基于温湿度时序数据的烟叶烘烤工艺特征分析

为建立基于烘烤环境温湿度时序数据的工艺分析方法,通过在烤房控制仪加装物联网通讯模块,在5类产区采集烘烤过程的温湿度数据1.1万套,分析烘烤时间、湿球温度和工艺拟合曲线,研究不同部位、产区烘烤工艺执行的主要特点。结果表明:基于温湿度时序数据的烘烤工艺分析结果年度间一致,烟叶烘烤总时间的中位值在160~190 h,上部烟叶的变黄期时间较中部烟叶延长5~10 h,变黄后期-干筋后期的湿球温度低0.5~1.0℃。不同产区烘烤各阶段的时间分配、湿球温度调控差异明显,平顶山产区烘烤变黄期时间长,定色期时间短,湿球温度呈上升-下降-上升变化,曲靖产区烘烤变黄期的时间较长、湿球温度较低,南阳、三门峡、恩施产区变黄期和定色期时间相对接近,湿球温度总体呈上升-稳定-上升变化。通过物联网技术采集烘烤过程的温湿度时序数据,可批量分析烘烤时间、湿球温度等工艺执行指标,为烟叶烘烤技术定向优化提供依据。      

基于物联网数据采集技术的河南烟叶烘烤工艺大数据分析

为合理优化烟叶烘烤工艺参数,运用物联网技术采集了河南3个产烟区烘烤温湿度数据,分析烘烤过程的历时和温湿度指标,并结合国内外烘烤工艺进行对比分析。结果表明:(1)中部和上部烟叶烘烤总时长分别集中在6.5～8.0 d和7.0～8.5 d,上部烟叶烘烤过程中湿球温度的波动相对较大。(2)豫西和豫南烟区变黄期、定色期和干筋期时长占烘烤总时长的比例约为40%、35%和25%,豫中烟区变黄期历时明显较长(占烘烤总时长55%左右)。(3)各烟区变黄期、定色期和干筋期的主要稳温阶段分别在40～42℃、43～48℃和61℃以上,变黄后期至干筋期的湿球温度较三段式工艺低1～2℃。(4)相关分析结果显示,变黄后期～定色中期湿球温度调控与烘烤进程密切相关。结合国内外烘烤工艺,可适当延长变黄期38℃和定色期54℃的稳温时间,合理调控变黄后期至定色期的湿球温度,避免大幅度波动,以促进烘烤过程中烟叶内在化学成分的合理转化。     

烤烟温度湿度报警器

我国烟区烧煤的烤房.调制烤烟需人工日夜观察烤房温度和湿度,稍有疏忽,就会影响烤烟质量.为便于掌握烘烤过程中烤房的温度湿度,降低劳动强度,我们设计了一种温度湿度自动报警器.设计烤烟温湿度报警器,对温度的监测既要有升温的监测,也要有降温的监测.我们根据烘烤经验,设计了8个升温监测档,即35℃、37℃、39℃、45℃、49℃、52℃、65℃、72℃(这些温度值可以由用户任意指定).烤房温度一旦达到上述之一的温度,能发出警报声.相应的有8个降温监测档,即34.5℃、36.5℃、     

密集烤房温湿度自控设备应用对比分析

对7种密集烤房温湿度自控设备进行了应用对比试验.结果表明:①基本性能方面,控制点以设备JKM-B、TMC-4为最多;稳定性以设备QZK3000-82、ARC-III、BZK为好;操作难易程度除设备BZK、KX200较难外,其它比较容易;②能耗方面,设备ARC-III、TMC-4能耗最高,设备BZK、SWP-ZN-C3最低,设备QZK3000-82、JKM-B、KX200中等;③温湿度自控方面,7种设备都能够满足烟叶烘烤要求,控制效果较好;④烤后烟叶质量方面,设备QZK3000-82、ARC-III与密集烤房配套能获得较好的烟叶烘烤质量.综合评价,设备ARC-III和QZK3000-82二者的性能表现较为突出,但各自的稳定性和实用性仍有待提高.     

