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1.
J Sci Food Agric ; 102(4): 1619-1627, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34405412

RESUMO

BACKGROUND: Chemical interesterification (CIE) is one of the important technological processes for the production of zero-trans fats. The aim of this study was to produce trans-free cocoa butter alternatives (CBAs) from palm kernel stearin (PKS), coconut oil (CNO) and fully-hydrogenated palm stearin (FHPS) blends via CIE using sodium methoxide as a catalyst. The physicochemical properties, crystallization and melting behavior, solid fat content (SFC), crystal morphology and polymorphism of the structured lipids (SLs) obtained and the corresponding physical blends (PBs) were characterized and compared with commercial CBAs. RESULTS: After CIE, randomization of fatty acid distribution within and among triacylglycerol (TAG) molecules of PKS, CNO and FHPS resulted in a modification in TAG compositions of the PKS/CNO/FHPS blends and improved the properties and crystallization behavior of the blends. SFC and slip melting points of all SLs decreased from those of their respective PBs. In particular, SLs obtained from CIE of blends with 60-70% wt. PKS (blend ratios 60:10:30 and 70:10:20) exhibited the melting characteristic, SFC curves, crystal morphology and polymorphic form most similar to the commercial CBAs. In addition, these blends melted almost completely at body temperature, an improvement from that of the commercial CBAs. CONCLUSION: SLs obtained from CIE of blends with 60-70% wt. PKS has high potential to be used commercially as trans-free CBAs for the confectionery industry. © 2021 Society of Chemical Industry.


Assuntos
Óleos de Plantas , Óleo de Coco , Gorduras na Dieta , Esterificação , Óleo de Palmeira , Triglicerídeos
2.
Crit Rev Food Sci Nutr ; 57(1): 48-58, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-26048727

RESUMO

Lipid is the general name given to fats and oils, which are the basic components of cooking oils, shortening, ghee, margarine, and other edible fats. The chosen term depends on the physical state at ambient temperature; fats are solids and oils are liquids. The chemical properties of the lipids, including degree of saturation, fatty acid chain length, and acylglycerol molecule composition are the basic determinants of physical characteristics such as melting point, cloud point, solid fat content, and thermal behavior. This review will discuss the major lipid modification strategies, hydrogenation, and chemical and enzymatic interesterification, describing the catalysts used mechanisms, kinetics, and impacts on the health-related properties of the final products. Enzymatic interesterification will be emphasized as method that produces a final product with good taste, zero trans fatty acids, and a low number of calories, requires less contact with chemicals, and is cost efficient.


Assuntos
Gorduras na Dieta/análise , Gorduras/química , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Tecnologia de Alimentos , Saúde Global , Ácidos Graxos trans/efeitos adversos , Animais , Fenômenos Químicos , Comportamento do Consumidor , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Esterificação , Qualidade dos Alimentos , Tecnologia de Alimentos/tendências , Humanos , Hidrogenação , Lipase/química , Lipase/metabolismo , Estrutura Molecular , Estereoisomerismo , Ácidos Graxos trans/análise , Ácidos Graxos trans/química , Ácidos Graxos trans/metabolismo
3.
Food Technol Biotechnol ; 53(3): 361-366, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27904370

RESUMO

The optimal physical, chemical and nutritional properties of natural lipids depend on the structure and composition of triacylglycerols. However, they are not always mutually compatible. Lipid modification is a good way to give them specific functionalities, increase their oxidative stability, or improve their nutritional value. As such, chemical and enzymatic interesterification may be used to modify them and produce structured lipids. In accordance, the aim of this study is to compare chemical and enzymatic interesterification of binary blends of fully hydrogenated soybean oil and walnut oil, using sodium methoxide or Lipozyme TL IM, respectively, to produce a fat base with adequate nutritional and physical characteristics. Three different mass ratios of fully hydrogenated soybean oil and walnut oil blends (20:80, 40:60 and 60:40) were interesterified and evaluated. Total interesterification was determined by the stabilization of the solid fat content. Chemical reaction of the 20:80 blend was completed in 10 min and of the 40:60 and 60:40 blends in 15 min. Enzymatically interesterified blends were stabilized in 120 min at all of the mass ratios. Complete interesterification significantly reduced the solid fat content of the blends at any composition. Chemical and enzymatically interesterified fully hydrogenated blend of soybean and walnut oil at mass ratio of 40:60 showed the plastic curve of an all-purpose- -type shortening rich in polyunsaturated fatty acids, with a high linolenic acid (C18:3n3) content and with zero trans-fatty acids.

4.
J Food Sci Technol ; 52(2): 876-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25694696

RESUMO

The effects of 400 ppm ascorbyl palmitate (AP) on fatty acids composition, tocopherol, peroxide value (PV) and malonaldehyde (MAD) contents of refined cottonseed oil (CO) and virgin olive oil (OO) during chemical interesterification (CI), and storage at 60 °C for 28 days were investigated. CI significantly decreased (p < 0.05) the tocopherol contents of CO and OO. PVs and MAD contents of oil samples considerably increased up to 20 min of CI, followed by a reduction at 30 min. The unsaturated fatty acids/saturated fatty acids (UFA/SFA) ratios of the samples showed slight but significant (p < 0.05) reduction during accelerated oxidation process. Oils with added 400 ppm AP had higher tocopherol, and lower PVs and MAD contents than their counterparts without AP during CI, and storage at 60 °C. AP increased the oxidative stability of interesterified and non-interesterified CO and OO.

