Hot-air drying of hybrid catfish powder at 60-180 degrees Celsius revealed multiple trade-offs. Higher temperatures reduced moisture and microbes but increased oxidation and loss of valuable fatty acids and functional properties. The authors judged 120 degrees the best balance under the tested conditions.
Key findings
- Moisture fell from 6.24% to 4.75% and water activity from 0.42 to 0.23, with microbial counts reduced at 120 degrees or above. Protein concentration rose from 57.63% to 62.24%, while fat fell from 22.49% to 17.17%, DHA from 4.61% to 3.20%, and emulsion stability from 57.14% to 42.10% at 180 degrees.
Why this matters globally
Converting perishable fish into powder may reduce loss, extend distribution, and create a protein ingredient, but processing must preserve fatty acids, flavor, and formulation functionality. The study supports temperature selection by product goal rather than maximum heat.
Thai researcher contribution
Burapha University and Prince of Songkla University collaborated with a Chinese researcher to evaluate an economically important Thai catfish across nutrition, aroma, microbiology, functionality, and structure.
Limitations to consider
Laboratory results do not report drying time, energy yield, cost, consumer testing, or packaged shelf life. Microbial safety requires organism-specific and regulatory criteria, not total counts alone. Higher protein percentage reflects compositional concentration, not creation of protein.