C. Z. Alvarado

Comparison of Air and Immersion Chilling on Meat Quality and Shelf Life of Marinated Broiler Breast Fillets

Marinated broiler breast fillets were evaluated using both air- and immersion-chilling treatments. Ninety fillets from air-chilled broiler carcasses and 90 fillets from immersion-chilled broiler carcasses were obtained from a processor to determine differences in meat quality, sensory, and shelf life. At 24 h postmortem, the fillets were vacuum-tumbled (25 in Hg, 30 min, 14 rpm, 4 degrees C) in 2 replications per treatment with a 20% solution (wt/wt) yielding 0.70% NaCl and 0.45% sodium tripolyphosphate in the final product. One-third of the fillets in each replication were packaged in a tray covered with plastic wrap and stored in retail cases to simulate retail shelf-life conditions. The remaining fillets were stored at 4 degrees C for 24 h until analysis for marinade retention, cook loss, consumer evaluation, and objective tenderness. The immersion-chilled fillets had a significantly lower pH (5.56) and were lighter (L* 54.73) when compared with the air-chilled fillets (5.64, L* 50.13, respectively). The air-chilled fillets had a significantly higher marinade pickup (15.51%) than the immersion-chilled (14.07%) fillets. However, there were no significant differences in cook loss percentage in either treatment (approximately 20.03). Shear value was significantly higher in the immersion-chilled fillets (4.14 N), indicating less tender meat than the air-chilled fillets (3.62 N). In the consumer analyses, the air-chilled fillets were significantly different. Of the respondents that noted differences, 19% indicated differences in texture, and 9.67% indicated taste differences. The air-chilled treatment had significantly lower aerobic plate count in postpackaging d 0, 3, and 9. Also, coliforms were significantly lower in the air-chilled treatment through d 6. Therefore, air chilling carcasses may improve color, marination yield, tenderness, and increase the shelf life of retail-packaged broiler breast fillets.

Research developments in pale, soft, and exudative turkey meat in North America

Pale, soft, and exudative (PSE) refers to meat that is pale in color, forms soft gels, and has poor water-holding ability. Most frequently used in reference to pork, this defective meat is being seen with increasing frequency in turkey and broiler processing plants. It has been estimated that this PSE-type meat represents 5 to 40% of meat that is produced in the poultry industry. With the increased production of further-processed products, this PSE problem has become more apparent in the turkey industry. It has been estimated that due to the high incidence, a single turkey processing plant could be losing

Quality and safety of broiler meat in various chilling systems

2 to 4 million per year, resulting in a loss in excess of

Postrigor tumble marination strategies for improving color and water-holding capacity in normal and pale broiler breast fillets

200 million dollars by the turkey industry alone.

Reduction of Salmonella Enteritidis in Shell Eggs Using Directional Microwave Technology

Chilling is a critical step in poultry processing to attain high-quality meat and to meet the USDA-Food Safety and Inspection Service temperature standards. This study was conducted to determine the effects of commercially available chilling systems on quality and safety of broiler meat. A total of 300 carcasses in 2 replications were randomly selected from a commercial processor and subjected to 3 systems: immersion chill (IC), air chill (AC), and combi in-line air chill (CIAC). Incidence of Salmonella and Campylobacter were determined on pre- and postchilled carcasses. Quality of the meat was evaluated by carcass yield, drip loss, cook loss, texture, moisture content, sensory qualities, and color (L*, a*, and b*) of boneless skinless breast fillets and skin-on drums. Shelf life of whole carcasses, breast fillets, and drums was also determined. The IC resulted in the most reduction of Salmonella (39.7%) and Campylobacter (43%) incidence due to the washing effect and presence of chlorine in the chilled water. There was no significant difference in shelf-life when comparing the chilling methods. The IC had the highest (P < 0.05) carcass yield (6.5%), followed by CIAC (+1.98.0%) and then AC (-1.10%). Drip loss, cook loss, and moisture content of breast fillets were not significantly different for all the chilling systems, but higher L* value was observed for breast fillets at 24 h postmortem treated with IC and CIAC. However, IC exhibited the lightest color and AC was darkest in the drum samples. Shear force of breast meat was significantly more tender for AC and CIAC. There were no differences in the sensory qualities of breast fillets and drums among the 3 chilling systems.

Attachment of Salmonella serovars and Listeria monocytogenes to stainless steel and plastic conveyor belts

Pale or pale, soft, and exudative-like meat can be caused by a decline in pH early postmortem while carcass temperatures are still high. This decrease in pH leads to protein denaturation, attributing to the pale color and poor water-holding capacity that is characteristic of this lesser quality meat. Marination with NaCl and phosphates has been shown to improve protein functionality, thereby reducing lost meat yield and improving meat quality. However, there are few studies relating marination with phosphates to improvements in pale meat. Therefore, the purpose of this experiment was to determine if meat quality improvements could be obtained in pale meat via marination with various phosphate and NaCl treatments without altering the quality and stability of normal or pale meat. The treatments used in this study were 1) sodium tripolyphosphate, an industry control; 2) a high pH phosphate (11.9); 3) a sodium tripolyphosphate and high pH mixture; 4) an agglomerated phosphate; and 5) a nonagglomerated phosphate. The marinades used in this study increased the pH, decreased the L* values of the pale fillets, and improved water-holding capacity. There were no significant differences in overall flavor preference for any of the 5 phosphate treatments. There was also no difference in oxidation or shelf-life trends in either the pale or normal fillets marinated with each of the 5 treatments. The results of this study were that marination with phosphates can be used to marinate pale meat without altering flavor, increasing the development of oxidation, or reducing shelf life.

