含碳成型纸降低卷烟烟气有害成分的研究

研究一种新型含碳成型纸对降低卷烟烟气有害成分的影响。结果表明,对两种不同牌号卷烟,使用含碳成型纸可明显降低卷烟烟气总粒相物含量、焦油含量、CO含量,卷烟烟气的烟碱含量亦有所下降。同时该成型纸与醋酸纤维丝束卷制工艺简单,烟支改装不污染机器,成本低。     

不同型号吸烟机对卷烟主流烟气释放量的影响

为了比较不同型号吸烟机对卷烟主流烟气释放量检测结果的差异,分别使用RM200A和RM20H转盘式吸烟机在同一实验条件下对4个样品进行检测,并对卷烟主流烟气释放量(总粒相物、水分、焦油、烟气烟碱、烟气一氧化碳)及抽吸口数进行差异性分析.结果表明:RM200A所测样品结果的相对标准偏差小于RM20H所测结果;RM200A测定卷烟样品的CO低于RM20H所测结果,两者有显著性差异;盒标值7 mg以上样品,RM200A所测水份低、烟碱高.     

主成分分析-支持向量机在卷烟主流烟气分析中的应用

采用主成分分析进行样本集特征的提取,结合支持向量机建立回归模型,并对成品卷烟主流烟气中的总粒相物、焦油量和烟气烟碱含量进行定量预测。结果表明:总粒相物、焦油和烟气烟碱的预测均方差分别为0.61,0.47和0.04,与模型相比分别下降了30.73%,26.12%和8.15%,体现了更高的预测准确度。     

卷烟主流烟气中一氧化碳的研究

CO是卷烟的有害成分之一。通过测定国内44种卷烟烟气成分,确定烟气中CO产生量与卷烟烟气中焦油、总粒相物(TPM)的关系;同时通过外加助燃剂考察了燃烧状态对烟气中CO的影响。气相色谱法测定卷烟烟气中的水分和非散射红外法测定卷烟烟气中的CO,实验数据采用回归分析。结果表明:高焦油、高TPM的卷烟烟气中CO含量也高;添加助燃剂有助于降低卷烟烟气中的CO,且对烟气TPM和焦油影响较小。     

气相色谱法测定卷烟烟气总粒相物中的烟碱

探讨了采用气相色谱法测定卷烟烟气总粒相物中烟碱的原理和方法，并与紫外分光光度法进行了比较。实验表明，两者的测定结果非常接近。与紫外分光光度法相比，气相色谱法具有快速、准确、简便等特点     

近红外光谱法预测烟气总粒相物中的烟碱含量

采用近红外(NIR)光谱技术直接扫描烟叶粉末,建立了预测烟气总粒相物中烟碱含量的数学模型。该模型的内部验证决定系数(R2)为86.57,均方差(RMSECV)为0.385;外部验证的决定系数(R2)为81.32,均方差(RMSEP)为0.398,近红外预测值与标准测定值的平均相对偏差为8.89%。通过配对t-检验,该方法与标准方法测定的效果无显著性差异。该方法精密度高,可用于烟气总粒相物中烟碱含量的快速预测。     

吸烟条件对卷烟主流烟气总粒相物pH的影响

分别对不同抽吸条件下卷烟主流烟气总粒相物的pH进行测定.结果表明:抽吸间隔时间和烟蒂长度是影响总粒相物pH的主要因素,抽吸持续时间和抽吸曲线对总粒相物pH的影响不大.人们可以通过改变吸烟间隔时间和烟蒂长度等方式控制卷烟的吸食品质.     

免试剂离子色谱（RFIC）法测定卷烟主流烟气总粒相物中的烟碱

建立了一种免试剂离子色谱分离,外标法校正,紫外检测器检测的烟碱分析方法。方法采用一款弱酸功能基的聚合物基质阳离子交换柱Ionpac CS19,梯度淋洗,可在短时间内完成卷烟主流烟气总粒相物中烟碱的分离和定量检测。离子色谱分析时,烟草中除烟碱之外含量最高的两种生物碱（新烟草碱和去甲基烟碱）与烟碱的分离度较好,能够满足烟碱的定量测定要求。烟碱标准品峰面积的相对标准偏差为0.49%（n=5）,商品卷烟5个平行样的相对标准偏差为2.3%。方法的检出限为0.8 μg/支,线性范围1.00~500.0 μg/mL,线性相关系数0.9999,加标回收率在93.2%~101.7%之间。检测来自中国烟草标准化研究中心的两个标准卷烟,测定结果为0.588和0.942 mg/cig,标准值分别为0.60±0.085,1.00±0.137 mg/cig,显示方法的准确度较好。研究结果为烟碱的测定提供了一种新的参考方法。      

