Capsicum--production, technology, chemistry, and quality--Part II. Processed products, standards, world production and trade

Capsicums, as a spice, have been known since the beginning of civilization and historically associated with the discovery of the New World. The genus Capsicum (Fam. Solanaceae) provides many varieties and adds color, pungency, and aroma to the cuisines of most of the world. From the pungent chilli, of interest also to pharmaceuticals, to the colorful paprika and the bell capsicums with its remarkable aroma, the genus has been of great interest for its chemistry and physiological action. Pungency as a sensory attribute, its evaluation, structure-activity relationship, and its increasing acceptance and preference by diverse populations of the world are of great interest to many research disciplines. In a comprehensive review of all aspects in four sequential parts, Part I deals with History, Botany, Cultivation, and Primary Processing (CRC Critical Review, Food Science and Nutrition). The Capsicums among the spices are second only to black pepper in trades both in volume and value. The production of the different forms of this spice as ground, specialty seasonings, and as the concentrated oleoresins through technologically advanced processes, proposed newer products, the standard to control quality of the different products, world production, trade, and prospects are reviewed in detail in this, Part II.     

Capsicum--production, technology, chemistry, and quality. Part III. Chemistry of the color, aroma, and pungency stimuli

The spice capsicum, the fruits of the genus Capsicum (Family Solanaceae), is a very popular food additive in many parts of the world, valued for the important sensory attributes of color, pungency, and aroma. A large number of varieties are widely cultivated and traded. The characteristic carotenoids of the bright red paprika and cayenne-type chillies, the high character impact aroma stimuli, the methoxy pyrazine of green bell capsicum, the esters of ripe tabasco and the highly potent pungency stimuli, and the capsaicinoids of African and other Asian varieties of chillies, have been of great interest to chemists and biochemists. Research workers in other disciplines such as genetics and breeding, agriculture, and technology have been interested in this spice to develop new varieties with combinations of different optimal levels of the stimuli for the sensory attributes and to maximize production of storable products for specific end uses. Physiologists have been intensely studying the action of the highly potent pungency stimuli and social psychologists the curious aspect of growing acceptance and preference for the initially unacceptable pungency sensation. In the sequential review of all these aspects of the fruit spice Capsicum, the earlier two parts covered history, botany, cultivation and primary processing, and processed products, standards, world production, and trade. In Part III, the chemistry, the compositional variations, synthesis and biosynthesis of the functional components, the carotenoids, the volatiles, and the capsaicinoids are comprehensively reviewed.     

Capsicum--production, technology, chemistry, and quality. Part IV. Evaluation of quality

Capsicum fruits are popular worldwide and are used in the cuisines of both the developing and the developed countries. With its different varieties, forms, and uses, the spice capsicum contributes to the entire gamut of sensory experience--color as finely ground paprika powder or extract in sausages, goulash, cheese, and snacks; both pungency and color as the many varieties of chillies used in Mexican, African, Indian, and southeast Asian cuisines; color, aroma, and mild pungency as the fresh green chillies used in many of the growing countries; and appearance, color, aroma, and texture as fresh fruit in salads and as a pickled and canned product. In three earlier parts in this series, the varieties, cultivation, and primary processing; the processed products, world production, and trade; and the chemistry of the color, aroma, and pungency stimuli have been reviewed. In this part, the evaluation of quality through instrumental determination of the causal components and the sensory evaluation of color, aroma, and pungency are discussed. Several methods for quantitative determination of the stimuli and the sensory evaluation of the responses to the stimuli are reviewed. The problems of sensory evaluation of color, aroma, and pungency, the dominant attributes for validation of the instrumentally determined values for carotenoids, volatiles, or particular fractions, and total and individual capsaicinoids are specifically discussed. Summarized details of selected instrumental methods for evaluating the stimuli, which are either validated by correlation to sensorily perceived responses or to adopted standards, are given along with representative data obtained for discussing the adequacy and reliability of the methods. Pungency as a specific gustatory perception and the many methods proposed to evaluate this quality are discussed. A recommended objective procedure for obtaining reproducible values is discussed, and a method for relating different panel results is shown. With such a method, highly significant correlations have been shown between estimated total capsaicinoids and the determined pungency. The estimation of total capsaicinoids by any simple, reliable method is shown to be adequate for quality control of pungency of Capsicum fruits.     

