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1.
J Sci Food Agric ; 102(14): 6668-6675, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35608931

RESUMO

BACKGROUND: Enzyme-modified butter is used as a common raw material to obtain a natural milk flavor. Butter protein is a by-product in butter processing that can be used as substrate to produce taste-active peptides, which can create additional value and new application opportunities, making the method more environmentally friendly. RESULTS: Putative kokumi peptides from hydrolysates of protein by-products were isolated by gel filtration chromatography and reversed-phase high-performance liquid chromatography. The isolated peptide fraction with the most pronounced kokumi taste was screened by sensory evaluation and electronic tongue analysis. Eleven peptides were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Six peptides were synthesized to verify their taste characteristics. Five synthetic peptides (FTKK, CKEVVRNANE, EELNVPG, VPNSAEER and YPVEPFTER) showed different intensity levels of kokumi taste. Of these peptides, the decapeptide CKEVVRNANE had the highest kokumi intensity. CONCLUSION: The newly identified kokumi peptides increased the kokumi taste intensity and showed some synergistic effect with umami taste. Both termini of the peptides seem to play an important role in taste characteristic. Glu residue at both termini can increase the kokumi taste intensity. This work indicated that it was feasible to produce kokumi peptides by enzymatic hydrolysis of the protein by-products of butter. © 2022 Society of Chemical Industry.


Assuntos
Manteiga , Peptídeos , Manteiga/análise , Cromatografia em Gel , Nariz Eletrônico , Peptídeos/química , Paladar
2.
J Agric Food Chem ; 70(18): 5756-5763, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35482605

RESUMO

We quantified the enantiomeric distributions of δ- and γ-lactones in butter, fermented butter, and margarine through the combination of solvent extraction and enantioselective gas chromatography-mass spectrometry. The main lactones in butter and fermented butter comprised (R)-δ-decalactone, (R)-δ-dodecalactone, (R)-δ-tetradecalactone, (R)-δ-hexadecalactone, and (R)-γ-dodecalactone. In contrast, margarine samples consisted of only δ-decalactone and δ-dodecalactone in racemic forms, indicating that synthetic aroma chemicals were added to margarine. After heat treatment, 13 types of lactones were detected in butter and fermented butter. In heated butter and fermented butter, major δ-lactones in the (R)-form were abundant, but only δ-octalactone in the (S)-form was detected. In contrast, γ-dodecalactone (main γ-lactone in the heated samples) was abundant in the (R)-form, whereas other γ-lactones were detected in the racemic form. These results suggested that the major lactones in dairy products are in the (R)-form. Furthermore, the heat treatment affected the enantiomeric distribution of lactones in butter and fermented butter.


Assuntos
Manteiga , Margarina , Manteiga/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lactonas/química , Margarina/análise , Solventes/análise , Estereoisomerismo
3.
J Chromatogr A ; 1642: 462025, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33721815

RESUMO

In this study, an elevated temperature liquid-liquid extraction combined method with successive air-assisted liquid-liquid microextraction has been proposed for the extraction of four phytosterols in cow milk butter and animal oil samples prior to gas chromatography-flame ionization detector. The method is started by combining a few grams of the melted butter or oil samples with ethanol. The mixture is vortexed and placed into a water-bath adjusted at 50 °C. After a few minutes, the mixture is allowed to cool at room temperature. In this step, the butter or oil is become stiff and ethanol is collected on top of the sample. The separated ethanol phase is collected and mixed with deionized water to obtain a homogenous solution. After that, a few microliters of ethyl methyl ammonium chloride: pivalic acid deep eutectic solvent is added into the solution and the mixture was pulled into a glass test tube and pushed back to the tube for five times. After centrifugation, whole of the collected phase at the bottom of tube was withdrawn and transferred into a microtube and contacted with sodium hydroxide solution. The mixture is withdrawn and released to the tube 2 times to remove the extracted fatty acids. The validation data verified that high enrichment factors (385-450) and extraction recoveries (77-90%), low limits of quantification (2.6-5.2 ng g-1) and detection (0.73-1.5 ng g-1), and satisfactory relative standard deviations (≤ 9.3%) can be obtained with this method. At last, the developed method was successfully used for the analysis of phytosterols in various butter and oil samples marketed in Tabriz, Iran.


