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Previous RS5 (type 5 resistant starch) research has significantly broadened starch use and benefited society, yet the effects of the molecular weight of amylose on RS5 remain underexplored. In this study, amyloses with different molecular weights were complexed with caproic acid (C6), lauric acid (C12), and stearic acid (C18) to observe the effects of the molecular weight of amylose on the structure and in vitro digestive properties of RS5. Gel permeation chromatography revealed that the peak average molecular weight (Mp) values of high-amylose cornstarch NF-CGK (CGK), high-amylose cornstarch obtained via cornstarch via autoclave (high temperature and high pressure)-cooling combined pullulanase enzymatic hydrolysis (CTE), and high-amylose cornstarch NF-G370 (HCK) were 21,282, 171,537, and 188,084 before fatty acid complexation, respectively. Additionally, their weight average molecular weight (Mw) values of 32,429, 327,344, and 410,610 and hydrolysis rates of 58.12 %, 86.77 %, and 64.58 %, respectively. The hydrolysis rate of low-Mw amylose (GCK) complexes with fatty acids was lower than that of HCK and CTE starch-lipid complexes. However, HCK and CTE having similar molecular weights, there was no significant difference in the hydrolysis rate of starch-lipid complexes. X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and complexing index analyses confirmed the formation of these complexes. This study proposed the mechanism of RS5 formation and provided guidance for its future development., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

To provide a theoretical basis for the quality improvement of plant protein-based meat substitutes with lipids, the interactions between pea protein and fatty acids (stearic, oleic and linoleic acids) and the effect on protein conformational changes during high-moisture extrusion (HME) processing were investigated using a dead-stop operation. The surface hydrophobicity analysis and Fourier transform infrared spectroscopy results revealed that the fatty acids induced the exposure of hydrophobic groups in the pea proteins, weakened hydrogen bonds, affected the aggregation of legumin subunits and promoted the conversion of α-helix and β-sheet structures to β-turn and random coil during HME processing. In the die, unsaturated fatty acids limited the refolding of protein chains and covalent interactions between proteins. Micromorphology analysis indicated that the coalescence of oleic and linoleic acids in the cooling zone hindered the formation of anisotropic structures while stearic acid promoted the formation of fibrous structures by enhanced disulfide bonds., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Here, Cotton fabric was functionalized via hybrid coating including 2D MgAl LDH (layered double hydroxide) and SA (stearic acid). The urea hydrolysis was employed for construction of vertically aligned LDH on surface of cellulose fibers under hydrothermal condition. The in situ formation mechanism of LDH on cotton surface was nucleation, growth, and interaction with activated cellulose chains. The partial cellulose ionization in the alkaline solution led to nucleophilic behavior towards electron deficient atom. The effect of different ageing, synthesis temperature, and amount of SA were investigated and optimized at 100 °C for 24 h with 0.05 M. The superhydrophobic surface architecture of treated cotton with hierarchical micro/nanostructure was inspired from the Taro leaf structure with continuous contact line presented WCA of 154 ° and CAH of 9 °. The Cotton@LDH@SA exhibited efficient oil/water separation after several washes (>90%) with good stain resistant. Also, the physico-mechanical properties were studied., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

With an aim to prepare the functional chocolate, corn oil was used as the base oil and β-sitosterol was combined with oryzanol/stearic acid/lecithin to prepare respective oleogels (GO, SO, and LO). Oleogels (12%) were prepared by adding compound oleogelators at different ratios [GO-2:3, SO-1:4, and LO-4:1 (w/w)] in corn oil. The microstructure, interaction, thermodynamic, crystalline, and rheological behavior of formulated oleogels were studied by microscopic observation, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and rotational rheometer, respectively. The results showed that GO had the strongest gel forming ability and the densest gel crystallization network. Moreover, chocolate prepared with GO (cocoa butter and oleogels-1:1) had