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1.
Food Res Int ; 186: 114381, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729735

RESUMO

Lipid has crucial applications in improving the quality of starchy products during heat processing. Herein, the influence of lipid modification and thermal treatment on the physicochemical properties and starch digestibility of cooked rice prepared with varied addition manipulations was investigated. Rice bran oil (RO) and medium chain triglyceride oil (MO) manipulations were performed either before (BC) or after cooking (AC). GC-MS was applied to determine the fatty acid profiles. Nutritional quality was analyzed by quantifying total phenolics, atherogenic, and thrombogenic indices. All complexes exhibited higher surface firmness, a soft core, and less adhesive. FTIR spectrum demonstrated that the guest component affected some of the dense structural attributes of V-amylose. The kinetic constant was in the range between 0.47 and 0.86 min-1 wherein before mode presented a higher value. The lowest glucose release was observed in the RO_BC sample, whereas the highest complexing index was observed in the RO_AC sample, indicating that the dense molecular configuration of complexes that could resist enzymatic digestion was more critical than the quantity of complex formation. Despite the damage caused by mass and heat transfer, physical barrier, intact granule forms, and strengthened dense structure were the central contributors affecting the digestion characteristics of lipid-starch complexes.


Assuntos
Culinária , Digestão , Oryza , Óleo de Farelo de Arroz , Amido , Triglicerídeos , Oryza/química , Amido/química , Óleo de Farelo de Arroz/química , Triglicerídeos/química , Temperatura Alta , Ácidos Graxos/análise , Ácidos Graxos/química , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Valor Nutritivo , Amilose/química , Cromatografia Gasosa-Espectrometria de Massas
2.
J Oleo Sci ; 73(5): 637-644, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38692888

RESUMO

Epoxy fatty acid formation during heating was estimated using triolein (OOO) and trilinolein (LLL). Epoxy octadecanoic acids were found in heated OOO, while epoxy octadecenoic acids were found in heated LLL. The content of epoxy fatty acids increased with heating time, and trans-epoxy fatty acids were formed significantly more than cis-epoxy fatty acids. A comparison between OOO and LLL indicated that epoxy fatty acid formation was higher in the OOO than that in the LLL. Heating tests in the presence of α- tocopherol suggested that the formation of epoxy fatty acids could be suppressed by antioxidants.


Assuntos
Antioxidantes , Compostos de Epóxi , Ácidos Graxos , Temperatura Alta , Triglicerídeos , Ácidos Graxos/análise , Antioxidantes/análise , Triglicerídeos/análise , Triglicerídeos/química , alfa-Tocoferol/análise , Trioleína/química , Fatores de Tempo
3.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731587

RESUMO

We aimed to obtain the optimal formula for human milk fat substitute (HMFS) through a combination of software and an evaluation model and further verify its practicability through an animal experiment. The results showed that a total of 33 fatty acid (FA) and 63 triglyceride (TAG) molecular species were detected in vegetable oils. Palmitic acid, oleic acid, linoleic acid, 18:1/16:0/18:1, 18:2/16:0/18:2, 18:1/18:1/18:1 and 18:1/18:2/18:1, were the main molecular species among the FAs and TAGs in the vegetable oils. Based on the HMFS evaluation model, the optimal mixed vegetable oil formula was blended with 21.3% palm oil, 2.8% linseed oil, 2.6% soybean oil, 29.9% rapeseed oil and 43.4% maize oil, with the highest score of 83.146. Moreover, there was no difference in the weight, blood routine indices or calcium and magnesium concentrations in the feces of the mice between the homemade mixed vegetable oil (HMVO) group and the commercial mixed vegetable oil (CMVO) group, while nervonic acid (C24:1) and octanoic acid (C8:0) were absorbed easily in the HMVO group. Therefore, these results demonstrate that the mixing of the different vegetable oils was feasible via a combination of computer software and an evaluation model and provided a new way to produce HMFS.


