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1.
The increase in the popularity of hemp-based products is mainly linked to the presence of non-psychoactive cannabinoids that provide relief from aches, pain and anxiety. In this study, hemp seed oils were produced by two innovative and environmentally friendly extraction techniques: supercritical and liquid carbon dioxide (CO2) extraction. The chemical composition of the two oils was analysed and compared with that of a control oil obtained by solvent (n-hexane) extraction. Both oils obtained by liquid and supercritical CO2 extraction presented interesting compositions: they contained large amounts of cannabinoids, polyphenols and tocopherols and were less oxidised than the control and contained a large amount of hexanal, which provided a pleasant aroma. The maximum cannabinoid content was found in the oil obtained by liquid CO2 extraction (71.51 mg of cannabidiol per kg of oil and 113.92 mg of cannabinol per kg of oil). Carotenoids were prevalent in the oil obtained by supercritical CO2 extraction (61.00 mg kg−1 of oil).  相似文献   

2.
An efficient pilot‐scale process was developed to produce nutraceutical products from fresh sea buckthorn (Hippophae rhamnoides) berries. Fresh berries were subjected to high‐pressure dewatering using a continuous screw press. The separated liquid phase containing 80–90% of pulp oil was clarified at 80 °C and centrifuged to obtain pulp oil, clear juice and sludge. The pulp oil yield was 2.7–2.8% of fresh berry weight with 66–70% extraction efficiency. The pulp oil was remarkably rich in carotenoids (2450–2810 mg kg?1), tocopherols (1409–1599 mg kg?1) and sterols (4096–4403 mg kg?1), with a characteristic fresh berry flavour and 16:1 as the major fatty acid (45.6–49.1%). The clear juice obtained was free from oil and contained high amounts of vitamin C (1683–1840 mg kg?1) and phytochemicals such as polyphenols (2392–2821 mg kg?1) and flavonoids (340–401 mg kg?1). Isorhamnetin (251–310 mg kg?1) was the major flavonoid in the juice, along with quercetin (77–81 mg kg?1) and kaempherol (12–16 mg kg?1). The juice was very acidic (pH 3), with high concentrations of organic acids (30.8–36.0 g kg?1). High‐performance liquid chromatography profiling of organic acids revealed quinic acid (18.1–19.9 g kg?1) as the major acid in the juice. The seeds in the pressed cake were separated and extracted for oil using supercritical CO2. Copyright © 2006 Society of Chemical Industry  相似文献   

3.
Decreasing effects of fluoride contents in Antarctic krill (Euphausia superba) as affected by chemical treatments with and without heating were investigated. The used chemicals were NaOH, Na2CO3, Na2SO3, citric acid, acetic acid, phosphoric acid, HCl, ethanol, lysine, aminoguanidine, arginine, carnitine, betaine, and creatine. Fluoride contents per dry weight were 788 ± 10 mg kg?1 in the whole body of krill (WBK) and 294 ± 4 mg kg?1 in the peeled krill meat (PKM) respectively. When WBK was treated with chemicals with and without heating or thawed, fluoride was not decreased. On the other hand, when the PKM was treated with chemicals without heating was remarkably decreased to less than 100 mg kg?1, which is the criteria recommended by FDA. Particularly, the treatment of betaine without heating showed the best reduction effect of 30 ± 6 mg kg?1, followed by carnitine (38 ± 17 mg kg?1), acetic acid (52 ± 1 mg kg?1), phosphoric acid (67 ± 2 mg kg?1) and hydrochloric acid (68 ± 1 mg kg?1).  相似文献   

4.
Oleoresin sage (Salvia officinalis) (SAG) (200–1500 mg kg?1), ascorbyl palmitate (AP) (100–300 mg kg?1) and TBHQ (200 mg kg?1) were assessed for delaying the thermo‐oxidation in sunflower oil (SO) during 18 h of frying (180 °C). Electronic nose compared the global aroma fingerprints of potato chips fried in oils. The chemical rancidity indices viz., fatty acids, total polar compounds (TPC), altered triglycerides (dimers, polymers, oxidised monomers, diglycerides), free fatty acids, conjugated dienes and induction periods were monitored along with physical indices viz., viscosity and colour. SOSAG+AP (1309.62 + 270.71 mg kg?1) outperformed SOTBHQ by preserving polyunsaturated fatty acids (60.48% vs. 56.23%), retarding TPCs (28.16% vs. 29.91%), triglyceride dimers (90.24 vs. 95.82 mg g?1) and polymers (25.40 vs. 26.98 mg g?1) concomitantly extending the oil disposal time (basis 25% TPC) (15.9 vs. 14.7 h). The postfrying viscosity, colour values and global aroma fingerprints of fried chips indicate a close match between SOSAG+AP and SOTBHQ.  相似文献   

