Extraction of Poppy Seed Oil Using Supercritical CO2

ABSTRACT: Extraction of poppy seed oil with supercritical carbon dioxide (SC-CO₂) was performed and the effect of extraction conditions on oil solubility and yield as well as oil composition was evaluated. Within the temperature (50 to 70 °C) and pressure (21 to 55 MPa) ranges studied, 55 MPa/70 °C gave the highest oil solubility (24.1 mg oil/g CO₂) and oil yield (38.7 g oil/100g seed). Fatty acid composition of the oil obtained with SC-CO₂ at 55 MPa/70 °C was similar to that of petroleum ether-extracted oil ( p > 0.05) with linoleic acid making up 69.0 to 73.7% of fatty acids. Tocol content of the SC-CO₂-extracted oils varied from 22.37 to 33.35 mg/100 g oil, which was higher than that of petroleum ether-extracted oil (15.28 mg/100 g oil). Poppy seed oil may have potential in the rapidly growing specialty oil market.     

Supercritical CO2 Extraction for Total Fat Analysis of Food Products

Supercritical CO₂ extraction (SFE) is a promising alternative to solvent extraction for the measurement of total fat in food products. Total fat was extracted by SFE from samples of food products of different compositions and fat contents. Results using SFE were statistically compared with those using standard methods. This feasibility study showed very promising results. A suitable method was developed for analysis of full milk powder and dietetic milk powder and recoveries were 97.4 and 98.4% respectively. The content of the major fatty acids of fat extracted with SFE was similar to that of Röse-Gottlieb solvent extraction.     

Supercritical CO2 Extraction of Oil from Atlantic Mackerel (Scomber scombrus) and Protein Functionality

Supercritical carbon dioxide (SC-CO₂) extraction temperature and pressure for oil removal from freeze-dried, fall Atlantic mackerel muscle were optimized. The effect of extraction conditions on pH and water-binding potential (WBP) of the protein residue was evaluated. For the temperature range (35–55°C) and pressure interval (20.7–34.5 MPa), 34.5 MPa/35°C gave highest oil yield and concentration of ω-3 fatty acids. SC-CO₂ extraction at higher pressure levels caused slight decreases in protein residue pH. WBP of residual proteins was maximal at 1.49g H₂O/g protein for 34.5 MPa/45°C. The high lipid removal and retention of protein functionality in the residue after oil extraction may make such processes useful for future food applications.     

Supercritical CO2 Extraction of Carotene and Lutein from Leaf Protein Concentrates

Supercritical fluid carbon dioxide was used to extract carotene and lutein from leaf protein concentrate (LPC). Extractions were performed using pressures of 10-70 MPa at 40°C and CO₂ flow rates of 5-6 L/min. Over 90% of the carotene contained in LPC was removed at extraction pressures in excess of 30 MPa. Removal of lutein from LPC required higher extraction pressures (70 MPa) and gas volumes to attain a 70% recovery level. Experimental results were rationalized with the aid of solubility parameter theory. The described process offers the possibility of obtaining a selective extraction of natural colorants, free of solvent residuals, which can be used as food dyes.     

Extraction Conditions and Moisture Content of Canola Flakes as Related to Lipid Composition of Supercritical CO2 Extracts

Canola flakes obtained before and after conventional cooking were extracted with supercritical carbon dioxide (SC-CO₂) at 35–75°C and 20.7–62.0 MPa. Moisture content was adjusted to 12.7–42.5% (w/w, moisture-and oil-free basis). Moisture content of residual flakes after extraction was monitored. Amount of extract recovered increased with increasing temperature and pressure, except at 20.7 MPa pressure it decreased with temperature indicating a crossover of the solubility isotherms. Some water was co-extracted with canola oil. Free fatty acid (FFA) concentration of the extracts increased with decreasing pressure due to a decrease in triglyceride (TG) solubility. Oleic and linolenic acids had highest concentrations in the FFA fractions of all extracts. The lowest TG content of extracts was attained at 20.7 MPa and 75°C. The effect of extraction conditions was more pronounced than seed pre-treatments on yield and composition of SC-CO₂ extracts.     

Supercritical CO2 Extraction of β-Carotene from Sweet Potatoes

Using supercritical CO₂ to extract β-carotene there was approximately a five-fold or a three-fold increase in amount of carotenoids extracted from freeze-dried tissue relative to the amount extracted from oven-dried or fresh tissue, respectively. The most efficient conditions were at 48°C and 41.4 MPa. Of the total carotenoid content ～20% was inaccessible to supercritical CO₂. The HPLC carotenoid profile of sweet potatoes showed that the unextracted tissue contained 90%β-carotene, primarily as all-trans (ca. 99%). Supercritical CO₂ extracts contained up to 94%β-carotene. The isomer composition of β-carotene of supercritical extracts showed ～ 14% 13-cis and 11% 9-cis.     