Assuntos
Substitutos da Gordura , Ácidos Graxos , Leite Humano , Óleos de Plantas , Software , Triglicerídeos , Humanos , Animais , Óleos de Plantas/química , Ácidos Graxos/química , Leite Humano/química , Camundongos , Triglicerídeos/química , Substitutos da Gordura/química , Óleo de Palmeira/química , Óleo de Soja/química , Óleo de Semente do Linho/química , Óleo de Brassica napus/química , Óleo de Milho/química , Caprilatos/química , Ácido Palmítico/química , Ácido Oleico/química
4.
J Agric Food Chem ; 72(15): 8849-8858, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38580310

RESUMO

Comprehensive analysis of triacylglycerol (TAG) regioisomers is extremely challenging, with many variables that can influence the results. Previously, we reported a novel algorithmic method for resolving regioisomers of complex mixtures of TAGs. In the current study, the TAG Analyzer software and its mass spectrometric fragmentation model were further developed and validated for a much wider range of TAGs. To demonstrate the method, we performed for the first time a comprehensive analysis of TAG regioisomers of bovine milk fat, a very important and one of the most complex TAG mixtures in nature containing FAs ranging from short to long carbon chains. This analysis method forms a solid basis for further investigation of TAG regioisomer profiles in various natural fats and oils, potentially aiding in the development of new and healthier foods and nutraceuticals with targeted lipid structures.


Assuntos
Leite , Espectrometria de Massas em Tandem , Animais , Triglicerídeos/química , Leite/química , Gorduras/análise , Software
5.
Int J Pharm ; 656: 124108, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604540

RESUMO

Lipid-based formulations (LbFs) are an extensively used approach for oral delivery of poorly soluble drug compounds in the form of lipid suspension and lipid solution. However, the high target dose and inadequate lipid solubility limit the potential of brick dust molecules to be formulated as LbFs. Thus, the complexation of such molecules with a lipophilic counterion can be a plausible approach to improve the solubility in lipid-based solutions via reducing drug crystallinity and polar surface area. The study aimed to enhance drug loading in lipid solution for Nilotinib (Nil) through complexation or salt formation with different lipophilic counterions. We synthesized different lipophilic salts/ complexes via metathesis reactions and confirmed their formation by 1H NMR and FTIR. Docusate-based lipophilic salt showed improved solubility in medium-chain triglycerides (∼7 to 7.5-fold) and long-chain triglycerides (∼30 to 35-fold) based lipids compared to unformulated crystalline Nil. The increased lipid solubility could be attributed to the reduction in drug crystallinity which was further confirmed by the PXRD and DSC. Prototype LbFs were prepared to evaluate drug loading and their physicochemical characteristics. The findings suggested that structural features of counterion including chain length and lipophilicity affect the drug loading in LbF. In addition, physical stability testing of formulations was performed, inferring that aliphatic sulfate-based LbFs were stable with no sign of drug precipitation or salt disproportionation. An in vitro lipolysis-permeation study revealed that the primary driver of absorptive flux is the solubilization of the drug and reduced amount of lipid. Further, the in vivo characterization was conducted to measure the influence of increased drug load on oral bioavailability. Overall, the results revealed enhanced absorption of lipophilic salt-based LbF over unformulated crystalline Nil and conventional LbF (drug load equivalent to equilibrium solubility) which supports the idea that lipophilic salt-based LbF enhances drug loading, and supersaturation-mediated drug solubilization, unlocking the full potential of LbF.


Assuntos
Lipídeos , Sais , Solubilidade , Sais/química , Animais , Lipídeos/química , Masculino , Administração Oral , Composição de Medicamentos/métodos , Pirimidinas/química , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Poeira , Liberação Controlada de Fármacos , Ratos , Química Farmacêutica/métodos , Interações Hidrofóbicas e Hidrofílicas , Triglicerídeos/química , Estabilidade de Medicamentos , Portadores de Fármacos/química , Cristalização
6.
Food Funct ; 15(8): 4399-4408, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38563197

RESUMO

A Pickering emulsion is an emulsion system stabilized by solid particles and represents a promising candidate for emulsifying lipids. Cellulose nanofibers (CNFs) have excellent ability to control the lipid release rate. This study aims to find the optimal formulation for a nanocellulose-stabilized Pickering emulsion that is the most effective in reducing the lipid release rate. The Pickering emulsion was prepared by homogenizing pretreated nanocellulose with medium-chain triglycerides using high-speed and ultrasonic homogenizers. The results show that the Pickering emulsion with 0.709% nanocellulose and 30.6% medium-chain fatty acid content yielded an average particle size of approximately 2.5 µm, which is the most stable and effective in reducing the amount of the lipids released. The nanocellulose Pickering emulsion formulation developed in this study forms a significant foundation for future research and applications regarding the use of nanotechnology and Pickering emulsions to maintain the balance between one's health and the desirable flavor of fat.


