Parameters for chilling fish using nano-sized ice crystals (NI) made from 3.6% salt water were investigated. Flake ice mixed with salt water (CS) was utilized for comparative purposes. The effect of ice:fish ratio (2:1, 1.5:1, 1:1) on chilling rates and on time, at, or below threshold temperatures (lowest achievable, 0 degrees C, and 4 degrees C) were investigated. Meltwater handling techniques were also investigated: initially drained (INIT), continuously drained (CONT), or non-drained (NODR). Ice:fish ratio did not significantly affect fish chilling time (p>.05). Increasing ice:fish ratio doubled time at or below 0 degrees C (11 24 41 hr) and increased it 1.5-fold for 4 degrees C (23 34 48 hr). Both NI INIT and CONT performed similarly as fish cooled to 0 degrees C. However, lowest internal fish temperature (-.81 degrees C) was achieved and fish were chilled for longer times at or below 0 degrees C and 4 degrees C with NI INIT. Practical applicationsChilling and storage of fish in slurries of ice and seawater are common postharvest handling practices for fishing vessels. Chilling with a slurry ice is advantageous to solid ice because it more effectively interacts with the product surface to absorb heat. Limitations of slurry ice include the tendency of the ice to float to the container surface and form hard ice crusts. The resultant ice crusts have to be physically broken (usually with a shovel) by employees and this action often damages product. The nano-sized ice crystals in the slurry investigated does not create damaging ice crusts. It is also gel-like in texture and therefore less abrasive. Finally, it is created directly from salt water thereby negating the need for fishermen to buy their ice. The smaller ice crystal size, however, may result in more rapid melting and less effective chilling than more traditional slurry ice. The project demonstrated, that despite the small size of the ice crystals, this type of slurry ice is just as effective in chilling fish and keeping fish below temperature thresholds as currently commercially available ice slurries.

Although osmotic minipumps are a reliable method for inducing nicotine dependence in rodents, continuous nicotine administration does not accurately model the intermittent pattern of nicotine intake in cigarette smokers. Our objectives, therefore, were to investigate whether intermittent nicotine delivery via osmotic minipumps could induce dependence in rats, and to compare the magnitude and duration of withdrawal following forced abstinence from intermittent nicotine to that induced by continuous nicotine administration. In order to administer nicotine intermittently, rats were surgically implanted with saline-filled osmotic minipumps attached to polyethylene tubing that contained hourly unit doses of nicotine alternating with mineral oil to mimic “injections”. Three doses of nicotine (1.2, 2.4, and 4.8 mg/kg/day) and saline were administered for 14 days using this method. In order to compare our intermittent delivery method with the more traditional continuous nicotine delivery, a second group of rats was implanted with minipumps attached to tubing that delivered continuous nicotine for 14 days. Rats were administered a 1.5 mg/kg subcutaneous (SC) mecamylamine challenge and observed for somatic signs of withdrawal on days 7, 14, 21, and 28 following minipump implantation. Fifteen somatic withdrawal signs were summed within a 50-minute observation period to obtain a composite Dependence Score. A generalized linear mixed-effects model revealed a significant Day × Dose × Method interaction. Amongst continuously-treated rats, only 4.8 mg/kg/d nicotine resulted in dependence scores significantly greater than those of controls at 14 days of exposure. In contrast, all intermittent nicotine groups showed significantly higher scores beginning at 7 days of exposure and persisting beyond 7 days of abstinence. In general, intermittent delivery produced a more robust withdrawal syndrome than continuous delivery, and did so at a lower dose threshold and with greater persistence after forced abstinence.

Poly(hydroxyalkanoate)s (PHAs) have emerged as a family of aliphatic polyesters produced by a number of bacteria. PHAs have attracted much attention as biodegradable thermoplastics to solve the waste disposal challenge. Currently, from the viewpoint of effective utilization of natural resources, the PHAs are recognized as bio-based polymeric materials produced from renewable biomass resources. In this article, we have attempted to give an overview of research and development on biosynthesis, structure and properties, and biodegradability of PHAs, and to relate prospects of the field. In addition, the present situation regarding industrial production of PHA materials is presented.

