Crack Development in Individually Quick Frozen Cut and Peel Carrots

ABSTRACT:  Crack development during freezing (CDF) is one of the major challenges in individually quick frozen (IQF) cut and peel carrot processing. The effects of processing and freezer storage on crack development were examined on the cut and peel carrot variety, Sugarsnax. Carrot samples were removed from the major processing steps, the trans-slicer, the shaper, the blancher, and the dryer, and examined for crack development by measuring percentage cracked, crack morphology, total soluble solids, moisture levels, and membrane injury index immediately after processing. These parameters were also examined following 20 wk of standard freezer storage for cut and peels. Approximately 2% of nonprocessed carrots were cracked compared to 45% of carrots after the initial trans-slicing stage. As the processing continued, cracking decreased due to the removal of the outer epidermis to 16% of the finished product. This suggests that CDF was initiated at the 1st processing stage. Crack width and depth were 2.3 and 2.6 mm, respectively, at the trans-slicer stage and decreased to 1.1 and 1.8 mm at the end of the line. It was found that CDF was further exacerbated by freezer storage due to inefficient water removal at the dryer stage. Crack width and depth increased to 1.5 and 3.0 mm after 20 wk for freezer storage. Root size also played a role in CDF, suggesting that larger pieces are more susceptible to crack development. Total soluble solid concentrations did not play a role in crack formation during cut and peel processing.     

人才测评软件设计——之瞬时记忆力测试子系统

系统地介绍了一个传统人才测评模型的计算机实现方案以及系统优化的途径。并通过与传统测评方式的比较 ,进一步阐明了新系统的灵活性、扩展性、适应性。文末分析了该人才测评子系统在幼儿启智方面的应用。     

High‐Pressure Thermal Sterilization: Food Safety and Food Quality of Baby Food Puree

The benefits that high‐pressure thermal sterilization offers as an emerging technology could be used to produce a better overall food quality. Due to shorter dwell times and lower thermal load applied to the product in comparison to the thermal retorting, lower numbers and quantities of unwanted food processing contaminants (FPCs), for example, furan, acrylamide, HMF, and MCPD‐esters could be formed. Two spore strains were used to test the technique; Geobacillus stearothermophilus and Bacillus amyloliquefaciens, over the temperature range 90 to 121 °C at 600 MPa. The treatments were carried out in baby food puree and ACES‐buffer. The treatments at 90 and 105 °C showed that G. stearothermophilus is more pressure‐sensitive than B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food. The amounts of furan could be reduced between 81% to 96% in comparison to retorting for the tested temperature pressure combination even at sterilization conditions of F₀‐value in 7 min.     

Monitoring survey of patulin in a variety of fruit-based products using a sensitive UHPLC–MS/MS analytical procedure

The mycotoxin patulin is known to be the predominant natural contaminant of apples, apple-based products and a variety of other fruits. Because of its high incidence and harmful health effects, patulin is included with mycotoxins, which are strictly monitored. In this study, a sensitive and reliable ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) method was developed and validated for determination of patulin in a variety of fruit matrices. A combination of the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) procedure along with a solid phase extraction (SPE) clean-up strategy enabled an effective removal of sample matrix and pre-concentration of patulin. This resulted in low limits of quantification ranging from 1 to 2.5 μg/kg, depending on fruit type. In our study, quantification of patulin was based on a stable isotope dilution assay (SIDA) using ¹³C₇-patulin as the internal standard. Data showed that the procedure described, in combination with neat solvent internal calibration, can be used for accurate quantification of patulin regardless the type of fruit. Although the SIDA method allowed omission of matrix-matched calibration, matrix-effects were estimated in order to assess suppression of the patulin signal caused by a variety of fruit samples. The method was fully validated for apples, apple baby food, apple juice, peaches, strawberries and blueberries. The recovery values were in the range from 92 to 109%. Repeatability of the method was below 10% for all tested matrices. The method was applied to the monitoring of patulin in 135 samples of fresh fruits and fruit products and can also be used as an efficient tool for routine monitoring of this contaminant in a variety of fruit-based foods.     

