Cucumbers produce by-products such as cucumber pomace during processing and most of them are discarded without being utilized. To effectively utilize the waste, cucumber pomace is used to extract both insoluble and soluble dietary fibers (DFs) using compound enzyme method (ME), High pressure processing assisted ME (HPP-ME), and dynamic high-pressure microfluidization-assisted ME (DHPM-ME). The results showed that DHPM-ME improved the extraction rate of soluble DFs most effectively, increasing it from 1.74 % to 4.08 %. The modified DFs exhibited enhanced hydration properties and functional properties after HPP-ME- and DHPM-ME-mediated auxiliary treatment. Additionally, the modified DFs exhibited improved thermal stability, increased absorption peaks in the infrared spectra, decreased crystallinity, improved glucose and cholesterol adsorption ability, and delayed glucose adsorption. The cucumber pomace-derived modified DFs can be used as a functional food additive in bakery, meat, dairy products, and beverages, and their effective use can further enhance the economic benefits.
Pan Tao,Kaixin Ge,Xing Dai,Danni Xue,Yang Luo,Shixun Dai,Tiefeng Xu,Tao Jiang,Peiqing Zhang
Surface-enhanced Raman scattering (SERS) has great potential in the field of rapid detection of pesticide residues in food. In this paper, a fiber optic SERS sensor excited by evanescent waves was proposed for efficient detection of thiram. Silver nanocubes (Ag NCs) were prepared as SERS active substrates, which had much stronger electromagnetic field intensity than nanospheres under laser excitation due to much more “hot spots”. By using the method of electrostatic adsorption and laser induction, Ag NCs were uniformly assembled at the fiber taper waist (FTW) for enhancing the Raman signal. Different from the traditional way of stimulation, evanescent wave excitation greatly increased the interaction area between the excitation and analyte, while reducing the damage of the excited light to the metal nanostructures. The methods proposed in this work have been successfully used to detect the pesticide residues of thiram and showed good detection performance. The detection limits for 4-Mercaptobenzoic acid (4-MBA) and thiram were determined to be 10–9 and 10–8 M, the corresponding enhancement factor could be 1.64 × 105 and 6.38 × 104. Low concentration of thiram was detected in the peels of tomatoes and cucumbers, indicating its feasibility in actual sample detection. The combination of evanescent waves and SERS provides a new direction for the application of SERS sensors, which had great application potential in the field of pesticide residue detection.
危险品化学品经营许可证（带存储）