Assuntos
Ar , Manteiga/análise , Microextração em Fase Líquida/métodos , Óleos/análise , Fitosteróis/análise , Animais , Cromatografia Gasosa , Ácidos Graxos/análise , Leite/química , Reprodutibilidade dos Testes , Solventes/análise , Temperatura , Fatores de Tempo , Água/análise
4.
J Food Sci ; 85(10): 3072-3080, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32869333

RESUMO

The addition of different amounts of a functional ingredient composed of water, inulin, chia seeds, and hemp or flaxseed oil was examined as butter replacer to improve the nutritional value of muffins. Nutritional, technological, and sensory characteristics of the reformulated products were assessed, as well as the stability under storage at room temperature. One control and six modified formulations with three levels of butter replacement (50%, 75%, and 100%) were analyzed. Modified muffins improved their nutritional profile, reducing up to 78% of fat and increasing fiber (up to 62.5%) and omega-3 fatty acids content (from 0.12 g/100 g of product to 0.62 g and 1.55 g in hemp and flaxseed oil samples, respectively). Sensory analysis revealed that flaxseed oil samples were indistinguishable from the control in all evaluated attributes, even in the highest level of replacement. During storage, texture of modified samples behaved similar to the control and no oxidation problems were observed in any of the formulations. Therefore, the functional ingredient proved to be a feasible alternative for replacing butter in muffins, preserving the quality attributes and making them healthier foods. PRACTICAL APPLICATION: Functional ingredients including fiber and low amounts of good-quality sources of fat have a simple manufacturing process, do not require heating, and perform well once incorporated to the matrix. They are versatile and could be incorporated in other bakery products to substitute butter or even oil, to obtain a reduced calorie product and with an enhanced nutritional profile and good sensory properties.


Assuntos
Cannabis/química , Substitutos da Gordura/análise , Linho/química , Inulina/análise , Óleos de Plantas/análise , Salvia/química , Pão/análise , Manteiga/análise , Fibras na Dieta/análise , Aditivos Alimentares/análise , Manipulação de Alimentos , Humanos , Valor Nutritivo , Oxirredução , Sementes/química , Paladar
5.
J Food Sci ; 85(8): 2461-2469, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32671855

RESUMO

Oleogels were prepared by emulsion template method through 3.0% tea polyphenol ester (Tp-ester) particles with four fatty acid chain length (Tp-laurate [C12], Tp-myristate [C14], Tp-palmitate [C16], and Tp-stearate [C18]) and 2.5% citrus pectin, and then were used in cookie production as fat replacer. Effects of the fatty acid chain length on the hydrophilicity/hydrophobicity of Tp-ester, on the appearance, microstructure, and firmness of dried products, on rheological features of oleogels, on the dynamic viscoelasticity and textural characteristics of cookies dough, and on cookies qualities were revealed. With the increase in the fatty acid chain length, the θo and θw values of four Tp-esters increased, the firmness of dried products with smaller oil droplets got larger, and the gel intensity of oleogels increased, but the quality scores, spread ratio, and break strength of the cookies did not change significantly. With the increase in the replacement levels of butter with oleogels, the harder cookie dough with weaker gel strength and the softer cookies with lower hedonic scores and crispness were found. At 25% and 50% replacement levels, cookies prepared with oleogels using Tp-palmitate or Tp-stearate particles exhibited similar hedonic scores, break strength, spread ratio, and storage stabilities to that of butter cookies. PRACTICAL APPLICATION: Cookies are relished by all age groups due to their taste and crispness, but include high content of saturated fatty acids that are harmful to people's health. The result of this study will help the industry to better design cookies through oleogels with tea polyphenols ester and pectin, and will provide healthy cookies with little or no butter for consumers.


