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The conversion of sesamin to asarinin is a promising route for the production of asarinin. This work reports the affection of acid type and strength of the catalyst on the conversion of sesamin to asarinin and the effect of various reaction conditions in anhydrous ethanol using phosphotungstic acid (HPW) as catalyst. The experimental results indicate that the activity of sesamin conversion is determined by strong B acids. L acids are not active for the reaction, and do not show synergy with B acids for the formation of asarinin. Reaction time, HPW dosage and temperature have significant effects on sesamin conversion. A maximum asarinin yield of 57.93% was achieved. The reaction kinetics in the temperature range 55-75 °C were studied. The kinetic curves can be successfully fitted with an opposing first-order reaction model. The activation energy (Ea) for this reaction is found to be 105.2 ± 0.4 kJ/mol.

Sesame oil is one of the most commonly used oils in life. It contains a special antioxidant substance called sesame lignans, which has high nutritional value and pharmacological activity. Chromatographic methods are accurate and reliable but not suitable for quality control due to time-consuming. Near-infrared (NIR) quantitative models for quickly determining sesamin, sesamolin and sesame lignans in sesame oil were built using a portable NIR spectrometer combined partial least squares(PLS) algorithm, and the optimal PLS models were developed by comparing the performance of the models with different spectral pretreatment methods and bands selection, the correlation coefficients (R2) were RC2 = 0.98, 0.99, 0.99, RP2 = 0.99, 0.97, 0.94, and the root mean square error (RMSEP) was 2.69 μg/mL, 3.73 μg/mL, and 7.96 μg/mL, respectively. The acceptable results demonstrated that portable NIR spectrometer could be used for monitoring the contents of sesamin, sesamolin, and sesame lignans in sesame oil during the production process to carry out quality control.

This study investigated the changes in aroma composition and perception of sunflower oils induced by seed roasting using sensory-oriented flavor analysis. Volatile compounds were extracted by solvent-assisted flavor evaporation and headspace solid-phase microextraction. Odorants were characterized by gas chromatography-olfactometry-mass spectrometry and aroma extract dilution analysis. The cold-pressed and roasted sunflower oils contained 13 and 50 odorants, respectively, with the flavor dilution factors between 1 and 256. Fifty-six odorants were newly identified in sunflower oils. Quantification of 26 important odorants by the external standard method revealed apparent changes induced by seed roasting in loss of terpenes, formation of Maillard reaction products, and the increase in lipid oxidation products. The most important odorants (odor active values, OAVs = 1-1857) in the cold-pressed sunflower oil included α-pinene (11,145 µg/kg), β-pinene (4068 µg/kg), linalool (56 µg/kg), hexanal (541 µg/kg), octanal (125 µg/kg), α-phellandrene (36 µg/kg), and (E)-2-octenal (69 µg/kg), contributing to the raw sunflower seed, woody, green, earthy, and sweet aromas of the oil. The most important contributors (OAVs = 1-884) to the roasted, smoky, and burnt aromas of the roasted sunflower oil were 2- and 3-methylbutanal (6726 and 714 µg/kg), 2,6-dimethylpyrazine (2329 µg/kg), 2,5-dimethylpyrazine (12,228 µg/kg), 2,3-dimethylpyrazine (238 µg/kg), 2,3-pentanedione (1456 µg/kg), 2-pentylfuran (1332 µg/kg), 2,3-dimethyl-5-ethylpyrazine (213 µg/kg), and 1-pentanol (693 µg/kg). Aroma recombination of the key odorants in odorless sunflower oil adequately mimicked the general aroma profiles of sunflower oils. This study provides an important foundation for understanding the relationship between oil processing and aroma molecules of sunflower oils. PRACTICAL APPLICATION: The clear changes observed in the composition and concentrations of key aroma compounds explained the changes in sensory characteristics of sunflower seed oils induced by seed roasting on a molecular basis. Characterizing the key aroma-active composition of sunflower oil and investigating its relationship with oil processing could provide important practical applications for the sunflower oil industry in flavor regulation, quality control, product development, and process optimization.

