Table 1. Volume density particle size distribution during storage at 25°C of UHT milk produced at different homogenization pressures

Storage period (wk)	Particle size (μm)	Particle size distribution (%)
		Homogenization pressure (MPa)
		20	25	30
0	<0.5 μm	45.29±0.89	55.12±4.20	67.84±0.15
	0.5–1 μm	32.84±0.23	31.80±2.66	26.25±0.10
	>1 μm	21.87±0.84	13.08±1.60	5.91±0.07
8	<0.5 μm	43.82±2.50	62.23±2.02	72.37±1.50
	0.5–1 μm	32.45±1.20	28.65±1.55	23.67±1.04
	>1 μm	23.74±1.39	9.12±0.54	3.95±0.54
16	<0.5 μm	59.01±3.21	61.10±0.09	78.63±0.81
	0.5–1 μm	27.50±2.96	29.45±2.91	18.96±0.73
	>1 μm	13.49±3.40	9.45±2.99	2.41±0.22
Two-way ANOVA analysis		Significance
Between homogenization pressure (MPa)		20x	25y	30z
Between storage time (wk)		0a	8a	16b
Interactions of storage time×homogenization pressure		-

Data are expressed as mean±SD (n=3). Volume densities of particles greater than 1 μm were subjected to statistical analysis using two-way ANOVA.
Different superscripts indicate significant difference at p<0.05.
UHT, ultra high temperature; ANOVA, analysis of variance.