Food contamination by hydrocarbons from packaging materials determined by coupled LC-GC

Summary Paraffins from raw extracts of foods and packing materials were isolated by LC and directly transferred to GC, applying concurrent eluent evaporation and a loop-type interface. Paraffins from various packing materials have been characterized: sisal bags, cardboard boxes, plastic films, wax-coated paper and cardboard as well as paraffin coatings. Important food contamination was found for sisal bags, cardboard boxes, and waxcoated paper/cardboard. Contamination by paraffin coatings on cheese was surprisingly small.

---

Verunreinigung von Lebensmitteln mit Kohlenwasserstoffen aus Verpackungsmaterialien und Nachweis mittels gekoppelter LC-GC

Zusammenfassung Die Paraffinfraktion aus rohen Extrakten von Lebensmitteln und Verpackungsmaterialen wurde mittels LC isoliert und durch simultane Abdampfung direkt in den GC transferiert. Typische Paraffinmuster verschiedener Verpackungsmaterialien (Sisalsäcke, Karton, Plastikfolien, Wachspapier und Paraffin) werden charakterisiert. Starke Verunreinigungen der Lebensmittel wurden bei Sisalsäcken, Kartonschachteln, Wachspapieren und Wachskarton gefunden. Die Verunreinigung von Käse durch eine Schicht Paraffin war vergleichbar gering.

     

COLOR CHANGES IN WAXED TURNIPS DURING STORAGE1

Turnip (Brassica campestris, L. var. rapifera) roots were stored unwaxed and waxed with a water-miscible, carnauba-based wax in vented plastic bags or in cardboard produce boxes for 6 weeks. Packaging turnips in plastic bags reduced weight loss during storage more effectively than waxing or storing in boxes. The purple color of the turnips faded regardless of package used; waxing temporarily darkened and intensified the purple color. The white or cream portion of the roots was not affected by waxing but became light tan when roots were stored in boxes. The chroma of the white portion increased during storage regardless of package or wax treatment. These results indicate that the external purple color of the turnip root was unstable during storage and this color loss was independent of weight loss.     

包装方式对西兰花物流保鲜品质的影响

为减少蓄冷剂用量,研究普通聚乙烯(polyethylene,PE)包装袋与微孔PE包装袋协同蓄冷剂的复合保鲜技术对西兰花物流保鲜品质的影响。结果表明:放入4袋蓄冷剂组比不放蓄冷剂组保鲜效果要好,而放入2袋蓄冷剂结合PE包装袋优于4袋蓄冷剂组,2袋蓄冷剂结合PE微孔袋包装的效果最佳。说明PE包装袋特别是PE微孔袋的协同使用可以弥补蓄冷剂用量减少后温度升高带来的保鲜品质下降问题,为解决目前蓄冷剂用量过大导致的成本升高难题提供了新的思路。     

PROLONGING THE SHELF-LIFE OF FRESH GREEN CHILE PEPPERS THROUGH MODIFIED ATMOSPHERE PACKAGING AND LOW TEMPERATURE STORAGE

The postharvest quality of green chile fruit was compared after storage in 3 types of packages at 2 temperatures (24C and 8C). Package types were corrugated cardboard boxes, pressed cardboard trays overwrapped with VF-71 polyethylene, or low-density polyethylene (LDPE) bags. Fruit packaged in boxes or overwrapped trays had 24.8% and 10.1% weight loss, respectively, after 1 week of storage at 24C. Fruit packaged in polyethylene bags lost 0.3% weight and remained green. After 1 week at 8C, the weight losses were 3.8%, 1.8% and 0% for the boxed, overwrapped and bagged treatments, respectively. Postharvest quality was maintained up to 4 weeks when fruit were packaged in LDPE bags and stored at 8C. In a second study, steady state O₂ and CO₂ levels were determined inside the LDPE packages as fruit weight and temperature were varied. Storage temperatures were 24C, 16C and 8C. At 8C, steady state O₂ levels ranged from 12.0 kPa to 0.9 kPa, and CO₂ levels ranged from 2.0 kPa to 4.6 kPa as fruit weight was increased from 120 to 480 g. At 24C and 16C, fruit packaged in 480 g units had slower ripening rates than fruit packaged in smaller units; however, fruit stored at 8C remained green the longest, regardless of fruit weight.     

