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Summary: This study analysed the impact of adding different amounts (5–25%) of defatted tigernut flour (DTF) to frozen wheat dough at different freezing periods. The chemical composition and freeze–thaw stability of the composite flour, as well as the physicochemical properties (e.g., textural, tensile, and rheological properties) of the dough after being frozen, were assessed. It was found that the addition of DTF enhanced the nutritional value of the dough and improved quality characteristics such as texture and tensile properties of the dough after it had been frozen and thawed. With increasing DTF, the content of dietary fibre (8.69–9.63%) and ash (0.54–1.05%) increased significantly, but the content of starch (58.56–54.96%) and protein (11.03–10.35%) decreased as compared to that of wheat flour alone. The thermal and freeze–thaw stability of composite flour was greatly improved with increasing amounts of DTF, and the retrogradation of the dough was delayed. DTF (5–15%) proportionately delayed deterioration of springiness and retarded hardening of the frozen dough. In addition, the extensibility of the frozen dough was significantly increased by adding 10–25% DTF. The results suggest that DTF has the potential to positively influence the quality of frozen wheat dough, while at the same time increasing the high‐value utilisation of tigernut. [ABSTRACT FROM AUTHOR]

Summary: Sesame hull is a byproduct of sesame processing and is currently treated as waste, but it could be an important source of pectic polysaccharides. To increase the value of the sesame crop, pectic polysaccharides were extracted from sesame hull using four different chelators, namely trans‐cyclohexane‐1,2‐diamine tetraacetic acid (CDTA), ethylene diamine tetraacetic acid (EDTA), sodium tripolyphosphate (STLP), and sodium hexametaphosphate (SHMP), which were named CSP, ESP, STP, and SHP, respectively. Physicochemical and functional properties were assessed. SHP mainly contained homogalacturonan (HG) linear regions but the others had more branching with rhamnogalacturonan (RG‐I) as the predominant region. CSP showed the highest molecular weight (155 kDa) with a smooth surface. The molecular weight of ESP, STP, and SHP ranged from 40 kDa to 90 kDa and presented cracked surfaces. Furthermore, CSP had the highest oil holding capacity (9.03 g oil g−1 dry matter). ESP showed Newtonian‐fluid characteristics (n = 1.06) and weaker thermal stability than others. STP had the highest viscosity and good emulsifying stability in concentrations of 1% and 2%. SHP showed excellent water holding capacity, foaming capacity, emulsifying stability, and antioxidant activity. This study provides valuable information for selecting a suitable chelator to extract desirable pectic polysaccharides from sesame hull waste. [ABSTRACT FROM AUTHOR]

Summary: To study the physicochemical properties of sesame paste produced by a novel process technology—ball milling, the effects of different ball milling times (8, 16, 24, 32, and 40 min) at 650 rpm on particle size, texture, rheological properties, volatile compounds, consumer sensory evaluation, and microstructure of sesame paste were investigated. The results showed that ball milling has no significant differences in proximate composition and colour of sesame paste, but the D90 value of particle size decreased to 32.04 μm. Compared to others, the sesame paste ball‐milled for 8 min has the highest viscosity of 277.195 g·s. The sesame paste obtained by ball milling for 32 and 40 min produced 55 and 56 volatile compounds, respectively. Regardless of male and female, sesame paste obtained by ball milling for 24, 32, and 40 min have high overall acceptability. This investigation shows that ball milling is a new technology of potentially great value in the industrial production of sesame paste, which can be used to produce high‐quality sesame paste with specific characteristics. [ABSTRACT FROM AUTHOR]

Asarinin, an isomer of sesamin, has attracted attention because it has stronger biological properties than sesamin. The research on the conversion of sesamin into asarinin is limited. In this study, solid acid catalysts were screened and applied to promote the conversion of sesamin into asarinin in sesame oil. The results showed that citric acid loaded on zeolite beta (CTAH) was the optimal catalyst for asarinin production among the prepared catalysts. Characterization showed that CTAH had the greatest pore volume, largest surface area and strongest acid content. Response surface methodology (RSM) was applied to optimize the reaction conditions for asarinin yield using CTAH. The optimal reaction conditions were as follows: temperature, 85 °C; time, 2.7 h; catalyst amount, 1.6%. The predicted and experimental values of asarinin yield were 50.79 and 51.80 mg/100 g, respectively. The peroxide value and color in sesame oil samples treated with CTAH were clearly improved. In short, CTAH is a solid acid catalyst with potential application in the industrial conversion of sesamin into asarinin and in the improvement of sesame oil. [ABSTRACT FROM AUTHOR]

