五种枣成分及功能研究

对五种枣的主要成分、无机元素、维生素以及总酚含量进行分析研究,并探讨总酚含量与抗氧化的关系.五种枣中总糖含量为80.86%～85.63%,还原糖含量为57.61%～77.93%,纤维素含量为6.13%～8.90%,蛋白质为4.75%～6.86%,脂肪含量为0.37%～1.02%,金丝小枣非还原糖的含量较高,其蛋白质和灰分的含量较低,故适合作为提取枣多糖的原料.五种枣中钾、钙、镁的含量较高,铁、钠、锌、铜的含量较低,硒未检出.五种枣中总酚含量为5.18～8.53mg/g,其中牙枣和尖枣因总酚含量较高,故适合作为提取酚类化合物的原料;五种枣的总酚含量与总的抗氧化能力没有相关性.     

Nutritional composition of five cultivars of chinese jujube

The proximate composition of five cultivars of Chinese jujube, along with mineral, vitamin and total phenolic contents were determined. Investigations showed that Chinese jujube contained 80.86–85.63% carbohydrate, 57.61–77.93% reducing sugar, 0.57–2.79% soluble fibre, 5.24–7.18% insoluble fibre, 4.75–6.86% protein, 0.37–1.02% lipid, 17.38–22.52% moisture and 2.26–3.01% ash. The soluble sugars of Chinese jujube included fructose, glucose, rhamnose, sorbitol and sucrose. Fructose and glucose were identified as the major sugars while sorbitol was present in much lesser amounts. Potassium, phosphorus, calcium and manganese were the major mineral constituents in Chinese jujube. Iron, sodium, zinc and copper were also detected in appreciable amounts. The contents of vitamin C, thiamine and riboflavin were found to be 192–359, 0.04–0.08 and 0.05–0.09 mg/100 g, respectively. Total phenolic contents ranged from 5.18 to 8.53 mg/g. No correlation between total phenolic contents and antioxidant capacities or antioxidant capacities and vitamin C contents of Chinese jujube was found.     

红外光谱技术在红枣农药残留检测中的研究进展

红枣是新疆特色林果的支柱产业,随着栽培面积的不断扩大,由于栽培生态的不同和病虫害的增加,致使农药的使用也越来越多,农药的滥用、误用、超量使用等不规范使用会导致红枣质量安全问题逐渐增多。基于红枣质量安全的关注及红枣中农药残留快速检测的需求,因红外光谱技术简单、快捷、经济、无损的特点,近年来国内外学者利用红外光谱技术对农产品中农药残留检测的可行性进行研究,验证红外光谱技术可用于农产品中农药残留检测分析,结合数据处理方法,化学计量学方法等可建立定性、定量分析检测模型。本文概述近年来红枣中农药的残留和检测现状以及红外光谱技术在农药残留检测相关领域的研究进展,并对红外光谱技术在农药残留检测中的应用发展进行展望。     

三种洋葱营养成分分析

对三种洋葱的主要营养成分、矿物质和黄酮类化合物含量进行分析研究,并探讨黄酮类化合物含量与抗氧化的关系。三种洋葱中水分含量为88.3%～92.7%,碳水化合物为7.73%～8.56%,蛋白质为1.12%～1.71%,脂肪为0.23%～0.41%,其中,白皮洋葱的脂肪含量较高,适合作为提取洋葱油的原料。三种洋葱中黄酮类化合物含量为592.3～913.2mg/kg,紫皮洋葱的黄酮类化合物含量最高,适合作为提取黄酮类化合物的原料,而且紫皮洋葱的产量较高,种植面积较大,很有开发前景;三种洋葱的黄酮类化合物含量与总的抗氧化能力没有相关性。三种洋葱矿物质元素组成相似,钾含量最高,铜含量最低。     

市售韭菜中农药残留及重金属污染状况

目的：科学管理湖南省韭菜食品安全。方法：对湖南地区690份韭菜样本中24项农药和5项重金属进行检测。结果：① 农药残留检出率为23.19%,检出率排名前3的农药分别为多菌灵、腐霉利和氯氰菊酯;农药残留的超标率为5.80%,其中腐霉利超标率最高,达2.61%。② 重金属元素检出率为77.68%,超标率为3.62%,其中检出率和超标率最高的重金属元素均为镉。结论：韭菜农药残留量较高,且重金属元素检出率远高于其农药残留检出率,其中,农药腐霉利和重金属镉为韭菜的主要超标项目,建议加强韭菜中农药残留及重金属污染的持续监测。     

Evaluation of pesticide residue dynamics in Chinese cabbage,head cabbage and cauliflower

