Structural characterization of amylose-long chain fatty acid complexes produced via the acidification method

Amylose molecular inclusion complexes, or V-amylose, have been studied as a possible nano-sized delivery system for unsaturated fatty acids. This study aimed to study three different structural levels of V-amylose produced via an acidification method. Molecular attributes were studied using XRD, DSC and ¹³C CP/MAS NMR, nanostructures using SAXS and AFM, and the microscopic level by SEM and AFM. ¹³C labeled fatty acids revealed head groups were entrapped in both COO- and COOH forms. SAXS data, showed that conjugated linoleic acid yield particles with the highest values for parameters like average crystalline lamellar thickness (φ = 0.46) and characteristic particle dimension (R_g = 1011). AFM revealed surface roughness increases from 7.72 ± 4.34 nm to 11.54 ± 6.05 nm during the formation of V-amylose. The insights described contribute to the understanding of V-amylose structure and help establish a model for V-amylose structure which may prospectively be used in the fabrication of a novel delivery system.     

Effects of long chain fatty acid unsaturation on the structure and controlled release properties of amylose complexes

The addition of functional long chain (LC) unsaturated fatty acids to foods is often hampered by their instability. This study aimed to probe the possibility of using molecular inclusion complexes formed by amylose, termed V-amylose, as a possible solution for the delivery of long chain (LC) fatty acids to the consumer. X-ray diffraction, light scattering and atomic force microscopy (AFM) were employed to study the micro- and nano-structure of V-amylose hosting LC fatty acids with different degrees of unsaturation. Additionally, enzymatic digestion tests were conducted to assess the release of the fatty acids from the complexes. X-ray diffraction confirmed the formation of V-amylose while light scattering measurements, and the AFM images revealed that increased fatty acid unsaturation lead to the formation of bigger and more disperse particle populations. Enzymatic digestion tests with mammalian pancreatin illustrated the control over guest release which is induced by enzymatic hydrolysis. In conclusion, this study demonstrates that guest chemistry affects some of the functional properties of V-amylose for the delivery of LC fatty acids.     

Molecular encapsulation of linoleic and linolenic acids by amylose using hydrothermal and high-pressure treatments

The health benefits of polyunsaturated fatty acids are well known, however their fragility is a drawback as it leads to their degradation. The objective of this study was to develop innovative assemblies, using the capacity of starch to encapsulate small molecules, for the protection of polyunsaturated fatty acids like linoleic acid and linolenic acid. These assemblies were produced by hydrothermal treatment, and by high-pressure treatment (20 min at 500 MPa at a temperature of 40 °C). They were then analyzed and characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), nuclear magnetic resonance (¹³C CP/MAS NMR) and a heating cell in XRD. The results showed that amylose–ligand complexes were formed during both treatments and two crystalline types V_6I and V_6II were obtained. The techniques used show excellent complementarities in the determination of important structural features such as crystalline type, helical conformation and nature of the inclusion.     

The Impact of Thermal Events on Amylose‐Fatty Acid Complexes

The molecular behavior of amylose‐lipid complexes was studied using differential scanning calorimetry. rapid viscoanalysis and texture analysis methods. Three amyloses were fractionated, one each from regular, 50% amylose and 70% amylose corn starches. High performance size exclusion chromatography, coupled with multiple angle laser light scattering, was used to determine amylose molecular weight profiles; fractions differed statistically (P>0.05) in their z‐average molecular weights (M_z). Each amylose fraction was complexed with five different fatty acids. After 12 days of storage, amylose‐lipid complexes had recrystallization percentages ranging from 42.7 to 98.2%. Cohesiveness (r = ‐0.84) and adhesiveness (r = ‐0.75) decreased with increasing M_z of amyloses (P>0.05). An inverse relationship was obtained between fatty acid chain length and percent recrystallization (r = ‐0.84, P>0.05). Percent recrystallization decreased when fatty acid chain length increased from C16:0 to C18:0. All complex samples, when adjusted to an equal total starch basis, had decreased viscosities when pasted compared to their native starch or amylose counterparts. Shear thinning of complexes increased with increasing molecular weight (M_z) of amyloses (r = 0.71, P>0.05). Lower recrystallization rates and decreased viscosity properties could be accomplished complexing by amylose and fatty acids.     

脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物结构和热性能的影响

本文研究了脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物热性能、微观结构、粒径分布及Zeta电位的影响。结果表明,高直链玉米淀粉与脂肪酸形成复合物后热稳定性降低,且复合物的热稳定性随脂肪酸不饱和度的增加而降低;高直链玉米淀粉与脂肪酸形成复合物的结晶结构为V型,结晶度随着不饱和度的增加而减小;高直链玉米淀粉-脂肪酸复合物有两种存在形式,分别为颗粒表面凸起的球晶和嵌在颗粒表面的层状或絮状结构,后者存在形式随脂肪酸中双键个数的增加而减少;高直链玉米淀粉与脂肪酸形成复合物后淀粉颗粒变小,分散液稳定性增加。总之,脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物的结构和热性能具有明显影响。     

Physical and chemical characteristics of donkey meat from Martina Franca breed

The rheological and chemical characteristics of meat obtained from 12 Martina Franca donkey males, slaughtered at 14 months of age and a mean final body weight of 169 kg were determined. Meat samples were taken four days post mortem from muscles Longissimus thoracis et lumborum and Biceps femoris, colorimetric parameters were measured to determine L^* (lightness), a^* (redness), b^* (yellowness) and chroma. The Longissimus was significantly lighter (P < 0.05) compared to the Biceps femoris, with L^* indexes of 35.86 and 31.34, respectively. Fatty acid composition of the intramuscular fat showed a high content of polyunsaturated fatty acids (PUFAs) in both muscles, respectively 25.16 g/100 g total fatty acids in the Longissimus and 24.97 g/100 g total fatty acids in the Biceps femoris; oleic acid and palmitic acid were the two most abundant fatty acids in both muscles. The percentages of essential amino acids were higher in both muscles compared with the total amino acid content, respectively 52.88% in the Longissimus, and 51.26% in the Biceps femoris. The high level of unsaturation of the intramuscular fat resulted in a high ratio of unsaturated to saturated fat, and the total amount of essential amino acids, exceeding 50% of the total amino acids showed that donkey meat from a health point of view is a good alternative to traditional red meats.     

The Influence of Thiocyanate Ions on the Formation of the Starch‐Iodine Complex

The redox reaction between thiocyanate and iodine species present in an aqueous solution of KI results in the formation of thiocyanogen, (SCN)₂. This reaction interferes with the formation of inclusion complexes of a potato amylose with iodine species such as I₃^‐ and I₅^‐. As these ions react with thiocyanate ions (SCN^‐) the blue colour of the amylose‐iodine complex diminishes. The rate of this decrease depends upon the concentration of both the SCN^‐ and the iodine, and appears to follow pseudo‐second order kinetics. Using a UV/visible spectrophotometer the reaction of iodine with KSCN can be followed, with or without amylose, and shows a lowering in concentration of iodine species absorbing at 290–300 nm, together with a lowering in absorbance at 630 nm, due to a lesser amount of the amylose‐iodine complex. Interference with iodine complex formation was also noted with a potato amylopectin. The technique provides the basis for the study of other reactions of iodine such as that with selenocyanate (SeCN^‐).     

Evaluation of Fatty Acid Profile of Wagyu Beef by ATR-FTIR Spectroscopy

Japanese black Wagyu beef has its characteristics of fatty well-marbled texture, flavor, and tenderness which are affected by fatty acid composition. The aim of this study was to develop an analytical method for evaluating the fatty acid profile of Wagyu beef by Fourier transform infrared (FTIR) spectroscopy. In the current study, attenuated total reflection–FTIR (ATR-FTIR) spectroscopy and gas chromatography (GC) were applied to the fat tissues, and the solvent-extracted fats which were sampled from subcutaneous, inter- and intramuscular fat tissues. Results of GC analysis showed that monounsaturated fatty acids (MUFA) content became larger in the order of intramuscular, intermuscular, and subcutaneous fats, and saturated fatty acids (SFA) became smaller in the same order. Subcutaneous fat could be discriminated from inter- and intramuscular fats on the basis of fatty acid composition by principal component analysis. The ATR-FTIR analysis revealed that the shift of the peak positions of alkene C–H stretching vibration at around 3,006 cm⁻¹ occurred depending on the unsaturation degree of fatty acids in beef fat. Partial least squares (PLS) regression analysis with leave-one-out cross-validation was applied to the combined regions of 2,800–3,050 and 1,000–1,500 cm⁻¹ for the fat tissues and the extracted fats. The correlation coefficients of the PLS validation models predicting the content of the MUFA and SFA for solvent-extracted fats were higher than those for fat tissues, and the coefficients (R ²) of determination more than 0.873 were obtained for solvent-extracted fats and 0.522 for fat tissues.     