灰底白板纸与白卡纸阶调再现性能研究

灰底白板纸和白卡纸是两种常用包装材料。为比较这两种包装材料的印刷阶调再现性能的差异,通过对两种纸张8种纸样的表面性能进行测试,然后根据测试结果利用IGT印刷适性仪在一定的印刷条件下进行分组打样,最后结合纸张的表面性能,对比分析两种纸的印刷阶调再现性能及其影响因素。实验结果表明,灰底白板纸和白卡纸的表面性能有较大的差异,并对印刷阶调再现影响较大,白卡纸的阶调再现性要优于灰底白板纸。     

旋转式多工位自动干果包装机的设计

针对现有的干果包装机多为功能单一、占地面积大、对人工依赖程度高等问题,设计一种旋转式多工位自动干果包装机,该机器集干果的定量收集、装袋、热塑封袋、纸袋整齐装箱、自动封箱等功能于一体。该机器结构紧凑,功能齐全,主要包括3个系统,即:旋转式可控定量投料系统,集抓袋、开袋、装袋、封袋于一体的打包系统,装箱、封箱系统。经实验验证,该机器每小时能包装720袋(合360kg)干果,损失率≤2%。     

Food contamination by diisopropylnaphthalenes from cardboard packages

A GC/MS investigation performed on two kinds of foods (rice and 'pasta') and their packages showed the presence of six diisopropylnaphthalene isomers. It has been demonstrated that such compounds, chemical components of carbonless and thermal copy paper, are present in cardboard, usually obtained with recycled paper. This work also demonstrates that diisopropylnaphthalenes can migrate from boxes to foods.     

灰底白板纸与白卡纸阶调再现性和色彩再现性能研究

为比较灰底白板纸和白卡纸这两类包装材料的印刷阶调再现性能和色彩再现性能的差异,通过对两类纸张8种纸样的表面性能（包括光泽度、平滑度、白度和K＆N油墨吸收性）进行测试,根据测试结果利用IGT印刷适性仪在一定的印刷条件下进行分组打样,结合纸张的表面性能,对比分析两种纸张印刷阶调再现性和色彩再现性及其影响因素。实验结果表明,灰底白板纸和白卡纸的表面性能有较大差异,并对印刷阶调再现和色彩再现影响较大,白卡纸的阶调再现性和色彩再现性要优于灰底白板纸。     

QUALITY OF MODIFIED ATMOSPHERE PACKAGED "BARTLETT" PEARS AS INFLUENCED BY TIME AND TYPE OF STORAGE

Commercially mature “Bartlett” pears for this study were obtained from local commercial packing facilities. In the first year, pears were packed in modified atmosphere bags and placed in boxes or packed normally (control) with an individual paper wrap around each pear plus a polyethylene liner in the box. Boxed pears from both types of packaging were stored in regular atmosphere (RA) storage at 1C for 30 or 90 days. In the second year, pears were packed normally and stored in both RA or controlled atmosphere (CA) storage for 45 or 90 days, or packed in modified atmosphere bags and stored in RA at 1C. After 45 days, normally packed pears from both RA and CA were removed from their initial storage, placed in modified atmosphere bags and returned to RA storage for an additional 45 days. Pears stored in modified atmosphere bags were superior in quality to normally packed pears stored only in RA storage and equal in quality to pears stored in CA for periods of 90 days. The quality of pears held in modified atmosphere bags under CA conditions deteriorated after only short periods of time (<45 days). Pears in modified atmosphere bags should be stored only in RA. Little or no quality advantage was evident if use of modified atmosphere bags was delayed regardless of prior storage type.     

