Processing factors that influence casein and serum protein separation by microfiltration.
1Northeast Dairy Foods Research Center, Department of Food Science, Cornell University, Ithaca, NY 14853, USA.
Journal of Dairy Science
|September 22, 2010
Summary
This study models microfiltration of skim milk to optimize casein (CN) and serum protein (SP) separation. Key factors like milk composition and heat treatment significantly impact yields of micellar CN concentrate (MCC) and SP isolate (MSPI).
Area of Science:
- Food Science and Technology
- Dairy Processing
- Separation Science
Background:
- Microfiltration is crucial for separating casein (CN) and serum proteins (SP) in skim milk.
- Optimizing processing parameters is essential for maximizing yields of valuable dairy protein fractions.
- A mathematical model aids in predicting and understanding the complex interactions within microfiltration systems.
Purpose of the Study:
- To model the microfiltration of skim milk to separate casein (CN) from serum proteins (SP).
- To evaluate the impact of five key processing factors on system performance and product yield.
- To predict the yield of micellar CN concentrate (MCC) and milk SP isolate (MSPI).
Main Methods:
- Development of a 4-stage mathematical model for skim milk microfiltration.
- Simulation of five factors: skim milk composition, heat treatment, concentration/diafiltration factors (CF/DF), CF/DF control, and SP membrane rejection.
- Analysis of retentate/permeate composition, SP removal, and MCC/MSPI yields.
Main Results:
- Increased skim milk true protein (TP) concentration enhanced MCC and MSPI yields.
- Higher heat treatment increased apparent CN content but reduced MSPI yield and SP removal.
- Higher CF/DF increased TP concentration and SP removal; CF/DF balance critically affected TP concentration.
Conclusions:
- Skim milk composition and target CF/DF are primary drivers of retentate TP concentration.
- Heat treatment, SP removal factor, and target CF/DF most influence cumulative SP removal.
- Initial skim milk composition dictates MCC yield, while skim milk composition, heat treatment, and SP removal factor affect MSPI yield.
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