The objective of the present investigation was to extract pectic polysaccharides from sesame seed hull and to determine their physicochemical and functional characteristics. The pectic polysaccharides in the seed hull were extracted with HCl and then collected at three ethanol concentrations of 30% (SSP30), 50% (SSP50), and 90% (SSP90). We found that SSP30 represented 75.6% of the total polysaccharides, and that it contained 76.39% galacturonic acid, with many HG domains and few short side chains in the RG-I domains. SSP30 exhibited the strongest hydroxyl radical scavenging activity among the three fractions, and was better able to stabilize the emulsions. Higher Mw pectic polysaccharides were firstly precipitated at lower ethanol concentrations, and the Mw of the precipitated pectic polysaccharides decreased with increasing ethanol concentration. These results provide important information on the structure and functional characteristics of sesame hull polysaccharides. This information can contribute to the future development of sesame hull polysaccharides for industrial purposes.

Edible oil is prone to be contaminated by Benzo[a]pyrene (BaP) during production and processing. Adsorption is an important technology for the removal of BaP from edible oil, and biochar as a new type of adsorbent for the treatment BaP has received extensive attention. In this study, we prepared unmodified biochar and ZnCl2-modified biochar from sesame straw cellulose (SSB and SSZ) and sesame capsule cellulose (SCB and SCZ), carried out structure characterization by Fourier Transform Infrared (FT-IR), Brunauer-Emmett-Teller (BET) and Scanning Electron Microscope (SEM), and finally evaluated their potential effectiveness in BaP removal from sesame oil. FT-IR results revealed that SSZ and SCZ showed higher peak intensities, indicating that they could provide more active sites for adsorption. The results of XRD presented that SSZ and SCZ had a higher graphitization degree than the unmodified biochar. SEM results showed that the SSZ and SCZ had more complex pore structure, which is beneficial to adsorption. BET analysis results showed that SSZ and SCZ have a higher specific surface area of 1622.83–1797.39 m2/g and a better developed porous structure (the total pore volume Vtotal is 0.9434–1.0023 cm3/g) than the SSB and SCB (specific surface area is 350.55–352.59 m2/g, and Vtotal is 0.1907–0.1918 cm3/g), indicating that modification promotes the formation of porous structure and thus improves the adsorption capacity of biochar. Adsorption experiments confirmed once again that the BaP removal rates (92.67%–96.13%) of SSZ and SCZ were much higher than that of unmodified biochar (3.34%–4.28%), and the BaP content in the sesame oil treated by SSZ and SCZ were far below the current EU maximum levels (2 μg/kg). Therefore, the modified biochar from cellulose is a promising adsorbent for BaP removal. In future studies, the influences of bichar on the nutritional quality of edible oil should be taken into consideration so as to find an ideal active carbon substitute for BaP removal in edible oil.

Chinese quince (Chaenomeles sinensis) fruits offer a potential source of pectin and hemicellulose. However, the existence of lignin-carbohydrate complexes (LCCs) can negatively impact the extraction of pectin and hemicellulose. In this work, LCCs were sequentially fractionated from Chinese quince during the removal of pectin and hemicellulose. The structures of LCCs were characterized by HPAEC, FT-IR, GPC, Py-GC/MS, TGA and 2D HSQC NMR. The results showed that the carbohydrate content and molecular weight of LCCs was found to be changed significantly after the removal of hemicellulose (KSH). The lignin in Björkman LCCs was found to be linked mainly to galactan and fructan, whereas the lignin LCC-AcOHs was found to be linked mainly to arabinan after the removal of KSH. The isolation of carbonate-soluble pectin (NSP) increased thermal stability of Björkman LCC fraction, however, the isolation of chelator-soluble pectin (CSP) increased the thermal stability of LCC-AcOHs. The S/G ratios of LCC-AcOHs increased and large amounts of S-type lignin released during sequential fractionation of pectin and hemicellulose. These results will be beneficial for understanding the mechanisms of pectin and hemicellulose isolation, thereby facilitating the potential application of Chinese quince as a valuable natural resource for food and other industries.