Capsicum--production, technology, chemistry, and quality. Part V. Impact on physiology, pharmacology, nutrition, and metabolism; structure, pungency, pain, and desensitization sequences

The spice Capsicum is the fruit of the cultivated species of the genus Capsicum (family, Solanaceae), C. annuum principally, and C. frutescens L. to a lesser extent. A third variety of C. annuum var. annuum fruits, the large-sized, fleshy bell capsicum is used as a fresh vegetable and valued for its aroma, color, and crisp texture, but with no pungency. This variety is not considered in this series of reviews covering primary processing, production, international trade, chemistry, and biochemistry of functional components--the red keto carotenoids, the aromatic volatiles and the pungent capsaicinoids in Parts I to III. The valid qualitative aspects correlating the specific components of capsicum and their sensory responses are critically covered in Part IV. In this the concluding part of the series of reviews, the significant preference of the spice for initially evoking an aversive response, its potent physiological and pharmacological effects, and the aspects of structure-activity relationships of the pungent stimuli of the capsaicinoids are reviewed. The beneficial effects particularly associated with long usage by some ethnic groups and its safe consumption levels, with a critical review of the studies on the gastrointestinal tract, the cardiovascular system, the sensory system, thermoregulation, nutritional impacts, and an overview of the five series is also detailed.     

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     

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.     

Agronomic, chemical and genetic profiles of hot peppers (Capsicum annuum ssp.)

A study on morphology, productive yield, main quality parameters and genetic variability of eight landraces of hot pepper (Capsicum annuum ssp.) from Southern Italy has been performed. Morphological characters of berries and productivity values were evaluated by agronomic analyses. Chemical and genetic investigations were performed by HPLC and random amplified polymorphic DNA (RAPD)-PCR, respectively. In particular, carotenoid and capsaicinoid (pungency) contents were considered as main quality parameters of hot pepper. For the eight selected samples, genetic similarity values were calculated from the generated RAPD fragments and a dendrogram of genetic similarity was constructed. All the eight landraces exhibited characteristic RAPD patterns that allowed their characterization. Agro-morphological and chemical determinations were found to be adequate for selection, but they resulted useful only for plants grown in the same environmental conditions. RAPD application may provide a more reliable way based on DNA identification. The results of our study led to the identification of three noteworthy populations, suitable for processing, which fitted into different clusters of the dendrogram.     

NaOH treatment reduces capsaicin content and pungency of ‘Makedoniko’ pepper (Capsicum annuum L.)

Pickled peppers are preferred by certain consumer groups at reduced pungency. To investigate the reduction in pepper pungency and capsaicin content, fresh ‘Makedoniko’ hot peppers were treated with 0, 0.5 or 1% NaOH before preserved in acid brine for 60 days. Pepper physicochemical traits were monitored following NaOH treatment and during preservation. Capsaicin content was measured in the beginning and at the end of preservation, and the peppers were also tested organoleptically. Preservation in acid brine induced the typical green–yellow product colour, increased firmness and decreased the dry mass in all treatments. NaOH‐treated pepper increased phenolics, chlorophyll and antioxidant content in dry mass during preservation faster than the control. Capsaicin content was reduced by 25 or 50% following 0.5 or 1% NaOH treatment, respectively. Pepper organoleptic pungency was also decreased following 1% NaOH treatment. NaOH reduces capsaicin content and pungency of ‘Makedoniko’ pepper, with minor effects on its processed product quality.     