BACKGROUND Red pepper seeds account for 450-500 g kg−1 of the total pepper weight and are often discarded as waste. In this study, process optimization and characterization of fragrant oil from roasted red pepper seed extracted by subcritical butane extraction were carried out. RESULTS The optimal conditions of extraction were a temperature of 74.61 °C, a time of 68.65 min and a liquid/solid ratio of 30.24:1. The oil had a refractive index (25 °C) of 1.471, a relative density of 0.900, an acid value of 1.421 mg g−1 oil, an iodine value of 127.035 g per 100 g, a saponification value of 184.060 mg KOH g−1, an unsaponifiable matter content of 12.400 g kg−1, a peroxide value of 2.465 meq. O2 kg−1 and a viscosity of 52.094 cP. The main fatty acids in the oil were linoleic acid (72.95%) followed by palmitic acid (11.43%) and oleic acid (10.00%). The oil showed desirable thermal and oxidative stability. A total of 19 volatile compounds, mostly aldehydes and alkenes, were identified from the oil. CONCLUSION The results indicated that the method is appropriate for the preparation of fragrant red pepper seed oil, and the oil is suitable for used as edible oil. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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. • Pectic polysaccharide (SSP30) was isolated from sesame seed hull at first time. • Physicochemical and functional properties of the pectin were characterized. • SSP30 fraction exhibited better able to stabilize the O/W emulsions. • SSP30 exhibited strong hydroxyl radical scavenging activity. [ABSTRACT FROM AUTHOR]

Complete utilization of tigernut tubers, including their use in oil production and use of the meal as a byproduct, is an important aspect in improving their industrial value. However, there are few studies on the use of starch isolated from tiger tuber meals and cakes remaining after oil extraction. In this investigation, starches were isolated from tigernut tubers before and after various oil extraction processes and their structural and functional properties were comparatively investigated. A typical C-type X-ray diffraction pattern was observed for all of the isolated starches. Noticeable decreases in relative crystallinity by XRD and solid state 13C NMR were observed for starches from the cakes of tigernut tubers remaining after oil extraction utilizing a mechanical expeller. The proportion of amorphous phase (PPA) in the starches isolated from meals and cakes was relatively low compared with that of starch isolated from raw tigernut tuber. The branch-chain length distribution of the starches isolated from meals and cakes exhibited a low average chain length of amylopectin. These changes reflect a disruption in the ordered structure of starch granules caused by the various oil extraction processes, which led to significant variability in their functional properties, including paste clarity, freeze-thaw characteristics, thermal transition temperatures, texture, solubility, and swelling power. This investigation provides important information for the complete utilization of tigernut tubers. Image 1 • Various starches isolated from tigernut tubers and the meals were compared. • Oil extraction methods have an important effect on isolated starches. • Oil extraction processes disrupted the ordered structure of starch granules. [ABSTRACT FROM AUTHOR]

Roasting pretreatment enhances the commercial qualities of tigernut oil. Oil extraction leaves behind meal, which is a potential source of starch. For industry to use this starch, its physicochemical characteristics of starch in meals after oil extraction with different roasting temperatures must be known, but have not been reported. In this investigation, the physicochemical properties of starches extracted from tigernut tubers before and after roasting at four different temperatures were investigated. Roasting increased the number of double helices and the ratios of A chains while decreasing crystallinity. There were differences in starch structure among samples roasted at different temperatures, which induced functional differences. The increase in A chains led to a decrease of peak viscosity, and improvement in freeze-thaw stability; the destruction of molecular interactions caused a decrease in pasting temperature; damage to the crystalline structure caused the decrease in gelatinization enthalpy and transition temperatures. As for differences in rheological properties, the interference of non-starch components and molecular interactions appear to be major factors. This study provides scientific information for the complete utilization of tigernut tubers. • Roasting damaged the crystalline structure and glycosidic linkages of starch. • Paste viscosity decreased with increased roasting temperatures. • Roasting decreased the enthalpy change of gelatinization. • Freeze-thaw stability obviously improved with increased roasting temperatures. • The starch gel is a low storage modulus (G′) and high Tan δ (G″/G′) after roasting. [ABSTRACT FROM AUTHOR]