No description available.

No description available.

Call number: LD2668 .T4 1964 T24 / Master of Science

No description available.

Over the last decade, food processing has become one of the greatest energy converting stages of the food production supply chain. The interdependency of food, water, and energy leads to a need for more water efficient and energy effective ways to produce food. These studies focus on poultry chilling, primarily comparing the potential options of media that could be used during the poultry chilling sub-process. The conventional poultry chilling approach typically involves the immersion of chicken within chilled water in order to quickly decrease the chicken temperature, thus hindering the growth of bacteria. This research is an initial investigation of ice slurry as an energy and water efficient, pathogen reducing, and financially feasible chiller medium in poultry processing. The financial feasibility and electrical energy demand of using ice slurry were explored in a techno-economic model in HOMER Energy, which is a micro-grid design and optimization software. The thermal cooling capacity of ice slurry and fluidity of the solution allows for generation and storage to occur during low electricity cost hours and an application during high electricity cost hours, thus creating savings in electricity costs associated with poultry chilling. During the poultry chilling experimentation, chickens were spiked with Salmonella as temperature probes measured their core body temperature throughout their immersion within the different media. Greater pathogen reductions, faster cooling times, and less water consumption compared to chilled water promotes ice slurry as an alternate medium in the poultry processing industry.

Photocopy of typescript. / Digitized by Kansas Correctional Industries

The prevalence and mode of persistence of Salmonella on commercial poultry processing equipment was examined in this study. The equipment surfaces of six commercial processing plants were sampled over three-time periods designated as A (after processing), B (after cleaning), and C (after sanitization) and each plant was visited three times. Salmonella prevalence was greater (p<0.0001) at time A than times B and C, while there were no differences (p=0.386) between times B and C. A total of twentyive Salmonella isolates from five distinct serovars were recovered from the processing plants. Further examination of the recovered isolates showed that tolerance to sanitizing agents (chlorine and quaternary ammonium compounds, QAC) and/or biofilm formation was the possible mode of persistence. In addition, all the isolates were resistant to multiple antibiotics in different classes of drugs and more than two genes that are responsible for ⅰ). biofilm formation, ⅱ). resistance to QAC, ⅲ). oxidative stress response, and ⅳ). resistance to antibiotics were detected. Three selected isolates were further characterized based on virulence factors and antimicrobial resistance using whole genome sequencing (WGS) to possibly predict phenotypic characteristics. The WGS data correlates with phenotypic characteristics that were previously observed in the isolates including the ability to produce biofilms and resistance to antibiotics including β-lactams, aminoglycosides, and cephalosporins. WGS predicted the isolates carried resistance genes for antibiotic drug classes that were not observed phenotypically. These include macrolides and fluoroquinolone, which is a concern due to its use in treating foodborne infection. Furthermore, the genome of the three selected isolates were predicted to have over sixty virulence genes that allow Salmonella to invade, attach, and colonize the host cells. The results from this study suggest that the antimicrobials used for sanitization may be insufficient to inactivate Salmonella because of the ability to produce biofilms on processing surfaces. Most importantly, the results suggest the ability of the isolates to cause infection in humans meaning if contamination were to occur, the right antibiotic treatment could be a challenge. Further research is imperative to determine the effective antimicrobial for Salmonella biofilms.

Poultry slaughtering encompasses a series of processing steps with the objective of harvesting the consumable meat. The scalding process consists of the submersion of carcasses in hot water tanks to facilitate the removal of feathers during slaughter. However, the use of a common scalding tank increases the likelihood of carcass cross contamination considering that dirt, fecal material and even digestive and intestinal contents carrying pathogens and other bacteria are widely spread during this operation. Similar cross contamination occurs in the process of chilling carcasses, which also requires submersion of broilers in communal tanks filled with ice and cold water. A plausible approach to reduce contamination in scalders or chillers is the use of Pulsed Electric Fields (PEF) to decontaminate scalder/ chiller water. PEF uses electricity to kill bacteria suspended in liquid media and could be utilized in poultry scalders and chillers to reduce bacterial contamination on carcasses and reduce the potential risk of pathogens reaching the final consumer. A pilot scale system was assembled by the use of a pulse electric field generator (Model SF-700, Simmons. Eng. Co., Dallas, GA) coupled with a commercial scalding tank (Dunkmaster®, Knase Company Inc, MI). C. coli and C. jejuni along with marker strains of Novobiocin and Nalidixic acid resistant S. typhimurium and S. enteritidis strains were used in challenge studies evaluating the effects of the PEF on carcasses, scalder and chiller water contamination. The system was evaluated with 0, 0.5, and 1% sodium chloride in the water with 40 volts of electric current and 0.54 of amperage. Samples were collected at 0, 40, 80, 160, 200 s of treatment with a 10 s on, 5 s off cyclical pulses. The use of PEF in regular scalder/chiller water showed little effect on Salmonella and Campylobacter reductions. However, with the addition of 0.5% NaCl caused a significant (P<0.5) log CFU/ml reduction of Salmonella and Campylobacter within the scalder/chiller water at 40, 80, and 160 seconds respectively.

No description available.

No description available.