Distribution pattern of eight heavy metals in the outer and inner tissues of ten commonly used vegetables

This study reports the distribution of eight heavy metals (Cd, Co, Cr, Cu, Hg, Mn, Ni, and Pb) in the outer and inner tissues of ten different vegetables from the Qassim region of Saudi Arabia. The oven-dried (65°C, 48 h) vegetable samples were subjected to microwave acid digestion before heavy metals analysis using inductively coupled plasma optical emission spectrometry. The results showed that Co, Cd, and Pb were absent in the outer tissues of all the vegetables, whereas these elements were detected in the inner tissues of some vegetables in the ranges of 0.01–0.23 mg/kg wet weight, 0.03–0.42 mg/kg, and 0.02–3.44 mg/kg, respectively. The traces of Hg (1.83–3.59 μg/kg) were noticed in the outer tissues of all the samples; however, it was not detected in the inner tissues of vegetables. The variable distribution of heavy metals in different vegetables is influenced by several factors, including exposure route, physicochemical properties of heavy metals, species of crops, cultivation strategy, soil type, and growing conditions. In conclusion, although the representative samples of vegetables used in this study contained safe levels of Cd, Co, Ni, and Pb, higher than recommended upper limits of Cr, Cu, and Mn were observed in some vegetables. These findings suggested that regular monitoring of heavy metals in vegetables is important to safeguard consumers.     

蔬菜中镉的氢化物-原子荧光光谱法测定

本文采用氢化物—原子荧光光谱法测定蔬菜中镉,具有操作简单、快速、基体干扰少、灵敏度高等优点。方法检出限为O.17μg/L,线性范围为(0～60.0)μg/L。     

谷物与蔬菜复合食品的研究开发现状及展望

对以谷物和蔬菜为主要原料的复合食品现状进行综述,初步阐述了这类复合食品的营养价值、应用前景及发展思路。     

数种果蔬的抗氧化活性评价

测定了华南地区常见的38种果蔬的抗氧化活性值和总酚含量,并比较了两者的相关性。结果表明：大多数果蔬都具有一定的抗氧化活性,其中,姜、紫包菜、香蕉、草莓、乌榄的抗氧化活性较强。38种样品的水溶性总酚含量在15.37-339.48mg/100g之间。全体样品的抗氧化活性值与总酚量的相关系数r=-0.58;叶绿素类r=-0.59;胡萝卜素类r=-0.41;类黄酮类r=-0.81;其它样品r=-0.42,由此说明果蔬抗氧化活性的强弱与果蔬所含特征成分具有较大的关联性。     

Convenience may increase vegetable intake among young consumers

Current food trends such as healthy eating, plant-based diets and sustainability encourage consumers to eat more vegetables. However, it is a challenge for many, including the younger generations, to meet the dietary recommendations regarding vegetable intake. The purpose of this study was to investigate if vegetable convenience products can increase the daily intake of vegetables among young consumers. A total of 100 participants were randomly allocated to receive either regular or convenience vegetables for a week and filled in questionnaires about vegetable use and consumption before after the intervention. Results showed that participants who received convenience vegetable products significantly increased their daily vegetable consumption by 19% (p = 0.005), but there was no significant difference between the groups during the intervention period. Furthermore, convenience vegetable products were used and perceived differently from regular vegetables. It was found that especially the preparation of the convenient vegetable products had an impact on how the products were perceived. Participants indicated that they were not willing to buy or pay more for convenience in relation to vegetables. In conclusion, convenience vegetable products may increase vegetable intake among young consumers. However, this specific consumer group may find barriers within their values regarding food, consumerism and sustainability, which prevent them from buying convenience food products.     

I、Ba、Sr、Y和Zr从土壤至蔬菜的转移系数

采用放射性同位素示踪法及元素含量分析法确定出Ｉ、Ｂａ、Ｓｒ、Ｙ和Ｚｒ从土壤到多叶蔬菜的转移系数，并研究了蔬菜生长期、棵株大小、核素在土壤中的含量、环境条件等因素对转移系数的影响     

Anti- and pro-oxidant activity of Cichorium genus vegetables and effect of thermal treatment in biological systems

The antiradical activity of water soluble components in six vegetables belonging to the Cichorium genus, i.e., three cultivars of red intybus species var. silvestre (Treviso, Chioggia, Verona red chicories), a white intybus species var. foliosum (Belgian chicory), and two vegetables of the endivia species var. latifolium (escarole chicory) and var. crispum (“crispa” chicory), were studied using two biological systems consisting of: (1) microsome membrane rat hepatocyties in which oxidative damage was induced by CCl₄; (2) gram-positive bacterium, Staphylococcus aureus cultures, subjected to damage with cumene hydroperoxyde. The obtained results show that in both systems the red vegetables possess the strongest antioxidant properties and contain different antioxidant compounds whether at a low or high molecular weight, but only those of high molecular-weight (MW > 3500 Da) are able to act as antioxidants in all the used systems. The lower MW fraction (MW < 3500 Da) showed itself to be pro-oxidant in the microsome system. The effects of thermal treatments such as boiling, freezing and freeze-drying were also investigated.     

Chemistry of sulphur dioxide in vegetable dehydration

The state of sulphur dioxide in partially dehydrated or dehydrated foods is complex and depends on pH, ionic strength, water activity and concentration, and on the effects of anions and cations on the solubilities of sulphite and disulphite salts. The chemical basis of the preservative action is explained in terms of the nucleophilicity of the sulphite ion and the possible consequences of the changing state of the additive during dehydration are evaluated. The significance of autoxidation of the sulphite ion to its fate in food, and role as an antioxidant, or prooxidant, is critically discussed. The most widely studied reaction of sulphur dioxide in food is its inhibition of non-enzymic browning; the current state of knowledge concerning the mechanism of this action is explained.
The loss of sulphur dioxide during vegetable dehydration obeys first-order kinetics. This observation is considered in terms of known first-order reactions in foods and processes which are limited by rate of diffusion. There are still insufficient data to suggest ways in which the composition of the food could be altered to reduce its requirement for sulphur dioxide during dehydration.     

保鲜技术在鲜切果蔬中的应用

简要介绍了鲜切果蔬的发展现状,重点分析了鲜切果蔬常见的保鲜技术及存在的问题,提出了新型保鲜技术在鲜切果蔬的应用构想,展望了鲜切果蔬的应用前景。     

检测霜霉威的两种方法的比较

目的比较胶体金法与液相色谱-质谱质谱联用法(LC-MS/MS)在霜霉威检测中的应用。证实胶体金试纸检测蔬菜中霜霉威残留的可靠性,并以此为基础建立一个新的检测手段。方法通过胶体金试纸条半定量方法检测的试样,再用液/质谱法联用定量检测试样中的霜霉威。结果胶体金试纸检测为阴性的100个试样,经液/质谱法联用检测结果为未检出,符合率为100%。添加霜霉威的胶体金试纸检测阳性的试样经液/质谱法联用检测,符合率为100%,添加的Cutoff值样品回收率达到93%。结论与液/质联用检测法相比较,胶体金法检测霜霉威具有操作简便、观察直观、快速、省时的特点,特异性强、敏感性较高,从而为检测霜霉威提供了一种快速的检测方法。