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Abstract: BACKGROUND: Vegetable proteins are increasingly used to stabilize oil‐in‐water (O/W) emulsions. However, emulsions are thermodynamically unstable. Recently, high‐intensity ultrasound (US) has been used to enhance the stability of emulsions. For these reasons, and considering almond (Prunus dulcis L.) as a good source of high‐quality proteins, the aim of this work was to investigate the effect of US treatment on the stability of pre‐emulsification O/W emulsions coated with almond protein isolate (API). RESULTS: The influence of API concentration (0.25–2.0 g L−1), ion strength (0–500 mmol L−1 NaCl), and pH (3.0–7.0) on the stability of US‐treated emulsions was evaluated. US treatment (200–600 W, 25 kHz, 15 min) led to a significant reduction in the particles size of droplets in emulsions, increased critical osmotic pressure and additional protein interfacial adsorption, and thus the formation of more stable emulsions. The more unfolded and random coil structures of the proteins were detected at higher US power, facilitating protein interfacial adsorption. Increasing API concentrations resulted in higher stability of US‐treated emulsions against untreated counterparts. The US‐treated emulsions were more resistant to salt than untreated samples. In the range from pH 3.0 to7.0, US treatment also enhanced the physical stability of emulsions compared with untreated emulsions. CONCLUSION: US technology could be applied to produce more stable O/W food emulsions stabilized by proteins. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In the present work, 116 samples were collected and near-infrared reflectance spectroscopy prediction model for determination of moisture, protein, and fat contents of walnut meal were obtained and evaluated. All the samples were analyzed based on the chemical methods. Meanwhile, they were scanned to obtain their near-infrared reflectance spectrum in the wavelength range of 570–1840 nm. Several preprocess treatments including scattering pretreatments, mathematical pretreatments, and aggression methods were optimized to increase the accuracy of the calibration models according to the coefficient of determination for calibration (Rc2) and the cross-validation (one minus the variance ratio, 1-VR), and the standard error of calibration and cross-validation. The results showed modified partial least square loading was the better aggression method to predict the moisture, proteins, and fats in walnut kernel. The calibration equations obtained indicated that near-infrared reflectance spectroscopy had excellent predictive capacity for the three components withRc2= 0.965, standard error of calibration = 0.052 for moisture, andRc2= 0.967, standard error of calibration = 0.191 for proteins, andRc2= 0.979, standard error of calibration = 0.171 for fats, respectively. The external validation further confirmed the robustness and reliability of the near-infrared reflectance spectroscopy prediction models with the correlation coefficient of actual and predicted values (R2) = 0.952, ratio of performance deviation = 4.14, the standard error of prediction =0.058 for moisture, andR2= 0.977, ratio of performance deviation = 5.55, standard error of prediction = 0.182 for proteins, andR2= 0.990, ratio of performance deviation = 8.64, standard error of prediction = 0.191 for fats, respectively. Near-infrared reflectance spectroscopy is a reliable technology to predict these constituents in walnuts. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of dihydric alcohol chain length (1,2-ethanediol, 1,3-propanediol, and 1,4-butanediol) on the structure of deep eutectic solvents (DESs) and the properties of the extracted oat proteins. Herein, five anhydrous and nine hydrated DESs were successfully prepared by mixing choline chloride, dihydric alcohol, and/or water in a heating method. The structures of DESs were confirmed by FTIR and 1 H NMR. Among them, only four anhydrous and six hydrated DESs were able to extract oat proteins from flours by one-step extraction. SDS-PAGE and FTIR analyses indicated that the structural properties of the oat proteins were highly reliant on the composition of the DESs; while physicochemical properties were primarily ruled by the environmental pH. Overall, the hydrated DES composing of all food-grade compounds, including choline chloride, 1,3-propanediol, and water at a molar ratio of 1:3:1, demonstrated its great potential for one-step biorefinery of oat proteins., (Copyright © 2021 Elsevier Ltd. All rights reserved.)