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In an effort to provide a theoretical basis and data reference for the efficient processing and utilization of peanuts, changes in the moisture content, browning degree, particle texture parameters, water state and distribution, and protein denaturation degree of peanuts before and after microwave pretreatment were investigated, as well as the effect of microwave pretreatment on the yield of screw-pressed peanut oil. The results were compared with those obtained using vacuum oven drying. Meanwhile, for each pretreatment, the Pearson correlation between oil yield and moisture content, browning index (BI), particle texture parameters, water state, and protein denaturation degree was determined. The results showed that after microwave treatment for 7 min at 900 W or vacuum oven treatment at 85 ℃ for 89 min, the moisture content of peanuts decreased from 5.25% to 2.27%, with the highest oil yields of 45.85% and 45.76% being obtained, respectively. Under these conditions, the shear stress formed between peanuts and the oil press was moderate, peanuts were fully squeezed and deformed, with a large amount of oil flowing out, and peanuts had the best plasticity, the most ideal moisture state and a moderate degree of protein denaturation, so that not only a large amount of oil flowed out, but also peanuts were not easily broken, thus not affecting the formation of peanut cake.

In this study, the flavor components of double-low fragrant rapeseed oils (cv. “Zhongyouza 19”) from nine different planting areas were qualitatively and quantitatively analyzed by headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry coupled with olfactometry (GC-MS-O). The results showed that a total of 63 aroma-active compounds were identified using two columns (polar and non-polar) at a total concentration of 222.0 to 468.9 mg/kg. The total concentration of aroma compounds was highest in the Hunan sample and lowest in the Jiangxi sample. Out of the identified flavor substances, 38 had odor activity value (OAV) greater than 10. The results of partial least squares-discriminant analysis (PLS-DA) and sensory evaluation showed that 2-methylpyrazine, 2,3,5-trimethylpyrazine, and 2-methyl-3,5-diethylpyrazine were the main contributors to roasted aroma notes, 3-butenylisothiocyanate provided spicy notes, and 5-hexenenitrile and 4-methylthionitrile led to green notes. Based on variable important in the projection (VIP) values, nine key differential substances were selected, namely, methanthiol, 2-methylpyrazine, 2,3-diethyl-5-methylpyrazine, dimethyl disulfide, 5-methylthiopentonitrile, 5-hexenenitrile, (E,Z)-2,4-pentadienonitrile, hexanal and dimethyl trisulfide. They could be considered as potential flavor markers for the discrimination of double-low fragrant rapeseed oils from different planting areas. This research can provide a theoretical guide for the screening of raw materials for fragrant rapeseed oils.

Abstract This study investigated the effect of different almond oil extraction techniques, namely, cold‐press extraction (CP), hydraulic press extraction (HP), and subcritical fluid extraction (SFE), on the fatty acid composition, physicochemical properties, bioactive substances, and thermal stability. The results showed that oleic acid and linoleic acid were the main unsaturated fatty acids in almond oil (AO). The overall physicochemical properties of the AO (SFE) had the better oil quality compared to cold‐press extraction and hydraulic press extraction in three kinds of varieties. Almond oil extracted from SFE contained the highest levels of total phenolics (9.58–11.75 mg/100 g), total phytosterols (92.86–244.21 mg/100 g), total tocopherols, and tocotrienols (48.03–55.74 mg/100 g). Meanwhile, the TG/DTG curves showed AO (SFE) were more thermally stable than AO (CP) and AO (HP) consistent with the result of oxidative induction time. Subcritical fluid extraction may be a useful extraction technology to produce high‐quality almond oils in the future.

Summary: There was an extensive interest in food‐grade Pickering emulsions formulated by natural stabilisers owing to the gradual growing demand for pursuing green‐label products. Based on this, the desalted duck egg white nanogels (DEWN) combined with κ‐carrageenan (CAR) (CAR/DEWN) were used as stabilisers to prepare environment‐friendly Pickering emulsions. The DEWN and CAR/DEWN as well as the particles‐stabilised emulsions were all characterised. Compared with the DEWN‐ and CAR‐stabilised emulsions, Pickering emulsions based on CAR/DEWN were investigated to illustrate the long‐term stability according to the results of visual appearance, static multiple light scattering and centrifugation experiments. In addition, CAR/DEWN could prepare stable high internal phase emulsions, which may give a new perspective for nutraceutical or drug encapsulation and delivery. Adding CAR to the DEWN not only increased the apparent viscosity of the emulsions to 122.2% but also enhanced the thixotropic recovery rate to 87.7%. In general, CAR/DEWN as stabilisers significantly promoted the Pickering emulsions' properties, and provided a possibility for the application of Pickering emulsion in foods. [ABSTRACT FROM AUTHOR]

α‐Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α‐amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non‐destructive sensing of α‐amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ‐cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ‐cyclodextrin, but the AIE residues can be released in to water after the α‐amylase hydrolysing γ‐cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL−1 in MES buffer with a linear range of 0–0.35 U mL−1, having excellent selectivity to α‐amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α‐amylase in human serum, showing potential in point of care testing. How to be a good guest: A supramolecular probe based on the tetraphenylethylene motif and γ‐cyclodextrin host–guest inclusion for α‐amylase recognition was designed and synthesized. The specific cleavage of the 1,4‐glycosidic bonds in cyclodextrin by α‐amylase results in the release of the guest molecule TPESO3Na, a relatively amphiphilic moiety that self‐assembles into a highly fluorescent micelle, thus giving rise to "turn‐on" fluorescent signals. [ABSTRACT FROM AUTHOR]

