Linking Landscape, Environment, Agriculture and Food

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Production of human milk fat substitutes by interesterification of tripalmitin with ethyl oleate catalyzed by candida parapsilosis lipase/acyltransferase

Publication . Tecelão, Carla; Perrier, Véronique; Dubreucq, Eric; Ferreira-Dias, Suzana

In human milk fat, the saturated fatty acids,namely palmitic acid, are located at the sn-2 position of triacylglycerols (TAG) while unsaturated fatty acids (e.g. oleic acid) are esterified at position sn-1,3. Thus, sn- 1,3-dioleoyl-2-palmitoylglycerol (OPO) is the target TAG to be used as human milk fat substitutes (HMFS) in infant formulas. In this study, the noncommercial recombinant lipase/acyltransferase from Candida parapsilosis (CpLIP2) was immobilized in Accurel MP1000, and used as a biocatalyst for the interesterification of tripalmitin with ethyl oleate in a solvent-free medium, to obtain structured lipids used as HMFS. Different molar ratios (MR) of ethyl oleate to tripalmitin (2:1–8:1) were used. After 4 h reaction at 60ºC, about 30 mol% of oleic acid incorporation was already observed for all tested MR. An apparent equilibrium was reached after 8–24 h, with 32–51 mol% final incorporation, increasing with the MR. The incorporation of oleic acid into TAG was compared with the maximum predicted values when a random or a sn-1,3-regioselective biocatalyst was used. The obtained values are consistent with the maximum incorporation expected for a sn-1,-3-regioselective enzyme. In fact, the amount of oleic acid at position sn-2 was approximately 15% for all the MR tested, which is explained by the acyl migration phenomenon. CpLIP2 exhibited higher activity than most commercial immobilized lipases (e.g. faster reaction in solvent-free media, low enzyme load, and low MR needed), and showed a recognized sn-1,3 regioselective behavior.

2019Journal article

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Enhancing oxidative stability of sunflower oil by supplementation with prickled broom (Pterospartum tridentatum) ethanolic extract

Publication . Neves, Marta; Miranda, Andreia; Lemos, Marco F.L.; Silva, Susana; Tecelão, Carla

This study aimed to evaluate the effect of ethanolic extract of Pterospartum tridentatum flowers in the stability of sunflower oil. The extract was characterized regarding to its antioxidant activity by the 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) scavenging method (EC50 = 76.3 ± 2.6 μg/mL) and total phenolic content (200 ± 8 mg GAE/g). Extracts were added at 500 mg/L (E1) and 1,000 mg/L (E2), and after 30 days of storage at room temperature, E2 oil showed improved quality parameters,with a reduction of 22.4%,17.2%,and 45.6% in the values of acidity,peroxide,and p-anisidine, respectively.The extract also increased oil stability at 180 °C.After 27 hr, the acidity (0.216 ± 0.016 mg KOH/g) and the total oxidation value (TOTOX) (69.30 ± 0.26) values of E2 oil were significantly lower than the control. These results showed that P. tridentatum effectively improved the shelf-life and thermal stability of sunflower oil,being a promising source of antioxidants for edible oils processing.

2020Journal article

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