Assuntos
Ésteres/química , Ácidos Graxos/química , Óleos de Plantas/química , Polifenóis/química , Manteiga/análise , Camellia/química , Emulsões/química , Farinha/análise , Manipulação de Alimentos , Dureza , Humanos , Compostos Orgânicos/química , Reologia , Triticum/química , Viscosidade
6.
J Agric Food Chem ; 68(17): 4973-4980, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32298092

RESUMO

Fatty acid analysis of food lipids containing branched chain fatty acids (BCFAs) are complex because of unavoidable gas chromatography (GC) co-elution. We demonstrate a method for convenient quantitative GC coupled to novel solvent-mediated chemical ionization (CI) mass spectrometry (MS) that enables resolution of co-eluting peaks by mass. The relevant masses yield uniform responses for C14-20 normal fatty acids and BCFAs, eliminating the need for rare purified BCFA standards essential for unpredictable responses, as for electron ionization (EI). CI-tandem mass spectrometry analysis of MH+ yields fragments characteristic of the branch position. Application of the measurement to BCFAs in salami samples demonstrates consistent results for the novel method and EI-MS. A higher proportion of C17-18 BCFAs was found in beef compared to milkfat, possibly indicative of fatty acid elongation, endogenous in the beef animal. This method enables straightforward structure elucidation and quantification of food BCFAs and similar chain length normal fatty acids without purified standards.


Assuntos
Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Animais , Manteiga/análise , Bovinos , Ácidos Graxos/metabolismo , Análise de Alimentos , Carne/análise
7.
Lipids Health Dis ; 19(1): 10, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31948460

RESUMO

BACKGROUND: Ω-3 fatty acids perform several therapeutic functions in the body, however, their applications are limited due to the inferior oxidative stability. To improve the oxidative stability and release properties of Ω-3 fatty acids, microencapsulation is performed. Butter is a good source of fat-soluble vitamins and antioxidant systems however, it is not a good source of Ω-3 fatty acids. Supplementation of butter with microcapsules of vegetable oils rich in Ω-3 fatty acids is not reported in literature. METHODS: Microcapsules of chia oil (MCO) were prepared using chitosan as encapsulating material by spray drying at lower temperature. Unsalted butter prepared from cultured cream using Lactococcus lactis ssp. Lactis at 21 °C for 16 Hrs. Cream was churned at 12 °C and microcapsules of chia oil were added to the butter during the working stage at four different concentrations i.e. 2, 4, 6 and 8% (T1, T2, T3 and T4, respectively). Butter without supplementation of MCO were kept as control. Butter samples were stored for 90 days at -10 °C. Butter composition, antioxidant capacity, fatty acid profile, induction period, free fatty acids, peroxide value and sensory evaluation were performed at 0, 45 and 90 days of storage. RESULTS: Addition of MCO in butter did not have any effect on standards of identity of butter. Microencapsulation had no effect on fatty acid profile of microcapsules of chia oil. Concentration of alpha-linolenic acid (ALA) in control, T1, T2, T3 and T4 were 0.49, 4.29, 8.41, 13.21 and 17.44%, respectively. Concentration of ALA in fresh and 90 days stored butter samples were 17.44 and 17.11%, respectively. After 90 days of storage, loss of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were 0.07%, 0.05 and 0.03%, respectively. At 0, 45 and 90 days of storage, 2, 2-Diphenyl-1-picrylhydrazyle (DPPH) free radical scavenging activity of free chia oil was 39.81, 71.22 and 62.18%, respectively. However, microcapsules of chia oil had superior antioxidant activity. DPPH free radical scavenging activity of microcapsules at 0, 45 and 90 days of storage was 36.51, 36.43 and 35.96%, respectively (p > 0.05). Total antioxidant capacity of microcapsules at 0, 45 and 90 days of storage was 70.53, 69.88 and 68.52%, respectively (p > 0.05). It was recorded that induction period of free chia oil and microcapsules was only 2.86 h and 8.55 h. Among the butter samples, control revealed the lowest induction period. While, induction period of experimental samples was not different from each other. Peroxide value and free fatty acids of the butter samples at the end of storage period (90 days) was less than the European Union standards limit (10MeqO2/kg and 0.2%). Sensory characteristics of experimental samples were similar to the control. MCO can be added in butter to improve its functional value. CONCLUSION: Concentration of Ω-3 fatty acids in butter up to 8% can be increased through microcapsules of chia oil with reasonable oxidative stability and no effect on sensory characteristics.


