川菜菜品的辣味物质分析与辣度分级

采用高效液相色谱法测定部分川菜菜品中辣味物质（辣椒素及二氢辣椒素）的含量,根据高效液相色谱分析结果结合感官评价进行辣味分级。根据辣度的强弱分为5级（特辣,辣椒素类物质含量≥0.291 8 g/kg）、4级（辣,辣椒素类物质含量0.092 4～0.291 8 g/kg）、3级（中辣,辣椒素类物质含量0.019 5～0.092 4 g/kg）、2级（微辣,辣椒素类物质含量0.001 95～0.019 5 g/kg）、1级（不辣,辣椒素类物质含量＜0.001 95 g/kg）5 个等级。在123 个样品中,1级样品占39.84%,2级样品占18.70%,3级样品占26.83%,4级样品占12.20%,5级样品占2.44%。实验还分析了辣椒及其制品对样品辣味的影响,样品的辣味不仅与辣椒及其制品的种类和使用量有关,还与加工方式、原料大小、加工温度、调味料等密切相关。     

辣味食品辣度量化分级技术研究

本文针对贵阳地区消费人群对辣味食品辣度的感官评价进行了调查,定量分析了不同辣度辣味食品中辣椒碱的含量,依据感官辣度和辣味食品中辣椒碱的含量,对辣味食品的辣度进行了量化,并分为4级:1级(微辣;辣椒碱含量<0.30%)、2级(中辣;辣椒碱含量0.30%～0.50%)、3级(辣;辣椒碱含量0.50%～0.70%)、4级(很辣;辣椒碱含量>0.80%)。在考虑辣椒原料综合利用的基础上,设计了定量添加辣椒精以生产不同辣度辣味食品的工艺路线。     

三系培育新品种朝天椒的农艺性状与品质特性研究

为新品种朝天椒的开发利用提供理论依据,以编号为1~5的5份不同杂交组合的三系培育新品种朝天椒种质资源为受试材料,采用综合方法分析了其农艺性状和以辣椒素含量和挥发性物质为主的品质特性。结果表明,5种朝天椒的农艺性状存在较大差异,其果长为6.7~9.3 cm,果重2.40~6.26 g,种子数比15.3~28.1个/g,果肉比71.10%~83.93%。5种朝天椒均具有较高的营养价值,但其营养品质有所不同。其中,1号朝天椒的碳水化合物、粗脂肪和灰分含量最高,2号朝天椒的水分含量最高,3号朝天椒的维生素C含量最高,5号朝天椒的蛋白质含量最高。5种朝天椒的辣椒素含量较高且具有较高的辣度,其中5号朝天椒的辣椒素类物质含量最高（1.128 g/kg）,斯科维尔指数为17399 SHU,辣度为116;2号朝天椒的辣椒素类物质含量最低（0.464 g/kg）,斯科维尔指数为7157 SHU,辣度为48。5种朝天椒中共检出100种挥发性物质,其中烯烃类物质的相对含量最高（39.20%~61.73%）,其共同的呈香物质主要为烯烃类、酯类和醇类,但该3类物质的种类与相对含量存在较大差异。Pearson相关性分析结果显示,新品种朝天椒的辣度与其果重和果肉比呈极显著负相关（P<0.01）,与其种子数比呈极显著正相关（P<0.01）。综合分析认为,5种新品种朝天椒均具有较高的辣度和营养价值、良好的色泽和香气,均是加工干椒的适宜品种,尤其是5号,且2号、3号和4号朝天椒还可鲜食、泡制、腌制或发酵。     

花椒麻度分级的改良斯科维尔指数法建立研究

针对辣椒辣度的斯科维尔指数（Scoville heat units,SHU）法存在对基质影响因素的忽略及检验结果缺乏统计学依据的问题,通过将单样品评价改为样品液与制备基质对照液的成对比较检验,以及增加评价小组人数或评价轮次改进实验设计等,建立了与辣味同为三叉神经感的花椒麻味感觉强度的间接测量方法--改良SHU法。应用新方法对花椒（Zanthoxylum bungeanum Maxim.）麻度进行测量与分级,并同时采用紫外分光光度计法对花椒中的酰胺含量进行了测定。结果表明：麻味感觉强度值与花椒酰胺的物理含量之间具有一定的一致性,但对某些品种而言,相近的或者较低的花椒酰胺含量表现出更强的麻感,较高的酰胺含量却能表现出较低的麻感。说明,花椒麻味感觉强度不仅与其所含的花椒酰胺总含量相关,也与花椒酰胺的构成及其结构相关。该方法的建立对花椒麻度相关研究以及应用麻度作为核心指标进行花椒及其制品质量评价与控制具有重要的理论和实践意义。     

