Determination of absolute threshold and just noticeable difference in the sensory perception of pungency

Absolute threshold and just noticeable difference (JND) were determined for the perception of pungency using chili pepper in aqueous solutions. Absolute threshold and JND were determined using 2 alternative forced-choice sensory tests tests. High-performance liquid chromatography technique was used to determine capsaicinoids concentration in samples used for sensory analysis. Sensory absolute threshold was 0.050 mg capsaicinoids/kg sample. Five JND values were determined using 5 reference solutions with different capsaicinoids concentration. JND values changed proportionally as capsaicinoids concentration of the reference sample solutions changed. Weber fraction remained stable for the first 4 reference capsaicinoid solutions (0.05, 0.11, 0.13, and 0.17 mg/kg) but changed when the most concentrated reference capsaicinoids solution was used (0.23 mg/kg). Quantification limit for instrumental analysis was 1.512 mg/kg capsaicinoids. Sensory methods employed in this study proved to be more sensitive than instrumental methods. Practical Application: A better understanding of the process involved in the sensory perception of pungency is currently required because "hot" foods are becoming more popular in western cuisine. Absolute thresholds and differential thresholds are useful tools in the formulation and development of new food products. These parameters may help in defining how much chili pepper is required in a formulated product to ensure a perceptible level of pungency, as well as in deciding how much more chili pepper is required in a product to produce a perceptible increase in its pungency.     

Lifting properties of the alkamide fraction from the fruit husks of Zanthoxylum bungeanum

The fruits of various Zanthoxylum species are used as a spice in the Chinese and Japanese cuisine because of their delicate flavour and tingling properties. The lipophilic hydroxyalkamides hydroxy α‐ and β‐sanshools ( 1a,b ) have been identified as the tingling principles of these plants, and previous studies have validated a sanshool‐rich lipophilic extract from the fruit husks of Z. bungeanum Maxim. (Zanthalene^®) as an anti‐itching cosmetic ingredient. Because tingling is a sort of ‘paralytic pungency’, and Zanthalene^® potently inhibits synaptic transmission, we have investigated its capacity to relax subcutaneous muscles and act as a topical lifting agent for wrinkles. An anti‐wrinkles extract rich in spilanthol ( 2 ), a lipophilic alkamide having sensory properties similar to those of Zanthalene^®, was used as a reference. Short‐term (lifting effect) and long‐term (anti‐wrinkle) improvements of skin roughness parameters were evaluated by both objectives’ and subjectives’ measurements. An immediate ‘lifting’ effect was observed with the sanshool‐rich lipophilic extract, at dosages at which the reference alkamide extract was inactive in the objective assays. Limited desensitization after repeated application and good overall tolerability were observed, although a modest long‐term anti‐wrinkle effect was shown by both products. Taken together, these observations validate the use of sanshool‐rich lipophilic extracts as an efficacious, immediate‐action lifting agent, and exemplify the relevance of sensory observations to foster the development of innovative cosmetic ingredients.     

Pungency in food perception and preference

Abstract

While sensations of pungency are characteristic of food in all cultures, relatively little attention has been given to trying to understand the role these sensations play in our perception of, and preference for, foods and food flavors. This review provides an overview of research on the psychophysics of the sensory system responsible for perception of pungency (the trigeminal nerve), current views on how preference for pungency develops, and the qualities of common pungent food ingredients and their interactions with food flavors. It is argued that understanding the role that pungency plays in foods is essential to successful development of acceptable food flavors, especially for those markets in Asia in which pungency is a defining characteristic of the cuisine.     

Inhibitory effect of Zanthoxylum bungeanum maxim. and Capsicum annuum L. on the activities of pancreatic lipase and α-amylase