the similar texture, crystal structure, rheological, and sensory properties to that of dark chocolate. This study provides the possibility for the wider application of oleogel prepared with lower saturated and trans-fatty acids in the chocolate industry., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Arabinoxylan (AX) and cellulose were extracted from wheat straw, whereas starch was extracted from potato peel. Thereafter, cellulose and starch were esterified with lauric, myristic, palmitic and stearic acids to prepare corresponding cellulose (CFAs) and starch fatty acid esters (SFAs) with DS 2.1-2.8. XRD study revealed remarkable loss of crystallinity in cellulose and starch due to fatty acid esterification. The addition of palmitate and stearate esters of cellulose and starch to AX formed laminar film microstructures which limited water vapor permeability whereas films prepared by blending AX with laurate and myristate esters of starch and cellulose were less effective as water vapor barrier due to their non-layer microstructures. The laminar structures also resulted significant reduction in mechanical strength of the composite films. Furthermore, all AX-CFAs and AX-SFAs films were thermally more stable than native composite films. These films might be used to produce industrially useful coating material for food products., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Interesterification is widely employed as an effective technique to modify oils and fats. This study utilizes palm-based oil (palm olein: palm kernel oil: palm stearin, 5:3:2, w/w/w) as the raw material for the interesterification process performed in a pilot-scale packed bed reactor. Enzymatic interesterification (EIE) was catalyzed by Lipozyme TL IM (813.0 g) at 60℃ with reaction flow rate of 100 mL/min. Chemical interesterification (CIE) was catalyzed using sodium methoxide (0.3 wt%) as catalyst at 105 °C for 30 min. The results showed that the EIE fats had lower solid fat content tendency compared to that of CIE fats. The crystallization onset temperature was higher in EIE fats (23.09℃) compared to that of CIE (19.08℃). The results were consistent with the crystallization kinetics whereby the Avrami K constants of EIE fats were higher than that of CIE fats at various temperatures, indicating rapid crystallization and instant nucleation. Linear growth mechanism was dominant and the crystals formed were smaller in size as observed using polarized light microscope. The interesterified fats exhibited the presence of β and β'-crystals. While most of the tocopherol content was retained after EIE (386.18 ug/g), the molecular distillation process reduced the tocopherol concentration (110.01 ug/g) which consequently affected the oxidative stability. The findings in this work contribute to the fundamental understanding on the differences between CIE and EIE fats and provides data to support the preparation of modified fats via EIE that shows great potential as a controllable technique for industrialization., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, cocoa butter equivalents (CBEs) were prepared through enzymatic interesterification of palm mid-fraction (PMF) with stearic acid (SA). The reaction process parameters were experimented and the performance of the product was analysed. PMF and stearic acid (at a mass ratio of 1:2) were catalysed by 80 g kg -1 enzyme loading of Lipozyme RM IM fromRhizomucor mieheiat 60 °C for 120 min. The yield of the CBE product was more than 92%, and the CBE resembled cocoa butter (CB) in terms of its triacylglycerol composition. The hardness of the CBE product was higher than that of CB at different storage temperatures, but this difference was not obvious at 25 °C. The polymorphic structures and SFC curve of the CBE were similar to those of the CB. In addition, the CBE could be mixed with CB in any ratio without an obvious eutectic phenomena. Up to 40% CBE could be added to CB without significantly affecting the thermodynamic properties of CB. Thus, replacing CB with the CBE product is feasible., (Copyright © 2020. Published by Elsevier Ltd.)