Assuntos
Antioxidantes/química , Medicamentos de Ervas Chinesas/farmacologia , Ácidos Graxos Ômega-3/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/farmacologia , Manteiga/análise , Canfanos , Cápsulas/química , Cápsulas/farmacologia , Quitosana/química , Medicamentos de Ervas Chinesas/química , Ácidos Graxos Ômega-3/química , Humanos , Lactococcus lactis/metabolismo , Oxirredução/efeitos dos fármacos , Panax notoginseng , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Salvia/química , Salvia miltiorrhiza
8.
Toxins (Basel) ; 11(6)2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159287

RESUMO

Mycotoxins are secondary metabolites, produced by fungi of genera Aspergillus, Penicillium and Fusarium (among others), which produce adverse health effects on humans and animals (carcinogenic, teratogenic and immunosuppressive). In addition, mycotoxins negatively affect the productive parameters of livestock (e.g., weight, food consumption, and food conversion). Epidemiological studies are considered necessary to assist stakeholders with the process of decision-making regarding the control of mycotoxins in processing environments. This study addressed the prevalence in feed ingredients and compound feed of eight different types of toxins, including metabolites produced by Fusarium spp. (Deoxynivalenol/3-acetyldeoxynivalenol, T-2/HT-2 toxins, zearalenone and fumonisins) and two additional toxins (i.e., ochratoxin A (OTA) and aflatoxin M1 (AFM1)) from different fungal species, for over a period of five years. On the subject of Fusarium toxins, higher prevalences were observed for fumonisins (n = 80/113, 70.8%) and DON (n = 212/363, 58.4%), whereas, for OTA, a prevalence of 40.56% was found (n = 146/360). In the case of raw material, mycotoxin contamination exceeding recommended values were observed in cornmeal for HT-2 toxin (n = 3/24, 12.5%), T-2 toxin (n = 3/61, 4.9%), and ZEA (n = 2/45, 4.4%). In contrast, many compound feed samples exceeded recommended values; in dairy cattle feed toxins such as DON (n = 5/147, 3.4%), ZEA (n = 6/150, 4.0%), T-2 toxin (n = 10/171, 5.9%), and HT-2 toxin (n = 13/132, 9.8%) were observed in high amounts. OTA was the most common compound accompanying Fusarium toxins (i.e., 16.67% of co-occurrence with ZEA). This study also provided epidemiological data for AFM1 in liquid milk. The outcomes unveiled a high prevalence of contamination (i.e., 29.6-71.1%) and several samples exceeding the regulatory threshold. Statistical analysis exposed no significant climate effect connected to the prevalence of diverse types of mycotoxins.


Assuntos
Ração Animal/análise , Manteiga/análise , Contaminação de Alimentos/análise , Leite/química , Micotoxinas/análise , Animais , Búfalos , Costa Rica , Cadeia Alimentar , Fusarium
9.
Hig. Aliment. (Online) ; 33(288/289): 847-851, abr.-maio 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482055

RESUMO

A manteiga de garrafa é um produto de cunho regional e cultural do norte mineiro e nordeste do país, onde é ofertada em feiras de comércio livre, sem embalagem adequada e rotulagem, dado que é um produto lipídico, a sua exposição a luz, sujeita o produto a reação de oxidação, que reduz o tempo de vida útil. Em decorrência deste fato o presente trabalho utilizou a análise discriminante, como ferramenta para enquadrar dados físico-químicos de manteigas de garrafa, acerca dos tempos de 30, 60 e 90 dias corridos de armazenagem, objetivando predizer o prazo em que o produto foi obtido. O método estatístico apontou como variáveis de maior impacto, ao decorrer do tempo, sendo a turbidez e o ponto de fusão da amostra e mostrou-se eficaz na separação dos períodos de estocagem avaliados, permitindo predizer o tempo de armazenamento das amostras.


Assuntos
Análise Discriminante , Armazenamento de Alimentos/estatística & dados numéricos , Manteiga/análise , Manteiga/estatística & dados numéricos , Fatores de Tempo , Fenômenos Químicos
10.
Hig. Aliment. (Online) ; 33(288/289): 867-872, abr.-maio 2019. graf, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482059

RESUMO

A manteiga de garrafa, também conhecida como manteiga da terra, é um produto abundante em gordura anidra, sendo assim está susceptível as reações de deterioração conhecidas como rancidez, tanto hidrolítica quanto oxidativa, responsáveis por alterações sensoriais indesejáveis, o que diminuem a qualidade nutricional e geram impacto econômico para os produtores. Diante disso, o objetivo deste trabalho foi identificar os produtos de acordo com o seu estágio de deterioração, quanto aos aspectos físico-químicos: pH, umidade, turbidez, condutividade, concentração de sólidos, ponto de fusão, índice de acidez e peróxido, utilizando a análise de componentes principais (ACP), para a interpretação dos dados. O modelo estatístico se mostrou eficiente na separação em grupos das amostras de manteiga com armazenamento de 30, 60 e 90 dias.


