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1.
研究了锁掷酵母与海洋红酵母中的类胡萝卜素,氨基酸、脂肪酸组成。锁掷酵母与海洋红酵母中的总类胡萝卜素含量分别为21.42 mg/L,8.02 mg/L。锁掷酵母中含有较多的β-胡萝卜素,而海洋红酵母中以红酵母烯为主。锁掷酵母中含有的β-胡萝卜素以全反式结构为主,全反式结构占总β-胡萝卜素的60%左右,顺式结构主要有13-顺和9-顺β-胡萝卜素。锁掷酵母和海洋红酵母中的蛋白质中均含有常见的20种氨基酸,不饱和脂肪酸占总脂肪酸的比例分别为74%和76%。文中对锁掷酵母与海洋红酵母中含有的类胡萝卜素、蛋白质和脂肪酸进行了比较分析,为锁掷酵母在饲料行业的深入应用奠定了基础。  相似文献   

2.
In this work, NIR and MIR spectroscopy was investigated and compared for predicting passion fruit ripening parameters as sugars, organic acids and carotenoids. Spectra of 56 samples of the lyophilized passion fruit were collected using an integrating sphere in NIR range and attenuated total reflectance accessory in MIR range. Individual sugars (sucrose, glucose and fructose), organic acids (malic and citric acids) and carotenoids (β-carotene) contents were determined by reference methods. Spectral and reference data were analyzed by principal component analysis. Partial least square regression (PLSR) was used to establish calibration models. MIR technique was better than the NIR technique for glucose (R2v = 0.942), fructose (R2v = 0.855), sucrose (R2v = 0.818), total sugar (R2v = 0.914) and citric acid (R2v = 0.913) content determination. On the other hand, NIR was superior for total acids (R2v = 0.903) content determination. For malic acid and β-carotene contents both methods were unsatisfactory due to low concentrations of these constituents in the passion fruits.  相似文献   

3.
《Food chemistry》2005,92(4):661-671
The aim of the present study was to investigate the preparation of β-carotene nanodispersions as potential active ingredients for food formulations. Nanodispersions containing β-carotene were obtained by a process based on an emulsification–evaporation technique. The preparation method consisted of emulsifying an organic solution of β-carotene in an aqueous solution containing emulsifier using two different homogenizers (a conventional homogenizer and a microfluidizer), followed by direct solvent evaporation under reduced pressure. The influence of different homogenizing conditions (pressure and cycle) and two organic/aqueous phase ratios on particle size parameters and content of β-carotene was investigated. In addition, the stability of β-carotene nanodispersions was carried out at a storage temperature of 4 °C. The particle size distribution of β-carotene in nanodispersions was demonstrated with a laser diffraction particle size analyzer and the retention of β-carotene in the prepared nanodispersions was studied by high-pressure liquid chromatography. In general, homogenization pressure and cycle had significant (P < 0.05) effects on various particle size parameters. A volume-weighted mean diameter (D4,3) of β-carotene nanoparticles, ranging from 60 to 140 nm, was observed in this study.  相似文献   

4.
A procedure for the quantitative analyses of major carotenoids and carotenoid esters in persimmons and papayas using column and liquid chromatography is described. The carotenoids and carotenoid esters were first separated by column chromatography on alumina into three fractions by elution with petroleum ether-benzene (80:20), benzene and methanol. The column fractions were further separated by reversed phase liquid chromatography and characterized. The total carotenoid contents in persimmon and papaya calculated as beta-carotene equivalents were 43 and 25 μg/g, respectively. The major carotenoids in persimmon were beta-cryptoxanthin, zeaxanthin, beta-carotene, lycopene and antheraxanthin and the major carotenoids in papaya were beta-cryptoxanthin, cryptoxanthin 5,6-epoxidc, beta-carotene and antherxanthin. The xanthophylls were acylated with C8 to C16 saturated fatty acids.  相似文献   

5.
光皮树油工厂化精炼及理化性质分析   总被引:1,自引:0,他引:1  
将从于都具收集到的光皮树干果压榨出毛油后,通过工厂化精炼,最终得到光皮树精炼油,并对其脂肪酸成分以及理化进行分析。结果表明,光皮树油最主要的3种脂肪酸为亚油酸(34.69%)、油酸(34.47%)、棕榈酸(22.37%)。对光皮树毛油与精炼油比较发现,毛油颜色深(黄77,红12,蓝8.7),高酸值(15.3mg KOH/g)和高过氧化值(76.9meq/kg),精炼后得到很大程度改善;一些营养成分(碳水化合物、水分、β-胡萝卜素、VE、尼克酸、硫胺素)和微量元素(钾、钠、镁、磷)在毛油中均有存在,经精炼后,碳水化合物、水分、β-胡萝卜素、钾、镁、磷含量显著下降,VE含量变化不大,尼克酸、硫胺素和钾含量均低于检测下限。  相似文献   