This paper reports an experimental study of the formation and properties of dark chocolate prepared using novel CB alternative fats (CBAs): symmetric (OS at O) and asymmetric (S at S at O) mixed-acid triacylglycerols (TAGs), in which Sat and O represent saturated fatty acids (stearic:S + palmitic:P) and oleic acid moieties, respectively. It was found that the ternary fat mixtures of CB/S at S at O/OS at O with a ratio of CB/(S at S at O + OS at O) of 1:1 formed the most stable β-form of the double chain length (DCL) structure (β-2), which revealed sufficient hardness and sharp melting profiles around body temperature without tempering processes. Fat bloom formation was not observed in dark chocolate with CBAs at ratios of CB/S at S at O/OS at O of 50/20/30-50/0/50 during the one-year storage test at temperatures between 15 °C and 30 °C. Overall, the present study has shown that fat mixtures made of CB/S at S at O/OS at O, which are rich in oleic acid moieties, can be employed as a cocoa butter equivalent (CBE) fat without tempering procedures., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Vitexin of Ficus deltoidea exhibits intestinal α-glucosidase inhibitory and blood glucose lowering effects. This study designs oral intestinal-specific alginate nanoparticulate system of vitexin. Nanospray-dried alginate, alginate/stearic acid and alginate-C18 conjugate nanoparticles were prepared. Stearic acid was adopted to hydrophobize the matrix and minimize premature vitexin release in stomach, whereas C-18 conjugate as immobilized fatty acid to sustain hydrophobic effect and drug release. Nanoparticles were compacted with polyethylene glycol (PEG 3000, 10,000 and 20,000). The physicochemical, drug release, in vivo blood glucose lowering and intestinal vitexin content of nanoparticles and compact were determined. Hydrophobization of alginate nanoparticles promoted premature vitexin release. Compaction of nanoparticles with PEG minimized vitexin release in the stomach, with stearic acid loaded nanoparticles exhibiting a higher vitexin release in the intestine. The introduction of stearic acid reduced vitexin-alginate interaction, conferred alginate-stearic acid mismatch, and dispersive stearic acid-induced particle breakdown with intestinal vitexin release. Use of PEG 10,000 in compaction brought about PEG-nanoparticles interaction that negated initial vitexin release. The PEG dissolution in intestinal phase subsequently enabled particle breakdown and vitexin release. The PEG compacted nanoparticles exhibited oral intestinal-specific vitexin release, with positive blood glucose lowering and enhanced intestinal vitexin content in vivo., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Glycerol monosterate (GMS) and stearic acid (SA) share a similar carbon chain structure while SA has a carboxyl head group and GMS has two free hydroxyl groups. The current research focuses on the relationship between GMS and SA chemical structure, nano and mesoscale crystal structure, and the oleogel macroscopic characteristics. Molecular analysis revealed the formation of different types of hydrogen bonds, which disappear upon temperature increase at different temperatures. Nano-structural analysis exhibited tight and ordered lamellar structures for SA compared with loosely packed short lamellar structures in GMS oleogel, presumably due to its larger hydrophilic head group. Microstructure imaging revealed ordered anisotropically orientated needle-like crystals in SA and isotopically ordered braid-like crystals in GMS oleogels. Mechanical analysis revealed that gel strength is enhanced when crystal structure is isotropically oriented, similar behavior seen is composite materials, where the structuring agent crystals behave like a reinforcing agent within the oil matrix., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Herein, we introduce a novel amphiphilic bioconjugate (INU-F68-SA), synthesized by functionalization of pluronic F68 with a polysaccharide inulin (INU) and a lipid stearic acid (SA). The synthesis of INU-F68-SA was confirmed by FTIR and 1 H-NMR analysis. INU-F68-SA can self-assemble into nanomicelles and therefore, its application in delivering of hydrophobic resveratrol (RSV) was investigated. The RSV-loaded INU-F68-SA nanomicelles (RSNM) had about 172 nm size, spherical shape, 0.237 polydispersity index, and -18 mV zeta potential. More importantly, the RSNM showed high drug entrapment efficiency, controlled drug release and protection of drug during storage. The RSNM significantly enhanced the cytotoxicity of RSV against colorectal cancer cells by inducing apoptosis and changing mitochondrial membrane potential. Further, in-vivo pharmacokinetic experiment indicated an improvement in pharmacokinetics of RSV after administering as RSNM. Thus, the use of self-assembled nanomicelles of amphiphilic INU-F68-SA bioconjugate could be a better alternative to overcome the poor in-vitro and in-vivo performance of RSV., (Copyright © 2020. Published by Elsevier Ltd.)