Supercritical CO2 Conditions Affecting Extraction of Lipid and Cholesterol from Ground Beef

Ground beef was extracted by supercritical CO₂ (SC-CO₂) with pressure ranging from 103-310 bar at 30-50°C. Higher pressure was needed to increase yield of extracted lipid. The profile of cholesterol content for the fractionated lipid extracted at 172 bar or 310 bar was generally lower in the initial stage of extraction and increased with CO₂ used. DSC thermograms indicated that, depending upon extraction conditions, the distribution of lipid components of fractionated samples either shifted toward higher melting temperatures or concentrated those lipids melting between 5-25°C.     

Supercritical CO2 extraction of grappa volatile compounds

A first study on the recovery of aromatic extracts from grappa by means of supercritical fluid extraction (SFE) on a laboratory plant has been performed, to obtain aroma extracts at low ethanol content. The influence of extraction parameters like pressure, temperature and flow rate have been studied. Extraction yields have been evaluated for ethanol, higher alcohols and esters of short and medium chain acids. A higher aroma volatile compounds extraction has been obtained when the strongest extraction condition has been considered (200 bar, 60 °C, 0.3 kg h⁻¹). Sensory evaluation has indicated as preferred the extract obtained under mild condition (80 bar, 40 °C, 0.3 kg h⁻¹).     

Reduction of Warmed-Over Flavor Volatiles from Freeze-Dried Lean by Supercritical CO2 Extraction

Supercritical carbon dioxide (SC-CO₂) was used to extract warmed-over flavor (WOF) volatiles from cooked, freeze-dried beef at 40°C and pressures of 10.3 MPa or 30 MPa after 2 days storage. WOF markers, hexanal, heptanal, octanal, nonanal, and 2,3-octanedione, were identified in the volatiles profile of precooked beef by dynamic headspace extraction and gas chromatography-mass spectrometry before and after CO₂ extraction. TBARS and levels of WOF markers increased over 2 days storage. There was a reduction in WOF markers at both extraction pressures. The higher pressure led to greater reduction of WOF markers (e.g., hexanal: 73.5%) than the lower pressure (e.g., hexanal: 60.3%), notably for heptanal and nonanal. SC-CO₂ may be applicable for reducing WOF volatiles from precooked meats.     

Effects of Substrate Densification and CO2 Conditions on Supercritical Extraction of Mushroom Oleoresins

The effects of densification of mushroom powders and of reduced density (p_r 1.15–1.45) and temperature (T_r, 1.105 – 1.195) of supercritical CO₂ (SCO₂) on solubilization of oleoresins were described by response surface methodology. Mushroom powder was compacted to specific volumes (v_d) between 0.825 and 1.125 mL/g and batch extracted with SCO₂ for 6 hr. The degree of solubilization (g oleoresin/100g solid) increased as p_r, T_r, or v_d increased. The effect of v_d was further studied for p_r= 1.45 and T_r= 1.197 using a 3-parameter diffusion model. It was postulated that a fraction of the oleoresin was easily extracted at a rate controlled by a diffusion coefficient of 1.0–1.5 × 10^?4 cm²/sec. The remaining constitutive and entrapped oleoresin was extracted at a rate regulated by a diffusivity 100 to 150 times lower, typical of diffusion through solids.     

Fat and Cholesterol Content of Beef Patties as Affected by Supercritical CO2 Extraction

Beef patties (raw, raw freeze-dried, cooked, and cooked freeze-dried) were prepared for treatment with supercritical carbon dioxide extraction (SC-CO). Each type of patty was then assigned to one of four treatments: control, static extraction at 170 atm/50°C, dynamic extraction at 170 atm/50°C and dynamic extraction at 544 atm/40°C. Freeze drying of the patties prior to SC-CO₂ extraction improved removal of fat and cholesterol. Freeze drying enhanced (P<0.01) cholesterol extraction; however, precooking had limited effects (P>0.05) on cholesterol extraction. Supercritical fluid extraction could be effective to reduce the fat and cholesterol content of preformed meat products, without requiring communication of the sample.     

Emulsifying Properties of Low-fat, Low-cholesterol Egg Yolk Prepared by Supercritical CO2 Extraction

Comparisons were made with native egg yolk, dried egg yolk and a commercial yolk substitute (soy lecithin). Aqueous emulsions were prepared by sonicating water containing 0–5% NaCl, 20% peanut oil, HC1 or NaOH as needed for pH adjustment, and 1–3% emulsifier expressed as the total of phospholipids, glycolipids and proteins contributed by yolk ingredients or soy lecithin. The median diameters of fat particles in the emulsions with and without dispersing fat droplet floes using Triton X-100, were evaluated by laser light diffraction. The emulsifying properties of low-fat, low-cholesterol egg yolk were similar to or better than those of native yolk and dried egg yolk. Soy lecithin had less effective emulsifying properties than yolk ingredients with respect to coalescence of fat droplets during storage and separation during 70°C treatment.     

