Although various studies have evaluated individual factors that influence meat discoloration, limited research has assessed the effects of multiple ground beef cold chain parameters on color. This study evaluated the combined effects of storage temperature, storage time, display temperature, and display time on ground beef color and economic losses due to poor cold chain management. Fresh ground beef chubs (81% lean) were randomly assigned to combinations of 3 storage temperatures (0, 4.5, and 8.9°C), 4 storage times (0, 4, 8, and 12 d), and 3 display temperatures (0, 4.5, and 8.9°C). Visual color was measured every 24 h and a* was measured every 6 h during the 48 h display period. Storage at 0°C minimized discoloration during display compared with storage at 4.5 and 8.9°C. Longer storage times at 0°C did not increase discoloration, whereas prolonged storage at 4.5 and 8.9°C decreased color stability during display. Economic analysis suggested that expected sales loss due to discoloration is positively correlated with storage days, storage temperature, and display temperature. Ground beef stored and displayed at 0°C is shown to minimize expected sales loss with an average loss of $0.29/kg or 2.8% of average retail value. Our results suggest that the total losses to U.S. retailers from cold chain mismanagement are expected to range from $630 million to $1.33 billion when compared with storage and display at 0°C. Simultaneous control of all cold chain parameters is essential for maximizing ground beef color and shelf life

Protein foams are common to foods, such as meringue, whipped cream and mousses. Stability is a challenging issue determined by fat and sugar content. We hypothesize that acetyl-triacylglycerols (acetyl-TAG) that possess sn-3 acetate group with high oleic content can provide stability to the foam at reduced sugar concentrations by increasing the surface viscosity and minimizing serum drainage. A fractional factorial Box-Wilson design was used to investigate the effects of whey protein concentration (WPI) (2-10 wt%), sucrose concentration (SC) (10-30 wt%) and acetyl-TAG concentration (ATC) (0-1 wt%) on overrun (FO), stability against serum drainage (FD) and surface dilatational rheology. Each response was analyzed by linear regression model fitting and a backward elimination algorithm for significance (alpha = 0.01). FO was significantly affected (p < 0.01) by WPI and ATC, but not sucrose concentration. The optimum overrun (nearly 700%) was obtained at 9 wt% WPI and 0.6 wt% ATC. Drainage and viscoelastic properties were significantly (p < 0.01) affected by all process variables. Dynamic complex modulus (|E|) as measured using an optical tensiometer was around 30-40 mN/m when acetyl-TAG was higher than 0.5 wt%. Our findings indicated that the acetyl-TAG can be used to enhance the stability of protein foams in reduced sugar food products, however, not at high sugar concentrations (30 wt%).

BACKGROUND:School nutrition employee behavior plays an important role in preventing foodborne outbreaks and protecting the almost 30 million children who partake in daily school lunch.OBJECTIVE:The study aim was to compare the impact of using a food safety training program with or without using a realistic-event video on handwashing behavior modification for school nutrition employees.DESIGN:A 2-group (control and experimental) pretest with 2 post-tests design was used. The control group received training without the video and the experimental group received the food safety training with a realistic-event video. Measurements used to address the purpose and objectives of this study included questionnaires and direct observations.PARTICIPANTS/SETTING:The sample consisted of 443 school nutrition employees responsible for food preparation and service affiliated with 21 school districts in 18 states. Approximately half of the sample attended the original unmodified training and the other half attended the modified training. Data were collected in the United States during 2017. A total of 338 employees participated in the observations and 443 participants completed the questionnaires during the 3 phases; 935 questionnaires were used for the analysis.INTERVENTION:The intervention involved a food safety training program embedded with a realistic-event video related to handwashing. The video used previous research to target antecedents to handwashing behavior among participants.MAIN OUTCOME MEASURES:Actual behavior was observed across 3 phases-pretraining, post training, and final-for both the control and experimental groups. In addition, indirect and direct measures of behavioral intentions for handwashing were measured.STATISTICAL ANALYSIS PERFORMED:For the observation data, a 2-way, fixed-effects, mixed-model procedure was used to analyze the data. Simple and multiple linear regression and contingency table analyses looking for differences among phases and treatments were used for questionnaire data analysis.RESULTS:Most practices were reported as in compliance (51.3% to 80.6%) for both the control and experimental groups during all phases. The experimental group had a higher behavioral intention of properly washing their hands than participants in the control group.CONCLUSIONS:The results showed that handwashing practices were in compliance most of the time for both the control and experimental groups during all 3 observation periods. Differences among the data collection periods on the theory of planned behavior constructs indicated no statistical effect of the treatment (exposure to the video) between the control and intervention groups.