Functional modifications of starch, such as paste properties, retrogradation, water absorption indexes, solubility, and swelling capacity, are induced by the amylose-lipid complex. This research comprehends the study of functional properties of extruded maize starch mixed with fatty acids (stearic acid, oleic acid, and maize oil) and the formation of amylose-lipid complexes. Maize starch with lipids (5 or 10 %), moisture (35 %) was extruded (single screw). Starch granule was modified by extrusion, to a lesser extent at 10 % of lipids, especially stearic acid, which covers starch granule surface. Viscosity decreased meaningfully with stearic acid addition. DSC showed both starch gelatinization enthalpy and amylose-lipid complex enthalpy for stearic or oleic acid, but it was just the first enthalpy for maize oil. X-ray diffraction showed orthorhombic crystals with or without the presence of lipids. Our results indicated that stearic acid yielded the highest amount of amylose-lipid complexes., Competing Interests: Declaration of Competing Interest Authors declare that they do not have any conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Currently, the development of polysaccharide, especially chitosan (CS), based drug delivery system to afford magnetic resonance imaging (MRI) guided theranostic cancer therapy remains largely unexplored. Herein, we successfully developed a CS derived polymer (Gd-CS-OA) through chemical conjugation of CS, octadecanoic acid (OA) and gadopentetic acid (GA). After self-assemble into glycolipid nanoparticles to loaded chlorin e6 (Ce6), the resulted Gd-CS-OA/Ce6 was able to realize MRI guided photodynamic therapy (PDT) of cancer. Our results revealed that Gd-CS-OA was able to increase the MRI sensitivity as compared to Gd-DTPA with decent residence time and preferable excretion behavior in vivo. Moreover, the Gd-CS-OA/Ce6 showed negligible hemolysis, satisfactory ROS generation and stability in physiological environments with preferable cellular uptake and enhanced in vitro cytotoxicity (through elevated ROS generation) on 4T1 cells. Most importantly, Gd-CS-OA/Ce6 demonstrated promising in vivo tumor targetability (enhanced penetration and retention effect) and powerful MRI guided tumor ablation through PDT on in situ 4T1 tumor model., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Structuring of vegetable oils has potential application in food, pharmaceutical and cosmetic products. In this study, structuring effects of stearic acid derivatives on sunflower seed oil were systematically investigated by experimental and molecular simulation methods. Stearic acid (SA), 12-hydroxy stearic acid (HSA) and 2-hydroxyethyl stearate (HES) were able to structure sunflower seed oil, among which the structuring ability of HES was reported for the first time. The oleogel formed with HSA exhibited good mechanical properties (such as hardness, fracturability, adhesiveness, chewiness and storage modulus), which coincided with its highest solid fat content and degree of crystallinity. Oleogels containing SA and HES showed similar mechanical properties. Both the molecular dynamics (MD) simulation and independent gradient model (IGM) confirmed that the HSA dimer possessed the strongest interaction during the self-assembly process while the dimers of HES and SA had similar interactions, which could explain their structuring performance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aim of this study was to introduce Pickering emulsions stabilized by chitosan (CS)-stearic acid (SA) nanogels incoporating clove essential oil (CEO) as a new way to enrich mayonnaise with fish oil. Firstly, fish oil-in-water Pickering emulsion was prepared, which the most stability of emulsion was achived at 2 % (w/w) CS-SA nanogels and 60 % (w/w) fish oil. Then, the fish oil-in-water Pickering emulsions stabilized with 2 % CS-SA nanogels as well as 2 % CS-SA nanogels incorporating CEO were used in formulation of mayonnaise. The results showed that the use of fish oil in the form of emulsion stabilized with CS-SA nanogels increased the oxidative stability of mayonnaise. Moreover, rheological studies indicated that the use of CS-SA nanogels could increase the elasticity of mayonnaise, which higher elasticity was observed about mayonnaise containing CS-SA nanogels incorporating CEO. Overall, CS-SA nanogels incorporating CEO can be used for increasing gel-like structure of the fish-oil-enriched mayonnaise., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This study describes the determination of lead at trace levels by slotted quartz tube flame atomic absorption spectrophotometry (SQT-FAAS) after preconcentration by the help of stearic acid coated magnetic nanoparticle (SAC-MNPs) based sonication assisted dispersive solid phase extraction (SA-DSPE). SAC-MNPs were used due to their easy separation advantages by the application of external magnetic field. All extraction parameters were optimized by response surface methodology based experimental design. The experimented data was evaluated by the analysis of variance. Under the optimum conditions, about 31 folds enhancement in detection power was obtained over the conventional FAAS. The recovery results obtained for samples spiked at 60 and 120 ng mL -1 were 106.6 and 102.6%, respectively, validating the method as accurate and applicable to the red pepper matrix. The percent relative standard deviations of the results were under 5.0% even