ABSTRACT

Pesticide residues from the time of application until harvest were analysed for 20, 17 and 18 active insecticidal and fungicidal substances in Chinese cabbage, head cabbage and cauliflower, respectively. In total, 40 mathematical models of residue degradation were developed using a first-order kinetic equation, and from these models it was possible to forecast the action pre-harvest interval for a given action threshold for low-residue production in Brassica vegetables as a percentage of the maximum residue level. Additionally, it was possible to establish an action pre-harvest interval based on an action threshold of 0.01 mg kg^?1 for the production of Brassica vegetables for baby food. Among the evaluated commodities, the speed of residue degradation was highest in head cabbage, medium in Chinese cabbage and lowest in cauliflower. The half-lives of pesticide in various vegetables were also determined: they ranged from 1.55 to 5.25 days in Chinese cabbage, from 0.47 to 6.54 days in head cabbage and from 1.88 to 7.22 days in cauliflower.     

Bioactive compound content,antioxidant activity,deoxynivalenol and heavy metal contamination of pearled wheat fractions

Wheat kernels are rich in antioxidant compounds, that are mainly present in the outer bran layers and which are removed during milling. Unfortunately, several contaminants, e.g., mycotoxins and heavy metals, are also concentrated in the external layers. Pearling of 3 wheat varieties gave five fractions (each 5% of the original grain weight), starting from the outer layer until the inner kernel, designated as 0–5%, 5–10%, 10–15%, 15–20%, 20–25%, respectively. The remaining 75% of the inner kernel was also collected. Dietary fibre, free phenolic acids and total antioxidant activity decreased progressively from the external to the internal layers. However, the 5–10% fraction was richer in β-glucan content than the external one (0–5%). Heavy metals were only found in the most external fraction. Deoxynivalenol contamination decreased from the external to the internal layers: 64% of total contamination of kernel was found in the 0–5% and 5–10% fractions. The 10–15% kernel fraction offered the best compromise between high nutritional value and low contamination risk.     

河南省保健食品中污染物调查

目的了解保健食品中重金属、微生物及农药污染情况。方法样品为2008—2013年由保健食品生产、经营企业送检和监督部门抽检的产品共1 962份,采用GB/T 5009、GB 5009、GB/T 4789、GB 4789规定的方法,对2008—2013年河南省保健食品中的重金属、微生物、农药残留进行检测及分析。结果 6年间铅、砷、汞总超标率分别为6.67%(120/1 800)、6.12%(110/1 798)和1.32%(13/988),铅、砷年度超标率呈下降趋势,汞年度超标率差异无统计学意义(P0.05)。菌落总数、霉菌及酵母菌总超标率分别为5.25%、3.55%和0.32%,其年度超标率均呈下降趋势,大肠菌群年度超标率差异无统计学意义(P0.05)。铅、砷、汞、大肠菌群及霉菌超标主要集中于植物及动物类保健食品;铅、砷、汞、菌落总数、大肠菌群及霉菌超标率均以丸剂最高;植物类、动物类及营养素补充剂类保健食品的铅含量均值分别为0.71、0.74和0.31 mg/kg,砷含量均值分别为0.41、0.39和0.12 mg/kg,汞含量均值分别为0.07、0.04和0.03 mg/kg。致病菌未检出。检测377份样品的六六六、滴滴涕,均未超标。结论重金属污染较重,但超标率趋于下降,微生物存在不同程度污染但有所好转,植物类、动物类及丸剂保健食品风险较大;六六六、滴滴涕污染较低。     

五种枣提取物抗氧化活性的比较

研究了五种枣提取物的抗氧化活性,并与维生素E(VE)的抗氧化性相比较.结果表明:五种枣提取物抗氧化能力不同,五种枣提取物抗亚油酸过氧化能力、还原力、DPPH·清除率的强弱顺序相同,由强到弱依次为:金丝小枣、牙枣、尖枣、骏枣和三变红枣.其中金丝小枣、牙枣、尖枣抗氧化能力均大于VE.Duncan新复极差统计分析表明,金丝小枣、牙枣、VE之间的抗氧化能力存在显著性差异(P<0.05),而尖枣和VE之间没有显著性差异(P>0.05).此外,五种枣提取物的总酚含量与总的抗氧化能力没有相关性.     

