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Tigernut has been recognized as a promising resource for edible oil and starch. However, the research on the quality characteristics of tigernut from different regions is lagging behind, which limits the application of tigernut in food industry. Tigernut tubers were obtained from six major growing regions in China, and the physicochemical properties of their main components, oil and starch, were characterized. Tigernut tubers from Baoshan contained the most oil (30.12%), which contained the most ß-carotene (130.4 µg/100 g oil) due to high average annual temperature. Gas chromatography analysis and fingerprint analysis results indicated that tigernut oil (TNO) consists of seven fatty acids, of which oleic acid is the major component. Changchun TNO contained the least total tocopherols (6.04 mg/100 g oil) due to low average annual temperature. Tigernut tubers from Chifeng (CF) contained the most starch (34.85%) due to the large diurnal temperature range. Xingtai starch contained the most amylose (28.4%). Shijiazhuang starch showed the highest crystallinity (19.5%). Anyang starch had the highest pasting temperature (76.0°C). CF starch demonstrated superior freeze-thaw stability (syneresis: 50%) due to low mean annual precipitation. The results could be further applied to support tigernut industries and relevant researchers that looks for geographical origin discrimination and improvements on tigernut quality, with unique physicochemical and technological properties. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, subcritical n-butane was adopted to extract oil from flaxseed. The extraction conditions i.e. extraction temperature, extraction time, and liquid-solid ratio were investigated and optimized by response surface methodology. The flaxseed oil obtained by subcritical n-butane were characterized and compared with those prepared by n-hexane and cold pressing. Results indicated that the optimal combination of parameters was 53.93°C, 56.82 min, and 19.98:1 mL/g. Subcritical n-butane had higher yield (28.75%) than n-hexane and cold pressing. GC analysis indicated that subcritical n-butane extraction had no obvious influence on the fatty acid composition. Nevertheless, the oil obtained by subcritical n-butane with higher contents of phytosterols (2.93 mg/g) and carotenoids (46.56 mg/kg), and presented a higher oxidation stability (9.27 h). Thus, it was suggested that subcritical n-butane extraction is a promising alternative to extract high quality flaxseed oil. [ABSTRACT FROM AUTHOR]

Although cold-pressed sesame oil (CPSO) possesses high nutritional value, its application in the food industry is limited due to its poor oxidative stability. The aim of this study was to enhance the oxidative stability of CPSO by complex coacervation microcapsule technology with gelatin and gum Arabic as wall materials. The characterization of CPSO microcapsules were evaluated by a particle image analyzer, a laser particle size distribution analyzer, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The encapsulation efficiency (EE) reached 90.25%. The average particle size of the microcapsules was approximately 117.1 µm and many oil droplets were encapsulated by complex coacervation to form a multinuclear spherical microcapsule. The FTIR study confirmed that the process of complex coacervation was formed between gelatin and gum Arabic by electrostatic interactions. The TGA study suggested that the microcapsules had good heat resistance. The fatty acid composition, the content of sesamin, sesamolin and vitamin E in CPSO were determined before and after microencapsulation. It showed that the microencapsulation process had almost no effect on the fatty acid composition, sesamin and sesamolin, only Vitamin E was slightly lost during the microencapsulation process. The accelerated storage test showed that microencapsulation significantly increased the oxidative stability of CPSO. [ABSTRACT FROM AUTHOR]

This investigation was carried out to offer insight into the formation and antioxidant activity of Maillard reaction products (MRPs) derived from various sugar-amino acid model systems active in the roasting of sesame seeds. Reducing sugars (glucose, fructose, and xylose) and amino acids (serine, cystine, arginine, and lysine) present in sesame seeds were used to prepare the MRPs at various reaction times, and then the effect of reaction time on the MRPs derived from the various model systems was investigated. Within the first 15 min, the amounts of free amino groups decreased around 40% remaining amino groups of Lys-sugar model and around 75% remaining amino groups of Arg-sugar model. Results indicated that reducing sugar and free amino groups decreased obviously in Lys- and Arg-model systems. Based on correlation coefficient of antioxidant activities assessment and MRP formation in the Lys- and Arg-model systems above 0.978 and an extremely significant correlation in Pearson test exists, a conclusion could be made that these model systems are critical contributing factors in MRP formation during the roasting of sesame seeds. These findings offer insight into the formation and antioxidation of MRPs during the sesame seeds roasting. [ABSTRACT FROM AUTHOR]