Assuntos
Contaminação de Alimentos , Fenômenos Químicos , Manteiga/análise , Manteiga/estatística & dados numéricos , Análise de Componente Principal
11.
Hig. Aliment. (Online) ; 33(288/289): 2302-2306, abr.-maio 2019. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482207

RESUMO

A manteiga é um produto gorduroso obtido pela batenção do creme de leite derivado do leite da vaca, formando uma emulsão do tipo água/óleo. Durante o processo de fabricação, se não houver aplicação de boas práticas, os microrganismos têm grande oportunidade de contaminar a manteiga. Por isso, as práticas higiênico-sanitárias devem ser adotadas com intuito de prevenir eventuais contaminações ou recontaminações do creme. Em Alagoas é comum a comercialização e o consumo de manteiga artesanal, ou seja, manteigas produzidas manualmente, por pequenos produtores/ou pequenos laticínios, bem como manteigas de garrafas ou manteiga da terra que são frequentemente comercializadas diretamente por eles em feiras livres e/ou em pequenos estabelecimentos comerciais. Esta pesquisa objetivou-se avaliar a qualidade microbiológica das manteigas vendidas a granel e manteigas de garrafa vendidas no município de União dos Palmares/AL. Foram coletadas amostras de cada tipo de manteiga em três coletas diferentes em meses seguidos. As análises microbiológicas foram realizadas no Laboratório de Análises Microbiológicas do Instituto Federal de Alagoas-IFAL campus Murici/AL, usando-se a metodologia APHA e como parâmetro de qualidade usou-se o Regulamento técnico de identidade e qualidade. Observou-se com os resultados das análises, que as manteigas vendidas nas feiras e comércios de União dos Palmares/AL, encontravam-se dentro do estabelecido pela legislação vigente.


Assuntos
Higiene dos Alimentos , Manteiga/análise , Manteiga/microbiologia , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação , Técnicas Bacteriológicas/análise
12.
Anal Bioanal Chem ; 410(19): 4669-4677, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29455287

RESUMO

New generation inert ionic liquid (iIL) GC columns IL60i, IL76i and IL111i, comprising phosphonium or imidazolium cationic species, were investigated for separation of fatty acid methyl esters (FAME). In general, the iIL phases provide comparable retention times to their corresponding conventional columns, with only minor selectivity differences. The average tailing factors and peak widths were noticeably improved (reduced) for IL60i and IL76i, while they were slightly improved for IL111i. Inert IL phase columns were coupled with conventional IL columns in comprehensive two-dimensional GC (GC × GC) with a solid-state modulator which offers variable modulation temperature (TM), programmable TM during analysis and trapping stationary phase material during the trap/release (modulation) process, independent of oven T and column sets. Although IL phases are classified as polar, relative polarity of the two phases comprising individual GC × GC column sets permits combination of less-polar IL/polar IL and polar IL/less-polar IL column sets; it was observed that a polar/less-polar column set provided better separation of FAME. A higher first dimension (1D) phase polarity combined with a lower 2D phase polarity, for instance 1D IL111i with 2D IL59 gave the best result; the greater difference in 1D/2D phase polarity results in increasing occupancy of peak area in the 2D space. The IL111i/IL59 column set was selected for analysis of fatty acids in fat and oil products (butter, margarine, fish oil and canola oil). Compared with the conventional IL111, IL111i showed reduced column bleed which makes this more suited to GC × GC analysis of FAME. The proposed method offers a fast profiling approach with good repeatability of analysis of FAME.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Líquidos Iônicos/química , Algoritmos , Manteiga/análise , Cromatografia Gasosa/instrumentação , Esterificação , Ésteres/análise , Óleos de Peixe/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Margarina/análise , Metilação , Óleo de Brassica napus/química
13.
J Texture Stud ; 49(3): 286-292, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29052847

