Use of Yarrowia lipolytica Lipase Immobilized in Cell Debris for the Production of Lipolyzed Milk Fat (LMF)

Lipase immobilized on Yarrowia lipolytica cell debris after sonication of yeast cells (LipImDebri) was used in hydrolysis reaction as a novel strategy to produce lipolyzed milk fat (LMF). Extracellular (4732.1 U/L), intracellular (130.0 U/g), and cell debris (181.0 U/g) lipases were obtained in a 4 L bioreactor using residual frying oil as inducer in 24 h fermentation process. LipImDebri showed a good operational stability retaining 70% of lipolytic activity after the second cycle and 40% after the fourth. The highest degree of hydrolysis (28%) was obtained with 500 mg LipImDebri for 6 h of lipolysis of anhydrous milk fat. LMF produced with LipImDebri presented high contents of oleic (35.2%), palmitic (25.0%), and stearic (15.4%) acids and considerable amounts of odor-active short and medium chain fatty acids (C:4-C:10) (8.13%).