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1.
J Oleo Sci ; 67(6): 737-744, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29760328

RESUMO

The in situ polymorphic forms and thermal transitions of refined, bleached and deodorized palm oil (RBDPO), palm stearin (RBDPS) and palm kernel oil (RBDPKO) were investigated using coupled X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results indicated that the DSC onset crystallisation temperature of RBDPO was at 22.6°C, with a single reflection at 4.2Å started to appear from 23.4 to 17.1°C, and were followed by two prominent exothermic peaks at 20.1°C and 8.5°C respectively. Further cooling to -40°C leads to the further formation of a ß'polymorph. Upon heating, a of ß'→ßtransformation was observed between 32.1 to 40.8°C, before the sample was completely melted at 43.0°C. The crystallization onset temperature of RBDPS was 44.1°C, with the appearance of the α polymorph at the same temperature as the appearance of the first sharp DSC exothermic peak. This quickly changed from α→ߴ in the range 25 to 21.7°C, along with the formation of a small ß peak at -40°C. Upon heating, a small XRD peak for the ß polymorph was observed between 32.2 to 36.0°C, becoming a mixture of (ß´+ ß) between 44.0 to 52.5°C. Only the ß polymorph survived further heating to 59.8°C. For RBDPKO, the crystallization onset temperature was 11.6°C, with the formation of a single sharp exothermic peak at 6.5°C corresponding to the ß' polymorphic form until the temperature reached -40°C. No transformation of the polymorphic form was observed during the melting process of RBDPKO, before being completely melted at 33.2°C. This work has demonstrated the detailed dynamics of polymorphic transformations of PKO and PS, two commercially important hardstocks used widely by industry and will contribute to a greater understanding of their crystallization and melting dynamics.


Assuntos
Varredura Diferencial de Calorimetria , Óleo de Palmeira/química , Óleos de Plantas/química , Triglicerídeos/química , Difração de Raios X , Cristalização , Congelamento , Transição de Fase , Pós , Termodinâmica , Temperatura de Transição
2.
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
3.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-237317

RESUMO

<p><b>INTRODUCTION</b>Diabetes mellitus (DM) is a chronic disease that is prevalent in many countries. The prevalence of DM is on the rise, and its complications pose a heavy burden on the healthcare systems and on the patients' quality of life worldwide.</p><p><b>MATERIALS AND METHODS</b>This is a multicentre, cross-sectional study involving 5 Health Clinics conducted by Family Medicine Specialists in Malaysia. Convenience sampling of 100 respondents with DM were selected. The International Classifi cation of Functioning, Disability and Health (ICF) based measures were collected using the Comprehensive Core Set for DM. SF-36 and self-administered forms and comorbidity questionnaire (SCQ) were also used.</p><p><b>RESULTS</b>Ninety-seven percent had Type 2 DM and 3% had Type 1 DM. The mean period of having DM was 6 years. Body functions related to physical health including exercise tolerance (b455), general physical endurance (b4550), aerobic capacity (b4551) and fatiguability (b4552) were the most affected. For body structures, the structure of pancreas (s550) was the most affected. In the ICF component of activities and participation, limitation in sports (d9201) was the highest most affected followed by driving (d475), intimate relationships (d770), handling stress and other psychological demands (d240) and moving around (d455). Only 7% (e355 and e450) in the environmental category were documented as being a relevant factor by more than 90% of the patients.</p><p><b>CONCLUSION</b>The content validity of the comprehensive ICF Core set DM for Malaysian population were identified and the results show that physical and mental functioning were impaired in contrast to what the respondents perceived as leading healthy lifestyles.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Estudos Transversais , Diabetes Mellitus , Classificação , Epidemiologia , Avaliação da Deficiência , Nível de Saúde , Classificação Internacional de Doenças , Malásia , Epidemiologia , Resistência Física , Qualidade de Vida , Inquéritos e Questionários
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-972918

RESUMO

@#目的通过循证和专家讨论研究法建立第一版针对脑卒中的一套综合ICF核心分类模板和与之相应的简明ICF核心分类模板。方法来自于不同国家和地区的国际专家从初步研究中搜集证据,结合这些证据进行正式的决策并最终达成共识。初步研究包括Delphi研究方法、对ICF分类的系统评价以及实证数据的收集。结果来自12个不同国家的39位专家出席会议并达成共识。专家初步研究决定在ICF分类的第二、第三和第四级水平上针对脑卒中确定一套448个类目的ICF核心分类摸板,其中193项类目属于身体功能,26项属于身体结构,165项属于活动和参与,64项属于环境因素。综合性ICF核心分类模板包括在ICF分类第二级水平上的130个类目,其中41项属于"身体功能",5项属于"身体结构",51项属于"活动和参与",33项属于"环境因素"。简明型ICF核心分类模板包括在ICF分类第二级水平上的18个类目,其中6项属于身体功能,2项属于身体结构,7项属于活动参与,以及3项属于环境因素。结论专家组通过整合研究过程中的证据,以及专家们基于ICF框架和分类的观点达成正式的共识,并确定针对"脑卒中"的ICF核心分类模板,同时界定综合型ICF核心分类模板和简要型ICF核心分类模板。

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