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Notes: The extent of moisture migration from the flesh of frozen, raw breaded shrimp was studied for 9 months. The experiments were designed to monitor the effects of moisture migration on the total net weights and the total “percent shrimp material.” The breaded shrimp were (1) blast frozen-stored in the retail freezer (−16°F, −26.6°C), (2) blast frozen-stored in the warehouse freezer (−12±F°2°, −24.4°C), (3) individually quick frozen (IQF)-stored in the retail freezer (−16°F, −26°C), and (4) individually quick frozen stored in the warehouse freezer (−12°F±2°, −24.4°C). As storage time increased the percent breading increased for all treatments. The percent shrimp, the gross weights, the net weights, and the percent moisture decreased as storage time increased. The rate of moisture migration was retarded in the breaded shrimp (i.e. IQF and blast frozen) stored in the warehouse freezer, when compared to the rate of moisture migration in the breaded shrimp (i.e. IQF and blast frozen) stored in the retail freezer.

Notes: Effects of moisture loss in tray-packed fresh fillets of Flounder (Pogonias cromis), Red Snapper (Litjanus blackfordii), Croaker (Micropogon undulatus) and Ocean Perch (Sebastes marinus) were studied. The fish, purchased from seafood suppliers and processed into fillets at their prospective plants, were packaged in plastic foam trays lined with absorbent pads, overwrapped, and subsequently stored at 2°C (35.6°F) for 8 days. Gross and net weights decreased whereas the percent drip increased for all fish during storage. Except for croaker, the total moisture content remained virtually unchanged for all fillets during storage. The acceptability of all fillets decreased as the Trimethylamine-Nitrogen concentrations increased.

Notes: Effects of a calcium alginate coating on retail beef pieces and steaks were studied. Microbiological analyses were performed on beef pieces following treatments with: (1) a calcium alginate coating; (2) a 200 ppm HOCl solution; (3) a combination of 1 and 2; (4) a coliform inoculation and/or (5) no treatment (control). Each sample was wrapped in a polyvinyl chloride (PVC) film and stored at 5°C for up to 7 days. The rate of microbial growth for total and coliform counts on the meat was not significantly different with coated and uncoated meat samples. The HOCl treated meat had significantly lower total microbial counts and coliform populations when compared to either the calcium alginate or the HOCl-calcium alginate treated meat. Acceptance of the calcium alginate film involved retail display and organoleptic evaluations of 40 2.54 cm thick beef steaks. Steaks that received the calcium alginate coating were significantly lower in shrinkage loss, drip and degree of off-odor detected through 96 hr storage when compared to the uncoated steaks. The coating significantly prolonged muscle color through 96 hr storage. No significant differences were observed between treatments for appearance, surface discoloration, flavor, juiciness, tenderness, overall acceptability or cooking loss.

Notes: Abstract Since the Fall of 1992, the University of Central Florida (UCF) and the Orange County Fire Rescue Division (OCFRD) have conducted a joint research program to evaluate the effectiveness of positive pressure ventilation (PPV) as a firefighting technique. The objectives of the research program are to quantitatively measure temperature, air quality, and visibility during actual live fire exercises. Using the data from three residential fires, a novel technique was developed to conduct underwater, scale-model PPV simulations. PPV is a technique that uses fans with high volumetric flow rates to create a slight positive gage pressure within a structure to force heat and combustion products from strategically selected exhaust openings. This rapidly reduces temperatures and retards the combustion process by hindering pyrolysis (the conversion of solid fuel to gaseous, combustible fuel). The removal of smoke improves visibility inside the structure, and the survivability potential for victims is increased by removing toxic gases, lowering temperatures, and introducing fresh air. Results suggest that PPV is an effective technique that can be of significant value when properly applied. Results, specific to this program, that exemplify advantages of PPV include: 1. Reduced temperatures for firefighters and victims. At key firefighting positions, for example, PPV contributed to temperature reductions from 860°F to 140°F within 1 minute. 2. Improved air quality for firefighters. PPV was shown to contribute to oxygen addition and carbon monoxide removal. 3. Faster smoke removal and faster restoration of visibility. When PPV was used, firefighters had water on a residential fire 6 minutes after it began and were walking upright in a cool, highvisibility environment. By contrast, 8 minutes after the start of a second, identical fire in which PPV was not used, firefighters were still crawling around in a hot, smoke-filled environment. 4. Reversal of the direction of flames away from the firefighting location. For example, flashover flames that entered a hallway were pushed back into the burning room soon after the start of PPV. 5. No spread of heat damage. Examination of lateral extent and depth of char on pine 2x4s placed in the path of the flames for PPV and non-PPV fires showed no spreading of heat or flame damage caused by PPV. Full-scale PPV research and training can be expensive. During the course of this project, a technique was developed to conduct scale-model PPV simulation. The simulations are conducted underwater with transparent scale models of residences. The thermodynamics of the fire and the fluid mechanics of PPV are simulated by injecting colored water dyes at rates determined from actual fire measurements. Results from the residential fires colorfully illustrate that the spread of heat and the effects of PPV can be accurately and safely simulated in the laboratory.