Assuntos
Celulose , Emulsões , Nanofibras , Tamanho da Partícula , Celulose/química , Emulsões/química , Nanofibras/química , Lipídeos/química , Triglicerídeos/química , Animais , Humanos
7.
J Agric Food Chem ; 72(15): 8859-8870, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564481

RESUMO

In this study, an enzymatic reaction was developed for synthesizing pure triacylglycerols (TAG) with a high content of palmitoleic acid (POA) using fish byproduct oil. The characteristics of synthesized structural TAGs rich in POA (POA-TAG) were analyzed in detail through ultrahigh-performance liquid chromatography Q Exactive orbitrap mass spectrometry. Optimal conditions were thoroughly investigated and determined for reaction systems, including the use of Lipozyme TL IM and Novozym 435, 15 wt % lipase loading, substrate mass ratio of 1:3, and water content of 2.5 and 0.5 wt %, respectively, resulting in yields of 67.50 and 67.45% for POA-TAG, respectively. Multivariate statistical analysis revealed that TAG 16:1/16:1/20:4, TAG 16:1/16:1/16:1, TAG 16:1/16:1/18:1, and TAG 16:0/16:1/18:1 were the main variables in Lipozyme TL IM and Novozym 435 enzyme-catalyzed products under different water content conditions. Finally, the fate of POA-TAG across the gastrointestinal tract was simulated using an in vitro digestion model. The results showed that the maximum release of free fatty acids and apparent rate constants were 71.44% and 0.0347 s-1, respectively, for POA-TAG lipids, and the physical and structural characteristics during digestion depended on their microenvironments. These findings provide a theoretical basis for studying the rational design of POA-structural lipids and exploring the nutritional and functional benefits of POA products.


Assuntos
Ácidos Graxos Monoinsaturados , Óleos de Peixe , Água , Triglicerídeos/química , Óleos de Peixe/química , Digestão
8.
Molecules ; 29(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675667

RESUMO

The process of lipid crystallization influences the characteristics of lipid. By changing the chemical composition of the lipid system, the crystallization behavior could be controlled. This review elucidates the internal factors affecting lipid crystallization, including triacylglycerol (TAG) structure, TAG composition, and minor components. The influence of these factors on the TAG crystal polymorphic form, nanostructure, microstructure, and physical properties is discussed. The interplay of these factors collectively influences crystallization across various scales. Variations in fatty acid chain length, double bonds, and branching, along with their arrangement on the glycerol backbone, dictate molecular interactions within and between TAG molecules. High-melting-point TAG dominates crystallization, while liquid oil hinders the process but facilitates polymorphic transitions. Unique molecular interactions arise from specific TAG combinations, yielding molecular compounds with distinctive properties. Nanoscale crystallization is significantly impacted by liquid oil and minor components. The interaction between the TAG and minor components determines the influence of minor components on the crystallization process. In addition, future perspectives on better design and control of lipid crystallization are also presented.


Assuntos
Cristalização , Triglicerídeos , Triglicerídeos/química , Lipídeos/química , Ácidos Graxos/química
9.
Colloids Surf B Biointerfaces ; 238: 113873, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552410

RESUMO

In this study, the critical importance of designing an appropriate immobilized carrier and method for free lipase to ensure exceptional biological catalytic activity and stability was emphasized. Covalent organic frameworks (COF-1) were synthesized as a novel porous carrier with an azine structure (-CN-NC-) through the condensation of hydrazine hydrate and benzene-1,3,5-tricarbaldehyde at room temperature. Simultaneously, Rhizomucor miehei lipase (RML) was immobilized within the COF-1 carrier using an in-situ aqueous phase method. Characterization of the carrier and RML@COF-1 and evaluation of the lipase properties of RML and RML@COF-1 through p-Nitrophenyl palmitate hydrolysis were conducted. Additionally, application in the synthesis of 1, 3-dioleoyl-2-palmitoylglycerol (OPO) was explored. The results showed that RML@COF-1 exhibited a high enzymatic loading of 285.4 mg/g. Under 60℃ conditions, the activity of RML@COF-1 was 2.31 times higher than that of free RML, and RML@COF-1 retained 77.25% of its original activity after 10 cycles of repeated use, indicating its excellent thermal stability and repeatability. Under the optimal conditions (10%, 1:8 PPP/OA, 45℃, 5 h), the yield of OPO reached 47.35%, showcasing the promising application prospects of the novel immobilized enzyme synthesized via in-situ aqueous phase synthesis for OPO preparation.


