C.H. White

Extending shelf life of refrigerated catfish fillets using sodium acetate and monopotassium phosphate

The effects of sodium acetate (SA) and monopotassium phosphate (MKP) on total aerobic plate counts (APC), pH, odor, and appearance of catfish fillets during storage at 4°C were determined. Use of 0.75% and 1.0% SA lowered (P < 0.05) initial APC by 0.6 to 0.7 log units compared to the control. Microbial counts of SA-treated fillets remained lower than the control during storage, resulting in a 6-day shelf-life increase. MKP alone had no effect on APC values, but it did influence the activity of SA. The results indicate that a combination of SA and MKP could prolong the microbiological shelf life of catfish to 12 days at 4°C. Fillets treated with 1% SA alone or SA-MKP combinations had pH values and odor scores that were similar to fresh controls for up to 9 days; however, appearance scores were lower after 3 days, probably due to a brownish and watery appearance. MKP alone is not recommended for shelf-life extension of catfish fillets. Conversely, SA alone or combined with MKP is recommended to extend the microbiological shelf life of refrigerated catfish fillets.

The effect of pasteurization temperature on consumer acceptability, sensory characteristics, volatile compound composition, and shelf-life of fluid milk.

The relationship among consumer acceptability, descriptive sensory attributes, and shelf-life was determined for 2% milk pasteurized at 77, 79, 82, and 85 degrees C. Sensory descriptive attributes and volatile compound composition were monitored over the shelf-life of the products to determine if treatments could be differentiated at various times through out the shelf-life of the product. Consumers preferred 79 degrees C milk over other treatments on d 0; however, at d 6 postpasteurization, 79 and 82 degrees C milks were preferred over the 77 degrees C treatment. Consumers were grouped into 8 clusters based on product liking for both d 0 and d 6 evaluations. The largest cluster liked all pasteurization treatments, and 79 degrees C milk was highly acceptable to all consumers who liked milk. Similar sensory descriptors indicated the end of shelf-life for all pasteurization treatments even though treatments could be differentiated by descriptors on d 0. This research reveals that altering the pasteurization temperature from 79 degrees C may cause a decrease in consumer acceptability to some consumers. Also, altering pasteurization temperature did not affect shelf-life or sensory descriptors and volatile compound composition at the end of shelf-life.