高效液相色谱法测定火锅底料中辣椒素类物质

为了测定火锅底料中的辣味物质(辣椒素及二氢辣椒素),建立了高效液相色谱快速检测方法:色谱柱为C18InertSustain(4.6 mm×250 mm,5μm),流动相为甲醇和水(V/V,65∶35),流速1.0mL/min,柱温30℃,进样量10μL,检测波长280nm。辣椒素类物质的提取采用超声波辅助提取。结果表明:火锅底料中的辣椒素类物质含量在0.256~0.816g/kg之间,斯科维尔系数在3948~12583SHU。     

“郫县豆瓣”色价和辣度的分析

以某品牌特、一、二级"郫县豆瓣"为样本,分别选择索氏提取、丙酮超声波提取以及乙酸乙酯超声波提取其中的辣椒红色素,通过分光光度法检测其吸光度,对比分析色价差异;采用高效液相色谱法测定其中辣椒素和二氢辣椒素的含量,采用国际通用的斯科维尔指数和辣度来表示"郫县豆瓣"的辣味程度。结果表明:丙酮超声波提取法提取效果最好,可用于"郫县豆瓣"的色价测定,各等级"郫县豆瓣"的色价均高于0.4,随着等级的降低而减小,但各等级间差异不显著;超声波提取、高效液相色谱法测得某品牌特级"郫县豆瓣"的辣度为23~28;一级为14~21;二级为13~15。     

辣椒红色素提取工艺的研究

采用正交实验设计法,以总色价、收率、总能耗为指标,对传统辣椒红色素提取工艺进行优化改进,得到最佳提取条件:辣椒∶丙酮=1(g) ∶ 9(mL),提取时间180min,提取温度90℃,总色价82.28,收率11.15%,单位能耗0.26元/g;并采用抗氧化除辣及皂化去酯的方法去除辣味,使辣椒红色素的色价提高到250～320之间.     

口含烟对人口腔致病菌的影响

  目的  研究口含烟对人口腔卫生的影响。  方法  将3种不同类型口含烟（胶基型、袋装型、含片型）提取物和传统卷烟烟气总粒相物（TPM）基于烟碱含量配成不同浓度,研究其对变形链球菌和牙龈卟啉单胞菌的抑菌效应。选取20名志愿者吸食3种口含烟和传统卷烟,以吐取法采集吸食前5 min和吸食后0~2min,2~5 min,5~10 min,10~15min,90~95 min共6个时间段的唾液,提取唾液中细菌DNA,通过实时荧光定量PCR（探针法）检测各时间节点总细菌、变形链球菌和牙龈卟啉单胞菌水平。  结果  （1）3种口含烟在体外对2种细菌无抑菌作用,普通卷烟TPM有一定抑菌作用。（2）吸食袋装型、含片型口含烟和传统卷烟后,唾液中细菌总量短期有所降低,但1 h后均恢复至使用前水平。牙龈卟啉单胞菌与变形链球菌量变化趋势与总细菌基本一致。  结论  口含烟及传统卷烟在吸食后短期内对口腔微生物有抑制作用。      

湖南省卫生厅关于协查“东方亿力神^MT参葡颐年片”的请示

我厅在现场卫生监督检查中采集的由“中澳合资西安超英攀达化妆品有限公司”生产的“东方亿力神^tm参葡颐年片”（规格O．6g／&;#215;4片／盆；生产日期：20050508；批准文号：国食健字G20040119；卫生许可证号：陕卫食健准字[2004]第0011号），经我省疾病预防控制中心检测（2005SP0533）发现：含“枸椽酸西地那非”69．4mg／g。违反了《中华人民共和111食品卫生法》第九条第八项、第十条的规定。     

栘[木衣]属植物多酚的含量测定与比较

以根皮苷为标样,研究Folin-Ciocalteu（FC）比色法测定栘[木衣]属3 个种的多酚含量适宜条件,进一步用此改良法测定和比较多酚含量在栘[木衣]属的3 个种的叶以及在长爪栘[木衣]的不同器官中的差异性。结果表明,FC比色法最佳测定条件为：加质量分数10%的Na2CO3溶液2.5 mL和FC显色剂0.5 mL,在55 ℃条件下反
应7 min。在1.252～15.024 μg/mL范围内,根皮苷的吸光度与其质量浓度呈良好的线性关系（R2=0.999 1）,平均加样回收率为（100.08±2.43）%;测定结果还表明,3 个物种的叶片多酚含量的差异显著,云南栘[木衣]最低12.55 g/100 g,长爪栘[木衣]最高25.35 g/100 g;长爪栘[木衣]的不同器官均含有多酚类化合物,含量差异显著（3.75～25.35 g/100 g）（P＜0.05）,由低到高为：果核＜根＜果肉＜根皮＜果皮＜茎＜叶。结论：改良后的FC比色法,用于测定栘[木衣]的多酚含量,具有快速、准确、重复性好的特点。栘[木衣]属植物的多酚含量较高,且多酚含量有明显的种间差异性及部位的差异性,栘[木衣]属的植物具有较大的开发和应用价值。     

