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1.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361739

RESUMO

We developed an alternative whipping cream fat using shea butter but with low saturation. Enriched stearic-oleic-stearic (SOS) solid fat was obtained from shea butter via solvent fractionation. Acyl migration reactant, which mainly contains asymmetric SSO triacylglycerol (TAG), was prepared through enzymatic acyl migration to obtain the creaming quality derived from the ß'-crystal form. Through enzymatic acyl migration, we obtained a 3.4-fold higher content of saturated-saturated-unsaturated (SSU) TAG than saturated-unsaturated-saturated (SUS) TAG. The acyl migration reactant was refined to obtain refined acyl migration reactant (RAMR). An alternative fat product was prepared by blending RAMR and hydrogenated palm kernel oil (HPKO) at a ratio of 4:6 (w/w). The melting points, solid fat index (SFI), and melting curves of the alternative products were similar to those of commercial whipping cream fat. The alternative fat had a content of total unsaturated fatty acids 20% higher than that of HPKO. The atherogenic index (AI) of alternative fat was 3.61, much lower than those of whipping cream fat (14.59) and HPKO (1220.3), because of its low atherogenic fatty acid content and high total unsaturated fatty acids. The polymorphic crystal form determined by X-ray diffraction spectroscopy showed that the ß'-crystal form was predominant. Therefore, the alternative fat is comparable with whipping cream that requires creaming quality, and has a reduced saturated fat content.


Assuntos
Gorduras na Dieta/análise , Ácidos Graxos Insaturados/química , Tecnologia de Alimentos/métodos , Ácidos Oleicos/química , Óleos Vegetais/química , Fracionamento Químico , Cristalização , Ácidos Graxos Insaturados/análise , Humanos , Ácido Oleico/análise , Ácido Oleico/química , Ácidos Oleicos/análise , Óleo de Palmeira/análise , Óleo de Palmeira/química , Óleos Vegetais/análise , Ácidos Esteáricos/análise , Ácidos Esteáricos/química , Triglicerídeos/análise , Triglicerídeos/química
2.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205624

RESUMO

Studies have reported that cholesterol, a molecule found mainly in animals, is also present in some plants and algae. This study aimed to determine whether cholesterol exists in three dehydrated algae species, namely, Pyropia tenera, Saccharina japonica, and Undaria pinnatifida, and in one plant species, namely, Perilla frutescens (four perilla seed oil samples were analyzed). These species were chosen for investigation because they are common ingredients in East Asian cuisine. Gas chromatography-flame ionization detection (GC-FID) analysis found that cholesterol was present in P. tenera (14.6 mg/100 g) and in all four perilla seed oil samples (0.3-0.5 mg/100 g). High-performance liquid chromatography with evaporative light-scattering detection (HPLC-ELSD) also demonstrated that cholesterol was present in P. tenera (14.2 mg/100 g) and allowed the separation of cholesterol from its isomer lathosterol. However, cholesterol could not be detected by HPLC-ELSD in the perilla seed oil samples, most likely because it is only present in trace amounts. Moreover, liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmed the presence of cholesterol in both P. tenera and perilla seed oil. MRM results further suggested that lathosterol (a precursor of cholesterol) was present in P. tenera.


Assuntos
Perilla frutescens/metabolismo , Petróleo/metabolismo , Óleos Vegetais/metabolismo , Sementes/metabolismo , Ácido alfa-Linoleico/metabolismo , Colesterol/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos
3.
Molecules ; 26(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805759

RESUMO

Fat globule size and phospholipid (PL) content in human milk (HM) were investigated. HM was classified into three groups depending on fat content (A < B < C). PL content (mg/100 g HM) was significantly higher in the C group (p < 0.05), indicating its positive relationship with HM fat content. When the PL content was normalized (mg/g fat), that of group A was significantly higher (p < 0.05) and fat droplet size in group C was slightly larger, suggesting that HM fat content is affected by fat droplet numbers to a larger extent than by fat droplet size. A correlation between PC and SM content in HM was observed regardless of fat content, while correlation between PE and either PC or SM increased in the order of C > B > A, hence the composition and content of PL species in HM varied according to its fat content.