Corn is a high starchy cereal crop with the highest production and provides over 85% of the starch produced worldwide. Various by-products, differentiated by technological process features such as steep liquor, corn germ, corn bran, gluten, are created largely during corn starch processing. They are inexpensive, nutrient-rich, and vary widely in chemical composition such as proteins, oils, carbohydrates, and minerals. In an increasingly resource-constrained modern world, the utilization approach of these by-products for non-starch industrial processing is attractive widely considering both nutritive value and economic aspects. In fact, at present, applications of these by-products can often be found in feed, fermentation, nutrient extraction and other industries. For example, protein-rich corn gluten can be used as a good animal feed, and corn germ can be used as a raw material for the high-quality edible oil industry. Undoubtedly, increasing utilization means that these by-products will no longer be treated as waste but will be transformed into high value-added products. In this work, the separation process and chemical composition of several main by-products of the corn starch industry is briefly described, and the application in many industrial fields of these by-products over the last ten years are discussed in particular. This review attempts to summarize all aspects of the application and research of these by-products. For the by-products of the corn starch industry, the most promising way is to be utilized in high value and used to produce high value-added products. According to the characteristics of their chemical composition, they have a better application prospect and research significance in the industries directly related to human beings, such as medicine, green food and health care products. In fact, in recent years, some researchers have recognized this and carried out the research. It is clear from these studies that the main issues to be faced now and in the future are how to produce efficiently while maintaining the quality of the product and using it effectively. The retrospective discussions also provide some ideas for other grain and oilseed crops to be fully utilized.

The main objective of the present investigation was to evaluate the potential of using the seed gum of Chinese quince (CQSG) as a wall material for flaxseed oil microencapsulation via freeze-drying...

Chinese quince is one kind of crop that has edibility and historical medical applications. However, the high amount of lignin makes processing Chinese quince fruit difficult; on the other hand, this lignin represents a valuable resource if a way of using it in industrial applications could be found. In this study, the structural features and antioxidant activities of Brauns native lignin (BNL) isolated from Chinese quince fruit after oven drying (60 °C, 75 °C, and 90 °C), sun drying, freeze-drying, and subcritical dimethyl ether drying were assessed. The BNL samples had low molecular weights (Mw, 2604–5511 g/mol), high carbohydrate content (6.10–9.95 %), and high phenolic OH content (1.76–2.29 mmol/g). NMR spectra showed that the BNL is of the SGH-type with the relative content of p-hydroxyphenyl units ranging from 13 to 21 %. Oven drying (90 °C) reduced the carbohydrate content and increased the phenolic hydroxyl content. Freeze-drying reduced the relative content of β-O-4′ linkages and increased the H-unit content. In terms of antioxidant activities, all samples possessed high DPPH free radical scavenging capacity (IC50, 0.12−0.22 mg/mL) and strong reducing power. These results indicate that BNL extracted from Chinese quince fruit is a promising source of natural antioxidant and biomass material.

If the tigernut meal left after oil extraction is used as a material for starch resources instead of being wasted, the industrial value of tigernut would be improved. Thus, we investigated the effect of extrusion before oil extraction on the yield, structure and function of starches within tigernut meals (TMS). Compared with the yield of native starch, the yield of TMS-130-11 (barrel temperature: 130 °C; feed moisture: 11 %) was increased by 1.97 %, and that of TMS-140-11 (barrel temperature: 140 °C; feed moisture: 11 %) was decreased by 7.82 %. The starches cannot be obtained when the barrel temperature is above 140 °C with 11 % feed moisture. Extrusion slightly decreased the relative crystallinity and increased the ratio of B2-chains in amylopectin. These changes resulted in reductions in peak viscosity while improving the elastic properties of the starch gel. These results will provide useful information regarding the use of starch isolated from tigernut meal.

