Work Package 1 (WP1)

WP1: Optimized COL processing

Background: It is crucial that a powdered, packaged COL product has a good quality and solubility and also maintains high bioactivity without forming substances that potentially cause adverse health effects (e.g. intense Maillard reactions and lipid oxidation). Processing of milk (i.e. heat-treatment, filtration, spray-drying, and irradiation) is well known to affect milk bioactive factors and product stability. We will verify effects of the newest processing conditions at BD with focus on COL proteins and lipid fractions.

Methods: The optimized bioactive COL product from BD, which is used for the pig and infant studies that start in 2017, will be compared to a conventionally-produced control COL product. The two COL products are produced by BD from the same source of raw colostrum and used for analysis in both WP1 and 2.

The negative control product is produced under conventional processing and pasteurization conditions, which are believed to destroy bioactive components and initiate products from Maillard reactions and lipid oxidation. The optimized bioactive COL product is produced by identical processing conditions to the currently optimized product that is used for pig and infant studies.

A raw and a freeze-dried COL product (also obtained from the same COL batch) may be added as additional positive COL control, assumed to have minimal damage to COL bioactivity. Storage time may be added as an additional variable. Product quality will be assessed by enzyme activity, peptide analyses and protein denaturation assays. We will test if product solubility and dispersibility are improved by drying the product in the presence of soy lecithin.

Using existing milk-analytical capacity in the group, we will also assess the contents of selected heat-sensitive milk bioactive proteins and enzymes by enzymatic and bioassays, coupled with untargeted profiling of proteins by proteomics. Markers for lipid oxidation and Maillard reactions will be measured by high performance liquid chromatography (HPLC).

Expected results: The currently used and optimized product is expected to possess higher levels of bioactive proteins and enzymes, and lower levels of products derived from Maillard reactions and lipid oxidation, relative to COL produced conventionally. The results will help to substantiate the superiority of our specialized COL product for the end users (hospitalized infants).