Assuntos
Gotículas Lipídicas/química , Gotículas Lipídicas/ultraestrutura , Leite Humano/química , Fosfolipídeos/química , Adulto , Animais , Feminino , Humanos , Lactente , Fórmulas Infantis/química , Lactação , Espectroscopia de Ressonância Magnética , Masculino , Leite/química , Tamanho da Partícula , Fosfolipídeos/análise , República da Coreia , Adulto Jovem
4.
Food Sci Biotechnol ; 29(3): 331-337, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32257516

RESUMO

In this study, a headspace gas chromatography (HS-GC) method was carried out to determine the contents of acetaldehyde, methanol and fusel oils in distilled liquors and sakès from different countries. A DB-Wax column was adopted in HS-GC, which showed good linearity, high precision and accuracy and low LOQ and LOD on all the compounds. Results showed that distilled liquors contained higher levels of acetaldehyde with the values of 12.88-35.53 mg/L than sakès (0.83-29.13 mg/L). Methanol was only detected in a few distilled liquors with small amounts. Amyl alcohols, including isoamyl alcohol (2-methyl-1-butanol) and active amyl alcohol (3-methyl-1-butanol), isobutanol (2-methyl-1-propanol) and 1-propanol were the main fusel oils among the distilled liquors and sakès analyzed. Amyl alcohols contents were 2 to 4 times higher in Korean distilled liquors (203.01-428.66 mg/L) than that in Chinese distilled liquors (28.52-42.77 mg/L) and all the sakès (61.90-166.59 mg/L).

5.
J Oleo Sci ; 69(2): 93-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023581

RESUMO

In this study, the antioxidative capacity of caffeic acid (CA), ascorbyl palmitate (AP), α-tocopherol (α-TO), and caffeic acid phenethyl ester (CAPE) was evaluated under the thermal oxidation model, in which 200 ppm of each compound was added to soybean oil, followed by thermal oxidation at 180°C for 32 h. Change of viscosity, acid value (AV), conjugated dienoic acid value (CDAV), p-anisidine value (p-AV), total polar materials (TPM), and the ratio of C18:2 to C16:0 (LA/PA) were evaluated during the reaction. All antioxidants showed significantly lower viscosity, TPM, and p-AV, and higher LA/PA, than the control (without antioxidant, CON), indicating that thermal oxidation was delayed. Among them, CAPE showed significantly lower viscosity, TPM, and p-AV, and higher LA/PA, than the other antioxidants (p < 0.05). In the correlation between the oxidation parameters measured from CON and CAPE, the correlation coefficient between p-AV and viscosity was rather low at r = 0.7603 (in CON) and r = 0.7338 (in CAPE), respectively.


Assuntos
Ácido Ascórbico/análogos & derivados , Ácidos Cafeicos/química , Ésteres/química , alfa-Tocoferol/química , Ácido Ascórbico/química , Oxirredução
6.
Food Sci Biotechnol ; 28(6): 1649-1658, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807337

RESUMO

An effective evaluation model was established to digitize the quality of cocoa butter equivalents (CBEs) based on determinations of total and sn-2 fatty acid compositions and triacylglycerol (TAG) profiles and the "deducting score" principle. Similarity scores for selected fats and oils calculated from the model revealed differences between them and parallel cocoa butter compositions. For CBE1 and CBE2, total similarity scores were 90.6 and 90.0, whereas those of mango (76.3), dhupa (84.1), sal fat (84.7), kokum (78.3), palm mid fractions (PMF, 77.9), shea butter (64.0), illipe butter (89.7) and Pentadesma butyracea butter (67.2), respectively. Similarity scores were found to agree with physical properties, including polymorphism, crystal morphology, crystallization or melting behaviors, and solid fat content. The present study provides an accurate means of assessing CBE quality and hopefully will contribute to the development of commercial CBEs.

7.
Nutrients ; 11(9)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484355

RESUMO

Thirty-four samples of human milk (HM) collected from mothers in Korea were classified into three groups according to their fat content. The lutein + zeaxanthin, ß-cryptoxanthin, ß-carotene, lycopene, α-carotene, and fatty acids (FAs) present in the HM were quantitatively analyzed. Lutein + zeaxanthin and ß-cryptoxanthin were the most abundant carotenoid components in this study, followed by ß-carotene. When the classified groups were compared in terms of the content of each carotenoid, there was no statistical difference (p > 0.05), indicating that there is no correlation between the content of fat and carotenoid in HM. The mean content of saturated FAs (SFAs), monounsaturated FAs, and polyunsaturated FAs in the analyzed HM were 1.46, 1.36, and 0.83 g/100 g, respectively. In addition, the mean content of arachidonic acid (AA) and docosahexaenoic acid (DHA) were 0.02 and 0.029 g/100 g, respectively. Alternatively, all FAs except for certain SFAs (i.e., C8:0, C10:0, C12:0, and C14:0) did not show statistical difference in composition among the three groups (p > 0.05), indicating that the differences in the fat content of HM have limited influence on the FA composition of HM.