This article reports a study of the degradation of roasted sesame hulls cellulosic polysaccharides contribution to the Maillard and caramelization reaction. In the present study, cellulosic polysaccharides were extracted from sesame hulls before and after roasting at various temperatures (160, 180, 200, and 220 °C). The structural vari-ations of the cellulosic polysaccharides were elucidated by using the techniques: scanning electron microscope (SEM), high-performance anion-exchange chromatography, Fourier transform (FT-IR) spectrometer, carbon-13 nuclear magnetic resonance (CP/MAS 13C-NMR), and thermal gravimetric analysis. The pyrolysisgas chromatography-mass spectrometry (Py-GC/MS) characterized and verified the chemical composition obtained from the polysaccharide degradation during roasting. The sugar analysis results showed that galacturonic acid, xylose, and rhamnose were more easily degraded than arabinose, galactose, glucose, and mannose. The morphology of the cellulosic polysaccharides shows irregular dispersed globular fragments after roasting by SEM observation. FT-IR and CP/MAS 13C-NMR spectra indicated the crystalline structure and linkages of the cellulose did not break down in comparison to amorphous cellulose that partly degraded. Abundant acetic acid and 3-furaldehyde were among the polysaccharide degradation products identified by Py-GC/MS. These chemical compounds were likely the significant contributors to caramelization and the Maillard reaction in sesame seed roasting.

Chinese quince fruit is rich in proanthocyanidins (PAs), which have antioxidant properties. This work describes a method to isolate PAs from Chinese quince fruits by a combination of ball-milling pretreatment and enzyme-assisted extraction. Untreated PA fractions (UMP), ball mill pretreated PA fractions (BMP) and enzymatically hydrolysed PA fractions (BEP-1, BEP-2, BEP-3, BEP-4) were obtained. The total PA and total phenolic contents, antioxidant activity and α-amylase inhibitory activity of the six PA samples were determined, and their structural characteristics were also analyzed. BEP and BMP fractions were structurally similar with UMP, but had more total phenolics and PAs, and had higher antioxidant activities, lower thermal stability, and lower average molecular weight. Among them, BEP-4 was the most outstanding. Its total phenolics and PAs were 750.98 ± 6.95 and 948.72 ± 3.50 mg/g extract per gram dry weight, respectively. Its DPPH, ABTS, hydroxyl radical scavenging ability, and α-amylase inhibitory capacity had maximum values of 90.38%, 98.99%, 97.89%, and 92.98%, respectively. These investigations provide a new, efficient way to isolate proanthocyanidins from Chinese quince fruits, and reveal that Chinese quince fruits may be a good source of antioxidants, worthy of further development.

Sesame cake and meal, byproducts of the sesame oil process industry and mainly used as feed and fertilizer, are often not optimally utilized and are wasted when the material could be used as a high-quality protein source. This research primarily emphasizes the preparation of a sesame protein-based adhesive with urea and glyoxal modification to use as a wood adhesive. The performance and characterization of the urea and glyoxal modified sesame protein adhesive (USP and GUSP, respectively) were measured precisely. After glyoxal was added, the water resistance of the GUSP adhesive was significantly enhanced, reaching the standard for Type II plywood. The formaldehyde emission test showed that the GUSP adhesive could be utilized as a formaldehyde-free wood adhesive, having a significantly lower than the demand of the E0 level (i.e., 0.5 mg/L). Furthermore, increasing the glyoxal content in the adhesives enhanced the thermal stability but not significantly. A substance with a crosslinking structure was formed from the reaction between the sesame protein and glyoxal, which enhanced the water resistance. Meanwhile, the fractured structure of the GUSP adhesive having a compact surface also was propitious to enhance the water resistance. Thus, the GUSP adhesive could be used as a novel adhesive in plywood fabrication.

