Optimization of process parameters for supercritical fluid extraction of cholesterol from whole milk powder using ethanol as co-solvent.
BACKGROUND
In spite of being highly nutritious, the consumption of milk is hindered because of its high cholesterol content, which is responsible for numerous cardiac diseases. Supercritical carbon dioxide using ethanol as co-solvent was employed to extract cholesterol from whole milk powder (WMP). This study was undertaken to optimize the process parameters of supercritical fluid extraction (SCFE), viz. extraction temperature, pressure and volume of ethanol.


RESULTS
The cholesterol content of WMP was quantified using high-performance liquid chromatography. The impact of the extraction conditions on the fat content (FC), solubility index (SI) and lightness (L*) of the SCFE-treated WMP were also investigated. The process parameters were optimized using response surface methodology. About 46% reduction in cholesterol was achieved at the optimized conditions of 48 °C, 17 MPa and 31 mL co-solvent; flow rate of expanded CO2, static time and dynamic time of extraction were 6 L min-1, 10 min and 80 min respectively. The treated WMP retained its FC, SI, and L* at moderate limits of 183.67 g kg-1, 96.3% and 96.90, respectively.


CONCLUSIONS
This study demonstrated the feasibility of ethanol-modified SCFE of cholesterol from WMP with negligible changes in its physicochemical properties. © 2016 Society of Chemical Industry.
Agricultural and Food Engineering Department, Indian Institute of Technology Kharagpur, West Bengal, 721302, India. indira27dp@gmail.com.
Indira
I
Dey Paul
Agricultural and Food Engineering Department, Indian Institute of Technology Kharagpur, West Bengal, 721302, India.
Chitra
C
Jayakumar
Agricultural and Food Engineering Department, Indian Institute of Technology Kharagpur, West Bengal, 721302, India.
Hari
H
Niwas Mishra
D000818:Animals; D055598:Chemical Phenomena; D002784:Cholesterol / Q000032:analysis / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D000431:Ethanol; D005223:Fats / Q000032:analysis; D057141:Food, Preserved; D008892:Milk / Q000737:chemistry*; D011312:Pressure; D012995:Solubility; D012997:Solvents; D013696:Temperature
D005223:Fats; D012997:Solvents; D000431:Ethanol; D002784:Cholesterol
cholesterol; high-performance liquid chromatography; response surface methodology; supercritical fluid extraction; whole milk powder