Foam stability, capacity and viscoelastic properties are essential for foods such as whipped cream and meringue and can be controlled using novel surface-active ingredients. The 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAG) obtained from transgenic Camelina sativa with controlled fatty acid composition and purity at high yield, can serve as a suitable compound to improve foam properties for food applications.Objective: The study is aimed to decrease sucrose content in a model whipped cream formulated by whey protein isolate (WPI) and incorporation of a novel ingredient: acetyl-TAG.Methods:The foam was prepared by mixing WPI, sucrose and acetyl-TAG in deionized water (200 mL) by Box-Wilson design: whey protein isolate (WPI) (2, 4, 6, 8, 10%(w/v)), sucrose (10, 15, 20, 25, 30%(w/w)) and acetyl-TAG (ATC) (0, 0.25, 0.5, 0.75, 1 (w/v)). Foam was whipped using Hamilton Beach 6 speed mixer (Southern Pines, NC, USA) at the highest speed for 20 min with 5 min intervals. SAS software package (Version 9.4 TS Level 1M5) was used for response surface methodology and linear regression model fitting for each response. Foam overrun (FO), serum drainage (FD), dynamic interfacial elasticity (E'), complex modulus (|E|) and viscosity (E’’) were analyzed.Results: Acetyl-TAG was composed of palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), α-linolenic acid (18:3) and eicosapentaenoic acid (EPA) (20:1) as analyzed by thin layer chromatography (TLC) and LC-MS. Foam overrun (max 1100%) was significantly maximized (P< 0.01) by WPI (10% (w/v)) and ATC (0.5% (w/w)), but not sucrose concentration. Viscoelastic properties and stability were significantly (P< 0.01) affected by all process variables. The highest |E| and E' (80 and 75 mN/m, respectively) were recorded with higher acetyl-TAG (above 0.5% w/w).Significance:Novel ingredient, acetyl-TAG, obtained from transgenic camelina seeds can serve as a potential foam stabilizer in reduced-sugar foam formulations, such as whipped cream.

Multiple imputation (MI) has become a feasible method to replace missing data due to the rapid development of computer technology over the past three decades. Nonetheless, a unique issue with MI hinges on the fact that different software packages can give different results. Even when one begins with the same random number seed, conflicting findings can be obtained from the same data under an identical imputation model between SAS (R) and SPSS (R). Consequently, as illustrated in this article, a predictor variable can be claimed both significant and not significant depending on the software being used. Based on the considerations of multiple imputation steps, including result pooling, default selection, and different numbers of imputations, practical suggestions are provided to minimize the discrepancies in the results obtained when using MI. Features of Stata (R) are briefly reviewed in the Discussion section to broaden the comparison of MI computing across widely used software packages.

This paper presents a 13-b C-2C split-array (SA) multiphase switched-capacitor power amplifier (SAMP-SCPA) implemented in 65-nm CMOS. The SAMP-SCPA was designed for 16-b resolution to offer extra states for linearization/calibration using digital pre-distortion (DPD). Resolution limits for SA SCPAs are presented. The SAMP-SCPA allows for the improvement of the SCPA resolution while minimizing the impact on the input power required driving it. A prototype SAMP-SCPA, occupying 0.85 mm x 2 mm, delivers a peak output power of 24 dBm with a peak system efficiency (SE) of 40% at 1.8 GHz. When amplifying a long-term evolution (LTE) signal, the average output power and SE are 18.8 dBm and 21.6%, respectively, with an adjacent channel leakage ration (ACLR) < -30 dBc and error vector magnitude (EVM) of 2.65% rms. The increased resolution allows output power to be traded off for improved linearity and a low power mode demonstrates an EVM as low as 1% rms.

Following the publication of [1], it was pointed out that there were two errors in Table I, related to [2], listed as [38] in the original paper. The work represented in [2] did not use digital predistortion and the matching network consisted of an on-chip transformer (XFMR). The corrected table is presented below as Table I.

This paper presents a 12 bit split-array switched-capacitor power amplifier (SA-SCPA) to improve resolution of an SCPA and hence the linear dynamic range. An attenuation capacitor added between two sub-arrays allows a smaller ratio between the smallest and largest capacitors in the array, accommodating better matching. To compromise between efficiency and linearity, 4 binary bits are chosen for the LSB sub-array and 4 binary + 4 unary bits are chosen for the MSB sub-array. The SA-SCPA is designed and extracted, in a 130nm RF CMOS technology. It delivers a peak output power of 22.6dBm with a peak PAE of 30%. The linearity of the array is simulated using a 64 QAM, OFDM signal with 20 MHz bandwidth and the EVM is 3.8% while meeting the spectral mask.