Lignin from the Chinese quince (Chaenomeles sinensis) fruit offers a promising source of natural antioxidant for industrial applications. However, the utilization of Chinese quince fruit lignin is restricted by its inhomogeneous nature. Accordingly, Chinese quince fruit lignin was sequentially fractionated with organic solvents of increasing dissolving capacity to prepare homogeneous lignin fractions. The GPC (gel permeation chromatography) results showed that the molecular weights of lignin fractions increased from dichloromethane fraction to dioxane/water fraction. The five lignin fractions were also compared with respect to yield, carbohydrate content, thermal stability, inter-unit linkages, S/G ratios, and phenolic OH content. Among the five fractions, the ethyl acetate fraction showed a lower proportion of β-O-4′ linkages (48.4%), the highest thermal stability, the highest phenolic OH content (2.8 mmol/g), and the highest DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging index and reducing power. The high antioxidant performance of the ethyl acetate fraction implies that it can be used as a natural antioxidant. This study shows that sequential solvent fractionation of lignin can produce homogeneous fractions with enhanced antioxidant performance. In addition, it demonstrates that Chinese quince fruits are a potentially valuable natural resource.

Acetic acid at atmospheric pressure is an alternative solvent that can be used for high-efficiency separation of lignin. However, few studies reported the isolation of lignin using acetic acid at above atmospheric pressure. In this study, acetic acid solution at above atmospheric pressure was used to extract lignin from Chinese quince fruit. The influences of different extraction conditions on the lignin yields were firstly investigated. Among the five extraction parameters (extraction temperature/pressure, acetic acid concentration, extraction time, catalyst dosage, and solid/liquid ratio), catalyst dosage had the most important influence on lignin yields. Five acetic acid lignin (AAL80, AAL100, AAL120, AAL140, and AAL160) samples obtained at different extraction temperatures/pressures (80 °C–160 °C/0.03–0.35 MPa) were used to analyze the influence of extraction temperatures/pressures on their structural features. Comparing to lignins extracted with acetic acid at atmospheric pressure, lignins obtained by acetic acid extraction at above atmospheric pressures (AAL120, AAL140, and AAL160) had higher purity. The acetic acid could degrade lignin at temperatures above 120 °C. When extracted at 120 °C–160 °C, the depolymerization degree of lignins increased with rising temperatures. AAL160 with more condensed structures was the most thermally stable. As the extraction temperature rose, the proportion of β–5 linkages in lignins gradually increased, while the proportion of β–O–4 and β–β linkages decreased. AAL80 had the highest DPPH, while AAL120 showed the highest ferric reducing activity. The study clarifies the lignins isolated with acetic acid at above atmospheric pressure from Chinese quince fruits and contributes to their potential application.

Adinandra nitida leaf extract (ANE) is rich in phenols and flavonoids. In this study, the effects of ANE as an additive on the formation of major heterocyclic amines (HCAs), namely, PhIP, norharman and harman, in both chemical model systems and fried chicken patties were explored. In model systems, treatment with various amounts of ANE (0, 15, 30, 45, 60 mg) led to the most effective inhibition of PhIP, norharman and harman, with levels reduced by 47.88%, 49.73% and 29.63% when treated with 45 mg, 60 mg and 60 mg, respectively. Further, the effect of diverse dosages of ANE (0, 0.2, 0.4, 0.6%, w/w) on the formation of HCAs in chicken patties fried at 170 °C and 190 °C was evaluated. Statistics showed that the temperature significantly increased the formation of HCAs. Total HCA contents of patties fried at 170 °C and 190 °C ranged from 1.52 ng g−1 to 2.52 ng g−1 and from 6.05 ng g−1 to 13.76 ng g−1, respectively. The inhibitory efficacy of various concentrations of ANE on the total HCA content was higher (38.95–56.03%) in patties fried at 190 °C than at 170 °C (18.65–40.08%). External parts of the meat patties showed higher HCA contents than the interior. The current study presents evidence that ANE at moderate dosages can reduce the formation of HCAs in fried chicken. By extension it suggests that ANE has potential applications as a natural antioxidant for preventing the formation of HCAs in foods.

