Aflatoxins in black tea in Iran

Aflatoxins (AFs) are highly toxic, and carcinogenic secondary fungal metabolites and have been detected in various food commodities. In this regard, 40 black tea samples including domestic and imported black tea were analysed for aflatoxin contamination by high-performance liquid chromatography using a post-column derivatisation procedure (Kobra cell) with fluorescence detection. Samples were randomly collected in 2010 from Tehran markets. The results revealed that 30 among 40 samples were contaminated with aflatoxins (27.5% of the total). Mean AFB1 content was 10.0 ng/g and mean of aflatoxin total was 12.07 ng/g for the 11 contaminated samples.     

脂质体在食品中的应用及体外消化研究进展

脂质体是由双亲性物质如磷脂组成的内部为水相、具有类细胞膜结构的双分子层闭合囊泡,因其具有保护、运载、靶向和缓释等特点,目前已在食品营养、医药、化妆品、农业等领域表现出极大的应用潜能。本文简要介绍了脂质体的性质及特点,重点综述了脂质体在脂类、抗氧化剂、酶与蛋白质以及维生素和矿物质等食品领域的研究及应用,最后概述了脂质体作为食品营养因子运载体系在模拟体外胃和肠道消化的研究进展。     

食品中亲电物质的最新研究进展

食品中的亲电物质是高效低毒的核转录因子NF-E2相关因子2(Nrf2)诱导剂,通过Keap1/Nrf2/ARE通路激活Ⅱ相酶和抗氧化酶的转录。Ⅱ相酶和抗氧化蛋白可发挥慢速、长效的抗氧化和解毒作用。目前已经发现食品中有9类亲电物质,它们具有相似的结构特征。研究和开发食品中的亲电物质,将成为功能性食品新的研究领域。     

抗氧化成分在消化过程中变化的研究进展

食物中的抗氧化成分具有促进健康和预防非传染性疾病的作用,近年来得到学术界和工业界的广泛关注,然而目前的研究主要还是停留在对于提取物的活性评价上,与实际的人体利用情况差异很大。食物消化过程中的p H值、各种消化酶类对食品抗氧化成分的稳定性存在潜在的影响。文章详述了近年来关于食品中多酚、黄酮、类胡萝卜素等主要的抗氧化成分在消化过程中结构变化的最新研究进展,并介绍了其抗氧化能力在消化前后的变化情况,以期为抗氧化成分的活性评价提供理论参考。     

转录组学在储粮害虫研究中的进展

转录组测序技术能将组织或细胞在不同生理条件下的差异基因量化,是探索基因功能和揭示特定生物学过程中分子机理的必要手段。储粮害虫是严重危害储藏粮食的一类害虫,从转录组水平揭示储粮害虫生长发育、关键基因功能、抗药性分子机制等成为研究热点,极大促进了对储粮害虫特别是无参考基因组信息的害虫的研究。因此,本文系统性从生长发育相关基因的挖掘、组织特异性基因、与微生物互作机制、对环境胁迫的响应机制、磷化氢抗性机理和植物精油杀虫机理研究六个方面综述了转录组学在储粮害虫研究中的应用,旨在为储粮害虫的深入研究提供参考,对进一步进行储粮害虫防治技术开发提供理论依据。     

Aflatoxins in spices marketed in Portugal

Seventy-nine prepackaged samples of 12 different types of spice powders (five cardamom, five cayenne pepper, eight chilli, five cloves, seven cumin, five curry powder, five ginger, five mustard, 10 nutmeg, 12 paprika, five saffron and seven white pepper) were selected from supermarkets and ethnic shops in Lisbon (Portugal) for estimation of aflatoxins by immmunoaffinity column clean-up followed by HPLC. Aflatoxin B (AFB) was detected in 34 samples of prepackaged spices (43.0%). All of the cayenne pepper samples were contaminated with levels ranging from 2 to 32 µ g AFB / kg. Three nutmeg samples contained levels ranging from 1 to 5 µ g/kg, three samples had levels ranging from 6 to 20 µ g/kg, and there were two with 54 µ g/kg and 58 µ g/ kg. Paprika contained levels of aflatoxin B₁ ranging from 1 to 20 µ g/kg. Chilli, cumin, curry powder, saffron and white pepper samples had levels ranging from 1 to 5 µ g/kg. Aflatoxins were not detected in cardamom, cloves, ginger and mustard. None of the samples analysed contained aflatoxins B₂, G₁ and G₂.     