High pressure-low temperature (HPLT) processing was investigated to achieve Escherichia coli O157:H7 inactivation in non-intact, whole muscle beef while maintaining acceptable quality characteristics. Beef semitendinosus was internally inoculated with a four strain E. coli O157:H7 cocktail and frozen to 35 degrees C, then subjected to 551 MPa for 4 min (HPLT). Compared to frozen, untreated control (F), HPLT reduced microbial population by 1.7 log colony forming units (CFU)/g on selective media and 1.4 log on non-selective media. High pressure without freezing (551 MPa/4 min/3 degrees C) increased pH and lightness while decreasing redness, cook yield, tenderness, and protein solubility. Aside from a 4% decrease in cook yield, HPLT, had no significant effects on quality parameters. It was demonstrated that HPLT treatment reduces internalized E. coli O157:H7 with minimal effect on quality factors, meaning it may have a potential role in reducing the risk associated with non-intact red meat.Industrial relevance: In the current work, high pressure (551 MPa, 4 min) was applied to beef semitendinosus while it was at subfreezing temperatures (<-30 degrees C). Most studies utilizing this high pressure-low temperature (HPLT) process employ subzero capable thermostatic high pressure equipment, which currently has no commercial equivalent Successful HPLT runs were completed in this study using more conventional temperature control (1-3 degrees C) on pilot scale (20 L) high pressure processing equipment The process yielded E. coli 0157:H7 reductions of 1.4-1.7 log colony forming units (CFU)/g, which, while lower than conventional high pressure processing (HPP), may be sufficient to eliminate O157 populations typical of non-intact, whole muscle beef. Various quality factors, including color, purge losses and cooked tenderness, were unaffected by HPLT, while an equivalent HPP process at nonfreezing temperatures (551 MPa, 3 degrees C) induced color change (loss of redness), increased cook losses and decreased cooked tenderness compared to the control and HPLT beef. Producers of non-intact, whole muscle (blade tenderized or brine injected) meat, especially those that ship and sell frozen products, may look to HPLT processes to improve food safety. (C) 2014 Elsevier Ltd. All rights reserved.

This study aimed to determine the interactions among salt (NaCl), sodium phosphate (SP) and mild high pressure processing (HPP) in brine-injected beef. Beef strip loin segments were injected to 10% over initial weight with solutions containing water and various levels of salt (0, 2 or 4% of solution) and/or SP (0 or 4% of solution). Pieces from the loin sections were exposed to varying pressure levels (0.1, 152 or 303 MPa) and evaluated for selected quality and biochemical characteristics. Use of SP and pressure application increased pH by similar to 0.2 units. L* values were increased by pressure and decreased by SP. Redness (a*) increased at 303 MPa. Purge increases due to pressure were mitigated by SP. Pressure application at 303 MPa reduced total and sarcoplasmic protein solubility by 24 and 32%, respectively. There were no beneficial interactions among salt or SP and HPP. However, results indicate SP may prevent yield loss due to HPP.

This study was conducted using response surface methodology to predict fluid loss from injected beef strip steaks as influenced by levels of salt and sodium phosphates (SP) in the injection brine. Also, a beef-based dehydrated beef protein (DBP) water binding ingredient was evaluated. Paired U.S. select beef strip loins were quartered before being injected with 110% of initial weight with brines containing various concentrations of salt and SP (CON) or salt, SP and 5% DBP. Steaks were sliced, overwrapped and stored in the dark for 4d. Purge values ranged from 0.6% to 4.6% for CON and 0.3% to 2.1% for DBP. Fluid losses when accounting for the fluid lost from injection to slicing were as high as 6.8% for CON brines, but only 2.8% for DBP brines. The equations generated here and the DBP product could help producers achieve acceptable purge while reducing sodium use.