Multiclass method for fast determination of veterinary drug residues in baby food by ultra-high-performance liquid chromatography–tandem mass spectrometry

A simple and rapid multiresidue method for the determination of different veterinary drug residues in meat-based baby food (MBF) and powdered milk-based infant formulae (PMIF) has been developed. The method involves an extraction procedure based on buffered QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology, without any further clean-up step, followed by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method has been validated in two baby food matrices (MBF and PMIF) at three different concentration levels, obtaining suitable recoveries and precision (inter and intra-day precision) values. Quantification was carried out using matrix-matched standard calibration. Furthermore, the decision limit (CCα) and the decision capability (CCβ) were evaluated, ranging from 0.5 to 16.2 μg/kg and from 1.2 to 22.4 μg/kg, respectively. Finally, the method was applied to the analysis of several kinds of baby food samples and traces of some veterinary drugs were detected.     

童车测试系统中的模块化设计

为了对各种童车的性能指标按国家标准进行检测，研制了多功能加载试验机。采用模块化的设计思想，将试验机划分为加载模块、机架模块、升降模块与翻转模块，并对各功能模块进行设计，提出了电气的模块化的设计思想并应用于实践。最后对基于模块化的童车多功能加载试验机进行实验验证。实验表明该系统能很好的进行多种功能的加载，控制精度较高，加载稳定，满足了测试标准要求的童车测试加载要求，为童车的精确检测提供了加载手段。     

Study on the effect of grain storage and processing on deltamethrin residues in post-harvest treated wheat with regard to baby-food safety requirements

The effects of storage intervals and of milling procedures on dissipation of deltamethrin residues in post-harvest treated wheat grain were studied with the aim to obtain scientific data on compliance of the processed products with the safety requirements concerning baby foods. The insecticide formulation was applied on stored wheat at a recommended rate of active ingredient of 0.5 mg kg^-1 and at a higher rate of 4 mg kg^-1, performing the highest protective effect. The dissipation of residues and their distribution in different fractions of the milled grain were studied after various storage intervals, from 7 to 270 days after treatment. Eight fractions—bran, semolina, three types of groats, and three types of flour—were collected after milling of grain and analysed for determination of pesticide residues. The residues were determined by gas chromatography characterized by the limit of determination of 0.005 mg kg^-1, low enough for enforcement of the maximum residue level of 0.01 mg kg^-1 established by the European Commission Directive for any pesticide in cereal-based foods. Deltamethrin applied post-harvest on wheat as grain protectant was distinguished by low rate of degradation on the grain under practical storage conditions. One hundred and eighty days after treatment at an application rate of 0.5 mg kg^-1, the residues were between 0.03 and 0.2 mg kg^-1 in the various types of flour. Two hundred and seventy days after treatment at a rate of 4 mg kg^-1, the residues in the flour were in the range of 0.4-1.5 mg kg^-1.     

婴幼儿护理品市场回顾

论述了婴幼儿护理品市场的现状，就婴幼儿护理品原料的选择进行了探讨。表明婴幼儿护理品中天然和具有稳定性的化学物质仍然是原料发展的主流，生态型和天然绿色产品是婴幼儿护理品的发展趋势。同时对婴幼儿护理品中防腐剂的使用以及科学改进提出了建议。     

婴幼儿健齿食品生产工艺的研究

以面粉、食盐、酵母、脱脂奶粉、碳酸钙等为原料,经过和面、压片、成形、醒发、烘烤等工艺,加工成了一种适合婴幼儿长牙或换牙期间使用的健齿食品.以感观评价值、硬度值为指标,通过正交试验,确定了最佳生产工艺,并对产品的主要质量指标进行了测定.     

子嗣观的物化与外显——婴戏纹样的吉祥寓意表达

婴戏纹是中国传统吉祥纹样中的经典,它采用托物兴意的手法,反映出人们对多子多福的向往。本文从历史学和社会学等角度对婴戏纹进行了较为细致的考证。强调了婴戏纹作为纹饰与绘画和装饰艺术的紧密关联,同时也对纹样与其所处历史环境、宗教信仰的关系展开思考,文章还进一步从中国传统的家族子嗣文化维度对其展开思考。