Enhanced pork loin chops, beef longissimus lumborum steaks, semimembranosus steaks (superficial and deep portions), ground beef, and ground turkey were displayed under light emitting diode (LED) and fluorescent (FLS) lighting in two multi-shelf, retail display cases with identical operating parameters. Visual and instrumental color, internal product temperature, case temperature, case cycling, thiobarbituric acid reactive substances (TBARS), and Enterobacteriaceae and aerobic plate counts were evaluated. Under LED, beef products (except the deep portion of beef semimembranosus steaks) showed less (P<0.05) visual discoloration. Pork loin chops had higher (P<0.05) L* values for LED lighting. Other than beef longissimus lumborum steaks, products displayed under LED lights had colder internal temperatures than products under FLS lights (P<0.05). Under LED, pork loin chops, ground turkey, and beef semimembranosus steaks had higher (P<0.05) values for TBARS. LED provides colder case and product temperatures, more case efficiency, and extended color life by at least 0.5d for longissimus and semimembranosus steaks; however, some LED cuts showed increased lipid oxidation.

TheW. J. Dixon Award for Excellence in Statistical Consulting is given by the American Statistical Association to "a distinguished individual who has demonstrated excellence in statistical consulting or developed and contributed new methods, software, or ways of thinking that improve statistical practice in general." In this article, five of the seven past recipients of this career-capping award share their experiences and perspectives through 10 stepping stones thatmove a practicing statistician fromconsultant to collaborator to leader. We highlight the need formentorship throughout the discussion, and provide direction for statisticianswho would like to incorporate this advice into their careers.

Effects of the β-agonist, ractopamine-HCl (ractopamine), on skeletal muscle protein turnover were evaluated in 16 steers (512 kg) and 16 heifers (473 kg). Treatments were arranged in a 2 × 2 factorial design and included gender (steer vs. heifer) and ractopamine (0 or 200 mg/d). Steers were implanted with 120 mg trenbolone acetate and 24 mg estradiol-17β, heifers with 140 mg trenbolone acetate and 14 mg estradiol-17β. Cattle were fed a diet based on steam-flaked maize. Muscle biopsy samples were collected from m. longissimus and m. biceps femoris on day 0 (prior to ractopamine feeding) and after 14 and 28 d of ractopamine feeding. In vitro protein synthesis rates in m. longissimus tended to be greater for steers than for heifers, but no effect of gender was observed in m. biceps femoris. Gender did not affect in vitro protein degradation rates for either muscle. Ractopamine significantly decreased rates of in vitro protein degradation in m. longissimus, but rates in m. biceps femoris were not affected by ractopamine. Ractopamine did not affect in vitro protein synthesis rates. In general, there were no striking differences between steers and heifers in response to ractopamine, indicating that its effectiveness should be similar between genders. Keywords: Cattle, β-agonist, protein turnover, ractopamine

ABSTRACTEnsuring that new products satisfy specific groups of consumers can impact successful product development. In sensory studies, cluster analysis has been used to segment consumers. Researchers often analyze mean values of products for consumer segments, presuming that the segmented consumers like or dislike similar products. This study investigates how well most/least liked products match for individual members of clusters using various cluster methods in two sensory studies. Four statistical package clustering (SPC) methods were used with hedonic data and data transformed to ranks. Next, the products most frequently rated/ranked highest in each cluster were examined. Four manual clustering groups were extracted and compared with the results of the SPC methods. Standard SPC was not found to separate consumers appropriately to understand their ranking/rating of most/least liked products. For these data, additional manual clustering was necessary to produce consumer cluster segments where the consumers within each group had the same highest/lowest scoring products.PRACTICAL APPLICATIONSStatistical package clustering (SPC) is a common method for determining consumer clusters, but it may not be the best method for separating consumers or for understanding their most or least liked products. The findings from this research show that the assumption that cluster analysis will produce clusters containing consumers who have the same most or least liked products is false. This is important because it shows that clustering consumers using typical SPC may not produce the homogeneous segments that researchers would like to obtain. This can impact further analyses of data for product optimization and preference mapping. SPC with further manual clustering is recommended for more homogeneous segments. In addition, new SPC methods should be developed that generate cluster segments that are more homogeneous.

Crossover designs and within‐subject designs are designs where each experimental unit receives a series of treatments over time. Because treatments are assigned at different time points, one must worry about whether there is carryover or residual effects from a treatment given in a previous period to a subsequent period. This article introduces crossover designs and discusses the statistical analysis of crossover designs. When one has more than two periods and/or more than three treatments, then special designs can be obtained where one can measure a direct comparison between the treatments even if carryover effects exist. Copyright © 2010 John Wiley & Sons, Inc. This article is categorized under: Statistical Models > Linear Models

Crossover designs and within-subject designs are designs where each experimental unit receives a series of treatments over time. Because treatments are assigned at different time points, one must worry about whether there is carryover or residual effects from a treatment given in a previous period to a subsequent period. This article introduces crossover designs and discusses the statistical analysis of crossover designs. When one has more than two periods and/or more than three treatments, then special designs can be obtained where one can measure a direct comparison between the treatments even if carryover effects exist. (C) 2010 John Wiley & Sons, Inc.

