添加剂及储藏温度对糯性粉团抗老化的研究

研究了在不同储藏温度(-18、4、25和37℃)下的糯性粉团,通过分析储藏0-5 d中的水分含量、水分活度、质构特性和热力学特性的变化来研究老化性质,并对食品添加剂对其抗老化作用作了研究。研究表明:(1)在各个储藏温度条件下,食品添加剂的加入可以有效地抑制糯性粉团的老化回生,可使糯性粉团的硬度较小、水分含量较高、水分活度较低、DSC测定的ΔH较小。(2)在-18℃条件下储藏的糯性粉团的老化速率最慢,经过自然解冻后其品质接近于新鲜糯性粉团。当储藏温度位于冰点温度(0℃)以上时,在4℃储藏的糯性粉团的老化速率相比25℃和37℃要快很多,且37℃条件下储藏的糯性粉团的老化速率低于在25℃条件下储藏的糯性粉团。表明糯性粉团最适宜的储藏温度应是-18℃。而当储藏温度位于冰点温度(0℃)以上时,温度越低,糯性粉团的老化回生愈加显著。     

Colour and label evaluation of commercial pasteurised red juices and related drinks

Despite growing demand by consumers for healthy beverages, artificial colours are still widely used. Levels of anthocyanins and artificial colours were determined by HPLC with UV-Vis detection in red orange juices and other red beverages (nectar, juice-based, health, carbonated and sports drinks). The contribution of pigments to the visible colour of the beverage was calculated. Red orange juice samples contained about 34?mg?l^?1 of anthocyanins, which were responsible for about 92% of the visible colour. Red juice-based drinks, containing from 0% to 30% of red orange, berry, grape or pomegranate juices, had low levels of anthocyanins (about 7?mg?l^?1) and high levels of E129 (about 32?mg?l^?1), which were responsible for about 90.7% of the colour of these beverages. Red health drinks, enriched with vitamins and polyphenols, contained from 3% to 50% of red fruit juices. Also in this case the E129 levels were higher (about 22?mg?l^?1) than anthocyanins (about 9?mg?l^?1), and were responsible for the colour of the beverages (76.1%). High levels of artificial colours were found in red orange carbonated drinks, but in comparable amounts with those found in the other beverage samples, while anthocyanins were only present in trace amounts. Although all of the beverages claimed to contain red fruits on the labels, no correlation was found between the level of anthocyanins and the declared percentage of red fruits. These labels generally conformed with the requirements of the law, but food product labels can often be misleading to consumers about the real characteristics of the product.     

百香果汁褐变抑制剂的试验研究

为比较不同褐变抑制剂对热带水果百香果汁褐变抑制的效果,以百香果为研究对象,选取Vb-Na、植酸、NaC1、CaCl2、抗坏血酸及异抗坏血酸钠作为褐变抑制剂,分别进行单因素和正交抗褐变试验.单因素试验中,抗褐变效果依次为:Vb-Na＞植酸＞抗坏血酸＞异抗坏血酸钠,而NaCl及CaCl2对百香果汁基本不起抗褐变作用.正交试...     

当前我国食品添加剂的现状及监管建议

近年来,随着经济发展及生活水平的提高,食品安全问题越来越受到广泛关注。而食品安全问题中,有关食品添加剂的安全这几年更是颇受关注,许多是由于添加工业产品而被人们误认为食品添加剂,我们应该正确认识食品添加剂。本文分析了当前我国食品添加剂使用中存在的问题,并对食品添加剂的安全监管提出相关建议。     

2017~2018年常熟市饮料中6种食品添加剂 监测分析

目的 了解常熟市市场上饮料中苯甲酸、山梨酸、糖精钠、安赛蜜、甜蜜素和咖啡因6种食品添加剂的含量情况。方法 2017~2018年采集常熟市各大超市、农贸市场、街头饮料铺采集各类饮料, 采用高效液相色谱-串联质谱法进行检测。结果 苯甲酸在碳酸、果蔬类、茶类、咖啡类、蛋白饮料中的检出率分别为33.3%、10%、10%、6.7%、20%, 其中, 碳酸饮料超标率为3.3%, 蛋白饮料超标率为6.7%; 山梨酸在碳酸、果蔬类、茶类、咖啡类、蛋白饮料中的检出率分别为70%、18%、16.7%、10%、33.3%, 其中, 碳酸饮料超标率为10%, 蛋白饮料超标率为3.3%; 糖精钠在碳酸、果蔬类、茶类、咖啡类、蛋白类饮料中均未检出; 安赛蜜在碳酸、果蔬类、茶类、咖啡类、蛋白饮料中的检出率分别为91.7%、10%、0%、20%、40%, 其中, 碳酸饮料超标率为20%; 甜蜜素在碳酸、果蔬类、茶类、咖啡类、蛋白饮料中的检出率分别为10%、0%、10%、16.7%、6.7%; 咖啡因在碳酸、果蔬类、茶类、咖啡类、蛋白饮料中的检出率分别为58.3%、0%、40%、100%、0%, 其中, 碳酸饮料超标率为25%。结论 常熟市市场上销售的饮料还存在一定的安全风险, 需要监管部门加大监管力度, 保证食品安全, 保障老百姓身体健康。     