测定卷烟烟气总粒相物主要影响因素的探讨

分别在不同的气流速度、温度、相对湿度和抽吸容量等测试条件下，测定了卷烟烟气总粒相物（即ＴＰＭ），并探讨了气流速度、温度、相对湿度和抽吸容量等因素与卷烟烟气中总粒相物的关系。实验结果表明，这些因素均对烟气总粒相物的测定产生影响。     

用HPLC法测定卷烟总粒相物及烟碱盐中的烟碱含量

在液相色谱测定烟叶中烟碱含量方法的基础上，测定了卷烟烟气总粒相物与烟碱盐中的烟碱含量，并与蒸馏－紫外法相对照，考核了所测结果的准确性、重现性和可靠性。     

烟丝和卷烟纸中金属元素对自由燃烧速率的影响

采用火焰原子吸收法测定42个不同牌号卷烟烟丝、卷烟纸及烟灰中8种金属元素的含量,并研究金属元素含量对烟支自由燃烧速率的影响。结果表明:钾、钠、镁、锰、锌、铜与卷烟烟支自由燃烧速率关系密切。其中,钾对烟支自由燃烧速率具有促进作用、镁为抑制作用,其余元素则因来源(卷烟纸或烟丝)差异呈现不同的影响趋势。     

基于香气活力值的烤烟烟叶清（青）香风格特征分析

为探究不同烤烟烟叶(玉溪C3F和许昌C3F复烤烟叶)的清香风格特征,采用半制备型高效液相色谱(HPLC)和气相色谱-质谱联用(GC-MS)等技术分离鉴定了浓香型和清香型烟叶主流烟气中的香气成分,确定了11种清(青)香成分,通过建立GC-MS内标标准曲线测定了其在烟叶主流烟气中的释放量,计算了相应的香气活力值(OAV),比较了11种清香成分对烟气清香香韵的贡献度,并基于OAV对两种烟叶的清香风格特征进行了分析。结果表明:(1)2种烟叶主流烟气中11种清香成分的总释放量分别为5.16和4.47μg/支,其中3-乙酰基吡啶和香叶基丙酮的释放量较高;(2)2种烟叶主流烟气中2-乙基己醇的OAV均小于1,对烟气清香香韵的贡献较小,β-大马酮和二氢大马酮的OAV均较大,在彰显烟气清香香韵方面起主要作用;(3)除OAV小于1的2-乙基己醇外,其余10种清香成分在玉溪C3F烟叶主流烟气中的总OAV为8.91×10⁶,是许昌C3F烟叶的5倍,这与玉溪C3F烟叶清甜香突出、清香明显的感官评价结果一致。     

基于形态学特征的对虾完整性识别方法构建

目的 针对对虾加工过程中缺损对虾混入完整对虾从而降低对虾产品外观品质的问题, 构建基于形态学特征的对虾完整性识别方法。方法 首先, 使用灰度差异法处理对虾图像, 经过连通域、中值滤波等形态学操作后, 得到较为完整的感兴趣区域图像, 再对其采取二值化、轮廓化等操作; 然后, 对轮廓提取骨架线, 并求轮廓内最大内切圆直径以得到长宽比特征, 并求其圆度特征; 最后, 将以上2个特征作为判别对虾完整性的核心指标, 构建融合特征判别算法。结果 本研究所提算法应用于1063幅生鲜虾测试集图像中识别准确率达到99.25%, 相比于传统曲率法, 识别准确率提升了6.48%, 识别时间降低了1598.6 ms。结论 该方法具有较大优势和应用前景, 为开发大规模南美白对虾在线品质的无损检测装备提供关键技术。     

国内外主要品牌卷烟主流烟气中气相自由基含量的对比分析

采用电子顺磁共振(EPR)自旋捕集法对国内外196种卷烟主流烟气中气相自由基含量进行了分析测定.结果表明:①卷烟主流烟气中气相自由基含量与焦油及烟碱检测值均无明显相关性,分析认为主要原因可能是卷烟配方中各单料烟的气相自由基含量差异较大;②在同等焦油盒标值下,国内烤烟型卷烟主流烟气中气相自由基平均含量远低于其它卷烟,国内外混合型卷烟主流烟气中气相自由基含量基本相近;③主流烟气中NO和气相自由基含量存在显著的线性相关性(R2=0.891).     

The Impact of Kilning on Enzymatic Activity of Buckwheat Malt

This study investigated the impact of kilning on α‐amylase, β‐amylase (total and soluble), β‐glucanase and protease activities in buckwheat malt. Common buckwheat (Fagopyrum esculentum) was steeped at 10°C for 12 h, germinated at 15°C for 4 days and kilned at 40°C for 48 h. Moisture content and enzymatic activities were determined throughout the kilning period. Results showed moisture content was reduced from 44% to 5% after 48 h of kilning at 40°C. β‐Amylase was found to exist in a soluble and latent form in buckwheat. Maximum activity of (a) α‐amylase, (b) total β‐amylase, (c) soluble β‐amylase, (d) β‐glucanase and (e) protease activity occurred after (a) 8, (b) 7, (c) 30, (d) 0, and (e) 8 h of kilning, respectively. The final malt exhibited very little β‐glucanase and cellulase activity. Proteolytic activity was low in buckwheat malt when compared to the barley malt control. All enzymatic activities were found to decrease during the kilning stage. Results indicated that after prolonged kilning at 40°C, inactivation of hydrolytic enzymes occurred; two‐stage kilning for shorter periods is recommended. Although, amylolytic activity was low in malted buckwheat, buckwheat malt shows potential as an ingredient for the brewing and cereal industry.     