Assuntos
Enzimas Imobilizadas , Lipase , Rhizomucor , Lipase/metabolismo , Lipase/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Rhizomucor/enzimologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/síntese química , Hidrólise , Porosidade , Propriedades de Superfície , Triglicerídeos/química , Triglicerídeos/metabolismo
10.
J Oleo Sci ; 73(4): 445-454, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556279

RESUMO

High-performance size exclusion chromatography (HPSEC) equipped with an evaporative light scattering detector (ELSD) was utilized for characterization of palm fatty acid distillate (PFAD) and its esterified products, with a particular focus on lipid profiles and diacylglycerol (DAG) regioisomers. The separation of triacylglycerol (TAG), DAG, monoacylglycerol (MAG), and free fatty acid (FFA) was achieved through a single 100-Å Phenogel column, coupled with a 2-cm C18 guard, utilizing toluene/acetic acid (100:0.25, v/v) as the mobile phase. This separation was based on size sieving principles and the interactions between the hydroxyl group(s) and the Phenogel matrix. The limit of detection (LOD) and limit of quantification (LOQ) for the esterified PFAD products analyzed by this method fell within the range of 4.8-5.5 µg/mL and 14.7-16.7 µg/mL, respectively. Additionally, the same column, paired with a 2-cm silica guard and a mobile phase comprised of toluene/isooctane/acetic acid (35:65:0.15, v/v/v), was used for the characterization of DAG regioisomers within the esterified PFAD. LODs and LOQs for sn-1,3-DAG and sn- 1,2-DAG were determined to be 39.2 and 118.7 µg/mL, and 32.8 and 99.5 µg/mL, respectively. Investigation of esterified PFAD products prepared using 4% H2SO4 at 120°C. After 2 h, the analysis revealed the highest MAG content at 31.85%, accompanied by 51.54% DAG, 2.35% TAG, and a residual 14.27% FFA. Notably, as the reaction time extended, the MAG content decreased, while both DAG and TAG levels exhibited an increasing trend. Further examination of DAG regioisomers during PFAD esterification, under varying catalyst concentrations (2-10%) and reaction temperatures (80-140°C), demonstrated a significant increase in the percentage of sn-1,3-DAG, inversely correlated with the reduction in FFA from 2% H 2 SO 4 and 80°C onwards. Remarkably, the percentage of sn-1,2-DAG remained relatively stable regardless of changes in catalyst concentrations or temperatures, confirming its susceptibility to isomerization into the thermodynamically more stable sn-1,3-DAG form. This study provides valuable insights into the composition and behavior of esterified PFAD products.


Assuntos
Diglicerídeos , Ácidos Graxos não Esterificados , Esterificação , Triglicerídeos/química , Ácidos Graxos não Esterificados/análise , Ácidos Graxos , Monoglicerídeos , Cromatografia em Gel , Acetatos , Tolueno
11.
Food Chem ; 444: 138635, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38325087

RESUMO

The relationship between batch and continuous enzymatic interesterification was studied through enzymatic interesterification of beef tallow. The interesterification degree (ID) during the batch reaction was monitored based on triacylglycerol composition, sn-2 fatty acid composition, solid fat content, and melting profile and was described by an exponential model. A relationship equation featuring reaction parameters of the two reations was established to predict the ID and physicochemical characteristics in continuous interesterification. The prediction of the ID based on triacylglycerol composition was reliable, with an R2 value greater than 0.85. Interesterification produced more high-melting-point components for both reactions, but the acyl migration in the batch-stirring reactor was much greater, resulting in faster crystallization, a more delicate crystal network, and lower hardness. The relationship equation can be employed to predict the ID, but the prediction of physicochemical properties was constrained by the difference in acyl migration degree between the two reactions.