6.
β-Carotene has been widely investigated both in the industry and academia, due to its unique bioactive attributes as an antioxidant and pro-vitamin A. Many attempts were made to design delivery systems for β-carotene to improve its dispersant state and chemical stability, and finally to enhance the functionality. Different types of oil-in-water emulsions were proved to be effective delivery systems for lipophilic bioactive ingredients, and intensive studies were performed on β-carotene emulsions in the last decade. Emulsions are thermodynamically unstable, and emulsions with intact structures are preferable in delivering β-carotene during processing and storage. β-Carotene in emulsions with smaller particle size has poor stability, and protein-type emulsifiers and additional antioxidants are effective in protecting β-carotene from degradation. Recent development in the design of protein-polyphenol conjugates has provided a novel approach to improve the stability of β-carotene emulsions. When β-carotene is consumed, its bioaccessibility is highly influenced by the digestion of lipids, and β-carotene in smaller oil droplets containing long-chain fatty acids has a higher bioaccessibility. In order to better deliver β-carotene in complex food products, some novel emulsions with tailor-made structures have been developed, e.g., multilayer emulsions, solid lipid particles, Pickering emulsions. This review summarizes the updated understanding of emulsion-based delivery systems for β-carotene, and how emulsions can be better designed to fulfill the benefits of β-carotene in functional foods.  相似文献   

7.
The influence of a variety of additives and thermal treatments upon the rate at which green discoloration develops in β-carotene-hydrogenated fat systems is reported. The observed effects are discussed in relation to the hypothesis that the colour change is associated with the production of β-carotene epoxides from the oxidation of β-carotene by peroxy acids which are formed by the interaction of aldehydoglycerides with dissolved oxygen. Possible methods which might be employed in avoiding the incidence of the discoloration include suitable choice of oil, the use of certain additives, notably commercial lecithin (for food uses), adequate ‘tempering’ of the finished fat, and care in the use of cool (and cold) storage.  相似文献   

8.
采用体外消化法结合细胞吸收模型,以胶束化率为指标,研究了4种柑橘黄烷酮对β-胡萝卜素胶束化的影响。结果表明,β-胡萝卜素的胶束化率随胆盐浓度升高而增加,当胆盐浓度为15 mmol/L时,添加卵磷脂能显著增加β-胡萝卜素胶束化率(p<0.05)。橙皮苷对β-胡萝卜素胶束化的促进作用显著(p<0.05),橙皮素、柚皮素次之,柚皮苷作用不显著(p>0.05)。4种柑橘黄烷酮增加了β-胡萝卜素胶束极性,降低了胶束颗粒粒径,提高了胶束稳定性。在调控β-胡萝卜素的生物可利用率和细胞吸收方面,橙皮苷显著提高β-胡萝卜素的生物可利用率(p<0.05),橙皮苷、橙皮素、柚皮素均显著促进β-胡萝卜素的细胞吸收(p<0.05),而柚皮苷对β-胡萝卜素的细胞吸收促进作用不显著(p>0.05)。由此可见,类黄酮的加入会提高β-胡萝卜素的生物利用率。  相似文献   

9.
Total phenols, flavonoids, flavonols, and flavanols of the methanolic extract of the aerial part of Artemisia herba-alba were determined. The extract was analyzed by liquid chromatography with photodiode array coupled with electrospray ionisation mass spectrometry and allowed to identify of 10 phenolic compounds. Apigenin-6-C-glycosyl flavonoids and caffeoylquinic acids were identified. Chlorogenic acid and 1,4 dicaffeoylquinic acid being the major constituents. The essential oil obtained by hydrodistillation was analyzed by gas chromatography–mass spectrometry. Twenty-three compounds, representing 97.8% of the total oil, were identified. The most abundant components were β-thujone (41.9%), α-thujone (18.4%), and camphor (13.2%). Methanolic extract and essential oil exhibited a considerable antioxidant activity as evaluated by 2,2-diphenyl-pycrilhydrazil hydrate scavenging activity, reducing power, β-carotene bleaching test, and chelating ability. The methanolic extract was found to be more efficient, while the essential oil exhibited the highest acetylcholinesterase inhibitory activity. Analysis of the antibacterial activity showed that A. herba-alba methanolic extract and essential oil are efficient against gram positive and gram negative bacteria.  相似文献   

10.
An improved extraction and HPLC method for the simultaneous extraction and quantitation of retinol, α-tocopherol, α-tocotrienol, and β-carotene was developed to analyze commercial whole/semi-skim/skim samples of raw/pasteurized/UHT milk in transparent plastic/glass bottles and Tetra Brik? containers. The sample preparation method required prior saponification at 40 °C for 15 min followed by n-hexane extraction. An isocratic acetonitrile/methanol (65:35 v/v) mobile phase, C18 analytical column, and UV detector were chosen for HPLC quantification. The liposoluble vitamin content in raw, pasteurized conventional/organic, and UHT milk ranged 0.055–5.540 (retinol), 0.135–1.410 (α-tocopherol), and 0.040–0.850 mg/L (β-carotene). No significant differences (p > 0.05) were observed on losses of retinol, α-tocopherol, and β-carotene content in UHT whole milk after 5 days at 4 °C in the dark. After 14 days at 4 °C in the dark, the contents of retinol, α-tocopherol, and β-carotene remained higher in milk with higher fat content and were higher in unopened containers. In UHT whole milk, samples containing 0.02 % NaN3, retinol (33 %), and α-tocopherol (11 %) but not β-carotene (2 %) decreased significantly (p < 0.05).  相似文献   

11.
B.I. Abonyi    H. Feng    J. Tang    C.G. Edwards    B.P. Chew    D.S. Mattinson    J.K. Fellman 《Journal of food science》2002,67(3):1051-1056
ABSTRACT: The quality retention characteristics of strawberry and carrot purees dried using the Refractance WindowTM (RW) drying method were evaluated against freeze drying, drum drying, and spray drying methods. Ascorbic acid retention of the strawberry purees (94.0%) after RW drying was comparable to 93.6% in freeze-drying. The carotene losses for RW drying were 8.7% (total carotene), 7.4% (α-carotene), and 9.9% (β-carotene), which were comparable to losses of 4.0% (total carotene), 2.4% (α-carotene), and 5.4% (β-carotene) for freeze-dried carrot purees. The color of the RW-dried carrot purees was comparable to fresh puree. For RW-dried strawberry purees, the color retention was comparable to freeze-dried products. RW drying altered the overall perception of aroma in strawberries.  相似文献   

12.
In view of consumer health, it is desirable to promote the bioaccessibility of lipid-soluble compounds like carotenoids, while limiting the lipid intake. The objective of this work was to examine the relation between in vitro lipid digestion and β-carotene bioaccessibility of carrot-based model food emulsions containing water, 5% olive oil enriched with β-carotene (from carrots) and different concentrations (1–2–3–4%) of l-α-phosphatidylcholine (PHC), as an emulsifier. The lipid digestion (hydrolysis of triacylglycerols (TAGS) and incorporation of free fatty acids (FFAs) and monoacylglycerols (MAGs) in the micelles) and the β-carotene bioaccessibility (incorporation of β-carotene in the micelles) were studied after an in vitro digestion procedure wherein the stomach phase was mimicked for 2.0 h (37 °C) and the small intestinal phase was mimicked for 1.0 h, 1.5 h and 2.0 h (37 °C) (both end-over-end rotations). As a consequence, not only the influence of the emulsifier concentration, but also the influence of the duration in the small intestinal phase was investigated in this study. The oil droplet size distributions of the emulsions at different stages of digestion were shown to be dependent on the phosphatidylcholine concentration, but independent on the duration in the small intestinal phase (1.0 h–2.0 h). Furthermore, all TAGs were already hydrolysed into FFAs and MAGs after 1.0 h small intestinal phase and the incorporation of FFAs and MAGs into micelles seemed to reach a maximum for all emulsions (approximately 26.5%), independent on the phoshpatidylcholine concentration and thus on the particle size distributions. Finally, the β-carotene bioaccessibility increased with increasing phosphatidylcholine concentration, ranging from 33.2% to 79.8% for a 1% and 4% PHC emulsion respectively. No significant differences in β-carotene bioaccessibility were however noticed for the different durations in the small intestinal phase tested. In conclusion, a higher phosphatidylcholine concentration in emulsions leads to higher β-carotene bioaccessibility while the incorporation of lipids into micelles did not increase.  相似文献   

13.
《Food chemistry》2002,79(4):461-472
Green sea urchins (Strongylocentrotus droebachiensis), taken from the wild were fed on a grain-based artificial diet over a 9-week period. At intervals, the animals were harvested and the gonads analysed for proximate composition, lipid class distribution, fatty acid and carotenoid pigment compositions. During the feeding period the lipid content decreased and the moisture content increased. Meanwhile, the protein content was highest after 9 weeks of feeding on the artificial diet. Major non-polar lipid classes were triacylglycerol (TAG), free fatty acids (FFA) and sterols (ST) while dominant polar lipid classes were phosphatidylcholine (PC) and phosphatidylethanolamine (PE). The content of PC was much higher than that of PE on week 0. However, PE became dominant on week 9 after feeding on the artificial diet. The fatty acids 14:0 and 16:0 were the major saturated fatty acids (SFA), consistently present in the total, non-polar and polar lipids of sea urchin gonads. Polyunsaturated fatty acid (PUFA) 20:5n-3 (eicosapentaenoic acid, EPA) was the highest on week 0 while 18:2 n-6 became dominant with increased feeding period with a concurrent decrease in the content of 20:5n-3. Further, 20:1n-15 was the major monounsaturated fatty acid (MUFA) at week 0, but its content decreased significantly (P<0.05) after introducing the artificial diet. The total carotenoid content decreased by 50% at the end of the feeding period. Major carotenoids present in sea urchin gonads were echininone and β-carotene. The relative content of echininone was lowest at week 0, but increased when the urchins were fed on the artificial diet with a simultaneous reduction in β-carotene levels. The study demonstrates the importance of feed supply in lipid composition of sea urchin gonads.  相似文献   

14.
Solutions of all-trans-β-carotene in liquid paraffin were stirred under air at 210°C for 15 min in the presence and absence of various amino acids. After cooling, the absorbance values at 460 nm of model systems containing all-trans-β-carotene and phenylalanine, cysteine or tryptophan were 34–58 times higher than that obtained on heating in the absence of an amino acid. Based on absorbance values at 420 nm, 86% of the coloured material present on heating the all-trans-β-carotene-phenylalanine model system at 210°C for 15 min was retained by the liquid paraffin on methanol extraction. The liquid paraffin phase remaining after methanol extraction was analysed by reverse-phase HPLC and three major components were identified as all-trans-β-carotene and two degradation products of all-trans-β-carotene, ie 9-cis-β-carotene and a furanoid diepoxy derivative. None could be detected on heating all-trans-β-carotene alone, suggesting that its degradation was retarded on heating in the presence of phenylalanine.  相似文献   

15.
In this study, the antioxidant activities of Camelina sativa methanolic extracts were evaluated by different chemical assays: reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH·) assay, the β-carotene bleaching method and the metal chelating activity assay. An LC-MS profiling method was used for a comprehensive study of the phenolic compounds and their representation in camelina seeds, cake and oil. For this purpose, 4-vinyl derivatives of hydroxycinnamic acids were synthesized by thermal decarboxylation of the corresponding phenolic acids and sinapine was isolated from kale (Brassica oleracea) applying a new method and confirmed by NMR. The results revealed that besides the total phenolic content and antioxidant activity, seeds and cake also possess a similar phenolic profile. In addition to sinapine and 4-vinyl derivatives, other antioxidants were successfully identified: ellagic acid, protocatechuic acid, p-hydroxybenzoic acid, sinapic acid, salicylic acid, catechin, rutin, quercetin and quercetin glucoside. Since after oil pressing most of the phenolic compounds remain in the seed residues, only a few compounds were identified in the oil. Camelina cake was found to have the best reducing power and radical scavenging activity, whereas camelina oil, with a relatively low phenolic content, exhibited the highest iron-chelating capacity and the best inhibitory action against β-carotene discolouration in an emulsified system.  相似文献   