Chemical composition,nutritional value and antioxidant properties of autochthonous Prunus avium cultivars from Campania Region

During a screening program aimed at the evaluation of antioxidative and antiproliferative properties, as well as nutritional properties of local edible plants, two endemic sweet cherry cultivars (‘Del Monte’ and ‘Della Recca’) were of interest. Macronutrient components (proteins, carbohydrates and lipids) of both the cherry cultivars were determined as well as free and total amino acids. Pomological traits were defined. HPLC–ESI/MSⁿ analysis, carried out on phenolic extracts properly prepared by extractive techniques from freeze dried fruits of both the cherry cultivars, showed that investigated cultivars differed in their colorless phenolic composition. Hydroxycinnamoyl quinic acid derivatives were present in both the cherry cultivars. ‘Della Recca’ cv. was particularly rich in 4-O-coumaroyl quinic and 5-O-caffeoylquinic acid, whereas quercetin-3-O-rutinoside was the main phenol compound of ‘Del Monte’ cultivar.The antiradical properties of the extracts were investigated by DPPH and ABTS methods. ‘Della Recca’ cv. cherries exhibited a pronounced antiradical activity: at 62.5 μg/mL dose level ABTS radical cation was converted in its reduced form by 88.7% and DPPH radical was reduced by 75.3%. The antiproliferative efficacy of ‘Della Recca’ and ‘Del Monte’ extracts were evaluated towards five cancer cell lines (HepG2, A549, HeLa, SK-B-NE(2)-C, and SH-SY5Y) through MTT assay. ‘Della Recca’ phenol extract showed a dose-dependent inhibiting activity towards cervical cancer HeLa cell line.     

五莲植烟土壤及烟叶中重金属、农药残留状况研究

采用定点调查方法研究了五莲植烟土壤、烟叶中重金属、农药残留状况。土壤中的铅、镉、汞、六六六的含量指标低于土壤自然背景值,大部分土壤中的滴滴涕含量也低于土壤自然背景值。烟叶中铅、镉、汞含量处于较低水平,有机氯、有机磷、拟除虫菊酯等杀虫剂、杀菌剂烟叶中残留普遍较低,部分有机磷杀虫剂残留相对较高。五莲烟区具有发展低残留优质烟叶的优越自然条件,但需进一步规范农药的使用。     

Proximate and heavy metal composition in chicken meat and tissues

Three different aged groups (4-week, 8-week and 18-week) of chickens were obtained from Manisa (in Turkey) Poultry Diseases Research and Vaccine Production Institute. Eleven metals (Cd, Ca, Cu, Fe, Pb, Mg, Mn, Hg, K, Na and Zn) and one non-metal (P) (heart, gizzard, livers, kidneys and spleens and some mineral matter in chicken tissues and meats) were determined using atomic absorption spectrophotometry. A flame photometer was used for determinations of sodium and potassium. After oven-drying of samples, P was determined by a colorimetric method. Proximate and mineral composition of heart, gizzard and meat from different aged group chickens were determined. It is concluded that there is wide variation in metal contents of these tissues.     

澳洲坚果粕营养成分测定与氨基酸组成评价

目的:研究分析澳洲坚果粕营养成分的含量与组成。方法:采用氨基酸自动分析仪、凯氏定氮法及蒽酮-硫酸法等方法对澳洲坚果粕中的氨基酸、蛋白质、碳水化合物等营养成分进行了测定。应用氨基酸比值系数法,以WHO/FAO氨基酸参考模式为评价标准,对必需氨基酸的组成进行了评价。结果:澳洲坚果粕含脂肪17.22%、蛋白质24.90%、碳水化合物24.78%、氨基酸17种,总量为17.84%。其必需氨基酸的构成比例基本符合食品法典委员会(FAO/WHO)的标准,氨基酸的比值系数分(SRC)为86.95。结论:澳洲坚果粕营养丰富,人体必需氨基酸种类齐全,配比均衡,是有利于人体氨基酸营养平衡的优质食品原料。     

Gross composition,amino acid,phytic acid and trace element contents of thirteen cowpea cultivars and their nutritional significance

Thirteen cultivars of cowpea (Vigna unguiculata (L) Walp) were analysed for their proximate composition, amino acid, trace element and phytic acid contents. Crude protein values ranged from 206·8 to 283·8 g kg^?1 DM. The mean contents (g kg^?1) of other major nutrients were ether extract, 18·6; ash, 38·8; total dietary fibre, 121·8 and carbohydrates, 573·4. When compared with the provisional amino acid scoring pattern of FAO, all cultivars were low in methionine and high in lysine, isoleucine, leucine and phenylalanine plus tyrosine. Values for threonine and valine were variable compared with the pattern. The range of values for the chemical score was 0·61–0·74. Phytic acid values ranged from 5·10 to 10·27 g kg^?1, and the phytate: zinc molar ratios were all higher than that (15:1) above which zinc deficiency can be induced. Most of the trace elements showed wide variation in their occurrence among the cultivars. The values for zinc and iron showed less variation. The toxic elements mercury and selenium were present in varying amounts in more than half of the cultivars while tin was found in only one variety.     