Assuntos
Carotenoides/química , Gorduras/química , Ácidos Graxos/química , Leite Humano/química , Carotenoides/metabolismo , Humanos , República da Coreia
8.
Molecules ; 24(14)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31311184

RESUMO

Herein, contaminants remaining in distillate and distillers' stillage were quantitatively measured after distillation. After rice bran powder was contaminated with 10 ppm of lead (Pb) and cadmium (Cd) or 0.02-1.27 ppm of five pesticides (terbufos, fenthion, iprobenfos, flutolanil, and ethoprophos) followed by fermentation, single-stage distillation was performed. In the obtained distillate, no Pb or Cd was found, as expected. However, when the pesticides were added as contaminants, trace-0.05 ppm of some pesticides were detected in the distillate, possibly due to the high vapor pressure (e.g., that of ethoprophos) and contamination amount (e.g., that of flutolanil, terbufos, and fenthion). In contrast, none of the contaminating pesticides were observed in the distilled spirits when a fermented liquefaction contaminated with 0.04-4 ppm of six pesticides (fenthion, terbufos, ethoprophos, iprobenfos, oxadiazon, and flutolanil) was distilled using a pilot-plant scale distillation column, indicating that the pesticides hardly migrate to the distilled spirits.


Assuntos
Bebidas Alcoólicas/análise , Contaminação de Alimentos/análise , Oryza/química , Resíduos de Praguicidas/análise , Anilidas/análise , Cádmio/análise , Destilação , Fention/análise , Fermentação , Chumbo/análise , Compostos Organotiofosforados/análise , Projetos Piloto
9.
Food Sci Biotechnol ; 28(1): 35-41, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30815292

RESUMO

The product of ferulic acid decarboxylation, 4-vinylguaiacol (4-VG), is an important antioxidant and is reported to have an antioxidant capacity comparable to α-tocopherol. In this study, evaluation on antioxidant capacities of ferulic acid, catechin, and 4-VG was performed when 200 ppm of each compound was added in a 10% O/W emulsion for 50 days. Peroxide value (POV) results of the O/W emulsion containing 4-VG were noteworthy. The POV was 1.9 meq/L of emulsion after 29 days, which was no different to the initial value (day 0). Even when the oxidation was allowed to advance to day 50, the POV remained at 2.2 meq/L of emulsion, representing only a tiny increase relative to the initial value on day 0. 1H-NMR results also showed that the lowest conjugated forms and no aldehydes were detected in emulsion of 4-VG stored for 50 days, proving the excellent antioxidant capacity in the O/W emulsion.

10.
Nutrients ; 11(3)2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30901932

RESUMO

In this study, two in vitro digestion models were employed to compare the rate of lipolysis in soybean oil (SBO), pomegranate oil (PGO), a physical blend (PHY, 1:1 molar ratio of SBO:PGO, w/w), and their enzymatically interesterified oil (IO). In the pH-stat digestion model (emulsified oils with bile salts), PGO emulsion containing 74.7% conjugated form of linolenic acid (CLn) showed a significantly lower release rate of free fatty acid (FFA) than the other oil emulsions (p < 0.05). In FFA release rates and oil droplet sizes between PHY and IO emulsions, no significant differences were observed (p > 0.05). In a simulated model of small intestinal digestion, the lipolysis rates of SBO, PGO, PHY, and IO after digestion for 30 min in digestion fluids were 80.4%, 66.5%, 74.8%, and 77.0%, respectively. The rate of lipolysis in PGO was significantly lower than that in SBO (p < 0.05), and the lowest lipolysis rate was observed in the conjugated form of trilinolenoyl glycerol (CLn-CLn-CLn).