Zanthoxylum bungeanum maxim. (ZBM) and Capsicum annuum L. (CAL) are popular condiments in China. In this study, the inhibition of pancreatic lipase and α-amylase by ZBM and CAL extracts, as well as catechin, rutin, hydroxy-α-sanshool (from ZBM extract) and capsaicin (from CAL extract), was determined. The half maximal inhibitory concentration (IC₅₀) values of ZBM extract, CAL extract, rutin, hydroxy-α-sanshool and capsaicin against pancreatic lipase were 82.1, 533.5, 583.8, 565.7 and 62.4 μg mL⁻¹, respectively, while that against α-amylase were 125.6, 1167.2, 213.2195.6 and 163.2 μg mL⁻¹, respectively. Catechin had no detectible inhibition on the two enzymes even at 4 mg mL⁻¹. The combination of hydroxy-α-sanshool and capsaicin against the two enzymes showed similar inhibition trends to that of ZBM and CAL extracts (synergism at low concentrations but antagonism at high concentrations), suggesting the two compounds were closely associated with the functions of the crude extracts. The results obtained from the in vitro digestion were similar but with a lower inhibition rate. Kinetic studies revealed that ZBM extract, hydroxy-α-sanshool and capsaicin showed mixed-type inhibition for pancreatic lipase and α-amylase. Molecular modelling suggested capsaicin had a higher affinity to the two enzymes, with glide scores of −8.18 and −7.87 kcal mol⁻¹, respectively.     

Potential of Szechuan pepper as a saltiness enhancer

The flavor profile, flavor enhancement, and saltiness modulation of Szechuan pepper (Zanthoxylum simulans) were analyzed to evaluate its effectiveness in lowering salt usage. The saltiness enhancing efficiency of Szechuan pepper and its salt-reduction properties were determined to be 28.74% and 22.32%, respectively. The saltiness enhancers were detected in the polar fraction and taste dilution analysis combined with half-tongue test determined the most potent saltiness enhancing components in chromatographic subfractions. Both spectroscopic analysis and sensory evaluation disclosed NaCl as the unexpected primary contributor of saltiness enhancement in this spice. It is the first known study revealing Szechuan pepper’s high salt content.     

Characterization and Comparison of the Pungent Components in Commercial Zanthoxylum bungeanum Oil and Zanthoxylum schinifolium Oil

In the present study, the characterization and comparison of the pungent components in commercial Z. bungeanum oils and Z. schinifolium oils were investigated. By high‐performance liquid chromatography (HPLC)‐mass spectrometry (MS/MS) analysis, the major alkylamides in Z. bungeanum and Z. schinifolium oils were identified as hydroxy‐ε‐sanshool, hydroxy‐α‐sanshool, hydroxy‐β‐sanshool, hydroxy‐γ‐sanshool, hydroxy‐γ‐isosanshool, bungeanool, isobungeanool, and tetrahydrobungeanool, respectively. Hydroxy‐α‐sanshool was found to be the most abundant alkylamide in all oils. The levels of hydroxy‐ε‐sanshool and hydroxy‐β‐sanshool in Z. bungeanum oils were comparable to that in Z. schinifolium oils, whereas Z. bungeanum oils contained significantly (P less than 0.05) higher levels of hydroxy‐γ‐isosanshool, bungeanool, isobungeanool, and tetrahydrobungeanool, compared with Z. schinifolium oils. Furthermore, principal component analysis (PCA) indicated that Z. bungeanum oil and Z. schinifolium oil were clearly classified by HPLC fingerprinting profiles and concentrations of alkylamides. In addition, the results of PCA suggested that alkylamides, such as hydroxy‐γ‐sanshool and bungeanool, could be potential markers to distinguish Z. bungeanum oil and Z. schinifolium oil. The results from this study could be used to discriminate the different flavor characterization and control the quality of commercial Z. bungeanum oil and Z. schinifolium oil.     

Extraction and Purification of Quercitrin,Hyperoside, Rutin,and Afzelin from Zanthoxylum Bungeanum Maxim Leaves Using an Aqueous Two‐Phase System

In this study, an aqueous two‐phase system (ATPS) based on ethanol/NaH₂PO₄ was developed for the extraction and purification of quercitrin, hyperoside, rutin, and afzelin from Zanthoxylum bungeanum Maxim leaves. These 4 flavonoids were 1st extracted from dried Z. bungeanum leaves using a 60% ethanol solution and subsequently added to the ATPS for further purification. The partition behavior of the 4 flavonoids in ATPS was investigated. The optimal ATPS conditions were: 29% (w/w) NaH₂PO₄, 25% (w/w) ethanol concentration, 1% (w/w) added amount of leaf extracts, no pH adjustment, and repeated 1 h extractions at 25 °C. Under the optimal conditions for the 10 g ATPS, the absolute recovery of quercitrin, hyperoside, rutin, and afzelin reached 90.3%, 83.5%, 92.3%, and 89.1%, respectively. Compared to the 60% ethanol extracts, the content of quercitrin (44.8 mg/g), hyperoside (65.6 mg/g), rutin (56.4 mg/g), and afzelin (6.84 mg/g) in the extracts increased by 49.9%, 38.8%, 45.6%, and 36.8% respectively. The extracts after ATPS also exhibited stronger antioxidant activities, the 2,2‐diphenyl‐1‐picrylhydrazyl IC₅₀ value (10.5 μg/mL) decreased by 41.8%, and the 2,2‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt value (966 μmol Trolox/g) and ferric reducing power value (619 μmol Trolox/g) increased by 29.8% and 53.7%, respectively. Furthermore, scale‐up experiments indicated that a larger scale experiment was feasible for the purification of the 4 flavonoids.     