Concentrations of migrated mineral oil/polyolefin oligomeric saturated hydrocarbons (MOSH/POSH) in Chinese commercial milk powder products

ABSTRACT

Mineral oil contaminants migrated from food contact materials have raised much concern in the past few decades. However, survey data of the occurrence of mineral oils in foods are only available for a limited variety of foods, which do not include the contaminants in Chinese milk powders. Thus, to conduct an analysis of mineral oils migrated into milk powder products from different packaging materials, 50 Chinese commercial samples (including 38 infant formulas), which were packaged in metal cans, paper containers, paper boxes and aluminium foil-plastic bags, were analysed. Mineral oil saturated hydrocarbons (MOSH), polyolefin oligomeric saturated hydrocarbons (POSH) and aromatic hydrocarbons (MOAH) migrated into those samples were extracted and quantitatively analysed by on-line liquid chromatography coupled with gas chromatography (LC-GC). The results indicated no surface MOAH was detected in any of the samples, while 33 samples contained MOSH/POSH with surface contents of 0.10 ~ 5.09 mg kg^?1. Moreover, the amounts of those MOSH/POSH are closely related to packaging materials, among which the surface contamination values of products in metal cans were the lowest, followed by products in paper containers and boxes, and the values of samples in aluminium foil-plastic bags were the highest. In addition, the surface MOSH/POSH content exhibited a positive correlation with fat content in the samples due to their similar polarities.     

白底涂布白板纸的研制

白底涂布白板纸是一种新型包装装璜包装纸板。该文论述了对白底涂布白板纸的开发研制试产过程。     

精制盐粒度对食盐分装的影响及预防措施

本文通过对全省部分精制盐厂所生产的精制盐粒度进行检测，结合食盐分装实际，归纳出精制盐中粒度太小的盐所占权重过大时，对食盐分装带来的种种不利影响，并提出对精制盐的粒度控制办法，采取预防改进措施，以保证食盐的分装质量，降低成本，真正实现食盐的绿色分装。     

磷化氢对不同包装的片烟穿透能力研究

在用塑料帐幕密封情况下 ,测定了熏蒸空间中和夹板箱、瓦楞纸箱、瓦楞纸箱加塑料内衬 3种包装的片烟内部PH3的浓度 ,比较了目前片烟的 3种主要包装形式对PH3穿透力的影响。结果表明 :在熏蒸空间中 ,熏蒸后 2 4～ 36h ,PH3气体浓度即可达到最大值 ,然后缓慢下降 ;夹板烟及箱装烟内部的PH3气体浓度变化基本与熏蒸空间同步 ;但加塑料内衬的片烟箱内PH3浓度的最大值则出现在施药后 72h ,较熏蒸空间至少滞后 36h ,同时 ,其箱内PH3浓度低于熏蒸空间中PH3浓度 ;散毒期间 ,加内衬的片烟箱内PH3散逸速度比其它两种包装慢     

全自动码垛机的应用

介绍了桥式(旋转式)码垛机、机器人码垛机和高位全自动码垛机的结构特点、工作原理和配置情况。码垛机可以对各种粉状、颗粒状物料进行全自动码垛作业,把已包装的料袋或料箱按一定的排列模式自动编组、自动堆码成所需垛形以便摆放和运输,并配置有定量灌包、金属检测和重量检测功能。     

加碘盐大包装材料试验研究

通过对加碘盐大包装材料的评选与试验,选择出既适合我国国情,又能满足加碘盐生产、储存和运输需要的大包装材料,减少了因破袋等原因造成的碘剂损失,并为加碘盐包装材料方面的标准编制,提供了重要的理论依据.     

Thermal insulation requirements and new cardboard packaging for chilled seafood exports

Three expanded polystyrene (EPS) boxes with different thermal resistance (R-value), a box-in-box type cardboard prototype and commercial EPS boxes were packed with fish using standard industry procedures and subjected to a simulated airfreight temperature regime replicating commercial practice. The Quality Index Method was used to assess the fish quality. The boxes with lower R-values did not have a measurable negative effect on the quality compared to the commercial EPS box. There was also no measurable difference in quality between fish stored in the corners or centre of all the boxes. For another experiment a double fluted cardboard prototype and commercial EPS boxes were filled with ice and subjected to a constant temperature regime to determine their R-value. The second prototype had slightly lower R-values than commercial EPS boxes. However, the double fluted wall structure might limit the foldability and manufacturability and will need to be further investigated.     