Assuntos
Gorduras , Ácidos Graxos , Animais , Bovinos , Esterificação , Gorduras/química , Triglicerídeos/química , Ácidos Graxos/química , Óleos de Plantas/química
12.
Food Chem ; 443: 138546, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301557

RESUMO

Preterm formulas are usually supplemented with medium-chain triacylglycerols (MCT) whereas breast milk contains more medium and long-chain triacylglycerols (MLCT). Different types of triacylglycerol (TAG) containing medium-chain fatty acids may influence lipid digestion. In this study, the digestive characteristics of breast milk and preterm formulas with different MCT contents were evaluated using a dynamic in vitro system simulating the gastrointestinal tract of preterm infants. The lipolysis products, including diacylglycerols, monoacylglycerols (MAGs), free fatty acids, and undigested TAGs, were analyzed. Formulas with MCT addition has significantly (P < 0.05) lower lipolysis degree (LD, 69.35%-71.28%) than breast milk (76.93%). Higher amounts of C8:0 and C10:0 were released in the formulas with MCT addition. Breast milk released more C18:1n-9, C18:2n-6, and MAG containing C16:0, whereas formulas released more free C16:0. The Pearson correlation heatmap showed that the LD value was significantly and positively (P < 0.05) related to the MLCT and sn-2 C16:0 content.


Assuntos
Ácidos Graxos , Recém-Nascido Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Triglicerídeos/química , Ácidos Graxos/análise , Leite Humano/química , Digestão
13.
Food Res Int ; 180: 114059, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395552

RESUMO

Ketogenic diet, characterized by high fat and low carbohydrate content, is gradually becoming a new perspective in the human diet; however, the mechanism of digestion of ketogenic diet remains unknown. In this study, we explored the oil-water interface to elucidate the digestion of a ketogenic diet based on typical representative medium- and long-chain triglycerides. The free fatty acids (FFAs) release indicated that glycerol trioctanoate with a shorter carbon chain (FFA = 920.55 ± 10.17 µmol) was significantly more digestible than glycerol tripalmitate (851.36 ± 9.48 µmol) and glycerol tristearate (805.81 ± 10.03 µmol). Particle size analysis revealed that the length of the carbon chain increased the size of triglycerides, resulting in a decreased contact area with lipase. The interfacial phenomenon indicated that the longer the carbon chain of triglycerides, the greater the reduction in binding capacity with salt ions in the digestive solution. Fluorescence spectroscopy analysis showed that the length of the carbon chain induced the displacement of the lipase peak, suggesting that the carbon chain length could alter the structure of lipase. Molecular dynamics simulation showed that the longer the carbon chain of triglycerides, the easier it was to loosen the structure of lipase. Bond energy analysis showed that the carbon chain length of triglycerides was positively correlated with the bond energy strength of the ester bonding. In conclusion, this study emphasizes that the ketogenic diet should primarily consist of shorter carbon chain triglycerides because carbon chain length can alter the digestion of triglycerides. This provides a new perspective on the quest for more effective ketogenic diet, in line with the current view of healthy diet.


Assuntos
Dieta Cetogênica , Humanos , Glicerol , Triglicerídeos/química , Lipase/metabolismo , Digestão , Carbono
14.
J Agric Food Chem ; 72(6): 3180-3188, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38308634

RESUMO

Fatty acids (FAs) containing polymethylene-interrupted (PMI) double bonds are a component of human foods; however, they present a significant analytical challenge for de novo identification. Covalent adduct chemical ionization and ozone-induced dissociation mass spectrometry (MS) methods enable unambiguous assignment of PMI-FA double bond positions, however, no method has been reported with electrospray ionization (ESI) platform using off-the-shelf systems. In the current work, we studied the Paternò-Büchi (PB) fragmentation patterns of PMI-FA and triacylglycerol (TG) by analyzing several known food sources. PB-MS/MS and MS3 enabled complete double bond location assignments, including the isolated double bond in PMI-FA and triacylglycerols. Sea urchin ("uni"), oyster, pine nut, and ginkgo nut were characterized for their signature PMI-FA, 20:2(5Z,11Z), 22:2(7Z, 15Z), 18:3(5Z,9Z,12Z), and 20:3(5Z,11Z,14Z), respectively. Quantitative analyses of the relative abundance of these PMI-FA led to results similar to reference methods. 18:3(5Z,9Z,12Z) was enriched at the sn-1/sn-3 position in pine nut major TG.