The spiced beef is exposed to the invading of spoilage bacteria including Listeria monocytogenes. In the present study, the antimicrobial effects against L. monocytogenes of the chitosan (CS) films incorporated with apricot (Prunus armeniaca) kernel essential oil (AKEO) at 0.5% and 1.0% were demonstrated in solid medium, micro-atmosphere, liquid media and spiced beef. In the refrigerated storage for 24 days at 4 °C, compared with the control sample, the levels of peroxide value (PV) and thiobarbituric acid (TBA) of the spiced beef packed by CS films incorporated AKEO at 0.5% and 1.0% were decreased to 4.8 and 3.6 meq peroxide/kg, and 0.5 and 0.4 mg MDA/kg (p 0.5 or p 0.1), and the levels for pH and total carbonyls (TC) were decreased to 5.8 and 5.7, and 0.7 and 0.6 nmol/mg protein (p 0.5 or p 0.1) on the 24th day, respectively. Furthermore, the sensory evaluation exhibited that the spiced beef packed by CS films incorporated AKEO at 1.0% had better sensory attributes including taste, color, texture and overall acceptance during the whole storage period. Consequently, CS films incorporated AKEO at 1.0% can be developed to be one packaging material for spiced beef.

In this investigation, the hemicellulose fractions were isolated from sesame hulls before and after roasting at 160 °C, 180 °C, 200 °C, and 220 °C. The structural properties of the hemicelluloses were comparatively investigated by analytical techniques including FT-IR, sugar compositions analysis, molecular weight analysis, thermal analysis, and NMR. Roasting at temperatures from 180 to 220 °C resulted in higher yields of hemicelluloses subsequently isolated from sesame hulls by the alkaline method. The results of sugar analysis and average molecular weight analysis of the hull hemicelluloses revealed that the side chain sugar units such as arabinose and rhamnose of the hemicelluloses are more easily degraded after roasting during the roasting. That the main chains of hemicelluloses in the cell wall of sesame seed hulls did not change significantly. The investigation provides new information about the mechanisms of the structural changes that occur in sesame hull hemicelluloses during roasting.

Chinese quince fruits are rich in proanthocyanidins (PAs), which have antioxidant properties. This work describes a method to isolate PAs from Chinese quince fruits by a combination of ball-milling and enzyme hydrolysis pretreatments. The yield, total PA and total phenolic contents, structural characteristics, antioxidant activity, and α-amylase inhibitory activity of different pretreated PA samples were determined and analyzed. Among them, the ball-milling combined with multi-enzyme (cellulase, xylanase, and pectinase) hydrolysis pretreated sample (BEP-4) was the most outstanding. The yield of BEP-4 could be improved up to 7.72%, which was 2.51 times higher than that of the conventional organic solvent extraction method (3.02%). It had the highest total phenols and PAs content of 750.98 ± 6.95 and 948.72 ± 3.50 mg/g extract, respectively. The thermal stability and molecular weight (9610 Da) of BEP-4 were lower than other fractions. BEP-4 contained a high proportion of PC structure (98.35%) and flavan-3-ol content (87.88%). It also had the highest antioxidant capacity with IC50 values of 131.45 ± 0.97, 22.66 ± 0.32, 134.05 ± 0.71, and 182.07 ± 0.28 μg/mL for DPPH, ABTS, hydroxyl radical scavenging capacity, and α-amylase inhibiting capacity, respectively. These investigations provide a new, efficient way to isolate PAs from Chinese quince fruits, and reveal that Chinese quince fruits may be a good source of antioxidants, worthy of further development.