at low concentrations that established high precision for replicate extractions and instrumental readings., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Chitosan oligosaccharide-valylvaline-stearic acid (CSO-VV-SA) nanomicelles were designed for topical ocular drug delivery, based on peptide transporter-1 (PepT-1) active targeting. Hydrogenated castor oil-40/octoxynol-40 (HCO-40/OC-40) mixed nanomicelles were also prepared according to Cequa, just approved by FDA. Both nanomicelles produced no significant cytotoxicity and difference in human corneal epithelial cells (HCEpiC) and human conjunctival epithelial cells (HConEpiC). The active transport of CSO-VV-SA nanomicelles by PepT-1 was illustrated in the inhibitory test. Ex vivo fluorescence images of frozen sections indicated that the nanomicelles entered the posterior segment mainly through conjunctival route. In vivo precorneal retention study suggested dexamethasone from both nanomicelles could be detected for more than 3 h in rabbit tears. In vivo distribution evaluation of rabbits' eyes showed the delivering efficiency of CSO-VV-SA nanomicelles was not inferior to that of HCO-40/OC-40 mixed nanomicelles. These findings indicated that CSO-VV-SA nanomicelles could become promising candidates for further clinical application., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Although storage temperature is important for partial coalescence, the literature is scant on exploring the partial coalescence behavior between refrigerated and room temperature storage. In this study, comparison of the partial coalescence behavior between 4 and 20 °C was investigated towards corresponding oil-in-water emulsions, and subsequently towards the ultimate properties of the aerated colloidal system. As expected, compared to the value of Avrami constant (K) at 20 °C, the value of palm kernel stearin (PKS85) and mixtures of PKS85 and glycerol monostearate (PKS85-GMS) obtained at 4 °C increased by 22 and 14 times, respectively. PKS85 and PKS85-GMS displayed the needlelike appearance (N-type crystal) with a little layer crystal (L-type crystal) at 4 °C and spherical shape formed by L-type crystal along with granular crystal at 20 °C. Interestingly, several unstable air bubbles with irregularly-shape were observed in the aerated emulsions at 20 °C, while these emulsions at 4 °C displayed numerous rounded and uniform air bubbles with glossy surface. This was attributed to the sufficient stiff needle crystals at 4 °C, facilitating the coalescence of fat globules via liquid fat bridges, further forming a rigid crystal-based network and trapping the air bubbles. Therefore, our findings gained an insight into the partial coalescence behavior in emulsion, providing theoretical support for designing and optimizing the production process of foam structure products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Double (W1/O/W2) emulsions of 0.8 %wt PGPR-0.25 %wt BC-1 %wt WPI and NaCl (1.6-8 %wt) were characterized regarding their microstructure, droplet size, stability and viscosity. Droplet size increased with salt concentration. Salt addition at 4-5% wt limited the instability rate. Viscosity increased with NaCl concentration up to 4.8 %wt, above which it decreased. Eventually, the emulsion with 4.3 %wt salt was selected for catechin incorporation. In order to increase its antioxidant activity, Epigallocatechin Gallate (EGCG) was esterified with stearic acid. Esterification was partial and a mixture of esters was obtained. Both EGCG and its esterified derivatives were incorporated in the double emulsion. Storage reduced encapsulation. Encapsulation efficiency was reduced in the order "EGCG in the W1 phase" emulsion > "EGCG in the O phase" emulsion > "esterified EGCG in the W1 phase" emulsion. The presence of both catechins did not have a great effect on retarding emulsion oxidation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study determines the effects of stearic acid and gamma irradiation, alone and in combination, on properties of amylose-lipid nanomaterials from pasted high amylose maize starch (HAMS) with and without alpha amylase hydrolysis. HAMS was incorporated with stearic acid (0, 1.5% and 5%, w/w), irradiated at 0, 30 and 60 kGy and pasted under pressure in a rheometer. Isolated materials after thermostable alpha amylase or hot water washing were freeze-dried and characterised using differential scanning calorimetry (DSC), X-ray diffraction (XRD), Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). The isolated materials contain amylose-lipid complexes (ALCs) as determined by DSC and XRD. Pasting of gamma irradiated HAMS produced type I ALCs, whereas that for un-irradiated HAMS produced type II ALCs. The ALCs occurred at nanoscale with sizes ranging from 10 to 110 nm as observed with AFM and TEM. Tailor-made ALCs nanomaterials can be produced from HAMS (with and without added stearic acid)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