5.
The aim of this study was to use waste from the wine production process with special accent on grape seeds and new green technology. Supercritical CO2 was considered as a green solvent in extraction of grape seed oil. The effects of different extraction process parameters on oil yield and antioxidant activity were investigated. Extraction optimisation was conducted using response surface methodology (RSM). Extraction pressure has proven to be the most significant factor influencing oil yield and antioxidant activity (< 0.0001). The optimal conditions for obtaining the highest oil yield and antioxidant activity within the experimental range of the variables studied were at extraction pressure of 400 bar and temperature of 41 °C. Under these optimal conditions, the predicted extraction oil yield was 14.49% and DPPH 37.07%. Applying this green extraction method, the oil from grape seeds was totally extracted. The produced oil was of satisfactory quality, and the content of α‐tocopherol in obtained grape seed oil at optimal extraction conditions was 36.05 mg kg?1.  相似文献   

6.
The objective of this study was to evaluate chemical and physical stability and consumers' acceptance of olive oil flavoured with oregano essential oils (EOs; Compacto, Cordobes, Criollo and Mendocino). Samples of olive oil were added with 0.05% EO and stored in dark (D) and light (L) conditions for 126 days. Samples with oregano EO had lower lipid oxidation indicator values [K232, K269, peroxide value (PV) and anisidine value], especially in darkness. Olive oil with Cordobes EO in D had the lowest PV (18.71 meqO2 kg?1). Using prediction equations, 20 meqO2 kg?1 PV in olive oil should be reached in 34 days in L control sample and in 126 days in the Cordobes EO sample in darkness. Samples with Cordobes and Criollo EOs in darkness had the highest chlorophyll content after 126 days (2.91 and 2.88 mg kg?1, respectively). Sensory analysis showed that oregano EO addition in olive oil was detected by panellists in discriminative test and affected consumer acceptance.  相似文献   

7.
BACKGROUND: Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti‐nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio‐diesel and glycerol). RESULTS: The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg?1) than in expeller oil (2.1 g kg?1). Liquid chromatography‐mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg?1) than in cake after being expelled (0.8 g kg?1). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg?1 and 8347 TIU g?1 of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L?1 of crude concentrate obtained from cake. CONCLUSION: Higher amounts of phorbol esters are present in oil than cake but bio‐diesel and glycerol are free of phorbol esters. The other anti‐nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
Grape seeds collected from vinification of various grape varieties were extracted by supercritical CO2 for oil recovery. The defatted residues thus obtained were considered as a re‐utilisable co‐product and assessed for phenolic content, reducing capacity and inhibitory activities against mammalian α‐amylase and α‐glucosidase enzymes. Supercritical CO2 treatment led to higher recovery of anthocyanins. Reducing capacity of phenolic extracts reached up to ~2200 mmolFe(II) kg?1, much higher than that of various natural phenolic sources. The anthocyanin‐rich extracts showed the highest inhibitory effectiveness towards α‐glucosidase (I50 value equal to ~40 μg gallic acid equivalents (GAE)/mL ~ half than acarbose). Inhibitory effectiveness towards α‐amylase activity was similar among grape varieties, with I50 values comparable to that of acarbose and correlated with proanthocyanidin contents. These results could pave the way for an efficient processing of grapes, including cascade processes, namely: winemaking, oil extraction from recovered grape seeds and phenolic extraction from defatted grape seeds as potential cost‐effective nutraceuticals.  相似文献   