These studies focused on maximizing the nutrition and safety of raw whole muscle beef while minimizing quality and shelf-life alteration. The first study used response surface methodology to predict fluid loss from injected beef strip loins and steaks as influenced by levels of salt and sodium phosphates (SP) in the injection brine. Also, a beef-sourced dehydrated beef protein (DBP) water binding ingredient was evaluated. Paired U.S. select beef strip loins were quartered before being injected to 110% of initial weight with brines containing various concentrations of salt and SP (CON) or salt, SP and 5% DBP. Steaks were sliced, overwrapped and stored in the dark for 4 d. Purge values ranged from 0.6% to 4.6% for CON and 0.3% to 2.1% for DBP. Fluid losses when accounting for the fluid lost from injection to slicing were as high as 6.8% for CON brines, but only 2.8% for DBP brines. The models on fluid loss generated from the study and the DBP product could help processors achieve acceptable purge while reducing sodium use. The second study sought to determine the viability of DBP as a replacement for SP in beef injection brines. U.S. Select strip loins (n=20) were injected to 110% of their initial weight with a brine containing 3.6% salt and 4.5% sodium phosphate (CON) or 3.6% salt and 5% dehydrated beef protein (DBP). DBP loins had less fluid loss after 30 min. Steaks from both treatments lost similar amounts of fluid during storage. Total fluid loss was lower for DBP injected product. Lipid oxidation (TBARS) products were 0.23 – 0.60 mg/Kg higher for DBP steaks, but still within acceptable limits (<1.0 mg/Kg). DBP steaks were slightly less red than CON steaks according to instrumental measurements. Sensory panel evaluation, however, indicated no differences in redness. DBP steaks were less tender according to trained sensory panel. Results indicated the DBP to be effective in increasing brine retention and a suitable alternative to phosphates when used in brines injected into beef strip loins. The third study aimed to determine the interactions between salt (NaCl), sodium phosphate (SP) and mild HPP in brine injected beef, as previous studies on comminuted products have shown the action of hydrostatic pressure to increase the effectiveness of salt and phosphates on protein functionality. Beef strip loin segments were injected to 10% over initial weight with solutions containing water and various levels of salt (0, 2 or 4% of solution) and/or SP (0 or 4% of solution). Pieces from the loin sections were exposed to varying pressure levels (0.1, 152 or 303 MPa) and evaluated for selected quality and biochemical characteristics. Use of SP and pressure application increased pH additively. L* values were increased by pressure and decreased by SP. Redness (a*) increased at 303 MPa. Purge increases due to pressure were mitigated by SP. Pressure application at 303 MPa reduced total and sarcoplasmic protein solubility. This…

A dehydrated beef protein (DBP) was evaluated as a replacement for the phosphate added to beef injection brines. U.S. Select strip loins (n=20) were injected to 110% of their initial weight with a brine containing 3.6% salt and 4.5% sodium phosphate (CON) or 3.6% salt and 5% dehydrated beef protein (DBP). DBP loins had less fluid loss after 30 min. Steaks from both treatments lost similar amounts of fluid during storage. Total fluid loss was lower for DBP injected product. Lipid oxidation (TBARS) products were 0.23-0.60 mg/Kg higher for DBP steaks. DBP steaks were slightly less red than CON steaks according to instrumental measurements. Sensory panel evaluation, however, indicated no differences in redness. DBP steaks were less tender according to trained sensory panel. Results indicated the DBP to be effective in increasing brine retention and a viable alternative to phosphates when used in brines injected into beef strip steaks.

UNLABELLEDBeef patties formulated to contain beef fat, plant oil, and a rosemary extract to increase unsaturated fatty acid content and maintain desirable sensory attributes were compared to control beef patties formulated without plant oils. Treatment patties were formulated to a fat content of 10% or 20% by combining beef trimmings (6% fat) with 4% or 14% addition of a lipid blend. Blends contained 57% beef tallow, 0.3% rosemary extract, and 43% of high oleic safflower oil (SO), olive oil (OO), or corn oil (CO). Lipid oxidation, as measured by TBA values, of treatment patties were similar to control patties after 0 and 3 d of refrigerated (2 °C) storage and up to 56 d of frozen (-10 °C) storage. Cooked lipid blend patties having a fat content of 10% or 20% were similar to or higher than control patties for juiciness and were no different for other sensory attributes evaluated. At fat levels of 10% or 20%, oleic acid (18: 1) in cooked SO patties (46.1% and 50.3%, respectively) and OO patties (43.8% and 48.1%, respectively) was higher than the control (37.3% and 37.6%, respectively). Unsaturated to saturated fatty acid ratios at the 10% or 20% fat levels were higher in SO (1.37 and 1.60, respectively) and CO (1.40 and 1.48, respectively) patties than the control (0.97 and 0.94, respectively). Beef patties manufactured with varying lipid blends increased unsaturated fatty acid content and were similar in physical characteristics and sensory attributes of all beef patties formulated without lipid blends.PRACTICAL APPLICATIONThe development of healthier beef products that will be more appealing to consumers has long been an industry goal. The authors believe that lipid blends such as the one used in this study could be used to create such products, not only in the form of beef patties, but any number of processed meat products. Because the materials and equipment used to create the lipid blends in this study are widely available, their incorporation into meat products would represent a small capital investment. This is an important factor in bringing a reasonably priced, healthier product to consumers.