Project Number: 1935-41000-091-00
Project Type: Appropriated

Start Date: Aug 16, 2010
End Date: Aug 15, 2015

Objective:
1: Characterize biologically active compounds (BACs) in milk from organic, grass-fed, and conventional herds. 1.a: Identify and quantify the protein-based, lipid-based, and other BACs in milk from organic, grass-fed, and conventional bovine dairy herds, select the BACs that will be tracked for the rest of the study and establish assay methodologies. 1.b: Establish the seasonal variations in the concentrations of the selected protein-based, lipid-based, and other BACs in milk from organic, grass-fed, and conventional bovine dairy herds. 2: Develop technologies to modify the level and stability of selected biological active compounds (BACs) in milk and cheese. 2.a: Determine effects of common milk processing procedures and storage conditions on the concentration and stability of the selected BACs in milk. 2.b: Determine the effects of cheese manufacturing techniques and aging on the concentration and stability of selected BACs in cheese and correlate to changes in quality traits. 2.c: Develop low-salt high-moisture model cheese to determine effects of low-salt environment on the concentration and stability of BACs during aging and correlate to changes in quality traits.

Approach:
This research will focus on measuring the quantity and quality of biologically active components, or BACs, in milk and cheese, and identifying processing factors that affect their stabilities in dairy foods. The BACs of interest contribute to the nutritional, functional, and sensorial quality traits of the products, and may have potential health benefits. A variety of state-of-the-art techniques will be used to measure the BACs (protein/peptides, lipids, minerals, vitamins, and flavor compounds), as well as the physical and microbiological properties of the milk and the functional and textural properties of the cheese. One phase of the project will characterize the naturally occurring BACs in milk and identify sources of milk with high levels of BACs; in particular, milk from multiple organic and conventional farms in mid and eastern Pennsylvania will be evaluated for BACs to determine quality and seasonal variations. Another phase will develop technologies to modify the levels and stability of selected BACs in milk and cheese. Milk will be obtained from organic and conventional farms and processed at the DFFRU milk processing pilot plant with portions being used to manufacture high-moisture cheese (Queso Blanco). The effects of common dairy industry milk processing procedures and storage conditions on the concentration and stability of selected BACs will be evaluated. In another phase of the project, low-sodium high-moisture cheese model will be created to evaluate the effect of the low-sodium environment on the stability of the BACs and the quality traits of the cheese.