5.
Foods ; 10(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670550

RESUMO

Unlike other fields, the methods routinely applied for fats and oils are still tied to traditional, time- and solvent-consuming procedures, such as saponification, column chromatography and thin-layer chromatography. In this paper, microwave-assisted saponification followed by a lab-made solid-phase extraction was optimized for the characterization of either dialkyl ketones (DAK) or sterols or both simultaneously. The instrumental determination was performed by gas chromatography- flame ionization detector (GC-FID) for quantification and gas chromatography-mass spectrometry (GC-MS) for confirmation purposes. The proposed method showed good recoveries (>80%) and limit of quantification (0.04-0.07 µg/g for the 4 DAK and of 0.07 µg/g for α-cholestanol). Repeatabilities (n = 3) were below 15% for DAKs and generally lower than 6% for sterols. Accuracy on the entire sterol profile was confirmed in comparison to the International Olive Council reference method. The method was finally applied to real-world samples before and after chemical interesterification.

6.
Food Sci Nutr ; 7(11): 3722-3730, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31763021

RESUMO

In this study, production of trans-free fats through chemical interesterification of binary blends of palm stearin (PS) and sunflower oil (SFO) and their physicochemical changes after the process was investigated. Analyzed responses included fatty acid and triacylglycerol composition, iodine value, free fatty acid (FFA), soap content, peroxide value (PV), plastic range, slip melting point (SMP), solid fat content (SFC), and oxidative stability along with potential applications of the interesterified fats. Transfatty acid content of PS/SFO blends was lower than 0.36%. Chemical interesterification increased the FFA and soap content and also decreased PV and oxidative stability index (at 110°C). After the process, SMP and SFC were reduced, also the plastic range transferred to the lower temperatures. All the interesterified blends melted completely at the body temperature, and their SFC was <32%. The melting characteristics of the PS/SFO-interesterified blends were suitable for many fat-based products.

7.
Food Res Int ; 106: 982-991, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29580013

RESUMO

Interesterification reaction involves rearrangement of the fatty acid radicals on the glycerol backbone, either randomly (chemical interesterification) or regioselectivity (enzymatic interesterification). Refined, bleached and deodourised palm oil (RBDPO) and palm kernel oil (RBDPKO) were blended in ratios from 25:75 to 75:25 (wt/wt). All blends were subjected to enzymatic (EI) and chemical interesterification (CI) using Lipozyme TL IM (4% w/w) and sodium methoxide (0.2% m/m) as the catalysts, respectively. The effect of EI and CI on the triacylglycerol (TAG) composition, thermal behaviour, polymorphism, crystal morphology and crystallisation kinetics were studied. The aim of this research is to characterise the nature of crystals in food product for certain desired structure. The crystallisation behaviour discussed in this study involves microstructure (PLM), polymorphism (XRD), thermal properties and crystallisation kinetics by DSC. The alteration in TAG composition was greater after CI as compared to EI with the reduction of LaLaLa (from 11.00% to 5.15%) and POO (from 14.28% to 4.87%). The DSC complete melting and crystallisation temperature of blend with 75% PO increased after CI, from 39.58 °C to 41.67 °C and from -30.84 °C to -28.33 °C, respectively. EI contributed to finer crystals than CI. However, the ß' and ß polymorph mixture and crystallisation kinetics (n = 2) of PO-PKO blends did not change after CI and EI. The knowledge on controlling crystallisation of RBDPO and RBDPKO blends is vital for proper processing condition like margarine production.


Assuntos
Manipulação de Alimentos/métodos , Óleo de Palmeira , Óleos de Plantas , Cristalização , Esterificação , Temperatura Alta , Óleo de Palmeira/análise , Óleo de Palmeira/química , Óleos de Plantas/análise , Óleos de Plantas/química , Triglicerídeos/análise , Triglicerídeos/química
8.
Food Chem ; 215: 369-76, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27542488

RESUMO

The present study sought to develop lipid bases from blends between patawa oil and palm stearin. These blends were analyzed before and after the chemical interesterification process for their fatty acid and triacylglycerol composition, free fatty acid (FFA) content, peroxide index, thermal properties, melting point, consistency, and solid fat content (SFC). Blends with unsaturated fatty acid contents between 60 and 70% were obtained, with a good ratio between saturated and unsaturated fatty acids, which indicates a healthy content of fatty acids. Variations in the triacylglycerol contents and melting and crystallization thermograms evidenced the reaction. The blend with 50% stearin and 50% patawa oil showed the best results after the chemical interesterification reaction regarding the possible application in fatty products for its appropriate melting point, SFC similar to that of soft table margarines, plastic and spreadable consistency at refrigeration temperature, thus combining physical and nutritional properties desirable for the food industry.


Assuntos
Esterificação , Óleos de Plantas/química , Fenômenos Químicos , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos não Esterificados , Lipídeos/química , Margarina , Óleo de Palmeira , Triglicerídeos/análise , Triglicerídeos/química
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