黑穗醋栗花色苷研究进展

主要综述了黑穗醋栗花色苷的分布和种类、提取纯化及分析鉴定方法,并对花色苷单体研究进行展望。     

2010年山西省食品中食源性致病菌监测分析

目的 了解山西省食源性致病菌的污染现状.方法 按照2010年度《全国食源性致病菌监测工作手册》进行.结果 1 576份样品中共检出阳性菌株149株,检出率为9.45％,其中单核细胞增生李斯特氏菌、副溶血性弧菌污染比较严重,总检出率为9.50％和8.22％,金黄色葡萄球菌、阪崎肠杆菌和沙门氏菌的总检出率分别为3.02％、1.11％和0.87％.不同类别食品中致病菌的检出率差异较大,生肉中致病菌的检出率高居榜首为49.33％,主要污染菌为沙门氏菌、单核细胞增生李斯特氏菌;沙拉中致病菌的检出率为17.39％,主要污染菌为单核细胞增生李斯特氏菌、金黄色葡萄球菌;生食水产品中致病菌的检出率为16.94％,主要污染菌为单核细胞增生李斯特氏菌、副溶血性孤菌;熟肉制品中致病菌的检出率为9.84％,主要污染菌为单核细胞增生李斯特氏菌、金黄色葡萄球菌、沙门氏菌;中式凉拌菜中致病菌的检出率为8.89％,主要污染菌为金黄色葡萄球菌;鲜榨果汁中致病菌的检出率为6.67％,主要污染菌为金黄色葡萄球菌;鲜冻水产品中致病菌的检出率为5.00％,主要污染菌为副溶血性弧菌;婴幼儿配方粉/米粉/谷粉/豆奶粉中阪崎杆菌的检出率为1.11％.结论 山西省多种食品均存在食源性致病菌不同程度的污染,应加大对散装食品、即食食品和生食水产品的监管.     

中国酵母工业的排头兵

16年弹指一挥间,安琪由一个30多人的科研单位发展成国内乃至亚洲规模最大、品种最多、市场占有率最高的专业化酵母研发生产企业、国家重点高新技术企业、“国家重点科技推广计划酵母技术研究推广中心”、“国家级博士后科研工作站”,“安琪”商标被国家工商总局认定为中国驰名商标,成为名副其实的行业排头兵。2001年,安琪公司上缴国家税金5200多万元。     

Aflatoxins in animal feed in Iran

One hundred and forty-six samples of animal feed (barley, n = 60; wheat bran, n = 22; wheat dry pulp, n = 29; and canola meal, n = 35) were collected in 2011 from Mashhad (Khorasan, Iran). Aflatoxins (AFs) were determined in these samples after immunoaffinity column clean-up by high-performance liquid chromatography (HPLC) with fluorescence detection. Aflatoxin B₁ (AFB₁) contamination was found in 28 samples: in five of the barley samples (8.3%) at a mean level of 0.48 µg·kg^?1, in two wheat bran samples (9.0%) at a mean level of 0.88 µg·kg^?1, in 10 wheat dry pulp samples (34.5%) at a mean level of 0.30 µg·kg^?1 and in 11 canola meal samples (31.4%) at a mean level of 0.92 µg·kg^?1. AFB₁ levels were below the maximum levels of Iran regulations (5 µg·kg^?1) and the EU maximum limit (5 µg·kg^?1).     

Heavy metals in vegetables sold in the local market in Jordan

Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009–0.275 mg kg^?1 wet weight, 0.004–0.060 mg kg^?1, 0.003–0.401 mg kg^?1, 0.105–3.51 mg kg^?1, 0.15–1.15 mg kg^?1, 0.93–14.39 mg kg^?1, 0.044–0.702 mg kg^?1, 0.072–0.289 mg kg^?1 and 2.23–6.65 mg kg^?1, respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.     