Supercritical CO2 Extraction of Oil and Residual Proteins from Atlantic Mackerel (Scomber scombrus) as Affected by Moisture Content

Lipid composition of supercritical CO₂ (SC-CO₂) extracts, residual oil in muscle and changes in sarcoplasmic proteins after extraction of Atlantic mackerel were characterized. Dehydration of the muscle to 10.2% (w/w) resulted in high oil yield with minimum changes in protein content and composition. Sarcoplasmic protein content of fish muscle following SC-CO₂ treatment was lower than that of original muscles at all moisture levels (3.8–64%, w/w). Analysis of sarcoplasmic proteins by capillary electrophoresis indicated aggregation of low molecular weight proteins during SC-CO₂ extraction. SC-CO₂-extracted muscle also had lighter color than original samples. The SC-CO₂ extraction showed potential to provide high quality oil and protein meal.     

超临界CO2萃取枸杞色素中β—胡萝卜素研究

应用超临界ＣＯ２萃取分离技术,以枸杞油作为载体,从枸杞色素中分离萃取β－胡萝卜素,对其理化指标进行检测分析,为从枸杞色素中提取β－胡萝卜素作为制药原料奠定基础。     

Dynamic Changes of Headspace Gases in CO2 and N2 Packaged Fresh Beef

Two independent experiments were conducted to examine the effects of initial packaging/product conditions and storage conditions on in-package headspace pressure changes for modified atmosphere packaged beef during 12 hr storage. Headspace-to-meat volume ratio 1.8 to 5.9, surface area 200--800 cm², sample volume 0.22–0.75L, storage at 3–13°C and initial gas composition 20–100% CO₂ balanced with N₂ were studied. Headspace-to-meat volume ratio was the most important packaging parameter, but surface area and meat volume also affected headspace CO₂ changes. Decreased storage temperature reduced CO₂ concentration remaining in headspace. Higher initial CO₂ concentration resulted in greater concentration changes.     

Pecan Kernel Breakage and Oil Extracted by Supercritical CO2 as Affected by Moisture Content

During supercritical CO₂ extraction of oil from pecans, kernel breakage frequently occurs when the depressurization time is short. The purpose of this study was to investigate the effects of initial moisture content of pecan kernels and moisture equilibration time on pecan breakage and oil recovery when extracting with supercritical CO₂. Initial pecan moisture content, adjusted to 3.5% to 11.0%, had a significant effect on breakage when using a short depressurization time. With higher pecan moisture, less kernel breakage occurred. Increasing moisture equilibration time from 1 to 48 h reduced kernel breakage and produced an average of 30% more oil during extraction. Moisture content did not significantly affect the amount of oil extracted.     

PRODUCTION OF CO2 AND C2H4 AFTER GAMMA IRRADIATION OF STRAWBERRY FRUIT

Strawberry fruit (Fragaria ananassa, Duch. cv ‘Kent’) were irradiated at doses from 0 to 4 kGy and stored at 10°C to verify whether irradiation at very low doses could delay postharvest ripening while causing minimal damage to the tissues. CO₂ and C₂H₄ production were used as stress indicator. Anthocyanins and titratable acidity were measured as maturity parameters. CO₂ and C₂H₄ production increased six hours after irradiation. The increase in CO₂ production was proportional to the dose of irradiation and was highest at 4 kGy. Maximum C₂H₄ production was reached at 1 kGy. The different response of CO₂ and C₂H₄ production to irradiation suggests that the membrane system supporting C₂H₄ production was more sensitive to gamma rays than mitochondrial CO₂ production. Irradiation at 0.3 kGy slightly delayed color development in the fruit. Overall, the results indicated that it may be possible to use irradiation at a low dose to delay ripening while causing only minimal tissue damage.     

Static, Controlled (CO2) Atmosphere Packaging of Retail Ready Pork

Wrapped boneless pork loin roasts and slices were stored at 4°in bulk under constant CO₂ concentrations of 50% and 100% for 1 and 2 wks. Samples stored under 50% CO₂ for 2 wks could subsequently be displayed (aerobic) for 3 days without becoming unacceptable or for 6 days if previously held under 100% CO₂ for 14 days. Aerobic shelf-life at 4°of the latter samples equalled that of fresh pork chops under simulated retail display. Physicochemical characteristics during storage did not limit acceptability. Reusable master packs have application for distribution of retail ready cuts under controlled atmosphere packaging.