Microbial Degradation of Gasoline in Soil: Effect of Season of Sampling

In cases where fire debris contains soil, microorganisms can rapidly and irreversibly alter the chemical composition of any ignitable liquid residue that may be present. In this study, differences in microbial degradation due to the season in which the sample is collected was examined. Soil samples were collected from the same site during Fall, Winter, Spring and Summer and the degradation of gasoline was monitored over 30 days. Predominant viable bacterial populations enumerated using real-time PCR and reverse transcriptase polymerase chain reaction (RT-PCR) enumeration revealed the predominant viable bacterial genera to be Alcaligenes, Bacillus, and Flavobacterium. Overall, the compounds most vulnerable to microbial degradation are the n-alkanes, followed by the mono-substituted alkylbenzenes (e.g., toluene, ethylbenzene, propylbenzene and isopropylbenzene). Benzaldehyde (a degradation product of toluene) was also identified as a marker for the extent of biodegradation. Ultimately, it was determined that soil collected during an unusually hot and dry summer exhibited the least degradation with little to no change in gasoline for up to 4 days, readily detectable n-alkanes for up to 7 days and relatively high levels of resilient compounds such as o-xylene, p-xylene and 1,3,5-trimethylbenzene. These results demonstrate, however, that prompt preservation and/or analysis of soil evidence is required in order to properly classify an ignitable liquid residue

Does Knowing Brand or USDA Grade of Beef Strip Steaks Affect Palatability for Consumers?

In consumers’ eyes, not all beef is considered equal. In addition to USDA quality grades, close to 150 branded beef programs are approved for the segregation and marketing of beef products (USDA, 2015). This large number of product categories allows consumers to have a choice in the products they purchase. Blind sensory panel testing of beef, where consumers are not shown the brand or information about a product, has been used for many years. While important to determine palatability characteristics of beef when evaluated blind, consumers do not select, purchase, and consume beef without additional product information. Evidence suggests that branding and product labeling has an influence on consumers’ decisions before having firsthand experience of the product (Levin and Gaeth, 1988). Branding products allows pieces of information to be used to form quality expectations (Steenkamp and vanTrijp, 1996) and can encourage consumers to pay a premium for the increased quality associated with a brand (Grunert et al., 2004). Moreover, previous research suggests that consumers perceive a product differently when brand information is disclosed (Allison and Uhl, 1964). Numerous studies have evaluated the economic impact of beef branding; however, no research has focused on the effect of branding on consumer perception of beef eating quality. Therefore, our objective was to determine how consumer palatability ratings of beef strip loin steaks are affected when products are identified with a brand or USDA grade

Palatability of Ground Beef Increases When Brand Is Disclosed in Consumer Testing

Of the beef products on the market, ground beef is one of the least expensive and most universal. Ground beef represents the largest volume of protein served in the foodservice industry, at 64%, and is the most popular beef item for consumers when preparing meals in their home (NCBA, 2012). To date, little research has evaluated ground beef palatability despite representing a large sector of the beef market. All ground beef is not the same to consumers. Ground beef from branded beef programs, higher lean points, and primal-specific blends are traditionally sold at retail for higher prices. Branding is used to indicate an increased quality level associated with the product, and encourages consumers to pay a premium in order to receive a superior product (Grunert et al., 2004). Certain branding strategies can influence consumers’ purchasing decisions even if they have not previously tasted the product (Levin and Gaeth, 1988). There is no conclusive evidence of how ground beef palatability changes with fat levels, although some studies have indicated products with higher fat levels are perceived to be more juicy (Myers et al., 2012). It is common for meat product studies to evaluate palatability differences in products through blind testing; however, consumers do not purchase and consume meat without being exposed to information about the product. Therefore, the objective of this study was to determine the effect of brand and product identification on consumer palatability ratings of ground beef patties

Pressed Juice Percentage Can Accurately Sort Beef into Categories of Predicted Juiciness

There are three main factors that contribute to meat palatability: tenderness, juiciness, and flavor (Bratzler, 1971). These three individual factors all play a role in the overall palatability perceived by a consumer. If a product fails for juiciness, there is a greater chance that it will fail in overall acceptability (Emerson et. al, 2013). In the past, research has established a method of segregating steaks based on tenderness acceptability. Researchers have been able to institute thresholds to be able to accurately explain at what shear force a steak will be rated tender by consumers. Similar methods have not been evaluated for juiciness until very recently when Woolley (2014) developed a method to objectively quantify beef juiciness. The method that was created included calculating the percentage of moisture loss from each sample after being compressed. From this work, thresholds for juiciness acceptability were established using loigistic regression; however, additional research is needed to verify these established thresholds. Therefore, the objective of this study was to determine the accuracy of previously established threshold values by testing consumer juiciness ratings for beef steaks in relation to objective juiciness measures