橄榄果实的保鲜包装技术研究

本文研究了不同厚度聚乙烯(PE)薄膜袋、不同包装材料及包装方式对檀香橄榄果实保鲜效果的影响。结果表明:包装材料以0.060mm厚的PE袋为好;薄膜打孔的包装方式保鲜效果最好,(8±1)℃保鲜75d,好果率96.40%,失重率0.64%,果实仍鲜绿、饱满,具有新鲜果实的原有风味、颜色和品质;用PE袋包装可以有效地抑制橄榄果实失水,从而延长果实保鲜期。     

Potential for short-term migration of mineral oil hydrocarbons from coated and uncoated food contact paper and board into a fatty food simulant

ABSTRACT

Mineral oil hydrocarbons (MOH) are widely used in the food industry for applications such as printing inks, additives, adhesives, and processing aids for food additives. Recently, the migration of MOH from food contact paper and board into foods has raised public health concerns. In this study, a total of 110 food contact paper and board samples, including baking and cooking paper (23), baking cups (28), food packaging bags (22), lunch boxes (8), party plates (26), and straws (3) were evaluated to quantify the content and short-term migration levels of MOH. The MOH were separated into mineral oil saturated hydrocarbons (MOSH)/polyolefin oligomeric saturated hydrocarbons (POSH) and mineral oil aromatic hydrocarbons (MOAH) via a validated on-line liquid chromatography?gas chromatography?flame ionisation detection (LC–GC–FID) technique. The coating materials of the sample products comprised polyethylene, polypropylene, polyethylene terephthalate, and silicone. The effects of the coating materials on the content and migration of MOH/POSH were evaluated. Quantitative analysis of the MOH in the samples showed that the MOSH/POSH and MOAH content varied widely, ranging from 16 to 5626 mg kg^?1 for MOH, regardless of the coating materials. Short-term migration of MOSH/POSH was observed only in samples with polyolefinic coatings, such as polyethylene and polypropylene, in experiments conducted at 25 °C for 10 min, although the extent of MOAH migration for all samples was at the trace level. The migration of MOSH/POSH was detected within the range of 0.93 to 62.3 μg L^?1 in 22 samples, and the migration of MOAH was detected within the range of 0.80 to 2.6 μg L^?1 in only 4 samples. These results demonstrate that although the short-term migration potential of MOH is generally negligible, the migration of MOSH/POSH into wet fatty foods can be accelerated by polyolefinic coatings, even within a very short time.     

Verunreinigung von Haselnüssen und Schokolade durch Mineralöl aus Jute- und Sisalsäcken

Before spinning, jute and sisal fibres are treated with a batching oil commonly consisting of a raw mineral oil fraction. Such oil is transferred to foods packed into jute or sisal bags, i.e. primarily cocoa beans, hazelnuts, coffee, almonds, oil seeds, and rice. Concentrations in the foods easily exceed 100 mg/kg. Chocolate may be affected several-fold: cocoa beans as well as hazelnuts and almonds may be contaminated.     

相变蓄冷工艺在金枪鱼冷链物流中的应用研究

为研究不同相变蓄冷剂对金枪鱼配送箱内鱼肉品质的影响,本试验分别选取了纯水、质量分数18.8%的Na Cl、46.3%的乙醇以及29%的Ca Cl2溶液制作冰袋,以不加冰袋作为对照,模拟夏季金枪鱼配送箱的配送情况,对箱内温度以及金枪鱼排的中心温度、感官和理化指标进行测定。结果表明,添加相变蓄冷剂能够有效维持配送过程中金枪鱼排品质,且蓄冷材料的相变温度越低,金枪鱼肉品质维持的时间越长。18.8%的Na Cl溶液冰袋能够较好保持鱼肉的品质,可在2 h内将鱼排维持在冻结状态,适合短途配送;46.3%的Ca Cl2溶液冰袋能使鱼排在运输5 h后仍保持冻结状态,中心温度仅-20.74℃,运输末期鱼肉品质接近新鲜鱼肉,红度值高达13.61,硬度及咀嚼性为3.80 N及220.50,明显高于其他试验组,是较好的金枪鱼肉的低温蓄冷材料。