bratzler shear force analyses, chops were evaluated at 3 different degrees of doneness (63°C, 68°C, and 74°C). Consumer sensory panelists (N = 50) evaluated the overall liking, flavor, juiciness, and tenderness of chops cooked to 68°C. A treatment × packaging interaction (P < 0.05) occurred for L* and a* values. High-quality chops packaged in polyvinyl chloride overwrap were lighter in color (P < 0.05) compared with other treatment and packaging types. However, high- quality chops had lower (P < 0.05) a* values than other treatment and packaging types during retail display. Trained panelists reported no difference (P > 0.05) in tenderness for enhanced chops when cooked at 3 different degrees of doneness. Consumer panelists preferred the enhanced chops for overall liking, tenderness, and juiciness (P < 0.05) compared with high-quality and nonenhanced chops. The results suggest that enhanced, nonenhanced, and high-quality pork loins avail- able in the market vary in color and marbling. Both pork loin type and packaging can influence display color and palatability

    Effects of Rosemary and Green Tea Antioxidants on Ground Beef Patties in Traditional and Modified Atmosphere Packaging

    Get PDF
    The objective of this study was to analyze the effects of rosemary (RSM) and green tea (GT) added to groundbeef to extend shelf life. Four antioxidant treatments were used: control, 2,500 ppm RSM, 300 ppm GT, and 2,500 ppm RSM + 300 ppm GT (RSM + GT). Patties from each treatment (n = 42) were randomly packaged into one of 3 types: polyvinyl chloride (PVC) overwrap, modified atmospheric packaging (MAP), or master packages (MP). Packages of MAP and MP were flushed with 0.4% CO, 69.6% nitrogen (N2), and 30% carbon dioxide (CO2). Patties in PVC and MAP were placed directly into display cases for 7 d, and MP patties were placed in dark storage for 7 d and then in display cases for another 7 d. Instrumental and subjective color, lipid oxidation, and sensory panel scores were measured. In MAP, patties with GT had increased (P < 0.05) a* and chroma values by day 6 of retail display. In MP at 3 d of retail display, GT patties exhibited increased (P < 0.05) L* values (lighter), display color (deeper red), and surface discoloration (greater discoloration) scores compared with RSM + GT patties. However, GT and RSM patties were not different (P > 0.05) for these parameters. Trained sensory panelists did not detect a difference between control and GT patties for the green-hay attribute; however, RSM patties had highly detectable (P < 0.05) green-hay flavor. Panelists were unable to detect any differences (P > 0.05) for rancid or fatty flavors regardless of treatment. Patties in MAP were more color stable than those in PVC after 6 d of retail display. In conclusion, patties in MP with GT showed positive instrumental and objective color measurements, as well as lipid oxidation values after 3 d of display, combined with undetectable flavor, warranting further research

    Repackaging Nitrite-Embedded Dark-Cutting Steak in Aerobic Polyvinyl Chloride Film Decreases Surface Redness

    Get PDF
    The overall goal was to evaluate the effects of repackaging nitrite-embedded dark-cutting steaks in polyvinylchloride (PVC) film on surface color. Dark-cutting beef strip loins (n = 8; pH = 6.39) and USDA Low Choice beef strip loins (USDA Choice, n = 6; pH = 5.56) were selected at a commercial packing plant. Dark-cutting loins were bisected and randomly assigned to nonenhanced dark-cutting and enhanced dark-cutting with glucono delta-lactone and rosemary treatments. USDA Choice and nonenhanced dark-cutting steaks were vacuum packaged (VP) and served as controls, whereas enhanced dark-cutting steaks were packed in nitrite-embedded packaging (NP). Steaks from nonenhanced USDA Choice VP, nonenhanced dark-cutting VP, and enhanced dark-cutting NP loins were randomly assigned to 3, 6, or 9 d of dark storage.Following dark storage, steaks were repackaged in PVC and displayed for 6 d at 2°C. Instrumental color, visual color, and aerobic plate count were evaluated for all steaks. Enhanced dark-cutting steaks in NP increased (P < 0.05) a* values compared with USDA Choice and nonenhanced dark-cutting VP during 24 h of dark storage. Enhanced dark-cutting steaks packaged in NP had greater a* and L* values (P < 0.05) than nonenhanced dark-cutting VP steaks during dark storage. Upon repackaging the enhanced dark-cutting steaks from NP, nitric oxide myoglobin decreased (P < 0.05) during the first 12 h of display. Loss of nitric oxide myoglobin corresponds with a darker red appearance, increased surface discoloration, and decreased a* values.There were no differences (P > 0.05) in aerobic plate count between enhanced dark-cutting NP steaks and nonenhanced dark-cutting VP steaks after repackaging. In conclusion, NP improved surface redness; however, repackaging enhanced dark-cutting from NP steaks in PVC decreased color stability and redness of dark-cutting beef

    Consumer Practices and Risk Factors that Predispose to Premature Browning in Cooked Ground Beef

    Get PDF
    Premature browning is a condition in which cooked ground beef patties turn brown before the USDA recommended temperature of 71°C. This presents a potential food safety concern, as consumers may be eating undercooked meat. Although various intrinsic and extrinsic factors contribute to premature browning, the current knowledge indicates that the myoglobin form present within the interior of patties has a significant influence on cooked color. The objective of the study was to determine the consumer practices of cooking, methods to determine doneness, and type of packaging of their purchased ground beef. The data utilized in this study came from Food Demand Survey (FooDS), which tracks consumer preferences, food expenditures, price expectations, and awareness and concern for a variety of food issues. The sample size of FooDS on-line survey for this study was 1,030. The survey questions consisted of doneness of patties, cooking time, and packaging type of patties. Pictures of different packaging types such as a tray, vacuum package, film wrapped, butcher wrapped paper, frozen patties, and chub were also included. Approximately 67% of respondents indicated that they determine the doneness of ground beef patties by visual observation, 18% identify the doneness by a certain length of time for cooking, and 13.5% use a meat thermometer. Interestingly, 69% of respondents noted that they like a brown interior color of cooked patties. If the patties were prone to premature browning, the chances of consuming undercooked patties are higher. Only 5.7% of people bought patties packaged in a vacuum, while 60% of respondents bought patties packaged in film wrapped or in a tray. Even after 20 yr of attempt by the USDA to educate consumers about safe cooking, the current practices increase the likelihood of premature browning and food safety concerns

    Effects of Aging, Modified Atmospheric Packaging, and Display Time on Metmyoglobin Reducing Activity and Oxygen Consumption of High-pH Beef

    Get PDF
    The objective of current research was to determine the effects of extended aging, modified atmospheric packaging (MAP), and display time on metmyoglobin reducing activity (MRA) and oxygen consumption (OC) of high-pH beef using pH sensitive methodology for MRA and OC. Ten normal-pH (mean pH = 5.6) and 10 high-pH loins (mean pH = 6.4) were vacuum packaged on d 3 postmortem and aged for 0, 21, 42, and 62 d at 2°C. Following aging, 2.0-cm-thick steaks were cut from each of the normal- and high-pH loin sections and packaged in either PVC film, high-oxygen (HiOx-MAP), or carbon monoxide modified atmospheric (CO-MAP) packaging. Surface color, OC, and MRA were measured on d 0 and 6 of the respective aging periods. Steaks in HiOx-MAP and CO-MAP had similar (P > 0.05) L* values, which were greater (P normal-pH meat; thus the MRA and OC methodology was useful in relative comparison of packaged meat color stability differences due to pH
    corecore