Capsaicin accumulation is related to nitrate content in placentas of habanero peppers (Capsicum chinense Jacq.)

BACKGROUND: The presence of capsaicin, the pungent principle of peppers, is restricted to the fruits of hot cultivars. This compound, which is produced in the fruits' placenta, requires 3 mol of nitrogen to be formed. Hence nitrogen availability may affect pepper pungency through its content in the fruit tissues. On the other hand, potassium may also affect pepper pungency given its positive effect on fruit development. In order to address this issue, plants of habanero pepper (Capsicum chinense Jacq.) were hydroponically cultured with various doses of nitrate and potassium and the contents of these ions and capsaicin were analyzed in the different fruit tissues. RESULTS: Treatments did not produce major effects on pod yield or size during the experimental period, and pepper pods from plants growing under low nitrate concentrations presented no significant differences in total nitrate content. However, lower nitrate, as well as low capsaicin contents, were found in the isolated placentas from peppers grown on the lowest nitrate doses. Variations in potassium availability resulted in differences in pod production per plant, but not in capsaicinoid accumulation. CONCLUSION: Under the assayed conditions, nitrate content in the placenta affects capsaicin synthesis. Copyright © 2010 Society of Chemical Industry     

红树莓花色苷的提取及抗氧化活性研究

采用酸化乙醇法提取红树莓中的花色苷,通过正交试验确定花色苷提取的最佳条件,同时对红树莓花色苷提取物的抗氧化活性进行研究。结果表明,以盐酸酸化的80%乙醇溶液(pH3)按1:20(g/mL)的料液比在60℃提取红树莓1.5h,此条件下,鲜果中花色苷提取量达0.625mg/g。在实验范围内,红树莓花色苷提取物的还原能力、对羟自由基和超氧阴离子自由基的抑制率均随质量浓度的升高而增加。红树莓花色苷提取物抑制羟自由基和超氧阴离子自由基的半数有效浓度(EC50)分别为0.175mg/mL和0.699mg/mL,说明红树莓花色苷提取物抑制羟自由基比抑制超氧阴离子自由基的能力强。     

川菜烹饪复合调味料的研制

传统川菜调味料在烹调过程中,表现出的调味力不定、效率低及调味准确性、可操作性、使用方便性较差等特点.依据风味化学原理和人的味感生理特性,采用工程法复合调味品的制作原理和技术方法,对传统川菜调味料的生味成分进行转化、分离、加工和复配,制成符合川菜食俗及风味、调味力强、使用方便的4种川菜复合烹饪调味料类型,分别为辛辣型、香辣型、辛香型和清香型。     

Studies on the chemical and flavor qualities of white pepper (Piper nigrum L.) derived from five new genotypes

Here, we examine the chemical quality (total protein, total lipid, starch, piperine, and essential oil) and flavor quality of white pepper (Piper nigrum L.) derived from five new genotypes (Jianyin-1, Banyin-1, Banyin-2, Banyin-3, and Banyin-4). We employed headspace solid-phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC-MS) to analyze major volatiles, electronic nose (E-nose) to analyze volatiles of unknown nature, and sensory testing to assess flavor quality of white pepper derived from these five genotypes. The piperine and essential oil values were significantly higher in Jianyin-1 than in any of the other samples, and this was in accordance with the sensory evaluation results, which indicated that this sample also possesses the most intense pungency notes of all of the samples. The characterization of the chemical quality, volatile compounds, and volatile profiles of all five pepper cultivars showed a clear difference between Jianyin-1 and all of the other samples, perhaps indicative of its unique hybrid origin for the four latter genotypes. The E-nose pattern matching used to examine the volatiles of unknown nature of white pepper derived from all five genotypes further supported our sensory and instrumental data and suggested that Jianyin-1 is a promising and pungent pepper cultivar useful for cultivation for human consumption.     

