Modificação bioquímica da gordura do leite

Castro

et al. 2016

Braz. J. Food Technol.

Self Cite

This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Assessing the reaction conditions to mediate the milkfat-soybean oil enzymatic interesterification Determinação das condições reacionais para mediar a interesterificação enzimática da gordura do leite e do óleo de soja SummaryA food grade lipase from Rhizopus oryzae immobilized on a hybrid polysiloxane-polyvinyl alcohol matrix (SiO 2 -PVA) was used as the biocatalyst to mediate the interesterification reactions of a blend containing 65% milkfat and 35% soybean oil. All the reactions occurred in an inert nitrogen atmosphere in cylindrical glass reactors (80 mL) with 40 g of the milkfat-soybean oil blend. The influence of the following variables was evaluated: biocatalyst loading (250-1500 activity units per gram of blend), biocatalyst moisture content (5-20%), temperature (45-60 °C) and incubation time (2-48 h). The reactions were monitored by determining the free fatty acid content, triacylglycerol (TAGs) composition in carbon species, and the consistency of the interesterified (IE) products. The reaction conditions were set based on the parameters that provided a high interesterification yield and good consistency of the final product within the ideal range (200 to 800 gf cm -2 ). Hence the best results were obtained using a biocatalyst loading of 500 U g -1 of blend with 10% moisture content at 45 °C for 4 h. Under these conditions the consistency of the interesterified product was 539.7 ± 38 gf cm -2 . The results demonstrated the potential of the immobilized lipase to alter the TAGs profile of the milkfat-soybean oil blend, allowing for the production of structured lipids.Keywords: Rhizopus oryzae lipase; Milkfat; Soybean oil; Interesterification. ResumoLipase de grau alimentício de Rhizopus oryzae, imobilizada em uma matriz híbrida de polissiloxano-polivinilálcool (SiO 2 -PVA), foi usada como biocatalisador para mediar reações de interesterificação de uma mistura contendo 65% de gordura de leite e 35% de óleo de soja. Todas as reações ocorreram sob atmosfera inerte de nitrogênio, em reatores de vidro cilíndricos (80 mL) com 40 g da mistura. Avaliou-se a influência das seguintes variáveis: carregamento de biocatalisador (250-1.500 unidades de atividade por grama de mistura), umidade do biocatalisador (5-20%), temperatura (45-60 °C) e tempo de incubação (2-48 h). O progresso das reações foi monitorado pela determinação do conteúdo de ácidos graxos livres, da composição em triacilgliceróis (TAGs) em espécies de carbono e da consistência de produtos interesterificados (IE). As condições reacionais foram estabelecidas com base nos parâmetros que proporcionaram alto grau de interesterificação e consistência do produto final dentro da faixa ideal (200 a 800 gf cm -2 ). Neste contexto, os melhores resultados foram obtidos utilizando-se 500 U de biocatalisador por grama de mistura, com 10% de...

Section: Introductionmentioning

confidence: 99%

Assessing the reaction conditions to mediate the milkfat-soybean oil enzymatic interesterification

Castro

et al. 2016

Braz. J. Food Technol.

Self Cite

“…The modification of oils and fats by interesterification can be performed by a chemical route using metallic sodium or sodium methylate as catalysts. In this case, the fatty acid (FA) redistribution occurs at random, and high temperature and pressure conditions can also affect the final sensory properties of the product, resulting in the requirement for additional purification . Enzymatic interesterification using lipases (EC3.1.1.3; triacylglycerol acylhydrolases) can be advantageous for this process because milder conditions can be used, allowing reduced losses of oil or fats, fewer unit operations, lower requirements of investment capital, and decreased degradation of antioxidants, such as tocopherols .…”

Section: Introductionmentioning

confidence: 99%

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

Euro J Lipid Sci & Tech

Osório

et al. 2014

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.

“…, 2009; Zevenbergen et al. , 2009); thus, the edible oils industry has investigated the possibility of manufacturing products by interesterification of oils and fats without the generation of trans ‐fat (Wassell & Young, 2007; Nunes et al. , 2010).…”

Section: Introductionmentioning

confidence: 99%

“…However, partial hydrogenation of fatty acid residues present in these oils also leads to the formation of geometric isomers with a trans-configuration. Several recent nutritional studies have suggested a direct relationship between trans-fatty acid consumption and increased risk for coronary heart disease (Mayamol et al, 2009;Zevenbergen et al, 2009); thus, the edible oils industry has investigated the possibility of manufacturing products by interesterification of oils and fats without the generation of trans-fat (Wassell & Young, 2007;Nunes et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

Interesterification of milkfat with soybean oil catalysed by Rhizopus oryzae lipase immobilised on SiO₂‐PVA on packed bed reactor

Santos

et al. 2011

Int J of Food Sci Tech

The potential of the lipase from Rhizopus oryzae immobilised on SiO 2 -PVA to catalyse the interesterification of the milkfat with soybean oil in a packed bed reactor running on continuous mode was evaluated. The reactor operated continuously for 35 days at 45°C, and during 12 days, no significant decrease in the initial lipase activity was verified. Interesterification yields were in the range from 35 to 38%wt, which gave an interesterified product having 59% lower consistency in relation to non-interesterified blend. Results showed the potential of the lipase from Rhizopus oryzae to mediate the interesterification of milkfat with soybean oil in packed bed reactor, attaining a more spreadable product under a cool temperature. The biocatalyst operational stability was assessed and an inactivation profile was found to follow the Arrhenius model, revealing values of 34 days and 0.034 day )1 , for half-life and a deactivation coefficient, respectively.