Assuntos
Ácidos Graxos/farmacologia , Lipólise/efeitos dos fármacos , Lythraceae , Óleos Vegetais/farmacologia , Óleo de Soja/farmacologia , Ácidos e Sais Biliares , Digestão/efeitos dos fármacos , Emulsões/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Intestino Delgado/metabolismo , Modelos Biológicos , Ácido alfa-Linoleico
11.
Food Chem ; 275: 739-745, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724257

RESUMO

Palm mid-fraction (PMF), which has a high content of symmetric POP, was converted to asymmetric PPO (APMF) via acyl migration. After solvent fractionation, the liquid phase of acyl migrated PMF (APMF-L) was obtained and blended with hydrogenated coconut oil (HCO, 50:50, w/w) to produce a fat blend (namely, an alternative fat blend) which had reduced saturated fatty acid content while having similar melting behavior to HCO. In an alternative fat blend, the major fatty acids were lauric (27.94), palmitic (26.93) and oleic (15.75 mol%) acid. The solid fat index was quite similar to that of HCO, especially at 28-44 °C. Nevertheless, an alternative fat blend had lower saturated fatty acid content, by 18%, compared to HCO. The content of highly atherogenic myristic acid was reduced by approximately 40%. The alternative fat blend in this study could be used as a raw material for non-dairy cream with low saturated fat content.


Assuntos
Cromatografia Gasosa , Óleo de Coco/química , Ácidos Graxos/análise , Varredura Diferencial de Calorimetria , Óleo de Coco/metabolismo , Emulsões/química , Hidrogenação , Ácidos Láuricos/análise , Ácido Oleico/análise , Ácido Palmítico/análise , Óleos Vegetais/química , Óleos Vegetais/metabolismo
12.
Food Sci Biotechnol ; 27(4): 1041-1046, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30263833

RESUMO

Decarboxylation of ferulic acid would increase the solubility in oils. Rice bran extract (RBE) containing 29 mg ferulic acid/g RBE was decarboxylated to obtain decarboxylated rice bran extract (DRBE), and its antioxidant capacity in oil system was studied. After addition of DRBE (500 ppm), oxidation was monitored for 20 days at 60 °C under the dark. To compare the oxidation degree, 500 ppm of ferulic acid and well-known lipid soluble antioxidant, α-tocopherol, were used. Contents of conjugated dienes and aldehydes were measured using 1H NMR as well as peroxide value (POV). On 7 days of oxidation, DRBE (539.0 meq/kg oil) showed lower POV than the control (819.7 meq/kg oil). Also, contents of total conjugated form and aldehydes were 194.60, and 5.94 mmol/L oil, which were lower than those of control (323.63 and 15.94 mmol/L oil). However, after 10 days of oxidation, antioxidant capacity of DRBE was not observed.

13.
PLoS One ; 12(5): e0176037, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28459863

RESUMO

The present investigation was conducted to study the true retentions of α-tocopherol, tocotrienols and ß-carotene in crown daisy, unripe hot pepper, onion, garlic, and red pepper as affected by various domestic cooking methods, those were, boiling, baking, stir-frying, deep-frying, steaming, roasting, and microwaving. Fatty acid compositions were determined by GC, and HPLC were used for quantification of α-tocopherol, tocotrienols, and ß-carotene. True retentions of α-tocopherol in cooked foods were as follows: boiling (77.74-242.73%), baking (85.99-212.39%), stir-frying (83.12-957.08%), deep-frying (162.48-4214.53%), steaming (45.97-179.57%), roasting (49.65-253.69%), and microwaving (44.67-230.13%). Similarly for true retention of ß-carotene were: boiling (65.69-313.75%), baking (71.46-330.16%), stir-frying (89.62-362.46%), deep-frying (178.22-529.16%), steaming (50.39-240.92%), roasting (73.54-361.47%), and microwaving (78.60-339.87%).


Assuntos
Culinária , Especiarias/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Culinária/métodos , Ácidos Graxos/química , Temperatura Alta , Micro-Ondas , Tocotrienóis/química , Água/química , alfa-Tocoferol/química , beta Caroteno/química
14.
Food Sci Biotechnol ; 26(2): 349-355, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263549

RESUMO

This study was conducted to compare the organic acid content in liquors (red wine, white wine, and beer) using three different high-performance liquid chromatography analysis methods. Post-column reaction methods (method 2 and 3) were found to be more promising than UV-detection method (method 1). Using method 2 (two columns), the analyzed red wine was found to contain 2,652.4 mg/L tartaric acid and 1,392.9 mg/L lactic acid but relatively lower amounts of malic acid (271.0 mg/L). Furthermore, tartaric acid (1,160.8-2,749.1 mg/L) and malic acid (470.2-3,107.9 mg/L) were the major components in white wine. Beers were analyzed using method 3 (one column). In the analyzed foreign beers, lactic acid (95.9-226.4 mg/L), malic acid (62.2-110.5 mg/L), acetic acid (93.5-183.8 mg/L), and succinic acid (37.0-56.2 mg/L) were detected. Similar to the foreign beers, the contents of succinic acid in the domestic beers were the lowest. The proposed methods could be useful for quantitative analysis of organic acids in wine and beer.