西藏察隅龙爪稷营养成分、重金属含量与农药残留分析

以西藏察隅龙爪稷为研究对象,对其营养成分、重金属含量与农药残留进行测定,并采用国际通用的评价方法对其营养进行评价。结果表明:龙爪稷籽粒蛋白质含量7.31%,脂肪含量1.2%;矿物质元素K、Ca、Mg、Fe、Zn含量分别为3 281.8 mg/100 g、2 259.5 mg/100 g、1 403.9 mg/kg、15.2 mg/kg与13.9 mg/kg,高于普通谷物;龙爪稷含有18种氨基酸,其中必需氨基酸8种,占氨基酸总量的39.80%,必需氨基酸评分60,必需氨基酸指数87.26,第一限制性氨基酸为赖氨酸;此外,龙爪稷中重金属As、Hg、Pb、Cd均未检出,188种农药未检出,食用安全性高。     

纤维素酶-木聚糖酶对红枣渣膳食纤维的酶法改性

以红枣渣为原料,分别探讨了纤维素酶和木聚糖酶单酶加酶量、酶解时间、酶解温度、酶解pH对红枣渣可溶性和不溶性纤维得率的影响;在此基础上,以2种酶的添加量和酶解时间为变量,利用多因素复合试验设计原理和分析方法,得到枣渣纤维的酶法改性的最佳条件为:纤维素酶添加量0.29%、木聚糖酶添加量0.21%、酶解时间49.23 min。通过酶法改性,可将枣渣纤维的可溶性纤维的比例由6.79%提高到10.15%,以使可溶性纤维与不溶性纤维接近1∶3的最佳比例。     

9种药食同源物质重金属及农药污染状况Meta分析

目的 对杜仲叶、党参、肉苁蓉、铁皮石斛、黄芪、西洋参、天麻、灵芝及山茱萸9种试点药食同源物质重金属及农药污染水平和现状进行Meta分析。方法 检索PubMed、中国知网、维普及万方数据库,获取2000—2022年发表的9种药食同源物质中重金属、农药、环境污染物研究文献,根据文献纳入排除标准进行筛选,对纳入的文献采用Meta法进行分析。结果 本研究共纳入106篇文献,涉及来自23个省（市）9种药食同源物质中铅（Pb）、镉（Cd）、汞（Hg）、砷（As）、铬（Cr）、铜（Cu）及镍（Ni）7类重金属,有机氯类、拟除虫菊酯类和有机磷类等42种农药。9种药食同源物质重金属污染合计均值为0.22 mg/kg（95%CI：0.13~0.39）,其中杜仲叶重金属污染合计均值最高,为2.80 mg/kg（95%CI：0.75~10.37）,其次为铁皮石斛,合计均值为0.30 mg/kg（95%CI：0.18~0.49）,其余7种药食同源物质中重金属合计均值均低于0.30 mg/kg;7类重金属中铜污染水平最高,其次为镉和铅,亚组分析表明不同产地的药食同源物质中7类重金属污染水平具有较高的异质性（P<0.05）。42种农药污染水平均值存在异质性（P<0.05）,铁皮石斛、西洋参、肉苁蓉、黄芪及天麻5种药食同源物质中五氯硝基苯、六六六、滴滴涕残留量合计均值位列前3。结论 不同药食同源物质重金属及农药污染类别及污染水平存在差异,重金属污染与产地和药食同源物质种类有关,部分药食同源物质中可检出禁用农药,应进一步加强药食同源物质污染物溯源分析,同时加大对药食同源物质生产加工监管和监测力度。     

Physicochemical,morphological, and thermal properties of starches separated from bulbs of four Chinese lily cultivars

The starches separated from bulbs of four different lily cultivars (Lanzhou, Pinglu, Yixing‐1, and Yixing‐2) were investigated for physicochemical, morphological, crystalline, and thermal properties. AM content of lily bulbs starches from different cultivars ranged from 19.46 to 25.17%. The swelling power of starches ranged between 14.4 and 21.3 g/g, and the solubility ranged from 8.92 and 16.6% at the temperature of 85°C. Four cultivars of lily starches paste had excellent transparency and the transmittance value of Lanzhou lily as high as 54.7%. The transmittance of the gelatinized aqueous starch suspensions, from all lily cultivars, decreased with increase in storage period. The shape of starch granules varied from triangular to cylindrical and XRD of four lily starches all showed B‐type pattern. The transition temperatures and enthalpy of gelatinization (ΔH_gel) were determined using DSC. T_p varied from 62.52 to 65.25°C. Pinglu lily starch showed the highest ΔH_gel and gelatinization range (T_c–T_o) index among starches from four different lily cultivars.