Assuntos
Ácidos Graxos , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos/química , Triglicerídeos/química , Alimentos , Espectrometria de Massas por Ionização por Electrospray/métodos
15.
Food Res Int ; 178: 113750, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309857

RESUMO

Hydroxy- and peroxy-triacylglycerols are common products of lipid peroxidation formed during oil storage or heating or as enzymatic oxidation product of arachidonic acid as signaling molecules in mammals. In this study, oxygenated triacylglycerides (TAG) were identified in pistachio oil based on reverse phase(RP), high-performance liquid chromatography coupled with electrospray ionization and mass spectrometry (HPLC- ESI -MS). 20 novel lipid plant metabolites, classified based on their fragment spectra into a hydroxy (TAG-OH), an epoxy (TAG-O), and hydroperoxide (TAG-OOH) groups. We believe that this class of compounds has been for the first time observed as genuine secondary plant metabolites in a natural source in this case pistachio lipids of dietary relevance.


Assuntos
Pistacia , Espectrometria de Massas por Ionização por Electrospray , Animais , Espectrometria de Massas por Ionização por Electrospray/métodos , Triglicerídeos/química , Nozes/química , Cromatografia de Fase Reversa , Mamíferos
16.
Food Chem ; 443: 138522, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277931

RESUMO

We performed a nanoscale study based on X-ray scattering to understand the impact of a promotor of crystallization, palmitic acid (PA), at high concentration, on the networks of triacylglycerols (TAGs) in anhydrous milk fat (AMF). Melted blends containing 10 wt% PA were quenched at 25 °C. X-ray scattering data were compared with those obtained for pure AMF, pure PA, and AMF containing 1 wt% PA. While PA at low concentration did not modify the nanostructure of TAG crystals (direct crystallization in the ß'-2L form), a high concentration of this promotor favored the formation of polymorphic forms suggesting that PA first crystallizes and then directs crystallization of AMF TAGs towards α and ß forms.


Assuntos
Leite , Ácido Palmítico , Animais , Ácido Palmítico/análise , Leite/química , Triglicerídeos/química , Cristalização
17.
Food Res Int ; 177: 113864, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225135

RESUMO

Cocoa butter equivalents (CBE) are mixtures of triglycerides from multiple sources (e.g., sunflower oil, mango kernel and sal), which resemble cocoa butter (CB) in both physical and chemical properties. Despite being widely used to replace CB in chocolate products, the crystallization behavior of many CBEs is still poorly understood. The aim of this work was to develop a fundamental understanding, at the molecular level, of the crystallization behavior of selected CBEs, and compare it with that of CB. Chromatography was used to determine the composition of CBEs, in terms of fatty acids and triacylglycerides (TAGs), while their thermodynamic behavior and crystallization kinetics were studied using polarized microscopy, differential calorimetry and three different synchrotron X-ray scattering setups. CBEs of different origin and chemical composition (e.g., different ratios of the main CB TAGs, namely POP, SOS and POS) crystallized in different polymorphs and with different kinetics of nucleation, growth and polymorphic transformation. SOS rich CBEs presented showed more polymorphs than CB and POP rich samples; whereas, CBEs with high concentration of POP showed slow kinetic of polymorphic transformation towards the stable ß(3L) form. Additionally, it was observed that the presence of small amounts (<1% w/w) of specific TAGs, such as OOO, PPP or SSS, could significantly affect the crystallization behavior of CBEs and CBs in terms of kinetics of polymorphic transformation and number of phases detected (multiple high melting ß(2L) polymorphs were identified in all samples studied). Finally, it was found that, regardless of the CBE composition, the presence of shear could promote the formation of stable ß polymorphs over metastable ß' and γ forms, and reduced the size of the crystal agglomerates formed due to increased secondary nucleation.