Comparative Study of Capsaicinoid Composition in Capsicum Peppers Grown in Brazil

Twenty different varieties of Capsicum pepper cultivars belonging to four species (Capsicum chinense, Capsicum annuum, Capsicum frutescens, and Capsicum baccatum) were characterized in terms of their capsaicinoid and total phenolic content. The peppers were sown in a farm in the southeastern region of São Paulo State. The determination of capsaicinoids was performed by ultra-performance liquid chromatography. The total phenolic content was determined spectrophotometrically with the Folin-Ciocalteu reagent. Results were expressed as µg capsaicinoid/g fresh pepper and as Scoville heat unit. A wide variation was observed among the compositions of capsaicinoids. Capsaicin and dihydrocapsaicin were the most abundant peaks. Capsaicinoids were not identified in the pepper varieties Cheiro Verde, Cambuci Verde, Cambuci Vermelha, and Biquinho. The spiciest pepper was Naga Jolokia (119,016 Scoville heat unit). Regarding the phenolic contents, a large variability was observed. Total phenolic content ranged from 0.35 mg gallic acid equivalent/g in Cambuci Verde to 3.06 mg gallic acid equivalent/g in Naga Jolokia. The current study may benefit consumers, the food, and pharmaceutical industries due to the increasing interest in pharmacological compounds present in hot and sweet Capsicum peppers.     

Isolation and Analysis of Bioactive Compounds in Capsicum Peppers

An overview of the state of the art in the extraction, isolation, and analytical determination of bioactive compounds in peppers of the genus Capsicum is presented. The review is structured by classes of phytochemicals. Both major and minor constituents of peppers are considered. Modern trends in analytical chemistry of nutrients in regard to pepper analysis with particular focus on chromatographic and related methods are discussed. Attention was paid to controversial questions of pepper analysis, including but not limited to problems of sample degradation and the completeness of extraction of target analytes. The rationale for choosing an optimal strategy of analysis is given.     

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。     

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.     

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。     

A review on conventional and biotechnological approaches in white pepper production

White pepper is the dried seeds obtained from pepper berries (Piper nigrum L.) after the removal of the pericarp. It has been widely used as seasoning and condiments in food preparation. Globally, white pepper fetches a higher price compared to black pepper due to its lighter colour, preferable milder flavour and pungency. Increasing global demand of the spice outpaced the supply as the conventional production method used is laborious, lengthy and also not very hygienic. The most common conventional method is water retting but can also include pit soil, chemical, boiling, steaming and mechanical methods. The introduction of a biotechnological approach has gained a lot of interest, as it is a more rapid, convenient and hygienic method of producing white pepper. This technique involves the application of microorganisms and/or enzymes. This review highlights both conventional and latest biotechnological processes of white pepper production. © 2018 Society of Chemical Industry     

利用PCR-DGGE技术筛选分离海南黄帝椒产品微生物

黄帝椒是海南特产高辣度辣椒。该研究以黄帝椒产品为原料,采用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)技术分析了其微生物种群关系,并结合传统平板筛选法进行菌种分离及鉴定,获得了海南特辣黄帝椒产品优势微生物。研究结果显示,海南黄帝椒产品平板筛选分离到了Pseudomonas stutzeri,Lactobacillus plantarum,Lactobacillus brevis等可培养的菌株;DGGE图谱中检测到了6个条带,其中,乳酸菌占总菌数的65%,处于最优势地位,假单胞菌占总菌数的16%,处于次要地位。该研究也首次提及了不同的微生物对黄帝椒产品的颜色、脆性的影响。     

Piperine—The Bioactive Compound of Black Pepper: From Isolation to Medicinal Formulations

Piperine is the major bio‐active component of pepper, which imparts pungency and biting taste to it. This naturally occurring alkaloid has numerous demonstrated health effects and beneficial therapeutic properties; nevertheless, its biological applications are limited due to its poor solubility in aqueous environments. This emphasizes an implementation of advanced extraction approaches which could enhance the extraction yield of piperine from pepper and also the development of new formulations containing piperine to improve its in vivo bioavailability. This paper presents a review on the therapeutic and medicinal effects of piperine, its isolation from pepper fruit and the development of new formulations for its medicinal (pharmaceutical) applications. A thorough review on conventional and advanced separation techniques for the extraction of piperine from pepper is presented and an outline of the most significant conditions to improve the extraction yield is provided and discussed. Different methods used to measure and quantify the isolated piperine are also reviewed. An overview of biotechnological advancements for nanoparticle formulations of piperine or its incorporation in lipid formulations, which could enhance its bioavailability, is also presented.     

