Optimization of a soft degumming process of crude rapeseed oil—Changes in its antioxidant capacity

• Published in: Food and bioproducts processing Vol. 105; pp. 26 - 35
• Main Authors: Szydłowska-Czerniak, Aleksandra, Łaszewska, Anna
• Format: Journal Article
• Language: English
• Published: Rugby Elsevier B.V 01.09.2017; Elsevier Science Ltd
• Subjects: Antioxidant capacity; Antioxidants; Box–Behnken design; Brassica napus; Capacity; Crude oil; Degumming; Optimization; Phenolic compounds; Phenols; Phospholipids; Rape plants; Rapeseed; Rapeseed oil; Response surface methodology; Sinapic acid; Sodium; Sodium dodecyl sulfate; Sodium lauryl sulfate; Soft degumming; Stability; Sulfates; Sulfonic acid; Vitamin E; Volume transport; Rapeseed oil; Soft degumming; Antioxidant capacity; Phospholipids; Box–Behnken design; Response surface methodology
• ISSN: 0960-3085; 1744-3571
• DOI: 10.1016/j.fbp.2017.05.012

[Display omitted] •A modified soft degumming was proposed as the first step of oil refining process.•Efficient removal of undesirable phospholipids from the crude oil was achieved.•Soft degumming protects antioxidants in comparison with industrial degumming.•Soft degumming conditions were optimized by response surface methodology.•Chemical agents, water volume, and time affected the efficiency of soft degumming. A modified soft degumming process of crude rapeseed oil for maximizing phospholipid removal and minimizing losses of antioxidants was proposed and optimized by response surface methodology. The effects of water volume, degumming time, and concentration ratio of sodium dodecyl sulfate to disodium ethylenediaminetetraacetate on the concentration of phospholipids and phenolics and antioxidant capacity of oils were evaluated. The soft degumming process removed phospholipids from the crude oil (94.9–98.7%) more effectively than industrial acid degumming (95.3%). Moreover, rapeseed oils revealed high phenolic content (20.0–22.1mg sinapic acid (SA)/100g) and antioxidant capacity, as determined by ferric-reducing antioxidant power (FRAP=301–328μmol Trolox equivalent (TE)/100g), 2,2-diphenyl-1-picrylhydrazyl (DPPH=528–739μmol TE/100g), and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS=1300–1505μmol TE/100g) methods. The predicted optimum water volume (11.5mL), time (19.7min), and concentration ratio of sodium dodecyl sulfate to disodium ethylenediaminetetraacetate (=1) resulted in total phospholipids=67mg/kg, phenolics=20.8mg SA/100g, FRAP=313μmol TE/100g, DPPH=617μmol TE/100g, and ABTS=1346μmol TE/100g. Replacement of industrial acid degumming by the proposed soft degumming can improve the stability of rapeseed oil with potent antioxidant capacity.