15.
Food Sci Biotechnol ; 26(4): 893-899, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263617

RESUMO

Diacetyl is a natural fermentation by-product and is an important flavor component of certain liquors. This paper aims to validate the high performance liquid chromatography (HPLC) method based on derivatization with 1,2-diaminobenzene for diacetyl quantification in liquor samples. A limit of quantitation of 0.039 mg/L was obtained. Coefficient regression (R2) of calibration curve for the HPLC-UV method exceeded 0.999, showing adequate linearity on the standard curve. Relative standard deviation values obtained from intraday and interday analysis for precision were 2.5 and 4.1%, respectively. Using the validated method, the contents of diacetyl in liquors (12 types, 389 samples) distributed throughout Korea were monitored. The average diacetyl content of all analyzed liquor samples ranged from trace amounts to 3.655 mg/L (microbrewery beer). The highest average diacetyl content was found in fruit wines (0.432 mg/L), followed by red wine (0.320 mg/L) and general distilled spirits (0.249 mg/L). In takju and yakju, no distinctive effect of sterilization on diacetyl content was found.

16.
J Food Sci ; 81(10): C2373-C2380, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27627797

RESUMO

The sn-1,3-regiospecific Rhizomucor miehei lipase (Lipozyme RM IM) was employed to produce structured diacylglycerol (SL-DAG), which contained 67.3 mol% DAG with 27.2 area% of C18:3. To investigate the oxidative stability of the SL-DAG in emulsion form, 5% oil-in-water (O/W) emulsions were prepared with 200 and 400 ppm sinapic acid. It was shown that the hydroperoxide values of the control (without any antioxidant) was the highest (117.7 meq/L) on day 43 of storage and thereafter the value decreased. However, the emulsions with 200 and 400 ppm sinapic acid resulted in slow oxidation degree until day 64 of storage (30.3 and 7.3 meq/L, respectively). Aldehyde measurements for the 200 ppm sinapic acid emulsion (12.8 mmol/mol) and the 400 ppm sinapic acid emulsion (7.5 mmol/mol) also showed better oxidative stability than that for the 200 ppm catechin emulsion (27.4 mmol/mol) and the control (52.7 mmol/mol). Although the SL-DAG in the emulsions contains high levels of polyunsaturated fatty acids, the degree of oxidation in the emulsions can be reduced when sinapic acid is used as an antioxidant.


Assuntos
Antioxidantes/farmacologia , Ácidos Cumáricos/farmacologia , Diglicerídeos/metabolismo , Emulsões , Peroxidação de Lipídeos , Extratos Vegetais/farmacologia , Ácido alfa-Linoleico/metabolismo , Brassica rapa/química , Catequina/farmacologia , Diglicerídeos/biossíntese , Humanos , Peróxido de Hidrogênio/metabolismo , Lipase/metabolismo , Oxirredução , Rhizomucor/enzimologia , Água
17.
Food Sci Biotechnol ; 25(4): 955-963, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30263360

RESUMO

In the present study, the ß-carotene contents of 14 plant food materials prepared by boiling, steaming, or baking or when they are raw were analyzed and compared. After boiling three pulse species, namely, peas, kidney beans, and dried mung beans, ß-carotene contents of peas and kidney beans increased significantly, whereas that of mung beans (dried material) decreased. True retention factors of ß-carotene contents in the cooked kidney beans, peas, and mung beans after boiling were 174.2, 128.3, and 91.8%, respectively. After steaming, the ß-carotene content of regular millets significantly decreased but that of taros increased, in which the true retention factors were observed with ß-carotene contents of 72.4% in the steamed regular millets and 160.9% in the steamed taros. Moreover, ß-carotene contents in yellow-fleshed sweet potato (raw: 896.2 µg/100 g) decreased by baking (786.4 µg/100 g) and steaming (steaming: 553.1 µg/100 g). These results suggest that ß-carotene contents in the selected plant food materials markedly depend on the cooking method and plant food materials classification.