9.
The aim of this was to improve n‐6/n‐3 ratio without affecting the volatile compounds profiles of pork. Different feeding strategies were designed for 60 Polish Landrace pigs with the goal to enhance the health attributes of Polish pork. Composition, colour, hardness, fatty acid contents and volatile compound profiles of the semimembranosus muscles were determined. Results showed that with the basic diet with the addition 3% of linseed oil, 100 mg kg?1 of vitamin E and 1 mg kg?1 of organic selenium, the level of polyunsaturated fatty acids (PUFA) in the meat samples was increased by 26% ( 0.05) as compared to the control. Principal component analysis (PCA) demonstrated that the aroma profile of semimembranosus muscles from pigs fed with the diet supplemented with 3% of linseed oil and 1 mg kg?1 of organic selenium was close to that of control. Results demonstrated that healthy functional meats could be produced by designing feeding strategies.  相似文献   

10.
This study investigated the impact of sprouting in four Indian onion varieties (Punjab White, Punjab Naroya, PRO‐6 and Commercial). Results showed significant (P < 0.05) increase in protein, crude fibre, ascorbic acid content, total phenol content, total flavonoid content, antioxidant activity, anthocyanin content and significant (P < 0.05) decrease in total carbohydrate, energy value and hardness due to sprouting in all the four varieties. HPLC analysis revealed irregular pattern of increase and decrease in flavonoid components. There was no particular trend observed within analysed flavonols due to sprouting in all the four varieties except with the maximum increase in quercetin (219.3–287.4 mg kg?1), kaempferol (13.8–17 mg kg?1), myricetin (34.6–40.9 mg kg?1), quercetin‐3?‐glucoside (2.9–4.1 mg kg?1) and quercetin‐4?‐glucoside (83–87.1 mg kg?1) in case of PRO‐6 variety only. The present research work implied sprouting to be beneficial in onion as nutritional and functional potential of all the four onion varieties was improved by sprouting.  相似文献   

11.
The quality of the oil of four safflower varieties, originating from Spain (Rancho), India (Sharda) and Morocco (Cartamar and Cartafri), which were cultivated at the experimental station in Oujda (a semi‐arid region of eastern Morocco) was evaluated through analysis of their phenolic and carotenoid contents. The composition of the phenolic compounds of safflower oil has not yet been documented. Therefore, in this preliminary study, Thirty different phenolic compounds were identified, and significant differences between the oil varieties were observed (P < 0.05). In the seed oil from the Rancho and Sharda safflower varieties, the main phenolic compound was trans‐chalcone, representing 13.45% and 11.8%, respectively, of the total phenolics, whereas in Cartamar and Cartafri oils, naringin accounted for 26.82% and 16.5%, respectively, of the total phenolics. The total carotenoid contents ranged from 1.13 mg kg?1 (Rancho) to 1.34 mg kg?1 (Cartamar and Cartafri). We observed that β‐cryptoxanthin (0.31–0.37 mg kg?1) and β‐carotene (0.3–0.35 mg kg?1) were the predominant carotenoids in all of the safflower oils that were studied.  相似文献   

12.
A 2‐step fermentation process was developed to enhance antioxidant activity of monascal waxy corn, fermented by Monascus purpureus TISTR 3090, compared with the conventional method. The results showed that, after 8 days of fermentation, monacolin K content and pigment intensity of monascal waxy corn from 2‐step fermentation were 62.89 mg kg?1 dry weight and 3072.70 unit g?1 dry weight, respectively, higher than those of the conventional method, while the residual reducing sugars were exhausted, giving the observed highest growth. The IC50 values of DPPH, ferric reducing/antioxidant powder (FRAP) and chelating ability on Fe2+ assays of the 2‐step fermentation were about 50% less than those of the conventional method. A significantly positive correlation was found between pigment intensity and monacolin K content, while significantly negative correlations were found among monacolin K content, IC50 of FRAP and chelating ability on Fe2+. An ideal negative correlation between pigment intensity and chelating ability on Fe2+ was found.  相似文献   

