Efficient and robust multi-objective optimization of food processing: A novel approach with application to thermal sterilization

The optimization of thermal processing of foods is a topic which has received great attention during the last decades. The majority of the authors have considered the use of single-objective (criteria) for the optimization. However, the simultaneous optimization of several objectives is much more realistic and desirable, but the associated non-linear programming problems can be very challenging to solve. Here, we describe an efficient and robust multi-criteria optimization method which can be successfully applied to large dynamic systems, like those arising from the modelling of thermal processing of foods. Further, their capabilities for better design and operation of these processes will be highlighted with selected case studies, where the generated Pareto solutions will be analysed. Finally, we will also illustrate their advantages over other recently proposed strategies.     

Framework for implementing traceability system in the bulk grain supply chain

Implementation of a traceability system in the bulk grain supply chain is a complex task. Grain lots are often commingled to meet buyer specifications and the lot-identity is not maintained. In this paper, a systems approach is used to develop methods for implementing bulk grain supply chain traceability in the United States, that includes both internal and chain traceability. First, the usage requirements of a traceability system are defined for all the actors in the supply chain. Second, a model is developed for implementing internal traceability system for a grain elevator that handles specialty grain. Then, we develop a model for information exchange between the supply chain actors. The model shows what grain lot information must be recorded and then passed on to the next actor. A sequence diagram is developed to show the information exchange in the grain supply chain when a user requests additional information about a suspect product. Finally, we discuss some suitable technologies to enable this information exchange. A few sample XML documents are shown for the transfer and sharing of information in the grain supply chain.     

我国散粮集装箱装卸技术研究进展

总结了目前国内外港口、粮库、大中型粮食企业和小型粮食企业散粮集装箱运输中的装卸设备及相关技术,分析了我国集装箱散粮装卸过程中仍需解决的问题,比如专用集装箱研发、装卸机械缺乏、相关标准缺乏等,探讨了我国散粮集装箱运输装卸技术的发展方向,以期促进集装箱散粮运输装卸技术的进一步完善提升.     

Pathways to increase consumer trust in meat as a safe and wholesome food

This paper focuses on the effect of information about meat safety and wholesomeness on consumer trust based on several studies with data collected in Belgium. The research is grounded in the observation that despite the abundant rise of information through labelling, traceability systems and quality assurance schemes, the effect on consumer trust in meat as a safe and wholesome product is only limited. The overload and complexity of information on food products results in misunderstanding and misinterpretation. Functional traceability attributes such as organisational efficiency and chain monitoring are considered to be highly important but not as a basis for market segmentation. However, process traceability attributes such as origin and production method are of interest for particular market segments as a response to meat quality concerns. Quality assurance schemes and associated labels have a poor impact on consumers' perception. It is argued that the high interest of retailers in such schemes is driven by procurement management efficiency rather than safety or overall quality. Future research could concentrate on the distribution of costs and benefits associated with meat quality initiatives among the chain participants.     

粮食脂肪酸值测定影响因素分析及优化

影响粮食脂肪酸值测定结果的因素很多,对振荡器振幅、实验用水、指示剂、标准滴定溶液四个方面进行研究,探讨粮食脂肪酸值测定的优化方法.研究结果表明,振荡器振幅对测定结果存在显著影响,用三级水、百里香酚蓝指示剂、水溶剂氢氧化钾标准滴定溶液代替现行方法中的不含CO2的蒸馏水、酚酞指示剂、95％乙醇溶剂氢氧化钾标准滴定溶液对测定...     

Orientation of rusty grain beetles,Cryptolestes ferrugineus (Coleoptera: Laemophloeidae), to semiochemicals in field and laboratory experiments

Cryptolestes ferrugineus is a common beetle pest of stored grain for which techniques to monitor dispersing beetles are limited. Early research found several male-produced aggregation pheromones, but there has been little related work since that time. This paper reports experiments on orientation of C. ferrugineus in response to synthetic pheromones and other semiochemicals via flight and walking. Field trapping studies showed that flying beetles were caught on the western sides of grain bins in Kansas compared to the other three cardinal directions. Work with synthetic formulations of the two male-produced aggregation pheromones found that flying beetles were attracted to traps with the pheromone and wheat compared to traps with wheat only. Walking bioassays in the laboratory determined that either of the two aggregation pheromones, known as Cucujolide I and Cucujolide II, were attractive whether deployed singly or in combination. Laboratory bioassays showed that volatiles from grains, other grain-based materials and two commercial food attractants used in traps were attractive to C. ferrugineus. Further laboratory assays demonstrated that C. ferrugineus would orient to synthetic pheromones of three other beetle species and one moth species, all common pests of stored products. These new data on semiochemicals for C. ferrugineus suggest future work that could be done toward developing new tools for detecting and monitoring this serious pest.     