南通市2003年食品污染状况监测与分析

为系统准确地了解南通市食品污染物的污染状况和污染水平,从而提出相应的预防方法及改进措施。2003年在严格的质量控制下,按照统一的方法对南通市6县2区共8类食品进行了有关食品污染物的污染状况监测。监测指标为铅、镉、甲胺磷。178份样品中有2份铅超标,均为乳类,合格率为98.88%;动物肾脏、鱼、虾中的镉含量高于CAC标准,合格率分别为27.27%、62.5%、71.4%;蔬菜中甲胺磷的平均检出率为15%,检出率最高的为小白菜(30%)。监测结果提示动物肾脏镉污染严重,应寻找污染源,进一步研究干预措施,从根本上阻断镉在食物链中的迁移。     

中国白酒须关注的"四大问题"

中国白酒业的发展应关注以下“四大问题”：（1）辩证看待“集中度”。中国进入市场经济比较晚，走过的路不长，尚未形成垄断头企业，给中小企业的发展和崛起提供了机遇。今日之“酒业大王”未必是明日之垄断巨头，现实的“大”不代表未来的“大”，但中国白酒走向垄断和集中却是历史的必然；（2）“改制”是“妙药”，但绝非“灵丹”。“改制”是企业发展的一种手段，是过程而非目的，关键是解放生产力，理顺企业经营状况与经营者收益的关系；（3）“通路”后要解决消费者的需求问题。只有把握消费者的需求和变化，才能真正赢得市场，树造白酒品牌应基于人性诉求和自我主张；（4）面对新税制，调整以自救。调整产品结构是核心，必须提高产品档次，才能找到摆脱困境的出路。     

Variation in residual feed intake in Holstein-Friesian dairy heifers in southern Australia

Feed conversion efficiency of dairy cattle is an important component of the profitability of dairying, given that the cost of feed accounts for much of total farm expenses. Residual feed intake (RFI) is a useful measure of feed conversion efficiency, as it can be used to compare individuals with the same or differing levels of production during the period of measurement. If genetic variation exists in RFI among dairy cattle, selection for lower RFI could improve profitability. In this experiment, RFI was defined as the difference between an animal's actual feed intake and its expected feed intake, which was determined by regression of dry matter (DM) intake against mean body weight (BW) and growth rate. Nine hundred and three Holstein-Friesian heifer calves, aged between 5 and 7 mo, were measured for RFI in 3 cohorts of approximately 300 animals. Calves were housed under feedlot style conditions in groups of 15 to 20 for 85 to 95 d and had ad libitum access to a cubed alfalfa hay. Intakes of individual animals were recorded via an electronic feed recording system and BW gain was determined by weighing animals once or twice weekly, over a period of 60 to 70 d. Calves had DM intake (mean ± SD) of 8.3 ± 1.37 kg of DM/d over the measurement period with BW gains of 1.1 ± 0.17 kg/d. In terms of converting feed energy for maintenance and growth, the 10% most efficient calves (lowest RFI) ate 1.7 kg of DM less each day than the 10% least efficient calves (highest RFI) for the same rate of growth. Low-RFI heifers also had a significantly lower rate of intake (g/min) than high-RFI heifers. The heritability estimate of RFI (mean ± SE) was 0.27 (±0.12). These results indicate that substantial genetic variation in RFI exists, and that the magnitude of this variation is large enough to enable this trait to be considered as a candidate trait for future dairy breeding goals. A primary focus of future research should be to ensure that calves that are efficient at converting feed energy for maintenance and growth also become efficient at converting feed energy to milk. Future research will also be necessary to identify the consequences of selection for RFI on other traits (especially fertility and other fitness traits) and if any interactions exist between RFI and feeding level.     

Triazole fungicide degradation in peaches in the field and in model systems

The degradation of five triazole fungicides (cyproconazole, hexaconazole, penconazole, propiconazole, tebuconazole) in peaches was evaluated in field studies to establish whether at the preharvest interval the residue levels were below the legal limit established in Italy. All fungicides, except propiconazole, showed higher residues than the legal limits because of their high stability. In fact, some did not decrease at all (cyproconazole, penconazole, tebuconazole), while others decreased only in part. The increasing weight of the fruit during growth was the main factor leading to an apparent decrease in pesticide levels on a weight for weight basis. The trials on model systems showed that co-distillation and sunlight photodegradation were the main mechanisms leading to a decrease in triazole levels. Although these fungicides are systemic, they did not enter the fruit and all residues were only present in the peel.     

2012年浙江地区蜜饯中食品添加剂情况分析

目的:了解浙江地区蜜饯中食品添加剂的使用情况,为蜜饯中食品添加剂超标情况的风险评估提供技术支持并探讨添加剂超限量的起因和危害,提出合理建议。方法:对浙江地区蜜饯类食品进行随机采样,按照相应的国家标准进行检测和评价。结果:蜜饯合格率96.51%,防腐剂、甜味剂的超标率分别为2.32%和1.16%。结论:浙江地区的蜜饯产品总体情况较好,个别产品存在问题。