Conductive hydro drying as an alternative method for egg white powder production

Abstract

The study aimed to evaluate the conductive hydro drying (CHD) process of egg white. The physical and functional properties of egg white dried in a batch type CHD at three different temperatures (40, 45 and 50 °C) were compared with spray-dried (SD) and freeze-dried (FD) egg white. Various physical and chemical characteristics were analyzed for the egg white powders. Moisture content (3–4%) and water activity (0.22–0.54) were found to be less in CHD powders than other techniques. In the case of powder characteristics, CHD drying showed superior results with good flowability and solubility (78–84%). Degradation of fluorescence intensity was observed in SD egg white. SEM analysis of egg powder showed a flaky structure of CHD samples and spherical and porous structure in SD and FD flakes. CHD method demonstrated better results in gel formation, color value, the hardness of gel, and emulsion properties of the egg. Owing to foam formation and stability, CHD and FD egg white showed positive effects exhibited more excellent stability and foam formation than spray drying. No significant changes were observed in the functional properties of the egg white protein. The CHD process required lesser drying time to dehydrate egg white with added convenience in terms of simplicity dryer design. Overall, the results confirmed that the CHD method is an effective alternative method for drying egg white.

Keywords:

• Egg powder
• conductive hydro drying
• refractance window drying
• powder characteristics
• spray drying
• freeze drying

Disclosure statement

No conflict of interest was reported by the authors.

Additional information

Funding

The first author thanks the Science and Engineering Research Board (SERB), Government of India for providing fellowship under the N-PDF scheme (PDF/2017/001747).