Quality of and mold growth on white enriched bread for military rations following directional microwave treatment.

Microwaves have been shown to cause thermal as well as nonthermal destruction of pathogens such as Salmonella Enteritidis, which is commonly found in shell eggs. The objective of this study was to examine the use of new directional microwave technology to reduce Salmonella Enteritidis without causing any detrimental effects on quality in white and brown eggs. Treatments were control and microwaved white and brown eggs. Applying directional microwave technology resulted in a 2-log reduction of Salmonella Enteritidis in both the high (10(5) cfu/g) and low (10(2) cfu/g) inoculum. At d 0, there were no differences in water activities, albumen pH, and combined pH between treatments; however, there were significant changes in yolk pH. Collectively, these results indicate that applying directional microwave technology can reduce Salmonella Enteritidis in shell eggs without causing any detrimental effects to quality.

Control of Listeria monocytogenes in turkey deli loaves using organic acids as formulation ingredients.

In poultry industry, cross-contamination due to processing equipment and contact surfaces is very common. This study examined the extent of bacterial attachment to 6 different types and design of conveyor belts: stainless steel-single loop, stainless steel-balance weave, polyurethane with mono-polyester fabric, acetal, polypropylene mesh top, and polypropylene. Clean conveyor belts were immersed separately in either a cocktail of Salmonella serovars (Salmonella Typhimurium and Salmonella Enteritidis) or Listeria monocytogenes strains (Scott A, Brie 1, ATCC 6744) for 1 h at room temperature. Soiled conveyor chips were dipped in poultry rinses contaminated with Salmonella or Listeria cocktail and incubated at 10°C for 48 h. The polyurethane with mono-polyester fabric conveyor belt and chip exhibited a higher (P<0.05) mean number of attached Salmonella serovars (clean: 1.6 to 3.6 cfu/cm2; soiled: 0.8 to 2.4 cfu/cm2) and L. monocytogenes (clean: 4.0 to 4.3 cfu/cm2; soiled: 0.3 to 2.1 cfu/cm2) in both clean and soiled conditions. The stainless steel conveyor belt attached a lower (P<0.05) number of Salmonella serovars (clean: 0 to 2.6 cfu/cm2; soiled: 0.4 to 1.3 cfu/cm2) and L. monocytogenes (clean: 0.4 to 2.9 cfu/cm2; soiled: 0 to 0.7 cfu/cm2) than the polymeric materials, indicating weaker adhesion properties. Plastic conveyor belts exhibited stronger bacterial adhesion compared with stainless steel. The result suggests the importance of selecting the design and finishes of conveyor belt materials that are most resistant to bacterial attachment.

Comparison of quality attributes of shell eggs subjected to directional microwave technology

Meals ready-to-eat (MRE) are self-contained and flexible packages used by military personnel while in the field to store food for an extended period of time; however, inclusion of white bread is not a common practice because of short shelf life stability and spoilage. The objective of this study was to determine mold inhibition and quality attributes over a 60-d period after applying directional microwaves. Different bread loaves were used for quality and for microbiological experiments. For microbiological analysis, bread was exposed to 0-, 5-, 6-, 7-, 8-, 9-, and 10-s directional microwave treatments after inoculation with a 3 strain cocktail of common bread mold, stored at 25 degrees C for 60 d, and monitored for mold growth. For quality analysis, bread was exposed to 0- and 10-s treatments, stored at 25 degrees C, and moisture, water activity (a(w)), softness, and sensory analysis were analyzed on 0, 7, 14, 28, 45, and 60 d. There was no quantifiable mold present at day 0 when treated for 10 s (P < 0.05). By day 60, the 10-s treatment had significantly lower counts (< 3 CFU/g) than the remaining treatments. Directional microwave treatment significantly decreased the moisture content of the bread but was not detectable by consumers. There was no difference in a(w) through day 45 but differences were detected at day 60. There were no differences in softness (mm) of the treated and untreated bread through day 60. No differences were detected by sensory analysis. Directional microwaves can be used to extend the shelf life of white enriched bread up 2 mo with minimal mold growth and without detrimental effect to quality.

Reduction of inoculated Salmonella cocktail in ground turkey and turkey breasts using Lactobacillus-based intervention

The growth of Listeria monocytogenes in further-processed meat products has become a major concern and an important food safety issue. The meat and poultry industries have incorporated interventions such as organic acids in marinades to inhibit the growth of L. monocytogenes. In this study, organic acids were utilized in the raw product and as a postcook dip to determine their inhibitory effect on the growth of L. monocytogenes in turkey deli loaves. The turkey deli loaves were processed, cooked, cooled, inoculated with streptomycin-resistant L. monocytogenes, and then dipped. Treatments were potassium lactate (PL) in the raw product with sodium lactate (SL), sodium diacetate (SD) dip, PL with SL/PL/SD dip, SL with SL/SD dip, and SL with SL/PL/SD dip. There was also a positive (inoculated) and negative (noninoculated) control, which was dipped in distilled water. Days 0, 7, 14, 21, 28, 42, and 56 were sampled for L. monocytogenes. There were no differences (P>0.05) among the organic acid treatments in the turkey deli loaves at any time points; therefore, all of the treatments increased the lag phase of L. monocytogenes, extending the shelf-life of the product. However, there was a difference between the treatments and the positive control at d 7, 14, 21, 28, 42, and 56. The growth of L. monocytogenes increased immediately in the positive control, whereas the negative control appeared to have no growth. These organic acids can provide meat processors with a useful method for extending the lag phase of L. monocytogenes in ready-to-eat meat and poultry products.