The influence of beverages on residual spiciness elicited by eating spicy chicken meat: time‐intensity analysis

This study aimed to determine whether five types of beverage, milk (3.3% fat), oolong tea, tomato juice, sparkling water and spring water, reduce the residual spiciness elicited by eating spicy chicken over time. After tasting a piece of spicy popcorn chicken, participants were asked to drink one of five beverages one after another and rate the spiciness intensity using the time‐intensity (TI) analysis. Based on the TI parameters, milk was found to be the best beverage to reduce residual spiciness of spicy chicken over time. Participants rated milk the most effective in decreasing residual spiciness of spicy chicken. Partial least squares regression revealed that the three TI parameters, area under the curve, decreasing area and increasing area, are the best predictors of the self‐reported ratings for spiciness‐reduction effect of individual beverages. In conclusion, this study shows that milk (3.3% fat) can be used as a palate cleanser for spicy chicken.     

Short communication: salivary secretion during meals in lactating dairy cattle

Four multiparous Holstein cows in midlactation were used in a 4 × 4 Latin square to evaluate whether source of forage influenced salivary secretion during eating in lactating dairy cows. The forages were allocated separately from the pelleted concentrates. Cows were offered 1 of 4 forages each period: barley silage, alfalfa silage, long-stemmed alfalfa hay, or chopped barley straw. Saliva secretion was measured during the morning meal by collecting masticates through the rumen cannula at the cardia of each cow. Rate of salivation (213 g/min) was not affected by forage source. However, the forage sources differed in eating rate (g of DM/min), which led to differences in ensalivation of forages (g of saliva/g of DM and g of saliva/g of NDF). On the basis of DM, ensalivation (g of saliva/g of DM) was greatest for straw (7.23) and similar for barley silage, alfalfa silage, and alfalfa hay (4.15, 3.40, and 4.34 g/g of DM, respectively). Higher ensalivation of straw could be accounted for by its higher neutral detergent fiber (NDF) content; ensalivation of NDF (g of saliva/g of NDF) was actually greatest for long-stemmed alfalfa hay (12.4) and similar for the other chopped forages (8.9). Cows consumed concentrate about 3 to 12 times faster than the various forages (DM basis), and ensalivation of concentrate was much lower (1.12 g of saliva/g of DM) than for forages. Feed characteristics such as particle size, DM, and NDF content affect salivary output during eating by affecting the eating rate. Slower eating rate and greater time spent eating may help prevent ruminal acidosis by increasing the total daily salivary secretion in dairy cows.     

辣味感觉的产生及其调控机制研究进展

辣椒素类物质是辣椒果实中“辣味”的来源,辣椒素类物质通过刺激神经末梢,在神经末梢上和某些分子反应产生生物电脉冲,激活人体神经中的辣椒素受体通道,然后将信号传导到大脑,产生辣味感觉（以下简称辣味）。研究发现,辣味与味觉之间存在协同或抑制作用,不同浓度的辣椒素类物质与味觉的相互作用也不同,因此,本文对辣椒素类物质的种类、化学性质及应用进行概括,阐述辣味的产生,即辣椒素激活辣椒素受体通道的生物学机制,同时探讨辣味与酸味、甜味、苦味、咸味以及鲜味的相互作用,指出目前辣味与味觉相互作用及其潜在影响机制研究方面存在的不足,并展望未来的研究方向,以期为辣味产业的进一步发展提供理论支持。     

Rice bolus texture changes due to α-amylase

During mastication, starch hydrolysis caused by salivary α-amylase may influence food bolus formation and subsequent breakdown during gastric digestion. The objective of this study was to examine texture changes of rice boluses after simulated mastication. Boluses were prepared with three varieties each of brown and white rice (short, medium, and long grain). After simulated mastication, rice boluses were incubated from 0 to 180 min at 37 °C prior to texture measurement by bulk compression. Saliva was added at concentrations of 0.1 and 0.2 mL saliva/g rice. Boluses were also formed with 0.1 mL/g saliva without α-amylase. The peak force and area under the compression curve were significantly influenced by rice type, saliva level, and incubation time (p < 0.0001). The peak force of the boluses decreased, on average, from 127 to 52 N for brown rice and 111 to 54 N for white rice. Changes in bolus texture were described by a linear-exponential model. For all rice types, bolus texture was significantly lower in the presence of α-amylase. Saliva amount and presence of α-amylase influenced the textural properties of rice boluses during 180 min of incubation. These factors should be carefully considered in future in vitro studies of carbohydrate-based food products.     