Bioactive lipids and fatty acids profile of Cistanche phelypaea

Oil extracted from the wild plant of Cistanche phelypaea was analyzed for its fatty acid, sterol, hydrocarbon and tocopherol contents. Total lipids (TL) content was 10 g/kg (on dry weight basis). The majority of fatty acids were of the unsaturated type (50.4 % of total fatty acids), while the saturated (mainly palmitic acid) were about 43.2 % of the total fatty acids. Oleic acid was the dominating fatty acid followed by palmitic and linoleic acids. High amounts of sterols were found in the oil with the main component β-sitosterol. Other phytosterols (e.g. stigmasterol, ∆⁷-avenasterol and ∆⁵-avenasterol) were present at approximately equal amounts (6–9 % of total sterols). The main identified hydrocarbon compounds were C₂₁, C₂₆ and C₃₂ constituting about 61.2 % of total hydrocarbons. Small amounts of C₁₂, C₁₈ and C₂₂, however, were also detected. Tocopherol levels were high in the oil (3.36 g/kg oil), wherein β-tocopherol was the main component followed by α-isomer. Both tocopherol components comprised more than 87 % of total vitamin E content in the oil. Furthermore, γ- and δ-tocopherols were detected in small amounts in the oil accounting for 14–16 % of the total vitamin E content. Information provided by the present work will be of importance for food applications and chemotaxonomy of Cistanche phelypaea.     

Enzymatic extraction of oil from yellowfin tuna (Thunnus albacares) by‐products: a comparison with other extraction methods

This study evaluated the quality of oil extracted from yellowfin tuna (Thunnus albacares) by enzymatic hydrolysis (EHO) compared with oil extracted by traditional methods, such as the physical method of cooking and pressing after fishmeal production and the chemical solvent method. The oil extracted by EHO presented the lowest acidity (1.96% oleic acid) and peroxide indexes (5.14 mEq O₂ kg^?1 of oil) and the highest levels of eicosapentaenoic acid (6.05g 100 g^?1) and docosahexaenoic acid (27.15 g 100 g^?1), two omega‐3 fatty acids with high nutritional value. Importantly, oil extraction from yellowfin tuna heads using EHO produced oil rich in omega‐3s with no oxidation. This study shows that this extraction method greatly increases the value of fish by‐products and increases the competitiveness of the fishing industry.     

Complexes of Starch and its Related Materials with Organic Compounds. Part. X. X-Ray Diffraction of Amylose-Fatty Acid Complexes

X-ray diffraction analyses of the complexes of amylose with a wide variety of fatty acids were carried out. The unit cell dimensions of the complexes were calculated for both the wet and dry states. Both the 6₁- and 7₁-helical conformations of amylose were found in these complexes, and the conformation seems to depend on the linear chain length of the acid molecules. The orthorhombic unit cell was proposed for the 7₁-helical structure of the wet complexes. The dibasic acid gave the crystal modification of the complexes exhibiting the diffraction pattern of hexagonal or orthorhombic nature. It was also found that complexations with n-propionic acid give rise to three kinds of the patterns, depending on the amount of n-propionic acid added to aqueous solution of amylose.     

Optimization of cyclopropane fatty acids production in Yarrowia lipolytica

Cyclopropane fatty acids, which can be simply converted to methylated fatty acids, are good unusual fatty acid candidates for long-term resistance to oxidization and low-temperature fluidity useful for oleochemistry and biofuels. Cyclopropane fatty acids are present in low amounts in plants or bacteria. In order to develop a process for large-scale biolipid production, we expressed 10 cyclopropane fatty acid synthases from various organisms in the oleaginous yeast Yarrowia lipolytica, a model yeast for lipid metabolism and naturally capable of producing large amounts of lipids. The Escherichia coli cyclopropane fatty acid synthase expression in Y. lipolytica allows the production of two classes of cyclopropane fatty acids, a C17:0 cyclopropanated form and a C19:0 cyclopropanated form, whereas others produce only the C17:0 form. Expression optimization and fed-batch fermentation set-up enable us to reach a specific productivity of 0.032 g·L⁻¹·hr⁻¹ with a genetically modified strain containing cyclopropane fatty acid up to 45% of the total lipid content corresponding to a titre of 2.3 ± 0.2 g/L and a yield of 56.2 ± 4.4 mg/g.     

Nondestructive estimation of fatty acid composition in soybean [Glycine max (L.) Merrill] seeds using Near-Infrared Transmittance Spectroscopy

The potential of Near-Infrared Transmittance (NIT) Spectroscopy for estimation of fatty acid composition in soybean seed samples was studied. Total 612 whole seed samples with wide range of variability for major fatty acids were used to develop calibration equations by applying SNV de-trend and first derivative mathematical treatment in the range of 850–1048 nm. Useful chemometric models for most important fatty acids present in soybean seed oil were developed using Modified Partial Least Squares (MPLS) regression method. In external validation oleic (r² = 0.89, SEP = 1.61), linoleic (r² = 0.86, SEP = 1.50) and palmitic (r² = 0.89, SEP = 0.17) acids were predicted with good accuracy, while the predictions for linolenic acid (r² = 0.78, SEP = 0.36) and stearic acid (r² = 0.63, SEP = 0.11) had relatively poor accuracy. The whole-seed NIT spectroscopy equations for fatty acid estimation would be useful for improving efficiency of breeding programs aimed at altering fatty acid composition in soybean.     