粮食仓储企业粉尘爆炸风险分析及防控措施研究

在论述粮食粉尘特性、爆炸特点的基础上,分析了引发粮食粉尘爆炸的工艺设计因素和生产管理因素,并进行了典型事故案例分析.依据粮食仓储企业粉尘爆炸的风险和粉尘防爆相关标准,编制了粮食仓储企业粉尘防爆安全检查表,由此可以确定粮食仓储企业粉尘爆炸的风险点和安全等级.最后提出了粮食仓储企业粉尘爆炸防控措施,为粮食仓储企业粉尘防爆提...     

QuEChERS净化-超高效液相色谱-串联质谱法测定粮食制品中4种真菌毒素

目的建立超高效液相色谱-串联三重四级杆质谱(UPLC-MS/MS)测定面包、馒头和饼干等粮食制品中4种真菌毒素的方法。方法样品用乙腈-水(84∶16,V/V)超声提取,经QuEChERS方法净化,采用BDS HYPERSIL C18色谱柱(4.6 mm×100 mm,2.4μm)进行分离,以甲醇-乙酸铵缓冲液为流动相梯度洗脱,流速为300μl/min,在电喷雾负离子化模式(ESI-)和多反应监测模式(MRM)下进行检测,采用基质外标法定量。并对方法的检出限、定量限、准确度和精密度进行评价,用建立的方法对60份市售粮食制品中的4种真菌毒素进行检测。结果在优化条件下,4种真菌毒素在各自的线性范围内线性关系良好,相关系数(r)均不低于0.999,回收率在81.8%~98.2%之间,相对标准偏差在5.6%~9.3%之间。60份市售粮食制品中均检出脱氧雪腐镰刀菌烯醇,含量为15.2~960μg/kg,其余3种真菌毒素均未检出。结论该方法与国家标准方法和国家食品安全风险监测方法比较,具有操作简单、成本低的优点,且速度快、灵敏度高、重现性好,完善了我国食品安全风险监测的方法。     

A fundamental approach and its experimental validation to simulate density as a function of moisture content during drying processes

Although several empirical models are available in the literature to predict density in solid matrices, only a very limited number of theoretical models have been reported. So far, no model considered the possible variation in the initial air volume existing at the beginning of the drying process. In this contribution, a theoretical model to predict bulk density of dried materials was built by considering two mechanisms that might occur during drying processes. These mechanisms are represented by collapse and shrinkage functions. The predictions obtained by this theoretical model were extensively validated with experimental data published by several independent groups for different food products dried with different technologies. In all these cases, the model gave excellent agreement with the experimental data regardless the topology of the curve bulk density versus moisture content. The model was also compared with other published models. The result of this comparison revealed that the errors resulting from the predictions obtained by the present model are among the smallest. Shrinkage and collapse functions were used to analyze the mechanisms by which bulk density varies during air-drying and freeze-drying. The model showed that both shrinkage and collapse phenomena are dramatically involved during air-drying. However, in the case of freeze-drying, no collapse is observed and only partial shrinkage is taking place. Hence, the present model can be used as a tool to predict the bulk density with excellent accuracy, to understand the dynamic mechanisms involved during drying. Moreover, this model can be incorporated to other models involving the variation of density as a function of moisture.     

高效液相色谱法测定粮食及其制品中赭曲霉毒素A提取条件的优化

目的 优化高效液相色谱法测定粮食及其制品中赭曲霉毒素A(ochratoxin A, OTA)的提取条件。 方法 样品通过乙腈-水(60:40, V:V)提取, 高速均质2 min或振荡提取20 min, 采用赭曲霉毒素A免疫亲和柱浓缩净化、高效液相色谱-荧光检测器定量检测。结果 选用OTA自然污染的粮食样品优化方法更符合实际检测。60%乙腈-水的提取效率优于80%的甲醇-水, 且振荡提取20 min, 一次提取即可提取样品中99%以上的OTA。4种粮食及其制品中OTA在0.2~50 ?g/kg范围内线性关系良好, 相关系数为r2=0.9997。加标回收率为80.7%~108.0%, 变异系数为1.6%~7.5%, 检出限为0.06 μg/kg, 定量限为0.2 μg/kg。采用此方法参加比利时国际能力验证, |Z|<2, 结果满意。同时, 基于本方法组织的国际实验室环形验证中, 粮食及其制品中OTA测定值的统计结果符合《食品法典委员会程序手册》(第二十版)中关于联合验证中HorRat在2之内的规定。 结论 优化后的方法灵敏度高、准确性好, 适合粮食及其制品中赭曲霉毒素A的精准测定。     

Biosecurity Measures to Control Salmonella and Other Infectious Agents in Pig Farms: A Review

Salmonellosis is the 2nd most common cause of human bacterial food poisoning and can be acquired from meat or eggs, either via direct consumption or cross‐contamination in the kitchen. The European Commission has set the criteria to control Salmonella infections within the poultry sector and it is proposed that the swine sector should follow. Pork is considered, after eggs, the major source of infection in humans in the EU, with Salmonella typhimurium, including monophasic strains, being frequently implicated. Good control measures at the farm level are likely to correspond with lower prevalence of Salmonella infection and, subsequently, a reduction of cross‐contamination of carcasses processed at the slaughterhouse and a reduction in human salmonellosis. This review focuses on biosecurity measures in pig farms that can help to control important pig diseases at the same time as reducing the within‐herd prevalence of Salmonella. This information is likely to provide an economic incentive for farmers to apply improved general standards of farm biosecurity and hygiene management that would have a positive impact in food safety.     