To develop a carrier for targeted drug delivery and triggered drug release in a reducing-tumor environment, reduction-sensitive hyaluronic acid-g-stearic acid (HCS) micelles were synthesized using a coupling agent. The HCS 40% was shown to have a more compact particle size than HCS 20% and the particle size of doxorubicin (DOX)-loaded HCS (HCSD) was increased relative to that of HCS micelles. The behavior of DOX release from HCSD showed that DOX was rapidly released in GSH (10 mM) solution. The site-specific targeting effect of HCSD nanoparticles was investigated by cellular uptake and competition assay at HCT116 and CT26 cell lines. An in vivo study of HCSD revealed that tumor suppression and site-specific targeted delivery of HCSD nanoparticles in HCT116-xenografted tumors were more superb than in the CT26-xenografted tumor. These results suggest that HCSD nanoparticles can be expected to have high therapeutic efficacy because they enable targeted drug delivery and rapid drug release., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The effect of wheat straw arabinoxylan (AX) and β-glucan stearic acid ester (SABG) composite coating on the quality and storage life of apple (Royal Delicious) was studied at 22 °C (±2) with relative humidity of 65% and 85% for 60 days. Fresh fruits were coated with surface coatings of AX-SABG, shellac in the concentration range of 1-4%. Application of both AX-SABG (1-4%) and shellac (1-4%) coatings was found to significantly reduce weight loss, respiration rate, fruit softening process, ripening index, color degradation and polyphenol oxidase activity compared to control during the storage period of more than 30 days. However, an AX-SABG coating was more effective in reducing fruit decay and loss of aroma volatiles followed by shellac coated apples; the un-coated apples being showing maximum quality deterioration. These findings confirmed the potential benefits of applying AX-SABG coating to extend the shelf life and quality of apples especially during transportation and storage., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Implementing ω-3 polyunsaturated fatty acids (ω-3 PUFA), naturally found in echium oil (EO), can highly improve the nutritional value of fortified foods. However, PUFA is prone to oxidation. In this study, the role of nanostructured lipid carriers incorporated into whey protein isolate (WPI)-stabilized EO droplets in oil-in-water emulsions was analyzed. Lipid carriers such as lauric (LA), palmitic (PA), and stearic (SA) acids were used. The results reveal that lipid carriers, especially LA, improve the physical stability of these droplets by decreasing their particle size by decreasing the number of surface pores; shown by SEM images and XRD data. Rheological data further show that the emulsions incorporated with LA had higher viscosity and there was also a crossover shift to lower strains in the G'-G″ curve of the emulsions incorporating LA. TBARS assay indicated that LA was more effective in protecting EO against oxidation than both palmitic and stearic acids., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The aims of this research were to conjugate chitosan (CT) with stearic acid (SA) and gallic acid (GA), and apply the modified chitosan to stabilize labile aroma compounds such as allyl isothiocyanate (AITC) and limonene in oil-in-water emulsions. Generally, the antioxidant activity of CT-SA-GA increased as the GA content in the conjugate increased. In most assays, GA had a lower IC 50 value than that of CT-SA-GA; however, CT-SA-GA exhibited better performance than GA in the Fe 2+ -chelating activity. In accelerated tests (heating or illumination) for evaluating the chemical stability of AITC and limonene during storage, CT-SA and CT-SA-GA were used to prepare AITC and limonene O/W emulsions, respectively. Tween 80 and Span 80 (T-S-80), an emulsifier mixture, were used as a control in both emulsions for comparison. The results show that CT-SA or CT-SA-GA could protect AITC or limonene from degradation or oxidation more effectively than T-S-80., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The effect of free fatty acids with different chain lengths or unsaturation degree on anhydrous milk fat (AMF) crystallization was evaluated. The impact of esterification was also studied using three triglycerides. Melted blends containing the additives at concentrations lower than 12wt.% were quenched at 25°C and isothermal crystallization was monitored by pulsed low-resolution nuclear magnetic resonance. In parallel, polarized light microscopy was used to observe the microstructure. Compounds based on long chain saturated fatty acids, i.e. palmitic, stearic, eicosanoic acids, tripalmitin and tristearin accelerated crystallization. Conversely, propanoic, hexanoic and oleic acids slowed down the process, while triacetin had no impact. Interestingly, above a critical concentration, the addition of palmitic, stearic or eicosanoic acids caused a transition from a one-step to two-step process. Gompertz model was used to fit the experimental data and to assess the influence of the molecular properties of the additives on the kinetic parameters., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Cellulose oligomers are water-soluble, on the contrary to cellulose, which greatly increase their application range. In this study, cellulose oligomers were obtained from the acidic hydrolysis of cellulose with phosphoric acid. The global yield in water-soluble oligomers was around 23% with polymerization degree (DP) ranging from 1 to 12. The cellulose oligomers DP distribution was successfully reduced by differential solubilisation in methanol as one of the goals of this work was to avoid the use of a time-consuming full chromatographic separation. The methanol-soluble oligomers were mainly low DP (≤3). The oligomers of higher molar mass, composed of 42% of cellotetraose and 36% of cellopentaose, were then