Structuring of oils with high PUFA content: Evaluation of the formulation conditions on the oxidative stability and structural properties of ethylcellulose oleogels.

This study evaluated the formulation of ethylcellulose oleogels as a fat substitute, based on oils with a high content of polyunsaturated fatty acids. Optimal processing conditions for canola, linseed, and chia oil oleogels were determined. The results showed that the oxidative stability was affected to a greater extent in chia oil oleogel, however, the addition of BHT improved the oxidative stability, mainly the peroxide value. Linseed and chia oil oleogels with a high content of polyunsaturated fatty acids (64.28 and 73.02 g/100 g, respectively) were obtained despite the reduction of these with respect to their oils, and no trans fatty acids were produced. Chia oil oleogels were shown to exhibit similar physical properties to linseed oil oleogels in terms of firmness (463.51 ± 7.42 g and 443.03 ± 7.14 g respectively) and rheological behavior. Such a structure led to a dominant elastic character of the oleogels to mimic the mechanical properties of animal fat.

Food-Grade Bigels with Potential to Replace Saturated and Trans Fats in Cookies.

Fats play multiple roles in determining the desirable characteristics of foods. However, there are health concerns about saturated and trans fats. Bigels have been proposed as a novel fat replacer in foods. This research evaluated the role of the type of hydrogel in the development of bigels to be used as fat replacers in cookies. Bigels were made with beeswax/canola oil oleogel and sodium alginate and carboxymethylcellulose hydrogels. The results showed that the peroxide value and binding capacity of bigels were affected by the type of hydrogel used. However, their fatty acid profile, p-anisidine value, oxidative stability, and texture remained unchanged. Using bigels as fat replacers, cookies were obtained with a hardness similar to those with original shortening, showing the potential of bigels for use in foods.

Enhancement of pigment extraction from B. braunii pretreated using CO2 rapid depressurization

Abstract Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21–49 °C) and pressure (6–13 MPa) during static compression on pigment recovery with supercritical CO2 at 40 °C, 30 MPa and solvent flow of 4.7 L NPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21 °C and 13 MPa as the cell disruption condition, which produced 1.91 g/kg d.s. of carotenoids and 14.03 mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22 mmol TE/kg oil) was significantly higher than the value for the untreated samples (29.11 mmol TE/kg oil) (p ≤ 0.05). Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds.

Enhancement of pigment extraction from B. braunii pretreated using CO2 rapid depressurization.

Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21-49°C) and pressure (6-13MPa) during static compression on pigment recovery with supercritical CO2 at 40°C, 30MPa and solvent flow of 4.7LNPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21°C and 13MPa as the cell disruption condition, which produced 1.91g/kg d.s. of carotenoids and 14.03mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22mmol TE/kg oil) was significantly higher than the value for the untreated samples (29.11mmol TE/kg oil) (p≤0.05). Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds.