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1.
João M. Rocha Paavo J. Kalo F. Xavier Malcata 《European Journal of Lipid Science and Technology》2010,112(10):1138-1149
This research effort was aimed at assessing the changes in extractable neutral lipids (NL) throughout the baking process of Broa, a Portuguese traditional sourdough bread. NL were accordingly isolated, purified and quantitated – starting from non‐starch lipid (NSL) and starch lipid (SL) extracts of maize and rye flours, as well as fermented dough and bread. NSL accounted for the major fraction of extracted lipids; furthermore, the NSL/SL ratio evolved throughout processing in agreement with the phenomena prevailing during dough preparation, fermentation, and baking. An analytical method based on resolution by normal‐phase HPLC coupled with detection by evaporative light scattering was accordingly developed for quantitation of the aforementioned NL classes. Distinct NL classes correlated well with the stage of bread making. The main NL in NSL were triacylglycerols (ca. 75% of the total), but relatively high concentrations of sterol esters and diacylglycerols were also found. Conversely, free fatty acids were the dominant component of SL, whereas monoacylglycerols and free sterols were comparable to those in NSL. 相似文献
2.
João M. Rocha Paavo J. Kalo F. Xavier Malcata 《European Journal of Lipid Science and Technology》2012,114(3):294-305
Broa is an example of bread that is a good candidate for inclusion in functional diets, so it deserves further in‐depth study of its chemical composition—namely with regard to evolution of the lipid profile throughout breadmaking, in order to assess whether mixing, fermentation, or baking affect its nutritional value (in terms of unsaturated fatty acids, UFA) based on the assumption that neutral lipids (NL) can be protein‐ or carbohydrate‐bound. Hence, constituent fatty acids in NL of maize (Zea mays) and rye flour (Secale cereale), and in sourdough and final broa manufactured from a mixture therefrom were quantitated. Methodologies of esterification of fatty acids, as well as of transesterification of acyl lipids and sterol esters (SE) were improved. The n‐hydrocarbons containing between 4 and 24 carbon atoms were then resolved and identified by gas–liquid chromatography. Regarding total neutral lipids (TNL) in all samples, 79–89% were TAGs, and 87–93% were TAGs and DAGs in the case of free lipids (FL). Furthermore, 73–85% of TNL in bound lipids (BL) and 65–80% of TNL in starch lipids (SL) were TAG and free fatty acids (FFA). Conversely, only 4–5%, 6–16%, and 7–10% of TNL in FL, BL, and SL, respectively, were SE and MAGs. TAGs and DAGs underwent partial hydrolysis during fermentation and baking; palmitic, oleic, and linoleic acids were dominant as products released. The nutritional value of broa lipids was apparent owing to their proportions of SE (4%) and DAG (9%), coupled with 52% of linoleic acid in all samples—as well as to the high contents of polyunsaturated versus monounsaturated or saturated fatty acids, and to the general dominance of UFA. 相似文献
3.
Sena Bilgi? Ne?e ?ahin Ye?il?ubuk 《Journal of the American Oil Chemists' Society》2012,89(11):1971-1980
In this study, our aim was to enrich olive oil with stearidonic acid (SDA) together with polyunsaturated fatty acids (PUFA) by lipase-catalyzed acidolysis using olive oil (OO) and free fatty acids of Echium oil, in the presence of Lipozyme? TL IM. The reaction conditions were optimized by using response surface methodology. A three-factor, five level central composite circumscribed designs was used to generate the design points. The factors chosen were: substrate molar ratio (S r, 4–6?mol/mol), reaction temperature (T, 55–65?°C), and reaction time (t, 6–9?h). Targeted incorporation (5?%) of SDA into OO was achieved at substrate molar ratio of 6?mol/mol, 55?°C, and 8.4?h. Model verification performed under these conditions for mg- and g-scale production yielded SDA contents of 4.9 and 4.8?%, respectively. Moreover, it was observed that the structured lipid (SL) obtained under optimum conditions contained approximately 42?% oleic acid and 43?% PUFA including linoleic acid, α-linolenic acid, and γ-linolenic acid. Omega-6/omega-3 fatty acid ratio of SLs was 0.7. Analysis of oxidative properties resulted in lower oxidative stability of SL than unmodified OO. This type of SL containing SDA and other PUFA is believed to be beneficial for human health. 相似文献
4.
John W. Parry Zhihong Cheng Jeffrey Moore Liangli Lucy Yu 《Journal of the American Oil Chemists' Society》2008,85(5):457-464
Cold-pressed seed flours from pumpkin, parsley, mullein, cardamom, and milk thistle were examined for total oil, fatty acid
profile of the oil, total phenolic content (TPC), scavenging activities against peroxyl (ORAC), hydroxyl (HOSC) and 2,2-diphenyl-1-picrylhydrazyl
(DPPH) (RDSC) radicals, and antiproliferative capacity against HT-29 human colon cancer cells. The cold-pressed parsley seed
flour contained a very high concentration of total oil—17.6 g/100 g flour—with primarily C18:1 fatty acid at 86.2 g/100 g
fatty acids. All other flour oils had relatively high levels of saturated fats, ranging from 39.0 to 62.9 g/100 g fatty acids.
The tested seed flours demonstrated significant TPC and free radical scavenging activities. Milk thistle seed flour had the
highest TPC value of 25.2 mg gallic acid equivalent per g flour (GAE mg/g) followed by that of parsley seed flour at 8.1 GAE
mg/g. Milk thistle seed-flour extract also had significantly higher antioxidant activities than all other extracts against
all tested radicals. The milk thistle seed-flour extract had an ORAC value of 1131 μmol trolox equivalents (TE) per g flour
(TE μmol/g), a HOSC value of 893 TE μmol/g, and an RDSC value of 61 TE μmol/g. Also, ORAC, HOSC, and TPC values were significantly
correlated (P < 0.01) under the experimental conditions. The cold-pressed milk thistle seed flour inhibited the proliferation of HT-29
cancer cells in a dose-dependent manner. Results from this study suggest that these cold-pressed seed flours may serve as
natural sources of antioxidants and may be used to improve human health. 相似文献
5.
Renming Yang Honglun Wang Nianhua Jing Chenxu Ding Yourui Suo Jinmao You 《Journal of the American Oil Chemists' Society》2012,89(12):2269-2278
Supercritical CO2 extraction (SC-CO2) of fenugreek (Trigonella foenum-graecum L.) seed oil and its chemical composition and antioxidant activity were investigated. A central composite design combined with response surface methodology was used to study extraction conditions including pressure, temperature, and time. The optimum extraction conditions were 28.5?MPa extraction pressure, 41?°C extraction temperature, and 118?min extraction time, where 3.78?% yield was predicted. Fenugreek seed oil extracted under optimum conditions by SC-CO2 was mainly composed of 28.3?% C18:3, 33.45?% C18:2, 9.89?% C16, 8.1?% C18:1, 3.7?% C18, 0.71?% C20, and 0.61?% C22. The fenugreek oil was rich in unsaturated fatty acids (nearly 70?% of the total fatty acids), and polyunsaturated fatty acids accounted for 61.42?% (mass percentage) of the total amount. The 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity increased from 12.5 to 88.4?% when the concentration was increased from 1 to 12?mg/ml. The reducing power of the seed oil was concentration-dependent. The antioxidant activity of the supercritical fluid extraction extract was superior to those obtained by Soxhlet extraction. 相似文献
6.
Garima Pande Jamal S. M. Sabir Nabih A. Baeshen Casimir C. Akoh 《Journal of the American Oil Chemists' Society》2013,90(9):1311-1318
Structured lipids (SLs) containing palmitic, oleic, and docosahexaenoic acids for possible use in infant formulas were synthesized by enzymatic acidolysis reactions. The substrates used were tripalmitin, extra virgin olive oil free fatty acids (EVOOFFA), and docosahexaenoic acid single cell oil free fatty acids (DHASCOFFA) in 1:1:1, 1:2:1, 1:3:2, 1:4:2, and 1:5:1 molar ratios. Reactions were carried out at 65 °C for 24 h using Lipozyme® TL IM lipase. The products were analyzed for total and positional fatty acids by GC-FID, triacylglycerol (TAG) molecular species by HPLC-ELSD, and thermal behavior by DSC. The SLs, SL132, SL142, and SL151 had desirable fatty acid distribution for infant formula use with nearly 60 mol% palmitic acid at the sn-2 position and oleic acid predominantly at the sn-1,3 positions. The total DHA content of SL132, SL142, and SL151 were 7.54, 6.72, and 5.89 mol%, respectively. The major TAG molecular species in the SLs were PPP, OPO, and PPO. The melting completion temperature of SL132 was 37.1, 35.2 °C in SL142, and 32.9 °C in SL151. The SLs synthesized in this study have potential use in infant formulas. 相似文献
7.
M G Vásquez Carrillo M L Ortega Delgado E Estrada Lugo 《Archivos latinoamericanos de nutrición》1991,41(4):620-630
In order to utilize hardened beans, we proposed to find the method most indicated for the preparation of bean flour to determine their nutritional value, and to make bread of high industrial, nutritional quality, and good sensory characteristics, using blends of bean and wheat flours. Two types of flour were prepared, testing four soaking temperatures (22, 30, 40 and 50 degrees C) and two methods to remove the testa (under moist and dry conditions). At laboratory level, the dry testa removal method gave the best flour yields (mean = 85.8%) and the highest protein content (mean = 23.7%). Comparison between soaking temperature at 30 and 50 degrees C was not significant (alpha = 0.05). At pilot plant level, with soaking at 50 degrees C the flour yields were 58.0% for moist testa removal (H1) and 74.0% for dry removal (H2), with a protein content of 22.6% for H1 and 23.0% for H2. The H1 and H2 flours were added to wheat flour at 5, 10 and 15% for bread making. The addition of 5.0% gave breads with similar protein content and sensory characteristics to those of the control, wheat. A diet based on bean-flour bread resulted in greater weight gains than that with casein for gold hamsters. The study also demonstrated the importance of heat-treating of the bean flours, because when flour without previous heat treatment was administered, the animals lost weight and died. This effect was overcome by the process of baking the flours at 140 degrees C for four hours. 相似文献
8.
O. K. Chung Y. Pomeranz R. M. Jacobs 《Journal of the American Oil Chemists' Society》1984,61(4):793-797
Lipids were extracted with a series of solvent systems whose solubility parameter (δ) values ranged from 7.27 to 12.92 (hexane
and its aqueous azeotrope, benzene, acetone and its azeotrope and 2-propanol and its azeotrope) from a flour with 1.2%, 7.2%
or 13.8% moisture content (MC). The extracted total lipids (TL) were fractionated into nonpolar lipids (NL) and polar lipids
(PL) by silicic acid column chromatography. NL and PL were further subfractionated by thin layer chromatography (TLC). PL
were separated into glycolipids (GL) and phospholipids (PhL). TL, NL and PL extractabilities were affected by both flour MC
and by the nature and composition of extractants: the overall solvent effects were substantially more pronounced than the
flour MC effects. Free fatty acid and digalactosyldiglyceride (DGDG) extractabilities increased for all extractants, in general,
as flour MC increased. Significant linear relations between the δ values of extractants and the average amounts of TL, PL,
GL and PhL from flours with 3 MC were found. The high correlation (r=0.981) between δ and extractability of TL was primarily
caused by PL; extractabilities of monoglycerides (among NL) and all classes of GL and PhL were significantly (at the 0.01
level) linearly related to the δ values at all 3 flour MC levels. The present study indicated no selective binding between
flour proteins and a specific PL class. Among PL, DGDG showed a clear-cut breaking point in irreversible restoration of breadmaking
characteristics. Thus, the present study confirms the significant role of PL to breadmaking, resulting primarily from the
contribution of DGDG.
Presented in part at the AOCS Meeting, San Francisco, 1979. 相似文献
9.
Cyathophorella adiantum (Griff.) M. Fleisch. (Division-Bryophyta, Family-Daltoniaceae), an Eastern Himalayan moss was studied for the first time to identify the volatiles derived from cellular and membrane bound fatty acids. A high capacity sample enrichment probe (SEP) was used for extraction of headspace volatile (HSV) molecules followed by GC–MS analysis. Different short-chain oxylipins like alkenes, alkanes, saturated and unsaturated alcohols, saturated and unsaturated aldehydes, ketones were identified along with free and esterified fatty acids, cyclo compounds and some by-products of secondary metabolites. Fatty acid analysis of neutral lipids (NL) and phospholipids (PL) of this plant exhibits the predominance of C16 and C18 fatty acids. It also reveals some interesting information that might indicate the possible fatty acid precursors for volatile generation and their sources in this plant. 相似文献
10.
Research regarding the production of gluten-free bread (GFB) is very important nutritionally, technically and economically speaking, both to celiac patients and to developing countries who import wheat. The main technological problem in the production of GFB is obtaining a gluten substitute that is both inexpensive and capable of retaining gas during bread fermentation and baking. The use of gelatinized starch as an alternative for gluten seems promising. In this project, rice bread was made using pregelatinized extruded rice flour as a gluten substitute. Pre-gelatinized rice flours (PRF) were manufactured in a single screw Brabender extruder, varying extrusion temperature (108-192 degrees C) and the moisture of the raw material (19.2 - 24.8%), and were used in a proportion of 10 g for every 100 g of raw rice flour, in the production of gluten-free bread. Results showed that rice flour extruded at a high temperature (180 degrees) and low moisture content (20%), rendered bread with the best technological characteristics, presenting crust and crumb color similar to those of conventional wheat bread, although with volume and texture not as satisfactory in the same comparison. 相似文献
11.
Maria Birkou Dimitris Bokas George Aggelis 《Journal of the American Oil Chemists' Society》2012,89(11):2047-2055
Nannochloropsis oculata and Chlorella sp. were cultivated in industrial scale bioreactors 300?L, under full sunlight and artificial light during night-time at various temperatures. The most abundant fatty acids were C18:3n-3 and C16:0 in Chlorella sp., whereas in N. oculata C16:0, eicosapentaenoic acid (EPA) and C16:1n-9 were predominant. Brachionus plicatilis cultivated in 2,500-L tanks on N. oculata, Chlorella sp. and Saccharomyces cerevisiae, was able to de novo synthesize as well as to elongate and desaturate pre-existing fatty acids in the feed. When fed with S. cerevisiae, B. plicatilis synthesized lipids containing EPA and docosahexaenoic acid (DHA), despite the fact that these fatty acids were absent in yeast lipids. Brachionus fed with Nannochloropsis synthesized DHA in non-negligible quantities. Brachionus enriched with various commercial preparations incorporated into its lipids substrate fatty acids but also synthesized new fatty acids such as C16:1n-9, C18:1n-9, C18:2n-6, EPA and DHA. Neutral lipid was the main lipid fraction while phospholipids predominated over glycolipids plus sphingolipids. The major amounts of EPA and DHA were observed in neutral lipids, noteworthy quantities of these fatty acids were also incorporated into body phospholipids. Interestingly, the high n-3 fatty acids content of rotifer lipids was retained even after the rotifers were grown in low n-3 fatty acid media. 相似文献
12.
Tadeusz Jakubczyk Hanna Haberowa 《Journal of the American Oil Chemists' Society》1974,51(1):120A-122A
Effect of soy flour, soy protein concentrate, and isolate on dough and loaf properties of breads produced from flour, yeast,
salt, and water with no shortening or added improvers was investigated. Wheat flour, rye flour, and mixtures of the two were
included in the studies. Three wheat flours, varying in baking quality and extraction, ash content 0.65 and 0.80%, were used;
1.5, 3, and 5% soy products, flour basis, were added. Water absorption increased 3.8–4.7% at the 3% soy level and 6.1–7.3%
at the 5% level of soy product addition. Dough development time and stability were increased and dough softening reduced.
Dough gassing power increased ca. 7–25%. By using a shorter proofing time, more intensive mixing, and the sponge dough process,
loaves only slightly smaller in volume than the control were obtained at the 3% soy level. Panel evaluations scored bread
highest with 1.5 or 3% soy flour and that with 3 or 5% soy protein concentrate as lowest, but acceptable. Use of 2% lard as
shortening, or 2% lard plus emulsifier, produced soy breads of excellent quality and ca. 25% higher loaf volume than controls. 相似文献
13.
Enzymatic Synthesis of Tyrosol-Based Phenolipids: Characterization and Effect of Alkyl Chain Unsaturation on the Antioxidant Activities in Bulk Oil and Oil-in-Water Emulsion
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Oxidative stability of lipids is one of the most important parameters affecting their quality. Lipase‐catalyzed lipophilic tyrosyl esters with an equivalent carbon alkyl chain but different degrees of unsaturation (C18:0 to C18:4n3) were prepared, characterized, and used as antioxidants. Free fatty acids and fatty acid ethyl esters (substrate molar ratio tyrosol: acyl donor, 1:10) were used as acyl donors and immobilized lipase from Candida antarctica was the biocatalyst (10 %). The phenolipids were isolated and characterized using ESI–MS, 1H‐NMR, and 13C‐NMR. Peroxide value (PV) and para‐anisidine value (p‐AV) were measured to evaluate their antioxidant activities in bulk oil structured lipid (SL) and in an oil‐in‐water emulsion (SL‐based infant formula). No significant difference was found in yield and reaction time between the two types of acyl donors. However, as the unsaturation of the fatty acids increased the reaction time also increased. In SL, tyrosyl esters exhibited lower antioxidant activity than tyrosol whereas the addition of an alkyl chain enhanced the antioxidant efficiency of tyrosol in infant formula. Tyrosyl oleate was the most efficient antioxidant in the emulsion system followed by tyrosyl stearate and tyrosyl linoleate. These results suggest that the synthesized phenolipids may be used as potential antioxidants in lipid‐based products. 相似文献
14.
Enzymatic synthesis of trans-free structured margarine fat analogues from stearidonic acid (SDA) soybean oil and high stearate soybean oil was optimized using response surface methodology. The independent variables considered were the substrate molar ratio (2–5), temperature (50–65 °C), time (6–22 h), and enzymes (Lipozyme® TLIM and Novozym® 435). The dependent variables were mol% stearic acid incorporation and mol% SDA content. A good-fit model was constructed using regression analysis with backward elimination and verified by a Chi-square test. Desirable and optimal products composition were achieved at 50 °C, 18 h, 2:1, using Lipozyme TLIM, with 15.6 mol% stearic acid and 9.2 mol% SDA in the product and at 58 °C, 14 h, 2:1, using Novozym 435, with 14.8 mol% stearic acid and 6.4 mol% SDA. Using optimal conditions, structured lipids (SL) were synthesized in a 1 L stir-batch reactor and free fatty acids removed by short-path distillation. SL were characterized for their fatty acid profile, sn-2 positional fatty acids, triacylglycerol profile, polymorphism, thermal behavior, and solid fat content. The SL had a desirable fatty acid profile, physical properties, and a suitable β′ polymorph content. These SL could be used as margarine fat analogues and an alternative to partially hydrogenated fat. 相似文献
15.
U. Biermann A. Wittmann W. Grosch 《European Journal of Lipid Science and Technology》1980,82(6):236-240
Occurrence of Bitter Hydroxy Fatty Acids in Oat and Wheat Water suspensions of oat, soft wheat, and durum wheat flours were incubated for 4.5 h at 38° C. Only the oat flour became intensely bitter. Freeze-dried samples of the incubated flours were analyzed for free hydroxy fatty acids with bitter taste. 750 μg/g L-OH (mixture of 9-hydroxy-trans, cis-10,12-octadecadienoic acid and 13-hydroxy-cis, trans-9,11-octadecadienoic acid) and 62 μg/g Tri-OH (mixture of 9,12,13-trihydroxy-trans-10-octadecenoic acid and 9,10,13-trihydroxy-trans-11-octadecenoic acid) were found in oat flour. Soft wheat flour contained the same amount of Tri-OH as oat flour but only 60 μg/g LOH were detected. Considerable less amounts of both L-OH and Tri-OH (20 μg/g and 15 μg/g respectively) were found in durum wheat flour. The bitter taste of oat flour which has been debittered by extraction of the lipids could be restored by addition of a mixture of 750 μg/g L-OH and 62 μg/g Tri-OH. 相似文献
16.
The antioxidant effects of oil‐in‐water nanoemulsion based on edible citrus peel essential oils on the fatty acid composition of rainbow trout fillets stored at 4 ± 2 °C are investigated. Fish fillets are treated with nanoemulsion and stored for 16 days. Lipid samples are converted into fatty acid methyl esters which are then detected by gas chromatagrophy (GC). The results show that palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), vaccenic acid (C18:1?‐7), oleic acid (C18:1?9), eicosenoic acid (C20:1?9), linoleic acid (C18:2?6), linolenic acid (C18:3?3), eicosapentaenoic acid (EPA) (C20:5?3), and docosahexaenoic acid (DHA) (C22:6?3) are the most important fatty acids in fish meat. While polyene index and hypocholesterolemic:hypercholesterolaemic fatty acid ratios decrease in trout fillets during cold storage, thrombogenicity index and atherogenicity index generally increase (especially in control and Tween 80 groups). The concentrations of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) are higher in the treatment groups and the saturated fatty acids (SFAs) are lower in all groups compared to those of the control group. Application of nanoemulsion based on citrus essential oils prevents oxidation of PUFA especially EPA and DHA, thus has potential as a preservative for fish oil. Practical Applications: In recent years, nanotechnological applications have been increasingly applied to the protection of food. Similarly, natural essential oils are used to increase the shelf life of foods. This study demonstrates the combined effect of a new method of nanoemulsions and essential oils on the safety of foods. 相似文献
17.
David L. Compton Joseph A. Laszlo Michael Appell Karl E. Vermillion Kervin O. Evans 《Journal of the American Oil Chemists' Society》2012,89(12):2259-2267
The effect of desaturation from the C9 to the C15 carbon of 2-monoacylglycerol (2-MAG) fatty acids on spontaneous acyl migration is described. Three 2-MAG species, 2-monooleoylglycerol (C18:1 cis-Δ9), 2-monolinoleoylglycerol (C18:2 cis-Δ9,12), and 2-monolinolenoylglycerol (C18:3 cis-Δ9,12,15) were synthesized by lipase-catalyzed ethanolysis of their respective triacylglycerols and isolated in >60?% yield and at 2-MAG purities of >95?% relative to 1-monoacylglycerol (1-MAG). 1H-NMR spectroscopy was used to monitor the spontaneous acyl migration of the 2-MAG species over a temperature range from 20 to 80?°C. The relative energies of activation calculated from the Arrhenius relationships of the 2-MAG acyl migration rate constants were 73.3, 68.0, and 72.9?kJ?mol?1 for the three 2-MAG species, respectively. Density functional calculations performed using the B3LYP functional at the 6-31+G* basis set on the three ketal ring intermediate of the three 2-MAG species followed a similar trend with a lack of relative energetic preference associated with the degree of desaturation. The kinetically determined relative activation energies were approximately twofold higher than the theoretical relative Gibbs free energies of the intermediates, suggesting that other factors influence acyl migration. In general, increasing desaturation after the C9 carbon of 2-MAG fatty acids had no appreciable effect on acyl migration rates. 相似文献
18.
N. S. Bhogal Manju Bala Sandeep Kumar J. Nanjundan Y. P. Singh 《Journal of the American Oil Chemists' Society》2014,91(3):463-470
The seed oils of 19 Indian mustard varieties were analyzed for fatty acid composition using GC–MS, reporting the presence of n-7 isomers of C18:1, C20:1 and C22:1 fatty acids. n-7 isomers namely cis-vaccenic (C18:1), 11, eicosenoic(C20:1) and 13-cis-docosenoic (C22:1) acids ranged from 0.61 to 1.73, 1.04 to 1.69 and 0.58 to 1.17 %, respectively. The average values of C20:1(n-7) was highest (1.36) amongst the three acids. Nervonic acid was also reported in the range of 0.69 to 2.52 %. The ratios of (n-7)/(n-9) ranged from 6.22 to 14.62, 12.38 to 27.35 and 2.01 to 3.24 % for C18:1, C20:1 and C22:1 fatty acids, respectively. The variety RLM-619 had the lowest elongation ratio (ER) as 0.44 and the highest desaturation ratio (DR) as 0.41 indicating higher efficiency of the desaturation pathway than for other varieties. The oleic desaturation ratio (ODR) values varied from 0.68 (Basanti) to 0.75 (GM-2) with a mean value of 0.72 and linoleic desaturation ratio from 0.40 (Basanti) to 0.49 (Pusa Bold) with a mean value of 0.45. Palmitoleic acid showed positive correlation with C18:1(n-7), C20:1(n-7), C20:2, C22:0, C22:1(n-7), C24:1, (n-7)/(n-9) ratio of C18:1 and C22:1 and a positive trend with ER but a significant negative correlation with C18:3, DR and ODR. The results indicated that palmitoleic acid is an important intermediate component in the synthesis of long chain (n-7) fatty acids. 相似文献
19.
《Food and Bioproducts Processing》2014,92(1):38-45
This research intends to verify the effect of Lactobacillus paracasei Fn032 fermentation and heat-moisture treatment (HMT) on the physicochemical properties of foxtail millet (Setaria italica) flour. The results obtained showed a significant (P < 0.05) increase in protein content (12.02–20.54%), total starch (15.78–51.01%) and starch fractions after fermentation and HMT. Differential scanning calorimetry (DSC) analysis showed high decomposition temperature (Td) trend of 180.59 and 189.82 °C after HMT. However, there was significant (P < 0.05) enthalpy (ΔH) decrease. Flour digestion resulted in variation of slow digestible starch (SDS) and resistant starch (RS) count from 6.83 to 18.42% and 7.61 to 22.68% respectively, after fermentation and HTM. Following this observation, it was ascertained that in X-ray diffraction; pasting viscosity and fluorescence spectrophotometry show greater HMT influenced on the flour components. Findings from the scanning electron microscopy (SEM) analysis showed microstructure differences of the flours samples. Fermentation and heat moisture treatment methods present a possible way of changing or improving the physicochemical properties and add nutritional value to foxtail millet meal. 相似文献
20.
S. L. Melton R. E. Movers J. T. Jaynes 《Journal of the American Oil Chemists' Society》1981,58(11):959-966
Three defatted soy flours (fully toasted, white and enzyme active) 92 days after production date were stored at 23 C for periods
of 0, 60, 120 and 180 days. At each storage period, lipoxygenase activity, thiobarbituric acid number (TBA), Nitrogen Solubility
Index (NSI) and total lipid were determined in 5 replications of each flour. The lipid was separated into 3 fractions by silicic
acid column chromatography and the fatty acid composition of each fraction was determined by GLC. Lipids in each fraction
were identified by TLC procedures. Toasted flour had the greatest amount of total lipid and lowest TBA of the flours and no
lipoxy-genase activity. Enzyme active soy flour had the highest NSI and the greatest lipoxygenase activity. During storage,
lipoxygenase activity of enzyme active flour and TBA and total lipid of each flour de-creased. Percentages of lipids in fraction
I, II or III were different among the soy flours, and the percentages of lipids in fractions I and II changed during storage.
In each lipid fraction during storage, linoleic acid decreased in toasted and white flours but remained constant in enzyme
active flour. Linoleic acid in any lipid fraction of enzyme active flour was lowest of the soy flours. 相似文献