RESUMO

It has been difficult to produce acceptable pecan butters as the high oil content results in a product that flows and separates too easily. The objective of this work was to create pecan butters with varying oil levels (50-70%) and determine which would give the most acceptable product. Consumers rated pecan butters with 55-60% oil the most acceptable, whether roasted or not. Acceptability varied most in terms of texture and spreadability, but not flavor. Under large deformation firmness varied from 51.8 g (70% oil) to 4,880 g (50%) oil, while "spreadability" ranged from 19.2 to 7748 (g/s). Samples with 70% oil had the lowest viscosity and were Newtonian. Pecan butters with 50-55% oil had high viscosity and were shear thinning. Yield stress decreased with oil content, ranging from 0.014 to 500 Pa. The storage modulus (G') increased from ∼7 Pa for samples with 70% oil up to 260,000 Pa for those with 50% oil. In conjunction, tan δ decreased from 1 to 0.07, showing the products take on much more solid-like behavior as oil is removed. In conclusion, the rheological properties of pecan butter were quite sensitive to the amount of oil in the product. Differences in acceptability were primarily due to "texture" and "spreadability," suggesting there is a limited range of firmness and spreadability that consumers will deem acceptable. PRACTICAL APPLICATIONS: There has been considerable demand for butters and spreads made from a variety of culinary nuts. Pecans generally have too much oil (∼70%) to make a product with proper consistency and stability. In this study, some of the oil was removed to overcome this problem. It was found that pecan butter with 55-60% oil was most acceptable to consumers and with the level of firmness, yield stress, and spreadability most similar to commercial nut butters. The oil was relatively simple to remove from unroasted nuts, thus manufacturers could easily produce more acceptable pecan butter for the market.


Assuntos
Manteiga/análise , Carya , Tecnologia de Alimentos , Óleos de Plantas/análise , Humanos , Paladar
14.
Klin Lab Diagn ; 63(5): 260-267, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30689317

RESUMO

In organism, differences in physical chemical properties and physiological role of positional isomeric forms of triglycerides of fatty acids consumed with food are well known. The Raman spectroscopy to analyze there is possible to be applied. Both of these circumstances are to be considered and applied in resolving practical issues of dietetics, i.g., in detection of falsification and replacement of butter and spreads with palm oil, as well as in monitoring ratio of fatty consumed by patients with cardiologic and oncologic pathology. The purpose of study is to determine possibilities of analyzing positional fatty acids isomers specific for butter and palm oil using portable and operational spectrometers of absorption in near infrared range. The technique of projections on latent structures was applied to obtain calibrations of spectrometers to detect content of 7 regulated fatty acids and percentage of milk fat and palm oil in fat-oil mixtures according specters of Raman and near infrared range spectrometers. The possibility of identifying positional isomers of animal and vegetable triglycerides according Raman spectra was confirmed. Besides, it is established that efficiency of determining (reliability, accuracy and selectivity) the proportions of the above oils using both Raman spectra and near-infrared optical density spectra was much higher than when calculating the percentage of the same oils using the content of 7 fatty acids. This fact reflects sensitivity of near infrared range absorption spectra both to length of the carbon chain and degree of unsaturation (number of double bonds C=C) of fatty acids and positional isomeric forms of triglycerides. The obtained data are used in formulating technical requirements and conditions for application of portable near infrared range spectrometer for mass analysis of fat-oil products.


Assuntos
Manteiga/análise , Ácidos Graxos/análise , Óleo de Palmeira/análise , Análise Espectral , Triglicerídeos/análise , Animais , Reprodutibilidade dos Testes
15.
Acta cir. bras ; 32(12): 1013-1025, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886199

RESUMO

Abstract Purpose: To investigate the fatty acid content of different fat sources and evaluate the effect of them on plasma and hepatic lipids and on the fatty acid profile of the brain tissue of Wistar rats. Methods: Thirty male albino Wistar rats received for 59 days, the following diets: diet added of margarine with low content of polyunsaturated fatty acids (PUFA); diet added of margarine with high content of PUFA; diet added of butter; diet added of hydrogenated vegetable fat; diet added of soybean oil. Fatty acid profile of the lipid sources, blood and hepatic lipids fractions and fatty acid profile of the brain tissue were determined. Results: Margarine consumption of provided different responses as to concentrations of blood and hepatic lipid fractions. Intake of butter and hydrogenated increased LDL-c/HDL-c ratio, being the steepest increase promoted by hydrogenated vegetable fat, which also raised LDL-c levels expressively. All fats used in the treatments reduced the cerebral concentration of docosahexaenoic acid when compared to soybean oil (control). Conclusion: The different fat sources commonly consumed by population provided different responses in vivo. This is particularly relevant considering the role of these lipids in the incidence and prevention of cardiovascular diseases.