13.
The effect of supplementation of palm kernel oil in periwinkle flesh and palm kernel cake‐based diets on carcass characteristics and meat quality of broilers was evaluated. Birds were assigned to five dietary treatments in a completely randomized design. The first diet, which was the control, contained 20 mg kg?1 fishmeal but it did not contain palm kernel cake and periwinkle flesh. The second diet contained 20 mg kg?1 fishmeal, 250 mg kg?1 palm kernel cake but no periwinkle flesh. The third diet contained 60 mg kg?1 periwinkle flesh, 250 mg kg?1 palm kernel cake and no fishmeal. Present in the fourth diet were 250 mg kg?1 palm kernel cake, 30 mg kg?1 periwinkle flesh, no fishmeal and 20 mg kg?1 palm kernel oil. Similarly, the fifth diet contained 250 mg kg?1 palm kernel cake, 30 mg kg?1 periwinkle flesh, no fishmeal and 40 mg kg?1 palm kernel oil. Carcass measures and cuts were significantly influenced (P < 0.05) by dietary treatments. Diets 2, 3 and 5 gave significantly higher plucked dressed weights, total edible meat and total bone weights, respectively. Also carcass cuts were significantly increased (P < 0.05) in birds on periwinkle and palm kernel oil diets, with abdominal fat being highest in diet 5 having 40 mg kg?1 palm kernel oil. However, proximate composition, physical and sensory properties were not significantly (P < 0.05) influenced by dietary treatment. Results showed that carcass characteristics improved as compared to the control group. Copyright © 2005 Society of Chemical Industry  相似文献   

14.
As food ingredient, Anser cygnoides is farmed in large scale; however, its blood is underused. The characteristics, stability and antioxidant activities of P owder of farmed C ygnoides S erum (FACSP) were investigated. Results showed that FACSP was protein‐rich and displayed satisfactory antioxidant activities. In vitro analysis indicated that the IC50 values of 2, 2′‐azinobis‐(3‐ethylbenz‐thiazoline‐6‐sulphonate), 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals were 1.56, 2.76 and 39.55 mg mL?1, respectively. In vivo experiment showed that the activity of total superoxide dismutase and content of glutathione of the FACSP‐treated groups were enhanced, and the contents of malondialdehyde and protein carbonyl were decreased. The parameters of 400 and 800 mg kg?1 bw day?1 dose groups were equally or approximately to vitamin C. The FACSP shows potential as an antioxidant functional food at a dose of 400 mg kg?1 bw day?1.  相似文献   

15.
Resveratrol (3,5,4′‐trihydroxystilbene) and its glycoside piceid are phenolic compounds found to be beneficial to health. In this paper, resveratrol and piceid were successfully extracted from the Chinese traditional medicinal herb Polygonum cuspidatum (Hu Zhang in Chinese), with supercritical CO2 plus ethanol modifier. The effects of ethanol content, pressure and temperature on the yields of resveratrol and piceid were investigated. Results showed that the extraction pressure was the main factor for the effective extraction of the two substances in the presence of ethanol modifier, especially for piceid. The optimal extraction condition was obtained: 30 MPa, 50 °C, (100 ml l?1), ethanol and 20 kg h?1 of CO2, at which the yields of resveratrol and piceid were 7.1 g kg?1 and 16.0 g kg?1, respectively. The yields obtained by supercritical fluid extraction (SFE) was comparable with those obtained by traditional organic solvent methods, indicating that SFE is an alternative method for extraction of the two compounds. Copyright © 2004 Society of Chemical Industry  相似文献   

16.
The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA‐05 and its wild‐type variety Hwachia against aldose reductase, α‐glucosidase and α‐amylase were examined. The results indicated that the polyphenolics‐rich extracts obtained using 800 g kg?1 methanol and 500 g kg?1 ethanol demonstrated inhibitory activities against aldose reductase (IC50 of 0.36–0.46 mg mL?1) and α‐glucosidase (IC50 of 1.32–1.94 mg mL?1). The 500 g kg?1 ethanol extracts also showed α‐amylase inhibitory activities (IC50 of 70.11–80.22 μg mL?1). Subsequent extracts, prepared further with NaCl and H2O from precipitates of 800 g kg?1 methanol or 500 g kg?1 ethanol extracts, exhibited potent α‐amylase inhibitory activities (IC50 of 17.68–38.68 μg mL?1). A combination of 500 g kg?1 ethanol extraction plus a subsequent H2O extraction produced highest polyphenolics and α‐amylase inhibitors. The SA‐05 α‐amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA‐05 is an advantageous choice for producing anti‐hyperglycaemic compounds.  相似文献   

