湿法消解-电感耦合等离子体质谱法同时测定水生蔬菜中5种元素

目的　建立湿法消解/电感耦合等离子体质谱法（inductively coupled plasma mass spectrometry, ICP-MS）测定8种水生蔬菜中5种元素的方法。方法　样品在混合酸（硝酸+高氯酸=4+1, V/V）介质中消解，消解后，将消化液用水转移至25 mL容量瓶，并用ICP-MS同时测定水生蔬菜中总As、Cd、Cr、Ni和Pb这5种元素的含量。结果　5种元素的标准曲线线性范围可达0μg/L~200μg/L，相关系数：0.9992~0.9998，检出限：0.009 μg/L~0.025μg/L，定量限：0.030μg/L~0.083μg/L，回收率：89.4%~112.6%，RSD(n=11)：1.20%~1.86%。80份水生蔬菜样品中5种元素的含量均低于国家标准规定的食品中污染物限量。水生蔬菜不同种类间，5种元素的含量有显著差异。结论　湿法消解/ICP-MS方法直观、快速、准确、可靠，适于水生蔬菜中多元素同时测定。     

Application of Cudrania tricuspidata leaf extract as a washing agent to inactivate Listeria monocytogenes on fresh-cut romaine lettuce and kale

The present study aimed to examine the antimicrobial activity of silkworm thorn (Cudrania tricuspidata) leaf extract (CTLE) and its application as a washing agent for fresh-cut romaine lettuce and kale. The antimicrobial activities of CTLE at various concentrations against Listeria monocytogenes were determined using disc diffusion and viable cell count assays, and CTLE exhibited strong inactivation of L. monocytogenes. In particular, after the treatment with 0.4% CTLE, the protein content of L. monocytogenes cells was significantly (P < 0.05) decreased from 507.21 to 254.58 μg mL⁻¹, and damaged cells were observed by scanning electron microscopy. CTLE washing resulted in approximately 2-log reduction of microbial growth, similar to that of 0.01% NaOCl. In addition, CTLE washing did not affect the quality of romaine lettuce and kale. Therefore, these results suggest that CTLE is applicable as a new washing agent for inactivating L. monocytogenes on fresh-cut romaine lettuce and kale.     

4种常见果蔬保鲜运输超声波加湿的生命周期模拟研究

通过生命周期评估显示:与传统供应链相比,超声波加湿可将部分水果和蔬菜的环境影响(包括气候变化影响)降低23%,当加湿器应用于果蔬供应链,且总固有损失>24%时,加湿器的加入能使损失减少20%以上,说明超声波加湿技术能使果蔬供应链管理更具可持续性。     

Comparison of food values for consumers’ preferences on imported fruits and vegetables within Japan,Taiwan, and Indonesia

International agricultural trade in fruits and vegetables has received much attention as an effective method to create a sustainable agriculture industry for a country. This study focuses on consumers’ perceptions of food values toward imported fruits and vegetables in Japan, Taiwan, and Indonesia by using the Best-Worst Scaling method. Seven food values were examined in this study: labeling product origin, food safety certification, high quality appearance, domestic rarity, price, how the product was grown, and freshness. An online survey was conducted and 1,350 total valid respondents were collected (500 Japanese, 333 Taiwanese, and 517 Indonesian). The Latent Class Multinomial Logit model was used to analyze consumers for each country. Results revealed that food safety certification and freshness were found as the most important and second most important food values for the majority group of consumers in each of these three countries, respectively. However, the remainder of food values do not have the same importance for each country. The study should help governments and international marketers enhance their agricultural trade policies and marketing strategies for these targeted markets.     

发酵十字花科蔬菜中硫代葡萄糖苷代谢研究进展

硫代葡萄糖苷（简称硫苷）是十字花科蔬菜中一类重要的次生代谢物。在蔬菜发酵过程中，硫苷被代谢为异硫氰酸盐等活性产物，这些代谢产物具有抗氧化、抗癌、调节肠道菌群等多种生理功能。乳酸菌发酵对硫苷的代谢机制包括促进硫苷从蔬菜中释放，以及使其发生降解，且代谢作用既与乳酸菌种属相关，也与发酵体系的盐含量、金属离子、pH值以及蔬菜加热预处理相关。通过总结梳理发酵蔬菜硫苷代谢研究进展，并解析影响因素，为提高发酵蔬菜中活性硫苷代谢产物含量，提升发酵蔬菜的健康效应提供理论指引。     

果蔬中外泌体样纳米颗粒的分离、表征和应用研究进展

果蔬中的外泌体样纳米颗粒（exosome-like nanoparticles，ELNs）是由果蔬细胞释放的纳米级囊泡结构，与动物的外泌体具有类似的超微结构，但其脂质、蛋白质及核酸等化学成分具有显著差异，并具有独特的生物学功能。本文综述了2013年以来数十种果蔬中ELNs的相关研究进展，对其提取方法和表征手段进行了分析，重点分析了不同植物来源的ELNs中脂质、蛋白质和核酸类化学成分的组成差异，并对ELNs的潜在生理活性和载体功能进行了探讨，可为果蔬中ELNs的相关研究提供借鉴和启示。     

Influence of physical and biological variability and solution methods in fruit and vegetable quality nondestructive inspection by using imaging and near-infrared spectroscopy techniques: A review

Over the past decades, imaging and spectroscopy techniques have been rapidly developing and widely applied in nondestructive fruit and vegetable quality assessment. The physical properties (including size, shape, color, position, and temperature) and biological properties (including cultivar, season, maturity level and geographical origin) of fruits and vegetables vary from one to another. A great variety of physical and biological properties of agricultural products influence the optical propagation properties and interaction behaviors with incident light, thus decreasing the quality inspection accuracy. Many attempts have been made in image correction and spectral compensation methods to improve the inspection accuracy. This paper gives a detailed summary about influence of physical and biological variability, as well as the correction and compensation methods for eliminating or reducing the effects in fruit and vegetable quality nondestructive inspection by using imaging and spectroscopy techniques. The advantages and disadvantages of the solution methods are discussed and summarized. Additionally, the future challenges and potential trends are also reported.     

果蔬燕麦食品营养与开发利用进展

燕麦片是一种营养丰富、方便快捷、易于携带的食品。燕麦食品能基本满足人体所需能量,但维生素和矿物质等成分相对不足,不能满足机体一餐的全部营养需求。果蔬是人体获取维生素、矿物质和膳食纤维的主要来源,与人体健康密切相关,早餐合理摄取一定量的果蔬是身体健康的重要保证。果蔬燕麦食品的开发,能更好地满足人体对营养的需要,为人们提供了更好的早餐选择。本文综述了燕麦的营养保健功能、果蔬燕麦片的开发优势,并对其未来发展趋势进行了阐述,以供果蔬燕麦食品的研究和开发提供参考。     

QuEChERS-超高效液相色谱-串联质谱法同时测定蔬菜中30种农药残留

目的应用超高效液相色谱-串联质谱法同时测定蔬菜中30种农药残留。方法蔬菜样品经粉碎后,乙腈超声提取,采用简化的QuEChERS法净化,超高效液相色谱-串联质谱仪检测。结果 30种农药在相应浓度范围内线性良好,相关系数r为0.9991～1.0000,在所添加的3个水平浓度下,方法平均回收率为70.6%～102.6%,相对标准偏差为0.3%～9.6%。结论方法操作简便,灵敏度高,分离效果好,回收率高,30种农药的检出下限均低于国家标准,可应用于实际蔬菜样品中多农药残留的同时检测。