Table 1.

Typical values of ε′ and ε″ for dry natural polymer films (e.g., low relative humidity below 10%).

Protein Type	Frequency	Temperature	ε′	ε″	Reference
Gelatin	1 MHz	25	12	0.2	[11]
Gluten	1 MHz	15	7	0.08	[40]
Keratin	3 MHz	50	8	0.2	[41]
Zein	1 MHz	25	7	8.10−2	[42]