Continuous enzymatic interesterification of milkfat with soybean oil produces a highly spreadable product rich in polyunsaturated fatty acids

Abstract

The aim of this study was to tune the physical properties of milkfat by enzymatic interesterification with soybean oil in a continuous fluidized bed reactor (FBR) to obtain healthy interesterified fat blends having suitable texture properties for the food industry. The immobilized commercial non-regioselective Candida antarctica lipase (Novozym 1 435) and sn1,3-regioselective Rhizopus oryzae lipase, immobilized in an organicinorganic hybrid matrix of polysiloxane-polyvinyl alcohol, were used as biocatalysts in a FBR. The minimum value of the ascendant flow of the medium for allowing fluidization in the system was 3.13 mLÁmin À1 . The reaction was evaluated in terms of the interesterification yield (IY), consistency values and solid fat content (SFC). The IY values of 10.50 AE 1.64% and of 5.70 AE 1.46% were attained for Novozym 1 435 and for immobilized R. oryzae lipase, respectively. The consistency of the initial 65:35 milkfat/soybean oil mixture (1000 gf/cm 2 ) decreased to 732.35 AE 75.30 gf/cm 2 and to 478.02 AE 71.80 gf/cm 2 in interesterified blends catalyzed by Novozym 1 435 or by R. oryzae lipase, respectively. SFC was considered an inadequate parameter for following the interesterification of this blend formulation because the values were similar for initial and for interesterified blends. Free fatty acid levels of 1.5%, the non-notable deactivation of Novozym 1 435 and a half-life of 190 h for R. oryzae lipase were observed during the operation time.Practical applications: By interesterification of milkfat with soybean oil, a new product presenting higher spreadability than butter and richer in polyunsaturated fatty acids coming from soybean oil, was obtained. The Rhizopus oryzae lipase immobilized in an organic-inorganic hybrid matrix, used in a FBR for the modification of milkfat, promoted a higher reduction (approximately 52.0%) in the consistency of the interesterified products in relation to the initial reaction mixture than that obtained with Novozym 1 435 (approximately 27.0% reduction). Also, while Novozym 1 435 is as a non-specific lipase, the R. oryzae lipase presents sn-1,3 regioselectivity, which enables the maintenance of the unsaturated fatty acids at position sn-2 in triacylglycerols with well-known nutritional benefits. This biocatalyst showed a better performance than the immobilized commercial lipase (Novozym 1 435). The implementation of the interesterification in a continuous FBR results in lower shear rate imposed on the biocatalyst.

Correlation of the Solid‐Fat Content in Vegetable Oils with Other Parameters during Thermal Oxidation

“…SFC determination using TD‐NMR spectroscopy is a nondestructive and solvent‐free method and has been used in diverse application areas. For example, Domingues et al () determined the modification of solid properties in zero‐ trans fat made of oleogelators using SFC, and Paula et al () analyzed SFC after the reaction of milk fats with soybean oil by enzymatic interesterification.…”

Performance of packed bed reactor on the enzymatic interesterification of milk fat with soybean oil to yield structure lipids

“…The support was prepared by solegel technique and the resulting SiO 2 ePVA particles were neutralised and used to immobilise the R. oryzae lipase according previous procedure (Paula et al, 2015b). To perform this work, ten batches of immobilised derivatives were prepared, and the average measured hydrolytic activity was 4150 Ug À1 biocatalyst.…”

Síntese enzimática do caprilato de isopentila utilizando óleo fúsel como matéria-prima

“…Adicionalmente esta lipase na forma imobilizada apresentou elevado tempo de meia-vida quando utilizada em processos descontínuos (com reciclo do sistema imobilizado) 28 e contínuos. 29 Propriedades adicionais da lipase de R. oryzae imobilizada em SiO 2 -βCD revelaram os seguintes parâmetros na hidrólise do azeite de oliva:…”