A novel approach to authenticity control of whole grain durum wheat (Triticum durum Desf.) flour and pasta,based on analysis of alkylresorcinol composition

Since durum wheat is ∼20% more expensive than common wheat and considered of superior quality for the manufacture of pasta products, efficient methods for the detection of accidental or intentional admixtures of common wheat to durum wheat products are required. This paper describes a novel approach for the detection and quantification of whole grain common wheat adulteration in whole grain durum flour and dried pasta. We found that differences in the C17:0 to C21:0 alkylresorcinol homologue ratios between the two cereal species may serve as a suitable tool for whole grain durum product authentification. To detect and estimate adulteration, the C17:0/C21:0 ratios of flour and pasta admixtures with added whole grain flour of common wheat were analysed. A linear relationship between C17:0/C21:0 ratios and level of admixture in pasta samples showed that adulteration can be estimated within the range of 5–100% of admixture. Furthermore, di- and triunsaturated as well as oxygenated alk(en)ylresorcinols are reported to occur in Triticum durum Desf. for the first time.     

Fecundity and ability of the parasitoid Lariophagus distinguendus (Hymenoptera: Pteromalidae) to find larvae of the granary weevil Sitophilus granarius (Coleoptera: Curculionidae) in bulk grain

Fecundity and host finding behavior in the storage environment were examined for the parasitoid Lariophagus distinguendus (Förster), a potential agent for biological control of stored-product pest beetles. Larvae of the granary weevil, Sitophilus granarius (L.), in wheat were used as hosts. The fecundity varied considerably among strains of different geographical origin, from 1.3±2.4 to 92.5±23.6 offspring per female parasitoid. Host finding ability was examined in a small acrylic cylinder (about 42 kg wheat), a silo-bin (20.5 t wheat grain), and the flat storage grain bin in a commercial facility (3000 t rye). Experiments in the cylinder and the silo-bin revealed that the number of hosts found by the parasitoids decreases with increasing depth. Moreover, parasitoids were more likely to find hosts in the cylinder than under field storage conditions in a silo-bin. This indicates that the density of parasitoids per unit volume of the grain might be an important factor in determining how deep they penetrate a grain layer. In the silo-bin and the commercial grain store, parasitoids were able to find and parasitize hosts located up to 4 m vertically and horizontally from the release point. The significance of these results with respect to the suitability of L. distinguendus for biological control of the granary weevil is discussed.     

Dietary exposure assessment of Danish consumers to dithiocarbamate residues in food: A comparison of the deterministic and probabilistic approach

Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from the nationwide dietary survey conducted in 2000–02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998–2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using the probabilistic approach, the daily acute intakes at the 99.9% percentile for adults and children were 11.2 and 28.2 μg kg^?1 body weight day^?1, representing 5.6% and 14.1% of the ARfD for maneb, respectively. When comparing the point estimate approach with the probabilistic approach, the outcome of the point estimate calculations was generally higher or comparable with the outcome of the probabilistic approach at the 99.9 percentile (consumers only). The chronic exposures for adults and children were 0.35 and 0.76 μg kg^?1 body weight day^?1 at the 99.9 percentile, representing 0.7% and 1.5%, respectively, of the acceptable daily intake for mancozeb and maneb at 50 μg kg^?1 body weight.     

A Weibull model to describe antimicrobial kinetics of oregano and lemongrass essential oils against Salmonella Enteritidis in ground beef during refrigerated storage

The antimicrobial effect of oregano (Origanum vulgare L.) and lemongrass (Cymbopogon citratus (DC.) Stapf.) essential oils (EOs) against Salmonella enterica serotype Enteritidis in in vitro experiments, and inoculated in ground bovine meat during refrigerated storage (4 ± 2 °C) for 6 days was evaluated. The Weibull model was tested to fit survival/inactivation bacterial curves (estimating of p and δ parameters). The minimum inhibitory concentration (MIC) value for both EOs on S. Enteritidis was 3.90 μl/ml. The EO concentrations applied in the ground beef were 3.90, 7.80 and 15.60 μl/g, based on MIC levels and possible activity reduction by food constituents. Both evaluated EOs in all tested levels, showed antimicrobial effects, with microbial populations reducing (p ≤ 0.05) along time storage. Evaluating fit-quality parameters (RSS and RSE) Weibull models are able to describe the inactivation curves of EOs against S. Enteritidis. The application of EOs in processed meats can be used to control pathogens during refrigerated shelf-life.