Older US adults like sweetened colas,but not other chemesthetic beverages

Many older adults suffer from difficulty swallowing thin beverages like water or coffee. To improve swallowing safety, beverages are typically thickened. This creates a new problem: the thickened beverages can be disgusting. New research suggests chemesthesis, particularly spiciness, carbonation, or intense sourness, could improve swallowing without the need for thickeners. Yet, whether such beverages would be liked by older adults is unknown. We thus conducted this experiment to establish older adults' sensory perception and liking/disliking of commercially available chemesthetic beverages. We recruited participants to rate sweetness, sourness, fizziness, stinging, and liking/disliking of unsweetened carbonated waters (1 plain, 5 flavored), sour orange juice, spicy ginger beer, and colas (sugar or aspartame-sweetened). Initial tests (N = 30 older adults) indicated sour orange juice, spicy ginger beer, and two of the flavored waters were not well-liked, so other beverages were selected for a second test (N = 94, 30 younger adults, 64 older adults). Sweetened, carbonated colas were the best-liked of the beverages. The unsweetened, flavored carbonated waters were in general not liked. Regarding comparisons of sensory ratings between older and younger adults, only sweetness differed between age groups. In particular, intensity ratings for the chemesthetic aspects of the beverages (stinging/burning/spiciness, fizziness) and the sour taste did not differ by age. As the chemesthetic properties are the most likely reason the beverages could aid in swallowing safety, observing no suppression of these sensations in older adults is encouraging for the potential of these products as a treatment option.     

Differences in salivary flow and composition between age groups are correlated to dynamic retronasal aroma perception during wine consumption

Salivary flow and composition have been related to the dynamics of retronasal aroma release during wine consumption. However, whether differences in saliva composition among age groups are related to wine aroma perception remains unexplored. Therefore, the aim of this work has been to determine the relationship between salivary parameters and the dynamics of wine retronasal aroma perception in two groups of individuals of different age (young and senior adults). To do so, 22 individuals, 11 from the young group (18–35 years old) and another 11 from the senior group (>55 y.o.) were recruited for this study. The retronasal aroma intensity of two specific aroma attributes (smoked and black pepper) of a red wine was rated by using Time-Intensity (TI) methodology. Saliva was previously collected from each individual. Salivary flow and composition (pH, total protein content, protease and α-amylase activities) were determined in order to characterise the two groups of panellists. Results showed significant differences among age groups (young and seniors) in the TI parameters extracted from the dynamics curves of retronasal aroma perception of both attributes. Thus, smoky and black pepper notes were more intensely rated and for longer times by the senior group than by the younger group. Salivary parameters were also significantly different in both age groups. A significant positive correlation between the salivary total protein content and the maximum intensity (Imax) perceived, and a significant negative correlation between the salivary flow and most TI parameters (Imax, area under the curve and duration time of the perceived stimuli) were found for both aroma attributes.     

2015年吉林省地方特色食品辣白菜中常用添加剂和硝酸盐含量监测结果分析

目的：分析了解2015年吉林省特色食品朝鲜族辣白菜的质量状况,为今后开展风险评估、制定地方标准、跟踪评价企业标准提供数据资料。方法：分别在延边州地区、吉林市地区、长春市地区、通化市地区和白城市地区等超市、农贸市场采集100份辣白菜样品,采用分光光度法和液相色谱法测定硝酸盐、亚硝酸盐、苯甲酸、山梨酸和糖精钠的含量,并根据《食品安全国家标准 食品添加剂食用标准》(GB 2760-2014),对检测结果进行分析评价。结果：吉林省地方特色食品朝鲜族辣白菜中苯甲酸、山梨酸、糖精钠和亚硝酸盐都有不同程度的检出,检出率分别为34%、19% 、5%和82%,其中各有1份样品苯甲酸、山梨酸含量超标,有2份样品中亚硝酸盐含量超标;所有样品中均检出硝酸盐,检出含量范围为114mg/kg—3010mg/kg。结论：定型包装的辣白菜要重点监测食品添加剂的使用情况,同时由于硝酸盐和亚硝酸盐的含量和检测率都比较高,建议应避开腌渍初期食用辣白菜。     