Effect of the addition of fatty acids on rice starch properties

The effect of the addition of the two fatty acids (stearic and linoleic acid) on starch pasting, thermal properties and the leaching of amylose during the gelatinization process are presented. The addition of stearic acid (C18:0) at 1.0% level (w/w, on the basis of starch) significantly changed starch pasting characteristics in peak viscosity (P < 0.05), breakdown (P < 0.001) and time to peak viscosity (P < 0.001) as measured by RVA. In contrast, the addition of linoleic acid (C18:2) showed less impact on the three RVA parameters. Thermal studies with DSC suggested that the addition of both fatty acids did not significantly influence the starch gelatinization behaviour as reflected in peak width and enthalpy but there was a decrease in peak temperature. However, the addition of the saturated fatty acid produced a significant decrease in the retrogradation endotherm (P < 0.01) compared to that of native starch. It is suggested that the saturated fatty acid complexes with amylose and is preferentially introduced into the starch granule. The double bond in the linoleic acid apparently hinders complexation. After complexation, hydrophobicity was further enhanced with the content of amylose in the hot-water soluble fraction being significantly reduced (P < 0.01) as determined by HPLC.     

Effects of Fatty Acid Addition on the Physicochemical Properties of Corn Starch

The effect of addition of six fatty acids (stearic, palmitic, myristic, oleic, palmitoleic, and myristoleic acid) on the gelatinization, glass transition, and retrogradation properties of corn starch as well as their complexing abilities with amylose were determined. Differential scanning calorimeter studies reflected that addition of fatty acids caused a 73–89% decrease in the gelatinization enthalpy compared to that of the native starch. Besides amylose-lipid formation, exotherm was determined at the same temperature range with the gelatinization endotherm. As a result, it was suggested that fatty acids complexed with amylose during gelatinization. Fatty acid addition significantly increased the glass transition temperature of starch gel. This was attributed to two reasons: the first is due to the physical cross-linking action of amylose–lipid complexes in starch-water system; the second may be due to the effect of uncomplexed fatty acids on water distribution in the gel structure as a result of their amphiphilic character. Thermal properties of amylose-lipid complexes were compared in order to determine the effect of fatty acid properties. It was found that the shorter chain length and unsaturation favored the complex formation but the complexes formed by longer and saturated fatty acids were more heat stable. Addition of fatty acids resulted in 73–90% and 47–71% reduction in the retrogradation enthalpy compared to native starch gels at 5°C and 21°C, respectively. The reduction in the retrogradation enthalpy was inversely related to the amylose-lipid complexing abilities of the fatty acids and it might be explained by the hindrance effect of uncomplexed fatty acids to the water distribution in the starch gel matrix.     

DMSO/H2O法制备高链玉米淀粉-脂肪酸包合物的热性质

采用差示扫描量热仪和热重分析仪研究脂肪酸的链长和不饱和度对高直链玉米淀粉-脂肪酸包合物热性质的影响,并利用X-射线衍射仪对其结晶结构进行了分析。研究表明,高直链玉米淀粉-脂肪酸包合物的复合指数、糊化焓值和相对结晶度均随着脂肪酸碳链长度和不饱和度的增加而减小。与高直链玉米淀粉相比,高直链玉米淀粉-脂肪酸包合物的糊化起始温度、峰值温度和终止温度随脂肪酸碳链长度的增加而升高,分别增加了23~27、26~29、27~29℃;包合物的玻璃化转变温度和最快反应速率对应的温度随不饱和度的增加而降低,下降了约0.3~1.0℃。淀粉与脂肪酸复合后晶型由B型变为V型。     

Complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures

Effects of the type and amount of fatty acid (0-2.0 mmol/g-starch of lauric, myristic, palmitic, stearic, oleic, and linoleic acids) on the complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures were investigated. Complex index (CI) evaluated by the reduction in the iodine binding capacity of starch increased with an increase in the amount of fatty acids, and reached a plateau depending on the type of fatty acid. The maximum CI value was higher in the order of lauric (49.9%), linoleic (47.6%), myristic (42.4%), oleic (36.7%), stearic (35.3%), and palmitic acid (30.9%). From the calorimetric study, it was demonstrated that melting temperature of the complexes was higher in the order of stearic (96.7 °C) > lauric, myristic, palmitic, and oleic (89.6-92.1 °C) > linoleic acid (78.3 °C). Melting enthalpy for complexes was roughly related to the CI value (R² = 0.667). From the in-vitro digestibility measurement, it was found that a certain amount of fatty acid reduced the starch content hydrolyzed at a given condition. Among them, 0.50 mmol/g-starch lauric and oleic acid samples showed the largest reduction in the hydrolyzed starch content. This result was related to the extent of complex formation characterized by CI value and its helical order characterized by melting temperature. In addition, there was a possibility of the complex formation between amylose and unsaturated fatty acid during the hydrolysis of gelatinized starch.     

Assessment of thermo‐oxidative rancidity in sunflower oil and fried potato chips stabilised with oleoresin sage (Salvia officinalis L.) and ascorbyl palmitate by altered triglycerides and electronic nose

Oleoresin sage (Salvia officinalis) (SAG) (200–1500 mg kg^?1), ascorbyl palmitate (AP) (100–300 mg kg^?1) and TBHQ (200 mg kg^?1) were assessed for delaying the thermo‐oxidation in sunflower oil (SO) during 18 h of frying (180 °C). Electronic nose compared the global aroma fingerprints of potato chips fried in oils. The chemical rancidity indices viz., fatty acids, total polar compounds (TPC), altered triglycerides (dimers, polymers, oxidised monomers, diglycerides), free fatty acids, conjugated dienes and induction periods were monitored along with physical indices viz., viscosity and colour. SO_SAG+AP (1309.62 + 270.71 mg kg^?1) outperformed SO_TBHQ by preserving polyunsaturated fatty acids (60.48% vs. 56.23%), retarding TPCs (28.16% vs. 29.91%), triglyceride dimers (90.24 vs. 95.82 mg g^?1) and polymers (25.40 vs. 26.98 mg g^?1) concomitantly extending the oil disposal time (basis 25% TPC) (15.9 vs. 14.7 h). The postfrying viscosity, colour values and global aroma fingerprints of fried chips indicate a close match between SO_SAG+AP and SO_TBHQ.     

Green recovery of phenolic compounds from rice byproduct (rice bran) using glycerol based on viscosity,conductivity and density

Rice bran, the industry byproduct, contains high levels of phenolic compounds. Based on glycerol, a green recovery of phenolics from rice bran was proposed. Extraction temperature (X₁), glycerol concentration (X₂) and liquid-to-solid ratio (X₃) were optimised by response surface methodology. Basic physical properties, that is, viscosity, conductivity, density were analysed and UPLC-Triple-TOF/MS method was applied for phenolic identification. Results showed the optimum conditions were X₁ = 66.76 °C, X₂ = 19.47% and X₃ = 32.92 mL g⁻¹. Under these conditions, the recovery yield in total polyphenols was 708.58 ± 12.36 mg GAE/100 g DW. Moreover, the recovery capacity of phenolic compounds was significantly correlated with viscosity, conductivity and density of glycerol solution. Under the optimal conditions, totals of thirteen phenolic compounds were identified and phenolic acids (4-hydroxybenzoic acid, vanillic acid, syringic acid, 4-coumaric acid, ferulic acid and salicylic acid) were quantified. These results demonstrate glycerol can serve as an ideal green solvent to recover phenolic compounds from rice bran.     

Effects of fatty acid chain length on properties of potato starch–fatty acid complexes under partially gelatinization

A series of starch–fatty acid samples were prepared using potato starch and four fatty acids differing in their chain length, including lauric (C12), myristic (C14), palmitic (C16), and stearic (C18) acids. The results indicated that the fatty-acid chain length played a significant role in altering the properties of potato starch–fatty acid complexes. The complexing index of potato starch–fatty acid complexes decreased from 0.38 to 0.18 with increasing carbon-chain length. V-type crystalline polymorphs were formed between starch and four fatty acids, with shorter chain fatty acids preserving more crystalline structure. X-ray diffraction studies revealed that the degree of crystallinity exhibited by the starch samples was dependent on the fatty-acid chain length. In the Fourier transformed infrared spectrum of the samples, the new spikes at 2917, 2850, 1018, and 720 cm^?1 were assumed to be related to the presence of fatty long chains. The formation of amylose–fatty acid complex inhibited granule swelling of potato starch, w\ith longer chain fatty acids showing greater inhibition. Scanning electron microscopy microscopic examination indicated that amylose–fatty acid interactions taken place during starch gelatinization retarded the destruction of the granules.