Effect of Iron Saturation on the Recovery of Lactoferrin in Rennet Whey Coming from Heat-Treated Skim Milk

Effect of thermal treatments on the percentage of lactoferrin (LF) recovered (% [LF]_w/[LF]_o) in the rennet whey of skim milk heated at different temperatures (10min) and analyzed by reverse-phase HPLC. Errror bars represent the standard deviation of triplicate independent samples. [LF]_w represents the LF concentration in the heated whey fraction and [LF]_o represents the initial LF concentration in the unheated whey (reference).

Effect of iron saturation on the percentage of lactoferrin (LF) recovered (% [LF]_w/[LF]_o) in the rennet whey fraction from thermally treated (10min) skim milk enriched (0.25% protein, wt/vol) with holo-LF (black bars), LF (gray bars), and apo-LF (white bars), and analyzed by reverse-phase HPLC. Errror bars represent the standard deviation of triplicate independent samples. [LF]_w represents the LF concentration in the heated whey fraction and [LF]_o represents the initial LF concentration in the unheated whey (reference).

Effect of LF iron saturation on the percentage of β-LG (A) and α-LA (B) recovered in the rennet whey fraction from thermally treated (10min) skim milk (dark gray bars) and milk spiked (0.25% protein, wt/vol) with holo-LF (black bars), native LF (gray bars), and apo-LF (white bars), and analyzed by reverse-phase HPLC. Errror bars represent the standard deviation of triplicate independent samples.

Nonreduced (NR) and reduced (R) SDS-PAGE of rennet curd from (A) skim milk and (B) milk spiked with LF (0.25% protein, wt/vol) unheated and heated at 60, 70, and 80°C (10min). C = unheated control; LMW = low molecular weight; HMW = high molecular weight; LF = lactoferrin; Std = standard.

Two-dimensional SDS-PAGE patterns: nonreduced (NR) SDS-PAGE in the first dimension (horizontally): and reduced (R) SDS-PAGE in the second dimension (vertically) of (A) rennet curd obtained from unheated skim milk, and (B) heated skim milk (70°C, 10min). 1D = one-dimensional; LMW = low molecular weight; HMW = high molecular weight; LF = lactoferrin.

Two-dimensional SDS-PAGE patterns; nonreduced (NR) SDS-PAGE in the first dimension (horizontally): and reduced (R) SDS-PAGE in the second dimension (vertically) of rennet curd obtained from heated skim milk (70°C, 10min) spiked with LF (0.25% protein, wt/vol). 1D = one-dimensional; LMW = low molecular weight; HMW = high molecular weight; LF = lactoferrin.