We evaluated growth-related responses to ractopamine in steers and heifers. Sixteen Angus steers (512 kg) and 16 Angus heifers (473 kg) housed in individual pens were used in a complete block design. At 90 to 97 d before the experiment, steers were implanted with 120 mg of trenbolone acetate and 24 mg of estradiol-17beta (Component TE-S) and heifers were implanted with 140 mg of trenbolone acetate and 14 mg of estradiol-17beta (Component TE-H). Treatments were arranged as a 2 x 2 factorial and included sex (steer vs. heifer) and ractopamine-HCl (0 or 200 mg/d). Cattle were fed a diet based on steam-flaked corn once daily. Blood and LM and biceps femoris (BF) biopsy samples were collected on d 0 (before ractopamine feeding) and after 14 and 28 d of ractopamine feeding. Serum insulin concentrations were not affected by ractopamine or sex. Serum IGF-I concentrations were greater in steers than heifers (P < 0.001), and steers demonstrated greater IGF-I mRNA expression in BF than heifers (P = 0.05). Ractopamine decreased serum IGF-I concentrations in heifers on d 14, but increased serum IGF-I concentrations in steers on d 28 (sex x ractopamine x day interaction; P = 0.03). Ractopamine did not affect (P >or= 0.19) mRNA expression of IGF-I, IGFBP-3, or calpastatin in BF or LM. However, ractopamine led to increases in LM expression of IGFBP-5 in heifers, but to decreases in expression in steers (ractopamine x sex interaction; P = 0.04). Ractopamine decreased myosin heavy chain IIA mRNA expression in BF (P = 0.04) but not in LM (P = 0.99). Ractopamine decreased beta(2)-receptor mRNA expression in LM of steers on d 14, but not on d 28; in contrast, expression of beta(2)-receptor mRNA in LM of heifers was not affected by ractopamine (sex x ractopamine x day interaction; P = 0.03). Although there were a few criteria for which ractopamine led to differences in response between steers and heifers, there were no striking disparities to suggest that the effectiveness of ractopamine would markedly differ between sexes.

We used four pregnant Holstein cows to delineate ruminal adaptations as cows transitioned from one lactation to the next. Cows were fed typical diets through far-off and close-up dry periods and lactation. We measured ruminal characteristics on day 72 (late lactation), 51 (far-off dry), 23 and 9 (close-up dry) prepartum and on days 6, 20, 34, 48, 62, 76 and 90 postpartum (early lactation). Measurements included: ruminal fill (weight of actual contents), ruminal capacity (volume of rumen when fully filled), digestibilities and ruminal passage rates. Ruminal capacity tended to increase linearly during early lactation but was stable during dry and transition periods. Both total and liquid fill decreased linearly during the dry period, increased across parturition, and increased linearly through early lactation. Dry matter fill decreased as cows were fed the close-up diet at day 23 prepartum then increased near parturition and continued to increase across early lactation. Solid passage rate was greatest when cows were fed the close-up diet, and decreased throughout the transition period. In lactation, solid passage rate responded quadratically with peak at day 48 followed by decreases through day 90 postpartum. Liquid passage increased linearly across the transition period. Total tract organic matter digestibilities increased linearly over the dry period with significant increases prior to or immediately after parturition, then they remained relatively stable over early lactation until they increased at day 90. Fibre digestibilities demonstrated quadratic responses over early lactation, being higher on day 6 and day 90 than at other times. Starch digestibilities decreased linearly across both the dry and transition periods with decreases in lactation until day 62 followed by increases until day 90. High producing lactating dairy cows go through a multitude of ruminal adaptations, in terms of digestion, passage, capacity and fill, as they transition from one lactation to the next.

This experiment investigated the combined effects of two dry-aging methods (unpackaged and in a bag), two loin-cut styles (bone-in shell loins and boneless strip loins), and two aging times (21 and 28days) on the physical, chemical, sensory, and microbial properties of dry-aged beef. Sections from shell and strip loin were assigned randomly to be aged unpackaged or aged packaged in a bag with high moisture permeability. Weight losses increased with aging time. Shell loins lost more (P<0.05) weight during aging compared with strip loins; dry aging in a bag had less (P<0.05) weight loss than unpackaged aging. There were no differences (P>0.05) in any of the sensory traits between shell and strip loins or dry aging using a traditional method or in a bag. Dry aging in a bag creates positive effects on yields, no negative effects on product quality, and adds flexibility and control of the aging environment.