The Effect of Enhancement on Trained Panel Beef Palatability Scores Is Dependent Upon USDA Quality Grade

Quality grades are used to determine beef value. The U.S. Department of Agriculture grading system categorizes beef into levels of eating satisfaction with the highest being Prime and decreases until reaching the Canner quality grade. Currently the premium of Prime graded carcasses over Select is $16.73 (USDA, 2015). Traditionally, USDA Select cuts are known to have lower palatability ratings for juiciness, tenderness, and overall liking. Select steaks also fail to meet consumer eating expectations more than 33% of the time (Corbin, 2015). This failure rate represents a large cost for the industry. Product enhancement utilizing a water, salt, and phosphate solution is commonly used in the pork and poultry industries to increase product eating satisfaction. This technology offers an opportunity for the beef industry to improve palatability as well. Previous research has shown enhancing beef results in a higher juiciness, tenderness, and overall liking ratings by consumers and trained panelists (Pietrasik and Janz, 2009). Previous research has shown enhancing Select cuts results in products that rate similar to Prime (Woolley, 2015). To date, it is unknown if enhancement of higher quality beef (Choice and Prime) results in the same increase in palatability observed in lower quality cuts. Therefore, the objective of this study was to determine the effect of enhancement on trained panel beef palatability scores of strip loins of three quality grades when cooked to three degrees of doneness

How do Alternative Pressures Affect the Accuracy of the Pressed Juice Percentage (PJP) at Predicting Consumer Juiciness Rating?

Texture is the most important sensory trait when evaluating meat products (Gomes et al., 2014). In beef products, tenderness and juiciness interact to form overall texture and mouthfeel. As a result, beef juiciness is one of the most important factors in creating a satisfactory beef eating experience. A recent study by Woolley (2014) developed an instrumental technique for measuring beef juiciness and predicting consumer beef juiciness satisfaction. The method utilizes a texture analyzer to compress cooked beef samples for a period of 8 seconds at 17.6 lb of force and quantifies the percentage of moisture lost as Pressed Juice Percentage (PJP), a predictor of beef juiciness. Results from the initial study found PJP accounts for 20% of the variation in consumer juiciness scores; however, an evaluation of additional pressures is needed to determine if the PJP method can account for an even greater percentage of variation. Thus, the objective of this study was to evaluate the PJP method utilizing three different pressures and determine the relationship of these values to consumer sensory scores for juiciness

Enhancement Increases Consumer Acceptability of Beef Strip Loin Steaks

Juiciness, tenderness, and flavor have been well documented as the primary drivers for beef eating satisfaction and are large contributors to consumer purchasing decisions. Increased marbling, and therefore increased quality grade, in beef products has been the industry tool for predicting eating experience. In order to increase consumer eating satisfaction, the pork industry has implemented widespread use of enhancement technology in fresh pork products to allow products to remain juicy and tender, despite potential overcooking. Using this enhancement technology in the beef industry could allow lower quality beef (USDA Select and lower) to provide better eating experiences for consumers. A recent study by Woolley (2014) found enhancement decreased the percentage of USDA Select steaks rated unacceptable from more than 40% to less than 5%; however, no research exists that determines if enhancement increases palatability independent of marbling score. Therefore, objectives of this study were to evaluate consumer acceptability of enhanced beef strip loin steaks and to determine if enhancement provides an additive effect to marbling for palatability characteristics

MassCode Liquid Arrays as a Tool for Multiplexed High-Throughput Genetic Profiling

Multiplexed detection assays that analyze a modest number of nucleic acid targets over large sample sets are emerging as the preferred testing approach in such applications as routine pathogen typing, outbreak monitoring, and diagnostics. However, very few DNA testing platforms have proven to offer a solution for mid-plexed analysis that is high-throughput, sensitive, and with a low cost per test. In this work, an enhanced genotyping method based on MassCode technology was devised and integrated as part of a high-throughput mid-plexing analytical system that facilitates robust qualitative differential detection of DNA targets. Samples are first analyzed using MassCode PCR (MC-PCR) performed with an array of primer sets encoded with unique mass tags. Lambda exonuclease and an array of MassCode probes are then contacted with MC-PCR products for further interrogation and target sequences are specifically identified. Primer and probe hybridizations occur in homogeneous solution, a clear advantage over micro- or nanoparticle suspension arrays. The two cognate tags coupled to resultant MassCode hybrids are detected in an automated process using a benchtop single quadrupole mass spectrometer. The prospective value of using MassCode probe arrays for multiplexed bioanalysis was demonstrated after developing a 14plex proof of concept assay designed to subtype a select panel of Salmonella enterica serogroups and serovars. This MassCode system is very flexible and test panels can be customized to include more, less, or different markers