雪松松针乙醇提取物的抗氧化活性及构效关系研究

研究雪松松针乙醇提取物的抗氧化活性及构效关系。通过体外化学分析法,测定雪松松针乙醇提取物的抗氧化活性;采用福林酚法和三氯化铝法,测定其总酚和总黄酮含量;利用高效液相色谱-质谱联用(HPLC-MS)与核磁共振(NMR)技术,鉴定其主要成分,并对其抗氧化作用的构效关系进行初步探讨。结果表明,雪松松针乙醇提取物对实验体系中的ABTS(EC₅₀:0.48±0.01 mg/mL)和DPPH(EC₅₀:32.40±0.76 μg/mL)自由基有很好的清除作用,能够高效地清除羟自由基(EC₅₀:1.73±0.01 mg/mL)和过氧化氢(EC₅₀:89.48±0.54 μg/mL)中的活性氧,抑制脂质过氧化(EC₅₀:9.85±0.14 mg/mL)并具有较高的还原能力,展现出显著的抗氧化活性;提取物拥有较高的总酚(40.30±2.13 mg没食子酸当量/g提取物)和总黄酮(56.62±1.53 mg芦丁当量/g提取物)含量;甲基松柏苷、阿魏酸-β-D-吡喃葡萄糖苷、荛花酚、断氧化马钱苷、(E)-1-O-对香豆酰-α-D-吡喃葡萄糖苷和天竺葵素-3-O-葡萄糖苷是松针乙醇提取物的主要成分,这些化合物结构中大量存在的具有氢原子转移或单电子转移能力的酚羟基、甲氧基、苄基等基团,是其展现良好抗氧化活性的重要原因。     

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。     

Lipase-catalyzed synthesis of pungent capsaicin analogues

Pungency in peppers (Capsicum spp.) is a sensation produced by a group of molecules known as capsaicinoids. Capsaicin has been reported as the capsaicinoid with the strongest pungency. Based on the molecular structure of capsaicin the enzymatic synthesis and pungent properties of structural analogues was investigated. These analogues were based on modification of the length of the acyl chain (from C4 to C16) and the chemical substituents of the aromatic ring (–OH and –OCH₃). The syntheses were carried out in 2-methyl-2-butanol with lipase B of Candida antarctica, with conversions ranging from 83% to 97.5%. The initial reaction rates were not significantly influenced by the nature of acyl-donor but rather by the substituents in the aromatic ring of the evaluated amines. The relative pungency of 10 capsaicin analogues was sensorially evaluated, using a sensory method for relative pungency. All the compounds were tested at a dose equivalent to 20 times the threshold capsaicin concentration. Two analogues were found pungent; the vanillylamides of caprylic (C-8) and capric (C-10) acids, showing a relative pungency of 66% and 36%, respectively, while the vanillylamides of caproic (C-6) and lauric (C-12) acids had a very low relative pungency (2.1% and 1.2%, respectively). From these results structural features related to pungency are discussed.     

不同品种泡辣椒对特色川菜泡椒猪肝感官品质的影响

泡辣椒具有制作简单,增进食欲,增强菜肴风味的作用,是四川常用的一种调味料.文章分别选择了川菜制作中5种常用的泡辣椒品种,用于制作传统川菜泡椒猪肝.采用层次分析法进行权重分配,通过模糊数学法对5种菜品的感官质量进行了综合评定.结果 表明,不同品种的泡辣椒对泡椒猪肝感官品质的影响各异,添加了二荆条的菜品感官评分最高,添加了...     

不同工艺制备辣椒籽油的体外抗氧化活性比较

采用体外抗氧化活性试验模型,以Vc和VE作对照,比较研究超临界CO_2萃取、石油醚萃取及超临界CO_2萃取后脱色脱胶3种工艺制备的辣椒籽油的体外抗氧化活性。结果表明,不同工艺制备的辣椒籽油的还原能力以及对羟基自由基、超氧阴离子自由基和H_2O_2的清除率从高到低依次为超临界萃取后脱色脱胶、超临界萃取、石油醚萃取,对DPPH自由基清除率从高到低依次为石油醚萃取、超临界萃取、超临界萃取后脱色脱胶;超临界萃取后脱色脱胶、超临界萃取、石油醚萃取3种工艺制备的辣椒籽油对超氧阴离子自由基的IC_(50)分别为0.09,0.13,0.34mg/mL,对羟基自由基的IC_(50)分别为0.98,1.73,2.19 mg/mL,对DPPH自由基的IC_(50)分别为38.47,10.82,2.00 mg/mL;综合比较,采用超临界CO_2萃取后脱色脱胶制备的辣椒籽油体外抗氧化性最好     

Easy Method for the Approximate Quantitation of 4-Methylthio-3-Butenyl Isothiocyanate of Daikon (Raphanus sativus L.)

