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.