基于物联网的烟叶烘烤温湿度数据采集分析与算法构建

为规范采集和利用烘烤过程烤房干湿球温度数据，运用物联网技术采集烘烤过程烤房干湿球温度数据，利用Python程序建立数据清洗、温湿度曲线识别、烘烤阶段识别、烘烤工艺指标分析算法，并对我国部分烟叶产区2019—2021年的13 493炉次烘烤数据进行分析。结果表明，利用物联网技术采集烤房干湿球温度数据结合算法，可自动提取单座烤房每一炉次烘烤温湿度曲线，并分析烘烤过程的时间管理、湿度管理和异常掉温等烘烤工艺指标。基于算法分析，13个地区（市、州）烟叶产区的烘烤总时长在139.1～188.5 h，变黄期、定色期和干筋期的时长分别为54.5～98.1 h、48.9～69.7 h和34.1～58.7 h，占烘烤总时长的比例分别为33.7%～53.2%、27.5%～41.2%和19.3%～31.7%。烘烤过程变黄前期、变黄中期、变黄后期、定色前期、定色中期、定色后期、干筋后期的湿球温度分别为35.7～36.9℃、35.6～37.4℃、34.5～36.9℃、34.0～36.5℃、34.3～37.1℃、35.2～37.8℃和38.3～41.1℃。基于物联网采集烘烤过程温湿度时序数据并结合算法识别分析，可...     

基于模糊控制的烟叶烘烤系统设计与仿真

通过分析烟叶烘烤过程中温湿度的变化规律,提出一种基于专家经验的烟叶烘烤模糊控制方案.借助Matlab的模糊逻辑工具箱和Simulink仿真工具箱设计模糊控制器并对其进行仿真,结果表明,温度预置范围20-70℃,干湿温度波动最大为±1.5℃,满足工艺要求,该方法正确有效.     

密集烘烤过程中烤烟电特性和主要化学成分变化

为探索利用烟叶的电特性实现烘烤过程中烟叶含水率与化学成分的实时无损快速检测,进而科学调控烘烤温湿度,采用电容仪、电桥仪和常规理化分析方法对烘烤过程中烟叶的电容值、电阻值以及主要化学成分进行了测定。结果表明,烘烤过程中随着烟叶内大分子物质的降解转化和水分的散失,在干球温度38℃至48℃结束时,烟叶电容值呈迅速下降的趋势,48℃之后呈极缓慢下降的趋势;电阻值的变化整体上呈上升趋势,在干球温度36℃至42℃的烟叶变黄期升高趋势较为平缓,且3个温度点烟叶电阻值间差异不显著(P0.05),进入定色期(干球温度42℃之后),烟叶电阻值呈急速骤升的趋势。相关分析表明,烟叶电容值和电阻值与主要化学成分间具有明显的相关性;电容值与含水率间的相关性达到极显著水平,与总糖、总氮、蛋白质、β-胡萝卜素、叶黄质、新黄质和可溶性果胶间相关性达到显著水平;电阻值与含水率和化学成分间存在一定相关性,但没有达到显著水平。     

烤烟烘烤与烟叶香吃味关系研究进展

介绍了烘烤过程中烟叶香气成分的形成和变化规律,综述了烘烤环境温湿度、脱水干燥、气体组分和烘烤设备等烘烤环境条件对烟叶香吃味的影响,并对提高烟叶香吃味的烘烤研究方向进行了展望。     

烤烟生产原理(摘辑)——堆积烘烤

堆积烘烤与一般烘烤的原理很相以,主要的差别是堆积烘烤的烟叶不进行绑竿,而是放在夹内(每夹相当于8—12竿烟)。由于烟叶在夹内很紧靠,就需用鼓风机驱使空气通过密集的烟叶而不是象一般烤房那洋的气流自然上升,两种烘烤系统的温湿度安排应相似,然而堆积烘烤运用空气再循环和淡之较快地干燥,可能用较高的变黄温度(37.4～40.2℃)和较高的湿度。     

