The effect of non-thermal (HPP and semi-HPP-CO 2 ) and thermal (flash pasteurization, FP) treatments on phytonutrients of flowable smoothie prepared from quadrable vegetable blends (FQVS) was investigated using multidimensional methods. First, FQVS gained an acceptability sensorial index (85.7%) compared with other formulas. FQVS/semi-HPP-CO 2 showed a greater microbial stability during storage (0–30 d) compared to HPP and FP. Fructose and glucose highly declined than sucrose in all smoothies, where semi-HPP-CO 2 steadily declined this reduction during storage. LC/MS-MS analysis showed that semi-HPP-CO 2 preserved most of FQVS's phytonutrients and their antioxidant effects measured by ORAC and oxidative enzymes inhibition assays. Semi-HPP-CO 2 acquired the lowest apparent viscosity among different FQVS smoothies, showing its post-processing flowability behavior. Most importantly, semi-HPP-CO 2 predicted a reduced power consumption for HPP and reduced the gas emission. In conclusion, blending different vegetables assisted with semi-HPP-CO 2 could be a novel approach to produce storage-stable smoothies with adequate amounts of phytonutrients and sensorial scores.
Guo-Ying CHEN,Hao ZHANG,Cong-Peng ZHAO,Chun-Yan ZHANG,Yuan WANG,Hua CHEN,Feng-Qing YANG
In this study, a capillary electrophoresis-based online immobilized acetylcholinesterase (AChE) microreactor was developed for the determination of organophosphorus pesticide (OPs) residues in six fruit and vegetable juice samples. AChE was immobilized on the inner wall at the inlet of the capillary via polydopamine (PDA) coating. The immobilized AChE activity and other kinetic parameters were evaluated by measuring the peak area of the product (thiocholine). The value of Michaelis-Menten constant ( K m ) was determined to be 3.11 mM, and the half-maximal inhibitory concentration (IC 50 ) and inhibition constant ( K i ) of tacrine on immobilized AChE were measured to be 0.46 μM and 0.27 μM, respectively. The activity of the immobilized AChE remained more than 85.0% of its initial immobilized enzyme activity after 30 runs. Then, the developed strategy was successfully applied to detect the acephate in six fruit and vegetable juice samples (apple, pear, peach, tomato, cucumber and lettuce juice) with a limit of detection (LOD) of 11.0 ng/mL. Results show that the recovery of spiked samples are in the range of 86.0-96.0% with RSD of less than 5.7%. Therefore, the proposed method is capable of achieving rapid analysis of acephate with simple operation when there are no other types of OPs in the real samples.
The functionalization of covalent organic frameworks (COFs) enhances chemical properties and expands future applications. Herein, a facile strategy for sulfoacid-functionalized COF is presented through post-modification of covalent triazine frameworks (CTFs) platform. The magnetic solid phase extraction (MSPE) material is obtained by anchoring in situ Ni particles on CTF support (Ni/CTF-SO 3 H) possessing a dual retention mechanism combining hydrophilic-lipophilic-balance (HLB) and cation-exchange interaction. We established the (Ni/CTF-SO 3 H)-MSPE method for selectively enriching carbendazim (CBZ) and thiabendazole (TBZ) from food samples and reducing matrix effect simultaneously. The method detection limit is 1.23–7.05 µg kg −1 for CBZ and TBZ in vegetable, fruit and juice samples, determined by high-performance liquid chromatography-ultraviolet detector. The recoveries of spiked CBZ and TBZ in the samples are 80.2–115.1% and RSDs 6.0–11.4%, depending on both analytes and samples. Our work provides a unique perspective in the development of functionalized COFs as a versatile HLB/cation-exchange mixed-mode SPE sorbent for extraction of basic analytes in complex matrix.
危险品化学品经营许可证（带存储）