The effects of extraction conditions on the yield of polysaccharides from the fruit of Chaenomeles sinensis (FCS) using a hot compressed water method were investigated. The results showed that an appropriately high temperature (150 °C) and a moderate extraction time (45 min) at a material to water ratio of 1 to 10 g/mL led to a high yield of alcohol precipitation polysaccharide (PA). The purified polysaccharides (CSP-1, CSP-2, and CSP-3) were successfully obtained using a DEAE-52 chromatographic column. Chemical analysis showed that CSP-2 and CSP-3 were homogenous and exhibited characteristics of esterified pectins, whereas CSP-2 mainly consisted of galacturonic acid (GalA), galactose (Gal), arabinose (Ara), rhamnose (Rha), and mannose (Man) with an average molecular weight of 59.1 kDa. Furthermore, CSP-1 possessed stronger antioxidant ability according to DPPH scavenging and reducing power compared with CSP-2 and CSP-3. However, it was weaker with respect to OH scavenging. The technical data presented in this study could help the industry make use of polysaccharides from FCS as a source of pectin for a range of pharmaceutical, culinary, and cosmetic products. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to elucidate the structural changes of the polysaccharides isolated by hydrothermal treatment of corn bran after twin-screw extrusion. The structures and antioxidant activities of the purified polysaccharides were investigated and compared by monosaccharide analysis, Fourier transform infrared (FT-IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR). The results showed that the structures of the linkages and monosaccharide components of the purified polysaccharides were not affected strongly by the twin-screw extrusion pretreatment. However, the purified polysaccharides isolated from pretreated samples displayed significant differences in monosaccharide ratios, degree of branching/linearity, and molecular weight. These physical changes may be related to the decrease of antioxidant activities of the polysaccharides. The present investigation contributes to the knowledge of how pretreatment by twinscrew extrusion affects the chemistry of corn bran polysaccharides. Results can be applied to improve the efficiency of hydrothermal extraction of polysaccharides from corn bran. [ABSTRACT FROM AUTHOR]

The chemical characteristics, rheological properties and sensory evaluation of nine different brands of the sesame pastes were investigated. The sesame pastes showed a significant difference for the crude fat, protein, crude fibre, total sugars, total ash, moisture content, and acid values (p < 0.05). The fat content ranged from 51.80% to 61.56%, and the protein content varied between 16.08% and 18.97%. All sesame paste samples are pseudoplastic materials. The flow indexes lied between 0.67 and 0.81 for the tested sesame pastes (p > 0.05). The consistency coefficient of the different sesame paste brands varied significantly (p < 0.05), ranging from 4.48 to 24.21 Pa・sn, indicating that the consistency coefficient is a more sensitive parameter for measuring the flow behaviour of foodstuff. The areas of the hysteresis loops of the whitesesame paste of "Haoweisi" brand and the black-sesame paste of "A Yimeng couple" brand were higher than the other sesame pastes, indicating that these two samples were difficult to be restored to their original structures and such restoration required a longer time. Both Storage modulus (G') and loss modulus (G") of the sesame pastes increased with increasing frequency, and G' values were greater than the G" values, exhibiting the typical properties of the viscoelastic solid, the results may provide the valuable reference for choosing the sesame pastes as the spreadable butters or salad dressings, and for further processing. [ABSTRACT FROM AUTHOR]

Chinese quince seed (CQS) is an underutilized oil source and a potential source of unsaturated fatty acids and α-tocopherol-rich oil. Subcritical fluid (SCF) extraction is executed at lower pressures and temperatures than the pressures and temperatures used in supercritical fluid extraction. However, no studies on the SCF extraction of CQS oil are reported. Therefore, the objective of this study was to evaluate the use of SCF for the extraction of CQS oil and to compare the use of SCF with the classical Soxhlet (CS) and supercritical CO2 (SC-CO2) extraction methods. Response surface methodology (RSM) was used to investigate the extraction conditions: temperature (45-65 °C), time (30-50 min), and solvent/solid ratio (5-15 mL/g). The optimization results showed that the highest yield (27.78%) was obtained at 56.18 °C, 40.20 min, and 12.57 mL/g. The oil extracted by SCF had a higher unsaturated fatty acid content (86.37%-86.75%), higher α-tocopherol content (576.0-847.6 mg/kg), lower acid value (3.97 mg/g), and lower peroxide value (0.02 meq O2/kg) than extractions using CS and SC-CO2 methods. The SCF-defatted meal of oilseed exhibited the highest nitrogen solubility index (49.64%) and protein dispersibility index (50.80%), demonstrating that SCF extraction was a promising and efficient technique as an alternative to CS and SC-CO2 methods, as very mild operating conditions and an eco-friendly solvent can be used in the process with maximum preservation of the quality of the meal. [ABSTRACT FROM AUTHOR]