Assuntos
Ácidos Graxos , Síncrotrons , Cristalização , Raios X , Triglicerídeos/química , Ácidos Graxos/análise
18.
Food Res Int ; 177: 113911, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225148

RESUMO

Thermophysical properties of blends composed of soybean oil and fats obtained from fruits and seeds from Brazilian Amazonian region (Murumuru, Tucuma, and Bacuri) were investigated, looking for more sustainable alternatives to the mostly used industrial fats, for applications in product formulation. Fatty acid (FA) and triacylglycerol composition, nutritional indexes, solid fat content (SFC), compatibility, consistency, melting, and crystallization profiles were determined. Soybean oil increased blends' unsaturated FA profile, leading to lower SFC, but higher nutritional quality. Fats' melting profiles were significantly altered with soybean oil addition: temperatures decreased with the increase in oil content. Iso-solids diagrams showed that lipids were compatible, which is a technological advantage. SFC and consistency profiles suggested that tucuma and murumuru fats could be used as hardstocks for lipid products, and bacuri fat could be applied in products such as margarine and spreads. Blends could improve fats' spreadability and other technological properties, which is promising for applications in products formulation.


Assuntos
Óleos de Plantas , Óleo de Soja , Óleo de Soja/química , Óleos de Plantas/química , Gorduras/química , Triglicerídeos/química , Ácidos Graxos/química
19.
Langmuir ; 40(5): 2500-2509, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38284535

RESUMO

The role of triglycerides (TGs) in both natural and synthetic biological membranes has long been the subject of study, involving metabolism, disease, and colloidal synthesis. TGs have been found to be critical components for successful liposomal encapsulation via a water/oil/water double emulsion, which this work endeavors to explain. TGs can occupy multiple positions in biological membranes. The glycerol backbone can reside at the water/organic interface, adjacent to phospholipid headgroups ("m" conformation), typically with relatively low (<3%) solubility. The glycerol backbone can also occupy hydrophobic regions, where it is isolated from water ("h" or "oil" conformation). This can occur in either midmembrane positions or phospholipid-coated lipid droplets (LDs). These conformations can be distinguished using 13C-nuclear magnetic resonance spectroscopy (NMR), which determines the degree of hydration of the TG backbone. Using this method, it was revealed that TGs transition from "m" to "h" conformation as the organic solvent is removed via evaporation. A new transitional TG backbone position has been identified with a level of hydration between "m" and "h". These results suggest that TGs can temporarily coat and stabilize the large water/organic interfaces present after emulsification. As the organic solvent is removed and interfaces shrink, the TGs recede into midmembrane spaces or bud off into LDs, which are confirmed via transmission electron microscopy (TEM) and can be removed via centrifugation. Encapsulation efficiency is found to be inversely related to both the saturation and length of the TG acyl chains, indicating that membrane fluidization is a key property arising from the presence of TGs. Beyond clarification of a mechanism for high-efficiency liposomal encapsulation, these results implicate TGs as components that are able to stabilize biological membrane transitions involving a changing interfacial area and curvature. This role for TGs may be of use in the formulation of drug delivery systems as well as in the investigation of membrane transitions in life sciences.


Assuntos
Glicerol , Fosfolipídeos , Triglicerídeos/química , Membrana Celular , Preparações Farmacêuticas/química , Solventes/química
20.
Food Chem ; 439: 138066, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38035493

RESUMO

The complex crystal structure of coca butter (CB) is responsible for the unique melting behavior, surface gloss, and mechanical properties of chocolate. While most studies concentrated on the crystalline state of CB, few studied the isotropic liquid state, which has a major impact on the crystallization process and the characteristics of the resulting crystals. In this study, the molecular organizations of the main CB triacylglycerols (TAGs; 1,3-dipalmitoyl-2-oleoylglycerol, palmitoyl-oleoyl-stearoylglycerol, POS, and 1,3-distearoyl-2-oleoylglycerol) were studied. The findings revealed the tunning-fork (Tf) conformation, commonly found in the crystalline state, is the least abundant in the isotropic liquid state of CB and pure TAGs. Notably, POS was found to interact with itself in CB, while its molecules with Tf conformation, although in small amounts in the mixture, tend to pair with each other at lower temperatures. These results highlight the significance of POS in CB crystallization and provide insights for developing CB alternatives.


Assuntos
Cacau , Coca , Cocaína , Gorduras na Dieta/análise , Triglicerídeos/química , Cristalização , Cacau/química
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