Daikon (Japanese white radish, Raphanus sativus L.) is widely consumed across Japan. The characteristic pungent flavor of daikon is derived from 4-methylthio-3-butenyl isothiocyanate. Herein, we propose an easy method for the approximate quantitation of this compound. This method does not require an expensive analytical apparatus such as a high-performance liquid chromatograph but only an ultra violet-visible spectrophotometer to measure the absorbance of a daikon n-hexane extract, at 231 nm, against a standard. The estimation of the concentration of 4-methylthio-3-butenyl isothiocyanate by this method can sort the pungency of daikon, because this isothiocyanate is a principal isothiocyanate of daikon.     

Effect of Gamma-irradiation on Color, Pungency, and Volatiles of Korean Red Pepper Powder

ABSTRACT: Effect of gamma-irradiation on color, pungency, and volatiles of Korean red pepper powder ( Capsicum annuum L.) was investigated. Red pepper powder, vacuum-packaged in a polyethylene/polypropylene bag, was gamma-irradiated up to 7 kGy. An irradiation dose of 7 kGy reduced the population of mesophilic bacteria and fungi effectively without affecting major quality factors. Pungency of irradiated red pepper powder was not changed based on the amount of capsanoids by high-performance liquid chromatography (HPLC) and the Scoville sensory score. The red color of irradiated pepper powder was not significantly different from that of the control, judged from the capsanthin content by HPLC and color assessment using spectrophotpmetric (American Spice Trade Assn. units) and colorimetric measurements (Hunter a values). Further, the sensory evaluation showed no significant difference in pungent odor and off-odor between nonirradiated control and irradiated red pepper powder. However, when headspace volatiles of gamma-irradiated red pepper powder were evaluated by gas chromatography/ mass spectrometry with solid-phase microextraction and electronic nose with metal oxide sensors, the profiles of odor were classified into irradiated dose levels of 0, 3, 5, and 7 kGy by principal component analysis and multivariate analysis of variance. Such a difference of odor might result from the disappearance of some volatiles, such as hexanoic acid and tetramethyl-pyrazine, and the appearance of 1,3-di-tert-butylbenzene during irradiation. Moreover, it appears that the irradiation of packaging material induced a formation of 1,3-di-tertbutylbenzene, which migrated into the red pepper powder.     

4种龙眼核提取物的总黄酮含量、体外抗菌活性与抗氧化活性

以聚酰胺吸附-硝酸铝显色法测定龙眼核水提取物、95%乙醇提取物、丙酮提取物、乙酸乙酯提取物等4种不同极性提取物的总黄酮含量,同时采用管碟法、最小抑菌浓度(MIC)法测定比较4种提取物的抗菌活性,并测定评价在二苯代苦肼自由基(DPPH自由基)体系、羟自由基体系、超氧阴离子自由基体系及抗脂质体过氧化体系中各提取物的抗氧化活性。结果表明：95%乙醇提取物的总黄酮含量最高,为(3.90±0.12)%,其抗菌活性也强于其他3种提取物,在质量浓度100mg/mL时,对大肠杆菌、普通变形杆菌、枯草芽孢杆菌、藤黄八叠球菌、金黄色葡萄球菌、白菜软腐菌、甘蓝黑腐菌7种菌的抑菌圈直径均达15mm以上,对各菌的MIC均≤100mg/mL;在不同的自由基体系中,4种提取物均对超氧阴离子自由基的清除作用相对较弱,但对清除DPPH自由基、清除羟自由基、抗脂质体过氧化均表现出较强的效果;以清除率达50%时所对应的样液质量浓度IC50作为指标比较发现4种提取物对3种自由基的的抗氧化作用由强到弱依次是水提取物、95%乙醇提取物、丙酮提取物、乙酸乙酯提取物,其中水提取物对这3种自由基的IC50分别为0.20、0.15、2.69mg/mL。可见,龙眼核的95%乙醇提取物适宜作为植物源抗菌剂,水提取物则适宜作为植物源抗氧化剂以深度开发利用。