Pilot-Scale Interesterification of Special Fat Blends to Prepare Zero-Trans Margarine: Monitoring the Content and Physicochemical Properties of Fatty Acids

The chemical interesterification (CIE) process is a promising approach to modifying and improving oils and the fat structure. In this study, the CIE of the fully hydrogenated soybean oil (FHSO) and sunflower oil (SFO) was performed. Different initial blends with various mass ratios of 20-45 % of FHSO (coded as S1, S2, S3, and S4) were converted to interesterified samples (Si-1, Si-2, Si-3, and Si-4, peer-to-peer). The interesterified samples (60 % content) were used in different margarine formulas with 40 % of palmolein PO (M1, M2, M3, M4), and the margarine enriched with beta-carotene, to compensate for the reduction of carotene during the oil decolorization process during refining. Esterification caused a significant decrease in the solid fat content (SFC) in the initial fat blends and the fatty acid profile analysis confirmed that the content of trans fatty acid was just less than 0.17-0.3 % (According to the definition of zero trans being less than 0.5 g/12 g per serving). The differential scanning calorimetry (DSC) measurement indicated that the interesterified samples possess lower melting points while showing binary or ternary crystallization peaks. The Polarized light microscopy (PLM) confirmed the presence of fine, desirable β´spherulite crystals, which are effective in creating the proper texture in margarine. Different types of formulated margarine were evaluated and compared with one type of the commercial margarine (as a control sample). According to the texture profile analysis (TPA) and organoleptic results, the M3 formula was chosen as the best formulation for margarine preparation (using Si-3 blending with the 35: 65 ratios of FHSO to SFO).