Effect of dietary roughage level on chewing activity,ruminal pH,and saliva secretion in lactating Holstein cows

Increasing dietary roughage level is a commonly used strategy to prevent subacute ruminal acidosis. We hypothesized that high-roughage diets could promote chewing activity, saliva secretion, and hence more alkaline to buffer rumen pH. To verify the hypothesis, 12 multiparous Holstein cows in mid lactation were randomly allocated to 4 treatments in a triplicated 4 × 4 Latin square experiment with one cow in each treatment surgically fitted with a ruminal cannula. Treatments were diets containing 40, 50, 60, or 70% of roughage on a DM basis. Increasing dietary roughage level decreased DM, CP, OM, starch, and NE_L intake, increased ADF intake, and decreased milk yield linearly. Intake of NDF was quite stable across treatments and ranged from 7.8 to 8.1 kg/d per cow. Daily eating time increased linearly with increased roughage level. The increase in eating time was due to increased eating time per meal but not number of meals per day, which was stable and ranged from 8.3 to 8.5 meals per day across treatments. Increasing dietary roughage level had no effect on ruminating time (min/d), the number of ruminating periods (rumination periods per d), and chewing time per ruminating period (min/ruminating period). Ruminating time per kilogram of NDF intake and total chewing time per kilogram of ADF intake were similar across treatments (57.4 and 183.8 min/kg, respectively). Increasing dietary roughage level linearly increased daily total chewing time; linearly elevated the mean, maximum, and minimum ruminal pH; and linearly decreased total VFA concentration and molar proportion of propionate in ruminal fluid. Saliva secretion during eating was increased, the secretion during rumination was unaffected, but the secretion during resting tended to decrease with increased dietary roughage level. As a result, total saliva secretion was not affected by treatments. In conclusion, the results of the present study did not support the concept that high-roughage diets elevated ruminal pH through increased salivary recycling of buffering substrates.     

Effect of concentrate level and feeding management on chewing activities,saliva production,and ruminal pH of lactating dairy cows

Eight ruminally cannulated lactating Holstein cows were used in a double 4 x 4 Latin square to determine the effects of 1) proportion of barley silage [40, 50, and 60% of dry matter (DM)] in the diet, and 2) feeding a total mixed ration (TMR) compared with separate ingredients (SI) on chewing activities, saliva production, and ruminal pH. Although cows fed SI were offered a diet containing 50% silage, they actually consumed a diet containing 43% silage (DM basis). Dry matter intake and milk yield were similar for all diets (18.2 kg of DM/d and 27.2 kg/d, respectively). Cows fed the 40% silage TMR spent more time eating than cows fed SI (243 vs. 198 min/d), but rumination time was similar (546 min/d). Eating time was similar among the TMR diets, but rumination time increased from 498 to 516 and 584 min/d as silage in the TMR increased from 40 to 50, and then to 60%, respectively. The secretion of saliva per gram of feed was 4.43, 3.18, and 1.19 ml/g of DM with consumption of silage, TMR, and concentrate, respectively. Resting salivation rate was similar for all diets (101 ml/min). Regardless of the diet, cows secreted 239 +/- 17 L/d of saliva, and ruminal pH was below 5.8 for 10 h/d. Results indicated increased chewing time did not increase total daily saliva secretion because increased eating and ruminating saliva was associated with decreased resting saliva. Feeding SI increased the risk of acidosis, because cows ate a higher proportion of concentrate than intended.     

Salivary lipase and α-amylase activities are higher in overweight than in normal weight subjects: Influences on dietary behavior

Mounting evidence shows that hedonic eating, leading to overeating just for pleasure, can be driven by oro-sensory factors through the activation of reward processing and learning in the brain. Foods rich in sugars and fats are potent rewards and saliva composition influences oral taste, texture and aroma perception. A role for salivary α-amylase and lipase in the gustatory system and a link between salivary α-amylase activity and dietary habits were recently hypothesized.The objective of this study was to verify the relationship among salivary lipase and α-amylase activities as well as zinc concentration with food preference and choice of people with different body mass indices.Forty-two (23 normal weight and 19 overweight) healthy subjects participated in the study. Data showed that α-amylase and lipase were 1.8 and 2.4 folds higher in overweight than in normal weight subjects, respectively. On the other hand, overweight subjects showed a 33% reduced salivary zinc concentration compared to normal weight subjects. Only lipase activity positively correlated with individual preference for high-fat foods and with fat content of the diets.All in all data suggested that high salivary lipase activity in overweight subjects could be an adaptive response to the low fat-taste perception related to the reduced zinc concentration. It cannot be ruled out that other factors but diet might influence salivary α-amylase activity in overweight subjects.