用TOM评价中国面条品质的新方法及研究小麦品质对它的影响

本文以面条品尝鉴定方法（ＳＴ／Ｔ１０１３７－９３）和用于鉴定细条实心面（Ｓｐａｇｈｅｔｉ）品质的煮熟面条冲洗水中总有机物含量（ＴＯＭ）的方法，分别鉴定了２４个普通小麦品种（系）的面条煮面的品质，并研究了煮面品质与小麦品种籽粒及面粉的８个品质性状之间的相关关系。结果表明面条品尝鉴定评分与ＴＯＭ值之间有高度相关性。籽粒蛋白质含量与ＴＯＭ值呈显著负相关；蛋白组分中醇溶蛋白含量与ＴＯＭ值显著负相关；沉降值与ＴＯＭ值呈极显著负相关。通径分析表明，全蛋白含量对ＴＯＭ值的直接影响最大，剩余蛋白含量次之，醇溶蛋白含量列第三位；高分子量麦谷蛋白亚基组成与ＴＯＭ值间无明显关系；中分子量麦谷蛋白亚基组成与ＴＯＭ值关系密切，具有３８．８８ＫＤ亚基、５３．２５ＫＤ亚基或共有这两个亚基的品种，其面条ＴＯＭ值较低，面条品质优良。     

Influence of High Protein Digestibility Sorghums on Free Amino Nitrogen (FAN) Production during Malting and Mashing

In sorghum brewing, obtaining sufficient Free Amino Nitrogen (FAN) for rapid and complete fermentation remains a problem due to the high proportions of unmalted sorghum used and the poor digestibility of wet‐heat treated sorghum protein. Sorghum mutant lines with high protein digestibility have been developed through breeding. These high protein digestibility sorghums (HPDS) have protein bodies with villi‐like borders that apparently facilitate protease access. This work investigated FAN production from HPDS when malted and mashed, to assess their potential for use in sorghum brewing to improve wort FAN levels. When malted, HPDS contained substantially higher levels of FAN than normal protein digestibility sorghums (NPDS), 32 mg/100 g malt more. However, when the HPDS were mashed either as malt, or as grain or malt plus exogenous proteases, FAN production during mashing was not substantially higher than with NPDS subjected to the same treatments, only 6, 6–18 and 9–13 mg/100 g grain or malt, respectively. This is probably due to wet‐heat induced cross‐linking of the kafirin proteins reducing their susceptibility to proteolysis. Notwithstanding this, HPDS could be very useful for improving FAN levels in sorghum brewing if they are malted.     

Influence of free‐air CO2 enrichment (FACE) on the eating quality of rice

Rice plants (Oryza sativa L cv Akitakomachi) were grown under free‐air CO₂ enrichment (FACE) in farmers' fields in Shizukuishi, Iwate, Japan during 1999 and 2000. The grains were harvested and subsequently analyzed for protein and amylose contents as well as the traits related to cooked‐rice viscosity. The cooked rice was also subjected to sensory evaluation. The protein content of rice grains grown under elevated CO₂ was significantly lower than that of rice grown under ambient conditions. In addition, CO₂ enrichment increased the whiteness of the grains in both brown and milled rice and reduced their surface hardness. Although the amylose content of rice grains was unaffected, starch pasting properties demonstrated that rice grains in elevated CO₂ had higher maximum viscosity and breakdown than those grown in ambient conditions. Sensory evaluation of cooked rice with respect to umami (deliciousness), appearance, aroma, hardness, stickiness and overall palatability index indicated that the sensory properties were not significantly altered by the CO₂ enrichment treatment. Therefore, we conclude that the growth of the rice cultivar Akitakomachi under elevated CO₂ concentration decreased the protein content, but did not change the palatability to a level that may be detected by sensory taste panel evaluation. Copyright © 2005 Society of Chemical Industry     

Influence of environmental and genetic factors on health-related compounds in strawberry

Strawberry (Fragaria × ananassa, Duch.) represents a relevant source of micronutrients and phenolic substances, most of which are natural antioxidants and contribute to the high nutritional quality (NQ) of the fruit. Despite its proven health benefits, strawberries also contain allergenic compounds. In particular protein Fra a 1 is considered the main cause of allergic reactions after consumption of these fruits. However, there is a dearth of literature data on the genetic and seasonal influences on the Fra a 1 accumulation in strawberries, and on the quantitative variation of this allergen during fruit ripening.