Assuntos
Animais , Masculino , Ratos , Encéfalo/metabolismo , Manteiga/análise , Ácidos Graxos Insaturados/metabolismo , Lipídeos/sangue , Fígado/metabolismo , Margarina/análise , Triglicerídeos/sangue , Colesterol/sangue , Ratos Wistar , Dieta , Metabolismo dos Lipídeos , Ácidos Graxos Insaturados/química , Crescimento , Hidrogenação , Fígado/química
16.
Food Chem ; 233: 476-482, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28530601

RESUMO

Traditional Tunisian butter (TTB) is one of the most appreciated dairy products in Tunisia. Herein, the storage stability of TTB enriched with antioxidants from tomato processing by-products (TPB) was evaluated during 60days of storage at 4°C. TPB extract contains significant amounts of lycopene and phenolics. TTB enriched with 400mg of TPB extract/kg of TTB revealed the lowest peroxide values at all the determination intervals. Adding 400mg of TPB extract/kg of TTB did not exhibit any undesired effect on lactic bacteria which are necessary for development of aroma and chemical properties of TTB. However, raw TTB and highly enriched TTB (800mg of TPB extract/kg of TTB) displayed higher lipid peroxidation. The detrimental effect of high antioxidant amounts on TTB stability could be due to a possible pro-oxidant character. Thus, appropriate supplementation of TPB extract could be used in TTB as a protective agent against lipid peroxidation to extend its shelf-life up to two months.


Assuntos
Antioxidantes/química , Manteiga/análise , Armazenamento de Alimentos , Extratos Vegetais/química , Solanum lycopersicum/química , Peroxidação de Lipídeos , Tunísia
17.
Sci Total Environ ; 568: 1185-1191, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27173454

RESUMO

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are commonly known as dioxins and are the most toxic members of persistent organic pollutants (POPs) because present a variety of health effects especially as promoting agent of growing and transformation of cancer cells. They are bio-accumulate in humans primarily via the diet, specifically by ingestion of foods that have high lipid content which are generally associated with foods of animal origin such as oils and fats and with fishery and dairy products. In Colombia the Ministry of Health and Social Protection which is the entity responsible for surveillance food conditions, has established maximum levels for dioxins and dl-PCBs in oils from animal and vegetable origins. Oils of vegetable and animal origin represent an appreciable intake in the country thus the presence of dioxins and dl-PCBs in these materials is a matter of concern because they can bioaccumulate in fat. In this contribution the levels of PCDD/Fs and dl-PCBs in olive, soybean, fish oil, butter and shrimp consumed in Colombia were determined using HRGC-HRMS and were compared with the maximum levels permitted in oil samples according to both the Colombian and European regulations. WHO-TEQ concentrations for PCDD/Fs and dioxin like PCBs ranged from 0.24 to 1.710pgWHO-TEQ PCDD/Fg(-1) of fat and from 0.050 to 3.000pgWHO-TEQ PCBg(-1) of fat, respectively. As expected, fish oils and shrimp present the highest WHO-TEQ PCDD/Fs and dl-PCBs values followed by butter and soybean oil sample, while the olive oil shows the lowest levels. In general, the vegetable oils show levels below the limits established by both the Colombian and European regulations. The levels from soybean oil found in this study were slightly higher than the threshold established both by the Commission Regulation European Union (EU) and the Colombian legislation, while fish oils showed concentrations above the European regulations. Furthermore, shrimp exhibited values below the maximum concentration levels established by the EU and Colombian regulation.