17.
BACKGROUND: Oil yield from avocado fruit may be influenced by fruit pre‐treatment and extraction method. Unripe and ripe avocado fruit pieces were deep‐frozen at ? 20 °C and either freeze‐dried or oven‐dried (80 °C). Oil yield from these samples was determined after extraction with hexane and supercritical carbon dioxide (SC‐CO2). The fruit samples were examined using scanning electron microscopy before and after oil extraction. RESULTS: Average oil yield from ripe fruit (freeze‐dried and oven‐dried combined) was 72 g kg?1 higher than from unripe fruit for SC‐CO2 extracts and 61 g kg?1 higher for hexane extracts. This may be due to enzymatic degradation of parenchyma cell walls during ripening, thus making the oil more available for extraction. Freeze‐dried samples had a mean oil yield 55 g kg?1 greater than oven‐dried samples for SC‐CO2 extracts and 31 g kg?1 higher for hexane extracts. However, oil yields from ripe fruit (freeze‐dried and oven‐dried) subjected to hexane extraction were not significantly different. All hexane extracts combined had a mean oil yield 93 g kg?1 higher than SC‐CO2 extracts. CONCLUSION: SC‐CO2 may be more selective and may create paths of least resistance through the plant material. Hexane, on the other hand, is less selective and permeates the whole plant material, leading to more complete extraction and higher oil yields under the experimental conditions. Copyright © 2007 Society of Chemical Industry  相似文献   

18.
It is difficult to preserve fresh shiitake mushroom (Lentinula edodes (Berk.) sing) partly because of the rapid deterioration of texture (softening or lignification). In this study, we developed a storage model in which tissue softening was induced to analyse the relationship between changes in firmness and alterations in cell wall chemical components as well as their metabolism. The results showed that the treatment group accumulated more CO2 and contained less O2 because of the poorer permeability in package. The contents of glucan and chitin in the treatment group decreased from 241.3 ± 13.2 mg g?1 and 46.3 ± 1.2 mg g?1 to 157.3 ± 11.2 mg g?1 and 18.0 ± 1.0 mg g?1 (P < 0.05) with the accumulation of CO2. The activities of major cell wall degradation‐related enzymes were enhanced in the softening model, and the expression levels of major genes that encode enzymes related to cell wall degradation were upregulated. Our results suggested that the softening of shiitake mushrooms induced by high CO2 was associated with the degradation of polysaccharides and glycosaminoglycan and that these changes were systematically regulated by alterations in the activities and expression levels of related enzymes and genes.  相似文献   

19.
This study evaluated the quality of oil extracted from yellowfin tuna (Thunnus albacares) by enzymatic hydrolysis (EHO) compared with oil extracted by traditional methods, such as the physical method of cooking and pressing after fishmeal production and the chemical solvent method. The oil extracted by EHO presented the lowest acidity (1.96% oleic acid) and peroxide indexes (5.14 mEq O2 kg?1 of oil) and the highest levels of eicosapentaenoic acid (6.05g 100 g?1) and docosahexaenoic acid (27.15 g 100 g?1), two omega‐3 fatty acids with high nutritional value. Importantly, oil extraction from yellowfin tuna heads using EHO produced oil rich in omega‐3s with no oxidation. This study shows that this extraction method greatly increases the value of fish by‐products and increases the competitiveness of the fishing industry.  相似文献   

20.
This study shows the industrial feasibility of using aqueous methods to produce antioxidative and hypolipidaemic polysaccharides from Laminaria japonica (LJP). Comparison was firstly made among the polysaccharides prepared using different extraction media, that is water alone (LJPW) and citric acid (LJPC), sulphuric acid, hydrochloric acid and phosphoric acid. LJPC enabled the highest extract yield (~11% dry weight), bile salt adsorption rate (~59% dry weight), ABTS radical scavenging activity (IC50 value 1.06 mg mL?1) and ORAC antioxidant activity (341.87 μmol Trolox g?1). In animal trial using diet‐induced high‐fat mice, oral administration of LJP produced with citric acid (LJPC) at a high dose (200 mg kg?1 body mass per day) enabled significantly higher serum HDL‐C, lower LDL‐C/HDL‐C and unaltered LDL‐C, whilst a medium dose (100 mg kg?1 body mass per day) significantly decreased LDL‐C. Administration of LJP produced with water (200 mg kg?1 body mass per day) significantly lowered serum LDL‐C. Therefore, LJP may provide dose‐dependent pharmacological and therapeutic effects to combat atherosclerosis through their hyperlipidaemic and antioxidant properties.  相似文献   

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