The double-low rapeseed contains ≤2% erucic acid in its oil and ≤35μmol/g of dry meal. The oil of double-low rapeseed contains very low levels of saturated fatty acids (6%), high levels of oleic acid (≥60%), and intermediate levels of linoleic and linolenic acids (20 %and 10 %, respectively). Because of its higher oil content and numerous agricultural advantages, double-low rapeseed is getting worldwide attention. The rapeseed oil, which was extracted by a traditional process with pre-press and solvent extraction, is of bad quality. Commercial hexane, which has been used as a solvent for crude edible oil extraction, has toxicological and environmental safety issues. Carbon dioxide in its supercritical state has properties and extraction capacities very similar to liquids. Supercritical carbon dioxide extraction is a new technique for oil extraction and is similar to conventional solvent extraction in that the material to be extracted is withdrawn from the substrate by using a solvent. In its supercritical state, carbon dioxide is the most commonly used supercritical solvent due to its nontoxicity, non-flammability, low cost, availability in bulk quantities, ease of removal from the extracted materials, and low critical temperature and pressure (31.06 °C and 7.38 MPa, respectively). To improve the additional value of oils and meals obtained from the cold press cake of double-low dehulled rapeseed, supercritical CO2 is used to extract double-low rapeseed oil and then the quality of the oil and meal obtained is studied. The affection of factors, which includes extraction pressure, temperature, and time effecting on oil yield, is investigated by Box-Behnken's response surface methodology. The model equation for predicting the optimum response values is established by Design Expert software. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation. The experiment result indicates that affection of extraction pressure and time on oil yield are more significant than extraction temperature. The interaction between extraction pressure and time has a very significant affection on oil yield. The optimum operation parameters of supercritical CO2 extraction are: extraction temperature 40°C, pressure 28MPa, and time 120min.In this optimal condition, the oil yield is 95.08% and is similar to the 95.30% predicted as maximum oil yield by the mathematical model under the condition of temperature 39.66°C and pressure 27.50MPa with extraction time 120 min. The supercritical CO2 extraction of double-low rapeseed oil from dehulled cold press cake has a lighter color and better acid and peroxide value compared to n-hexane extraction. The phospholipid content of oil extracted with supercritical CO2 is 0.051mg/g, which is 1/32 of the n-hexane process, and the vitamin E and total phenolic content are 17.68ug/g and 5.17ug/mL respectively, which are both larger than the n-hexane extraction process. The meal of double-low rapeseed obtained from dehulled cold press cake with supercritical CO2 extraction, which has a superior quality compared to the meal obtained by n-hexane extraction, has lower glucosinolate content, high protein solubility, and better color. These study results can help utilize cold press cake of dehulled double-low rapeseed for high-value purposes. [ABSTRACT FROM AUTHOR]

The double-low rapeseed contains ≤2% erucic acid in its oil and ≤35μmol/g of dry meal. The oil of double-low rapeseed contains very low levels of saturated fatty acids (6%), high levels of oleic acid (≥60%), and intermediate levels of linoleic and linolenic acids (20 %and 10 %, respectively). Because of its higher oil content and numerous agricultural advantages, double-low rapeseed is getting worldwide attention. The rapeseed oil, which was extracted by a traditional process with pre-press and solvent extraction, is of bad quality. Commercial hexane, which has been used as a solvent for crude edible oil extraction, has toxicological and environmental safety issues. Carbon dioxide in its supercritical state has properties and extraction capacities very similar to liquids. Supercritical carbon dioxide extraction is a new technique for oil extraction and is similar to conventional solvent extraction in that the material to be extracted is withdrawn from the substrate by using a solvent. In its supercritical state, carbon dioxide is the most commonly used supercritical solvent due to its nontoxicity, non-flammability, low cost, availability in bulk quantities, ease of removal from the extracted materials, and low critical temperature and pressure (31.06 °C and 7.38 MPa, respectively). To improve the additional value of oils and meals obtained from the cold press cake of double-low dehulled rapeseed, supercritical CO2 is used to extract double-low rapeseed oil and then the quality of the oil and meal obtained is studied. The affection of factors, which includes extraction pressure, temperature, and time effecting on oil yield, is investigated by Box-Behnken's response surface methodology. The model equation for predicting the optimum response values is established by Design Expert software. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation. The experiment result indicates that affection of extraction pressure and time on oil yield are more significant than extraction temperature. The interaction between extraction pressure and time has a very significant affection on oil yield. The optimum operation parameters of supercritical CO2 extraction are: extraction temperature 40°C, pressure 28MPa, and time 120min.In this optimal condition, the oil yield is 95.08% and is similar to the 95.30% predicted as maximum oil yield by the mathematical model under the condition of temperature 39.66°C and pressure 27.50MPa with extraction time 120 min. The supercritical CO2 extraction of double-low rapeseed oil from dehulled cold press cake has a lighter color and better acid and peroxide value compared to n-hexane extraction. The phospholipid content of oil extracted with supercritical CO2 is 0.051mg/g, which is 1/32 of the n-hexane process, and the vitamin E and total phenolic content are 17.68ug/g and 5.17ug/mL respectively, which are both larger than the n-hexane extraction process. The meal of double-low rapeseed obtained from dehulled cold press cake with supercritical CO2 extraction, which has a superior quality compared to the meal obtained by n-hexane extraction, has lower glucosinolate content, high protein solubility, and better color. These study results can help utilize cold press cake of dehulled double-low rapeseed for high-value purposes. [ABSTRACT FROM AUTHOR]

α-Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α-amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non-destructive sensing of α-amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ-cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ-cyclodextrin, but the AIE residues can be released in to water after the α-amylase hydrolysing γ-cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL -1 in MES buffer with a linear range of 0-0.35 U mL -1 , having excellent selectivity to α-amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α-amylase in human serum, showing potential in point of care testing., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)