18.
J Food Sci ; 81(1): C35-41, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26641978

RESUMO

Caffeic acid was used to synthesize 4-vinylcatechol (4-VC) by thermal decarboxylation and to prepare caffeic acid phenethyl ester (CAPE) by esterification reaction. The identities of synthesized products were confirmed by (1)H NMR. Antioxidative activities of 4-VC and CAPE were compared with α-tocopherol and BHT in stripped soybean oil at 60 °C under the dark. To evaluate the degrees of oxidation at different concentrations and combinations, peroxide value (PV) and (1)H NMR were performed. From the results of PV, the formation of primary oxidation products (i.e., hydroperoxides) in stripped soybean oil containing 200 ppm CAPE was the slowest. The relative oxidation degree of 200 ppm CAPE (9.5%) was lower than other samples on 9 d. Similar results were obtained by (1)H NMR analysis. After 15 d of storage, levels of conjugated diene forms and aldehydes of 200 ppm CAPE sample (57.3 and 0.9 mmol/mol oil) were also lower than other treatments. In addition, 4-VC and α-tocopherol were found to have a synergistic antioxidant effect.


Assuntos
Antioxidantes/química , Ácidos Cafeicos/química , Catecóis/química , Álcool Feniletílico/análogos & derivados , Óleo de Soja/química , Peróxido de Hidrogênio/química , Oxirredução , Peróxidos/química , Álcool Feniletílico/química , alfa-Tocoferol/análise
19.
J Agric Food Chem ; 63(47): 10280-6, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26492097

RESUMO

Caffeic acid phenethyl ester (CAPE) and 4-vinylcatechol (4-VC) were prepared for studying their antioxidative activities in emulsion. Oil-in-water emulsions of stripped soybean oil containing 200 ppm of CAPE, 4-VC, or α-tocopherol were stored at 40 °C in the dark for 50 days, and proton nuclear magnetic resonance ((1)H NMR) was used to identify and quantify the oxidation products. Emulsion droplet sizes, peroxide values, and levels of primary oxidation products (i.e., hydroperoxides) and secondary oxidation products (i.e., aldehydes) were determined. The results showed that CAPE (200 ppm) and 4-VC (200 ppm) had significantly greater antioxidant activities on the oxidation of stripped soybean oil-in-water emulsions than α-tocopherol (200 ppm). The peroxide values of CAPE (8.4 mequiv/L emulsion) and 4-VC (15.0 mequiv/L emulsion) were significantly lower than that of α-tocopherol (33.4 mequiv/L emulsion) (p < 0.05) on 36 days. In addition, the combinations of CAPE + α-tocopherol (100 + 100 ppm) or 4-VC + α-tocopherol (100 + 100 ppm) had better antioxidant activities than α-tocopherol (200 ppm). For CAPE + α-tocopherol, 4-VC + α-tocopherol, and α-tocopherol, the amounts of conjugated diene forms were 16.67, 13.72, and 16.32 mmol/L emulsion, and the concentrations of aldehydes were 2.15, 1.13, and 4.26 mmol/L emulsion, respectively, after 50 days of storage.


Assuntos
Ácidos Cafeicos/química , Catecóis/química , Álcool Feniletílico/análogos & derivados , Óleo de Soja/química , Antioxidantes/química , Emulsões/química , Estrutura Molecular , Oxirredução , Álcool Feniletílico/química
20.
J Food Sci ; 80(3): C510-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25678328

RESUMO

To compare the oxidative stability between diacylglycerol (DAG) oil and conventional triacylglycerol (TAG) oil (that is, soybean oil), the prepared stripped diacylglycerol oil (SDO) and soybean oil (SSBO) were stored at 60 °C in the dark for 144 h. During storage peroxide values (POVs), contents of aldehydes, unsaturated fatty acids were measured to evaluate the oxidative stabilities of the 2 oils. The results showed the content of C18:2, C18:3, and total unsaturated fatty acid decreased faster in DAG oil than in soybean oil, whereas the decreased rate of C18:1 was similar in 2 oils. Also, both rate constants (K1 and K2) obtained from POV (K1 ) and total aldehydes (K2 ) indicated that DAG oil (K1 = 3.22 mmol/mol FA h(-1) , K2 = 0.023 h(-1)) was oxidized more rapidly than soybean oil (K1 = 2.56 mmol/mol FA h(-1) , K2 = 0.021 h(-1)), which was mainly due to the difference of acylglycerol composition of the 2 oils along with higher C18:3 (9.6%) in SDO than SSBO (5.7%). It is concluded that DAG was more easily oxidized than soybean oil at 60 °C in the dark for 144 h.


Assuntos
Diglicerídeos/análise , Peroxidação de Lipídeos , Óleos/análise , Óleo de Soja/análise , Triglicerídeos/análise , Dieta , Glicerídeos/análise , Humanos , Oxirredução
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