functionalized and coupled with stearic acid through azide-alkyne click chemistry to obtain amphiphilic compounds. The self-assembly of these new bio-based compounds was finally investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM) and their critical micellar concentration (CMC) was found to be in the same range as alkylmaltosides and alkylglucosides., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Cellulose esters with long carbon side chains (e.g. stearate) were produced via a homogenous reaction in ionic liquids. The degree of substitution was calculated to approximately 2. The melt rheology was studied for the pure cellulose esters but also combinations of the esters and polypropylene to study the processability of a blended composite material. It was shown that the compatibility between the two components was weak, which resulted in a phase-separated composite material. The morphology and permeability of water and oleic acid of the composite films were studied and it was shown that the water permeability decreased upon addition of the cellulose ester to the polymer. The permeability of oleic acid was however unchanged, which is most probable a result of high solubility in the cellulose ester rich domains of the composites. Also, the following hypothesis is stated: cellulose stearate influence the polypropylene crystallization process by decreasing the size of spherulites., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The present study aimed to develop and optimize the wax based floating sustained-release dispersion pellets for a weakly acidic hydrophilic drug protocatechuic acid to achieve prolonged gastric residence time and improved bioavailability. This low-density drug delivery system consisted of octadecanol/microcrystalline cellulose mixture matrix pellet cores prepared by extrusion-spheronization technique, coated with drug/ethyl cellulose 100cp solid dispersion using single-step fluid-bed coating method. The formulation-optimized pellets could maintain excellent floating state without lag time and sustain the drug release efficiently for 12h based on non-Fickian transport mechanism. Observed by SEM, the optimized pellet was the dispersion-layered spherical structure containing a compact inner core. DSC, XRD and FTIR analysis revealed drug was uniformly dispersed in the amorphous molecule form and had no significant physicochemical interactions with the polymer dispersion carrier. The stability study of the resultant pellets further proved the rationality and integrity of the developed formulation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Consumer concerns to synthetic chemicals have led to strong preference for 'clean' label starches. Lipid and hydrocolloids are food friendly chemicals. This study determines the effects of stearic acid and xanthan gum alone and in combination on the functionality of maize, wheat, teff and cassava starches. An increase in viscosity was observed for all starches with stearic acid and xanthan gum compared to the controls with cassava having the least increase. A further increase in viscosity was observed for the cereal starches with combination of stearic acid and xanthan gum. Stearic acid reduced retrogradation, resulting in soft textured pastes. Combination of stearic acid and xanthan gum reduced the formation of type IIb amylose-lipid complexes, syneresis, and hysteresis in cereal starches compared to stearic acid alone. A combination of stearic acid and xanthan gum produce higher viscosity non-gelling starches and xanthan gum addition increases physical stability to freezing and better structural recovery after shear., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this work, polypropylene/thermoplastic starch (PP/TPS) blends were prepared as an alternative material to use in disposable packaging, reducing the negative polymeric environmental impact. Unfortunately, this material displays morphological characteristics typical of immiscible polymer blends and a compatibilizer agent is needed. Three different carboxyl acids: myristic (C14), palmitic (C16) and stearic acids (C18) were used as natural compatibilizer agent (NCA). The effects of NCA on the mechanical, physical, thermal and morphological properties of PP/TPS blends were investigated and compared against PP/TPS with and without PP-grafted maleic anhydride (PPgMA). When compared to PP/TPS, blends with C18, PPgMA and C14 presented an improvement of 25, 22 and 17% in tensile strength at break and of 180, 194 and 259% in elongation at break, respectively. The highest increase, 54%, in the impact strength was achieved with C14 incorporation. Improvements could be seen, through scanning electron microscopy (SEM) images, in the compatibility between the immiscible components by acids incorporation. These results showed that carboxylic acids, specifically C14, could be used as compatibilizer agent and could substitute PPgMA., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The effects of ultrasound treatment (UT) on the properties of methylcellulose (MC)/stearic acid (SA) blending films were studied. Film-forming emulsions were prepared with different UT conditions and characterized with respect to viscosity. The lipid aggregation and distribution in the blending dispersions were studied by the micrographs of Transmission Electron Microscopy (TEM). The micrographs of both surface and cross-section of the films were observed by scanning electron