Rice bran oil was extracted using hexane, as well as subcritical butane and propane. The quality of rice bran oils obtained using these three solvents was comparatively studied. The results showed that subcritical fluid extraction oil showed higher concentrations of health-conducive components (such as vitamin E, oryzanol, and phytosterol) compared with hexane-extracted oil. Extraction solvent had an important effect on the distribution of linoleic acid and oleic acid. The sterol compositions in rice bran oils were identified to be composed of ethyl iso-allocholate, campesterol, stigmasterol, sitosterols, and cyclolanosts. NMR data showed that butane-extracted oil had the highest triacylglycerols (TAGs) content and that subcritical propane-extracted oil had the highest wax content among the oils extracted with these three extraction solvents. The oils extracted by subcritical butane and propane showed higher oxidative stabilities. These results indicate that subcritical fluid extraction technology could be a useful method for producing high-quality rice bran oils and could become widely used in industrial applications. [ABSTRACT FROM AUTHOR]

Leaf shape is an important factor affecting canopy structure, photosynthetic characteristics, and yield. Introducing okra leaf shape is considered an important strategy in cotton heterosis breeding. The objective of the study was to evaluate the heterosis in okra leaf cotton hybrid F1s, which were developed by crossing two sterile near isolines and three restorer near isolines. A normal leaf check hybrid F1, Zhongza 29, and four newly developed okra leaf oriented hybrid F1s, including the super-okra (severely cleft and narrowly lobed leaf), okra (deeply cleft and narrowly lobed leaf), semi-okra (intermediate leaf lobe), and sub-okra (large leaf lobe) hybrids were selected in this experiment. Okra leaf oriented cotton hybrids significantly reduced leaf area index (LAI) ( P < 0.0001), thus more light penetrated into the lower canopy. The LAIs for the super-okra and okra hybrids, however, were too small to supply adequate photosynthate, thus resulting in early maturity, short boll filling period, and low yield. As the LAI increases, the semi-okra and sub-okra hybrids showed certain heterosis. The semi-okra hybrid showed 7–12% heterosis over the check hybrid in lint percent, 6–11% in boll weight, 2–147% in canopy light intensity, 1–10% in net photosynthetic rate (Pn), and −3 to 3% in lint yield. As well, all tested okra leaf hybrids improved fiber quality such as micronaire compared with the normal leaf check hybrid. The results suggested that adopting okra leaf parental lines in cotton breeding provided potentials in increasing fiber quality with comparable lint yield. [ABSTRACT FROM AUTHOR]

A fiberless seed mutant (fl) was identified in a commercial cotton ( Gossypium hirsutum L.) variety Xu-Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl-E6 and FL-E6, were cloned from fl-integument cells and FL-fiber or integument cells, respectively. Compared with FL-E6, fl-E6 showed a dramatic change in nucleotide sequence: (1) FL-E6 contained a tandem repetitive sequence in which GGCTCA (Gly-Ser) is repeated five times between the 82nd and the 93rd codon from the first ATG codon, while in fl-E6 the same sequence is repeated four times; (2) The fl-E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and three between the 171st and 174th relative to FL-E6; (3) There are also 12 nucleotide substitutions which would result in 7 amino acid differences between fl-E6 and FL-E6. Analysis of RT-PCR and Northerm Blot showed that expression of the fl-E6 gene is suppressed in the fl-integument cells, but highly expressed in FL-fiber cells. The difference between fl-E6 and FL-E6 may be associated with lower expression of fl-E6 in the fl-integument cells. Searches of protein databases with the FL-E6 gene sequence showed similarity to the protein backbones of two arabinogalactan-proteins (AGPs), one from the filtrate of suspension-cultured cells of Pyrus cornmunis (AGPPc2) and the other from Nicotiana alata (AGPNa2). Although the function of the FL-E6 protein in differentiation and development of cotton fiber cells is not known, the data indicate that the mutation of fl-E6 gene from FL-E6 gene may inhibit the fiber cell initiation from epidermal cells of the outer integument of the ovule. [ABSTRACT FROM AUTHOR]