16.
The biological activity of lycopene can be enhanced by the presence of these other active antioxidants such as β-carotene, vitamin E, and vitamin C. Since many of these natural antioxidants are consumed together in foods, the potential for synergistic interactions is high in the human diet. The aim of this study was to determine what concentrations and combinations of antioxidants among lycopene, vitamin E, vitamin C, and β-carotene are capable of producing synergistic antioxidant effects, based on tomato-based food products. Solutions of the scavenging capacities of lycopene, vitamin E, vitamin C, and β-carotene, alone and in different combinations were measured using the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Three different levels of each antioxidant were used. A comparison of the scavenging capacity (antioxidant activity) of the combinations of antioxidants to the arithmetic sum of the scavenging capacities of the individual antioxidants was used to calculate the synergistic effects (SEs) between the antioxidants. The results showed that the mixture that had the highest SEs (P<0.01) was the solution combining lycopene (15 μmol/L), vitamin E (5.0 μmol/L), vitamin C (0.16 μmol/L), and β-carotene (10.83 μmol/L). The results suggest that the antioxidant property of this combination was substantially superior to the sum of the individual antioxidant effects, and these interactions can enhance the antioxidant effectiveness of natural antioxidants. The results could guide in the formulation and development of functional food products that have high antioxidant potential.  相似文献   

17.
The carotenoid composition of Brazilian Valencia orange juice was determined by open column chromatography (OCC) and high-performance liquid chromatography. Carotenoid pigments were extracted using acetone and saponified using 10% methanolic potassium hydroxide. Sixteen pigments were isolated by OCC and identified as α-carotene, ζ-carotene, β-carotene, α-cryptoxanthin, β-cryptoxanthin, lutein-5,6-epoxide, violaxanthin, lutein, antheraxanthin, zeaxanthin, luteoxanthin A, luteoxanthin B, mutatoxanthin A, mutatoxanthin B, auroxanthin B and trollichrome B. Thirteen carotenoid pigments were separated using a ternary gradient (acetonitrile–methanol–ethyl acetate) elution on a C18 reversed-phase column. Among these, violaxanthin, lutein, zeaxanthin, β-cryptoxanthin, ζ-carotene, α-carotene, and β-carotene were quantified. The total carotenoid content was 12 ± 6.7 mg/l, and the major carotenoids were lutein (23%), β-cryptoxanthin (21%), and zeaxanthin (20%).  相似文献   

18.
In order to give insight into β-carotene degradation mechanism during the storage of dried orange-fleshed sweet potato, and particularly into the role of isomers and norisoprenoids formation, multi-response kinetic modelling was applied. Determination of degradation compounds were carried out by HPLD-DAD and SPME-GC-MS as a function of time between 10 and 40 °C and at four water activities from 0.13 to 0.76. Kinetic modelling was developed assuming first-order reactions and by using mass balance. Eight compounds, namely, two isomers (9-cis- and 13-cis-β-carotene), two β-carotene epoxides (β-carotene 5,6 and 5,8 epoxide) and four volatile compounds (β-cyclocitral, β-ionone, 5,6-epoxy-β-ionone and dihydroactinidiolide), were integrated into two theoretical reaction schemes. The different models were discriminated according to goodness of fit to experimental data. This work showed that: (1) the formation of cis-isomers from β-carotene preceded oxidation, (2) β-cyclocitral arose directly from β-carotene scission while the other norisoprenoids resulted from β-carotene epoxide degradation, (3) cis-isomers were high reactive compounds. Temperature had a major influence on reaction rates k while water activities only impacted k at values under 0.51. Therefore, multi-response modelling is not only a tool to predict β-carotene degradation but a interesting way to select the appropriate degradation scheme based on the different options presented in literature.  相似文献   

19.
A leaf protein concentrate (LPC) prepared from cauliflower leaves was analysed for crude protein, calcium, phosphorus, iron, β-carotene and some of the amino acids. Lysine and tryptophan were present in nutritionally adequate amounts, but cystine and methionine were not: Cauliflower LPC was evaluated for its nutritional qualities in respect of growth rate, protein efficiency ratio (PER), liver nitrogen, and plasma protein content by feeding rats. The growth rate of rats and PER values of leaf protein supplemented diets were better than that of the wheat flour fed group. Hence, cauliflower LPC might be used for improving nutritionally poor diets.  相似文献   

20.
The present work reports amounts of flavonoids and phenylpropanoids of culms of three sugarcane varieties and of raw juice, syrup, molasse and VHP sugar. The antioxidant activity of those materials was evaluated by the DPPH and β-carotene/linoleic acid methods. The predominant phenolics in culms were phenylpropanoids (caffeic, chlorogenic and coumaric acids), while flavones (apigenin, tricin and luteolin derivatives) appeared in lower amounts. Differences were noted either among phenolic profiles of sugarcane culms or between culms and sugarcane products. The antioxidant activities of solutions from most samples were similar or higher than a 80 μM Trolox solution.  相似文献   

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