microscope (SEM) and the tensile strength (TS), elongation at break (E), water vapor permeability (WVP) and contact angles of the resulting films were determined as well. The intensification of the UT condition led to a decrease of viscosity of the MC-SA blending emulsions, a more homogeneous lipid distribution and a denser internal microstructure of the resulting films. UT exposure affected the mechanical, moisture barrier and surface hydrophobic properties. The optimal values of both TS and E was obtained from the sample treated for 10min and 180W power, while the sample treated for 10min and 270W presented the lowest value of WVP. However, an excessive exposure of UT led to a decrease of the mechanical and moisture barrier performance. By observing and analyzing the SEM graphs and the contact angles of the film surfaces, it was found that UT within the appropriate bounds had a notably positive effect on improving the surface hydrophobic property of the MC-SA blending films., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The acylation of procyanidin B4 with a saturated fatty acid chloride containing 18 carbon atoms was studied in order to obtain procyanidin B4 3-O-di-stearic acid conjugate. This compound was structurally characterised by mass spectrometry and 1D and 2D NMR techniques. Derivatization of malvidin-3-glucoside using stearoyl chloride in acetonitrile was also performed yielding mono-, di- and tri-stearic ester derivatives. The novel derivatives obtained revealed significant antioxidant activity, although lower than the respective precursors. However, the chemical modification of anthocyanins and procyanidins (water soluble pigments) to more lipophilic compounds has the advantage of increased bioavailability in biological matrices, and to potentiate their application in food matrices and cosmetic products., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A series of moisture-resistant konjac glucomannan films were prepared by coating shellac/stearic acid emulsion on deacetylated konjac glucomannan films (dKGM). The effect of stearic acid content on structure and properties of the coated films were investigated by field emission scanning electron microscopy (FE SEM), Fourier transform infrared spectroscopy (FT-IR), ultraviolet spectroscopy (UV), water vapor permeability (WVP), water uptake, water contact angle, and tensile testing. The results revealed that shellac in the coating adhered intimately to the surface of dKGM film, and provided a substrate for the dispersion of stearic acid which played an important role in enhancement of the moisture barrier properties and mechanical properties of the coated films. The WVP of the coated films decreased from 2.63×10(-11) to 0.37×10(-11)g/(msPa) and the water contact angle increased from 68° to 101.2° when stearic acid content increased from 0wt% to 40wt%, showing the potential applications in food preservation., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The effect of structure creation and moisture content on the dielectric properties of amylose, amylopectin and amylose-stearic acid complexes is presented. Three dielectric features have been identified in these systems. At low temperature, a dipole relaxation process is observed which is assigned to the reorientation of the CH(2)OH group. At ambient temperatures, a thermally activated relaxation is assigned to liberation-local chain motion. In certain systems at high temperatures, a Maxwell Wagner Sillars process is observed associated with the heterogeneous nature of media and is ascribed to the gel structure in the amylose-stearic acid complex. The low temperature relaxation is sensitive to the moisture content, the water molecules being bound to the CH(2)OH groups and the activation energy being reduced as the water content is increased. Comparison of the relaxation observed in amylose and amylopectin indicates that chain branching increases the activation energy and inhibits the local reorientation motion of the chain backbone. The relative magnitude of the relaxation processes and their activation energies are discussed in term of the structure of the polymer backbone, the nature of the complex formed with stearic acid and the extent to which order is created by thermal treatment. This paper gives insight into the changes in amylose mobility accompanying the formation of the various complexes., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The physical and chemical parameters (melting point and saponification number), and the fraction of hydrocarbons, monoesters, acids and alcohols have been determined in 90 samples of Spanish commercial beeswax from Apis mellifera L. The adulteration with paraffins of different melting point, cow tallow, stearic acid, and carnauba wax were determined by HTGC-FID/MS detection, and the research was focussed mainly on paraffins and microcrystallines waxes. In general, the added adulterant can be identified by the presence of non-naturally beeswax components, and by the differences of values of selected components between pure and adulterated beeswax. The detection limits were determined using pure and adulterated beeswax with different amounts of added waxes (5%, 10%, 20% and 30%). Percentages higher than 1-5% of each adulterant can be detected in the mixtures. Paraffin waxes were confirmed in 33 of the 90 samples analysed at concentrations between 5% and 30%., (Copyright © 2011 Elsevier Ltd. All rights reserved.)