预处理技术对冷榨双低菜籽油中脂质伴随物含量的影响

以双低油菜籽为实验材料,研究微波和烘烤预处理对冷榨双低菜籽油中植物甾醇、生育酚和总酚等脂质伴随物含量的影响。研究表明:不同预处理组冷榨菜籽油中均检测到5种植物甾醇,包括胆甾醇、菜籽甾醇、菜油甾醇、豆甾醇和β-谷甾醇;随微波时间的延长,微波预处理组冷榨菜籽油中各甾醇单体及甾醇总量总体呈上升趋势,微波2 min预处理组甾醇总量最高,为982.12 mg/100 g,比对照组高59.85 mg/100 g;烘烤预处理对冷榨菜籽油中植物甾醇总量具有显著影响,180℃烘烤5 min预处理组甾醇总量最低,180℃烘烤10 min预处理组甾醇总量最高;各预处理组冷榨菜籽油中主要含有α-生育酚和γ-生育酚这2种生育酚,油菜籽经微波或烘烤预处理后,冷榨菜籽油中的生育酚单体含量及生育酚总量均显著上升;随着微波或烘烤时间的延长,冷榨菜籽油中的总酚含量不断增加,且微波0～1.5 min组比1.5～2 min组菜籽油中总酚的增长速度快,180℃烘烤0～10 min组总酚的增长速度较10～15 min组快。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

Dioxins and PCBs in ostrich meat and eggs: levels and implications

ABSTRACT

Although consumption of eggs is an essential part of our diet, limited information is available for table eggs other than those laid by hens. The aim of our study was to determine concentrations of polychlorinated dibenzofurans (PCDD/Fs), dioxin-like (DL-) and non-dioxin-like (NDL) polychlorinated biphenyls (PCBs) in ostrich eggs and meat available on the Polish market, in order to obtain baseline information on the current status of these pollutants in comparison to poultry products. Obtained data were compared with the binding EU limits set for chicken eggs and meat. The levels of individual PCDD/Fs and PCBs congeners varied considerably. The percentage share of total WHO toxic equivalency factor (WHO-TEQ) content indicates the dominant role of PCDD/Fs. High concentrations of PCDD/F and DL-PCBs, in the range of 0.85–74.48 pg WHO-TEQ g^?1 fat, were found in ostrich eggs; this exceeds the maximum level permitted for chicken eggs by a factor of up to 15. Eight of the 11 egg samples exceeded the action level for hen eggs. Although the ostrich meat concentrations of PCDD/Fs do not exceed the limit established for poultry muscle (1.75 pg g^?1 fat), average contents of PCDD/Fs exceeded almost four times the levels in chicken and turkey muscle. Human exposure was evaluated and the resulting risk was characterised. Taking into account the low average consumption of ostrich eggs, the resulting exposure to dioxins for the general population can be considered as negligibly low. However, the individuals who frequently consume such eggs may be at risk of elevated exposure. Although ostrich products are not consumed frequently, such data are nevertheless useful for food safety purposes.     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

Phenolic composition and nutraceutical properties of organic and conventional cinnamon and peppermint

Conventional and organic cinnamon and peppermint were investigated for their phenolic profile, anti-proliferative, anti-inflammatory, and antioxidant properties. Accelerated solvent extraction with 75% acetone was used to extract samples. Caffeic acid was the most abundant phenolic acid in peppermint. Catechin, (−)-epigallocatechin gallate, syringic acid, gallic acid, vanillic acid, and p-coumaric acid were also detected in both spices. There was no significant difference between conventional and organic spices in the composition of most individual phenolics. All conventional and organic peppermint and cinnamon extracts exhibited strong anti-proliferative and anti-inflammatory properties. Cinnamon was more efficient in inhibiting IL-1β and COX-2 expression, while peppermint showed better inhibitory effect on IL-6 and MCP-1. This study indicates that cinnamon and peppermint may potentially be used as dietary sources of bioactive phytochemicals for improving health.     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。