甜高粱青贮饲料中乳酸菌最佳添加剂量的探讨

研究自制复合乳酸菌制剂对甜高粱秸秆青贮品质的影响,以探讨自制复合乳酸菌制剂对甜高粱秸秆青贮的最佳添加剂量。以甜高粱秸秆为材料,分别接种0.5mL/kg、1.0mL/kg、1.5mL/kg、2.0mL/kg、2.5mL/kg的自制菌剂和一定比例的台湾、美国商品青贮 菌剂,并以不加菌剂为空白对照（CK）进行青贮,青贮后检测分析评价。添加自制菌剂后,乳酸含量明显提高（P＜0.05）,中性洗涤纤 维含量显著降低（P＜0.05）,氨基酸态氮/总氮含量下降。添加量为1.5mL/kg时,乳酸含量最高,较对照高了177.15%,较美国、台湾分 别高出29.90%、31.18%;粗蛋白含量最高,比对照高了25.61%,比美国、台湾分别高出13.51%、8.91%;同时,1.5mL/kg处理组总糖含量 较美国、台湾高出14.01%、6.81%。经综合评价,自制乳酸菌剂可提高甜高梁青贮发酵品质,最佳添加量为1.5mL/kg。     

欧盟、美国和日本食品添加剂技术贸易措施对我国酒类产品出口的影响

对欧盟、美国、日本和我国部分甜味剂、香料的相关法规、标准进行了分析,比较研究其在酒类产品中的添加种类及限量。同时,结合我国酒类产品出口的扣留事件,为酒类企业在关于甜味剂使用方面提出了建议。     

二氢猕猴桃内酯的合成及作为卷烟香料的应用

经过三步反应即环化反应、Darzen反应和氧化反应,柠檬醛4转化成重要的挥发性香料组分二氢猕猴桃内酯1(9-氧杂-1,5,5-三甲基-双环[4,3,0]壬-6-烯-8-酮),总产率为33.5%。该合成方法的关键步骤是,β-环柠檬醛3与溴乙酸乙酯经过Darzen反应生成β-环高柠檬醛2。合成得到的二氢猕猴桃内酯1经mp、IR、MS、1HNMR和元素分析鉴定。结果表明,化合物1应用于烤烟型卷烟香料中具有增加卷烟香气,丰满卷烟香味和降低刺激的作用。      

电喷雾-离子迁移谱法快速筛查保健品和中成药中5种违禁化学药物

目的建立电喷雾-离子迁移谱(electrospray ionization-ion mobility spectrometry,ESI-IMS)技术快速筛查改善睡眠类保健食品和中成药中非法添加地西泮、咪达唑仑、硝西泮、阿普唑仑、巴比妥等5种化学药物的分析方法。方法样品用乙腈超声提取,90%乙腈水溶液稀释后ESI-IMS直接测定。在正离子模式下检测地西泮和咪达唑仑,在负离子模式下检测硝西泮、阿普唑仑、巴比妥,基质外标法定量。结果 5种化合物在各自浓度范围内线性关系良好,相关系数均大于0.99。地西泮、咪达唑仑、巴比妥、硝西泮、阿普唑仑的检出限分别为0.20、0.50、2.00、8.00、8.00mg/L,平均回收率为78.7%~113.8%,相对标准偏差(RSD,n=6)小于10%,与液相色谱-串联质谱(1iquid chromatography-tandem mass spectrometryLC-MS/MS)检测结果一致。结论本方法快速准确,可实际应用于改善睡眠类健康产品中非法添加地西泮、咪达唑仑、硝西泮、阿普唑仑、巴比妥等5种违禁药物的筛查。     

Risk-based approach to developing a national residue sampling plan for testing under European Union regulation for veterinary medicinal products and coccidiostat feed additives in domestic animal production

A ranking system for veterinary medicinal products and coccidiostat feed additives has been developed as a tool to be applied in a risk-based approach to the residue testing programme for foods of animal origin in the Irish National Residue Control Plan (NRCP). Three characteristics of substances that may occur as residues in food are included in the developed risk ranking system: Potency, as measured by the acceptable daily intake assigned by the European Medicines Agency Committee for Medicinal Products for Veterinary Use, to each substance; Usage, as measured by the three factors of Number of Doses, use on Individual animals or for Group treatment, and Withdrawal Period; and Residue Occurrence, as measured by the number of Non-Compliant Samples in the NRCP. For both Number of Doses and Non-Compliant Samples, data for the 5-year period 2008–12 have been used. The risk ranking system for substances was developed for beef cattle, sheep and goats, pigs, chickens and dairy cattle using a scoring system applied to the various parameters described above to give an overall score based on the following equation: Potency × Usage (Number of Doses + Individual/Group Use + Withdrawal Period) × Residue Occurrence. Applying this risk ranking system, the following substances are ranked very highly: antimicrobials such as amoxicillin (for all species except pigs), marbofloxacillin (for beef cattle), oxytetracycline (for all species except chickens), sulfadiazine with trimethoprim (for pigs and chickens) and tilmicosin (for chickens); antiparasitic drugs, such as the benzimidazoles triclabendazole (for beef and dairy cattle), fenbendazole/oxfendazole (for sheep/goats and dairy cattle) and albendazole (for dairy cattle), the avermectin ivermectin (for beef cattle), and anti-fluke drugs closantel and rafoxanide (for sheep/goats); the anticoccidials monensin, narasin, nicarbazin and toltrazuril (for chickens). The risk ranking system described is a relatively simple system designed to provide a reliable basis for selecting the veterinary medicinal products and coccidiostat feed additives that might be prioritised for residue testing.