Assuntos
Benzofuranos/análise , Dioxinas/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Dibenzodioxinas Policloradas/análise , Animais , Manteiga/análise , Colômbia , Crustáceos/química , Óleos de Peixe/análise , Óleos de Plantas/análise
18.
J Food Sci ; 80(9): C1945-51, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26265530

RESUMO

This study assessed the potential application of gas chromatography (GC) in detecting milk fat (MF) adulteration with vegetable oils and animal fats and of characterizing samples by fat source. One hundred percent pure MF was adulterated with different vegetable oils and animal fats at various concentrations (0%, 10%, 30%, 50%, 70%, and 90%). GC was used to obtain the fatty acid (FA) profiles, triacylglycerol (TG) contents, and cholesterol contents. The pure MF and the adulterated MF samples were discriminated based on the total concentrations of saturated FAs and on the 2 major FAs (oleic acid [C18:1n9c] and linoleic acid [C18:2n6c], TGs [C52 and C54], and cholesterol contents using statistical analysis to compared difference. These bio-markers enabled the detection of as low as 10% adulteration of non-MF into 100% pure MF. The study demonstrated the high potential of GC to rapidly detect MF adulteration with vegetable and animal fats, and discriminate among commercial butter and milk products according to the fat source. These data can be potentially useful in detecting foreign fats in these butter products. Furthermore, it is important to consider that several individual samples should be analyzed before coming to a conclusion about MF authenticity.


Assuntos
Cromatografia Gasosa/métodos , Gorduras na Dieta/análise , Ácidos Graxos/análise , Contaminação de Alimentos/análise , Leite/química , Óleos de Plantas/análise , Animais , Manteiga/análise , Colesterol na Dieta/análise , Comércio , Dieta , Gorduras/análise , Humanos , Ácido Linoleico/análise , Ácido Oleico/análise , Triglicerídeos/análise
19.
Food Funct ; 6(7): 2249-56, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26068124

RESUMO

In Southwest China, tea polyphenols are usually utilized by way of butter tea. Tea polyphenols inhibit the absorption and biosynthesis of fatty acids in vivo, but the effects of butter on the pharmacokinetics of tea polyphenols have drawn less concern. A rapid UHPLC-MS/MS method was used to quantitatively determine the catechins in the plasma, feces and bile of rats after the oral administration of tea polyphenol or its combination with butter. In comparison with the single tea polyphenol treatment, the maximum plasma concentrations (Cmax) of the free EGCG, EGC, EC, GCG, GC and ECG significantly decreased after the co-administration of butter. The mean residence times (MRT) of the free EGCG, EGC, EC, GC and ECG were also significantly prolonged. When the plasma samples were treated with ß-glucuronidase and arylsulfatase, the pharmacokinetic parameters of the total catechins (free and conjugated forms) were not affected by the co-administration of butter. These results indicated that the total absorption of catechins was not affected by butter, but the metabolism of catechins had been changed. Furthermore, the fecal catechins were significantly increased by butter. The total fecal amount and excretion ratio of all catechins were increased highly. The biliary excretion of EGCG, EGC, EC, GCG and GC was significantly increased by the co-administration of butter. To sum up, the butter changed the metabolism of catechins in vivo by decreasing the plasma concentration of the free catechins but increasing the conjugated catechins.


Assuntos
Manteiga/análise , Catequina/metabolismo , Gorduras na Dieta/metabolismo , Fezes/química , Polifenóis/metabolismo , Chá/metabolismo , Animais , Disponibilidade Biológica , Glucuronidase/sangue , Masculino , Ratos , Ratos Sprague-Dawley
20.
Environ Pollut ; 201: 50-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25768883

RESUMO

Limited studies on bioaccumulation of persistent organic pollutants (POPs) along terrestrial food chains were conducted. The food chain air-grass-yak (butter) in the pasture region of Namco in the central Tibetan Plateau (TP) was chosen for study. The air, grass and butter POPs in the TP were at the lower end of the concentrations generally found around the globe. HCB was the main pollutant in air and butter. Besides HCB, ß-HCH and p,p'-DDE were the other major compounds in butter. Along the food chain, DDTs and high molecular weight PCB-138, 153 and 180 had higher Biological Concentration Factor values. The air-butter transfer factors of POPs were derived and demonstrated the practical advantage in predicting the atmospheric OCPs and PCBs to the TP. This study sheds light on the transfer and accumulation of POPs along the terrestrial food chain of the TP.


Assuntos
Poluentes Atmosféricos/análise , Manteiga/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poaceae/química , Animais , Bovinos , Diclorodifenil Dicloroetileno , Monitoramento Ambiental , Hexaclorocicloexano , Bifenilos Policlorados , Tibet
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