Table 2.

Impact of different homogenization techniques on milk and yogurt properties affecting flavor and texture.

Milk Treatment	Treatment Description	Effect on Milk	Effect on Yogurt
Conventional with Pressure	10–20 MPa	Decrease of MFG size.	Facilitation of curd formation. Whey protein incorporation into the casein matrix. Slight increase in viscosity and firmness.
		Stability of milk as an emulsion.
		Whey proteins absorption to the MFG membrane.
Ultra High Pressure (UHP)	100–1000 MPa	Inactivation of spoilage and pathogenic microorganism.	Higher value of texture characteristics. Higher viscosity. Lower syneresis. Increased water holding capacity.
		Casein micelles disruption.
		Denaturation of several whey proteins.
		MFG size decrease with a tendency for collision and re-aggregation.
High Intensity Ultrasonication	Higher than 20 kHz, amplitude higher than 100 W	MFG size reduction.	Higher value of texture characteristics. Higher viscosity. Lower syneresis. Increased water holding capacity.
		Stability of milk as an emulsion.
		Interaction of whey proteins with casein micelles and MFG.
		Reduction of microbial content.
		Development of off-flavor volatiles.
Microfluidization	Separation of milk into two steams, moving at high velocity with subsequent collision.	MFG size reduction.	Non-fat yogurt: increased syneresis and lower viscosity.
			Low fat yogurt: similar texture characteristics as for conventionally manufactured yogurt.
Pulsed Electric Field (PEF)	Application of electric pulses through milk.	Microbial content reduction.	Similar texture and water holding capacity as for conventionally manufactured yogurt.
	Intensity: 1–50 kV/cm for a few seconds.