Characterization of total capsaicinoids,colour and volatile compounds of Habanero chilli pepper (Capsicum chinense Jack.) cultivars grown in Yucatan

Total capsaicinoids, colour and volatile compounds of 10 Habanero chilli pepper (Capsicum chinense Jack.) cultivars grown in Yucatan, grouped by their colours: four red, five orange and one brown, were determined. The content of capsaicinoids, responsible for the pungency of chilli peppers, varied between 41.8 and 65.9 mg g⁻¹ dry fruit. Mean concentration of orange cultivars was 55.0 mg g⁻¹, while red cultivars had 45.0 mg g⁻¹ dry fruit, indicating that the first ones are more pungent. The composition of volatile compounds of the Habanero chilli peppers differs clearly for the different cultivars. Orange and brown cultivars have in general higher amounts of esters, with their fruity odour notes, than red cultivars. These differences are reflected in the amount of total volatiles, which is higher in orange and brown cultivars in comparison with red cultivars. From these results it can be concluded that orange and brown cultivars are better in terms of their flavour-relevant chemical composition than red cultivars.     

Capsaicinoids quantification in chili peppers cultivated in the state of Yucatan,Mexico

Capsaicinoids are a group of 12 or more related alkaloids responsible of the pungent sensation in fruits of the genus Capsicum. Capsaicin [(E)-N-(4-hydroxy-3-methoxybenzyl)-8-methyl-6-nonenamide] and dihydrocapsaicin are responsible for more than 90% of the pungency. This work describes the quantitative analyses by gas chromatography of the content of capsaicin and dihydrocapsaicin in the pericarp, placenta, and seeds of seven cultivars of chili peppers cultivated in the state of Yucatan, Mexico [chawa, dulce, sukurre, xcat’ik (Capsicum annuum L. var. annuum), maax (Capsicum annuum L. var. aviculare), and habanero orange and habanero white (Capsicum chinense Jacq.)]. Capsaicin content was higher, as expected, in the fruits of habanero orange and habanero white, followed by sukurre, chawa, xkat’ik, and maax. Dihydrocapsaicin content did not follow the same scheme, being higher in the fruits of sukurre, followed by chawa, habanero white, habanero orange, and maax. Xcat’ik showed minor quantities of dihydrocapsaicin, while dulce chili contained only traces of these two alkaloids.     

Ginger-chemistry, technology, and quality evaluation: part 2

Ginger is used in more ways than any other spice. This monograph, published in two parts, comprehensively reviews production, trade, processing, chemistry, and evaluation of quality. Botany, world varieties, agronomy, crop improvement, and potential are reviewed briefly with emphasis on the yield of functional components. Processing for the market, international trade patterns and factors influencing them are discussed. Derived products such as ginger powder, syruped ginger, volatile oil, and oleoresin are discussed in greater detail. The increasing world demand for quality products of added value such as the oleoresin and volatile oil show the prospects for their production in the growing countries. The chemistry of the components which contribute aroma and pungency that characterize ginger is critically reviewed. The second part deals with evaluation of quality. The physicochemical parameters prescribed as a measure of quality for ginger and its products in the existing standards, can assure only hygienic quality and purity, and possibly the source, when new parameters such as GC-finger prints are included. The importance of sensorily evaluating flavor quality is emphasized to understand the variation in flavor quality required by the industrial and retail markets. Related areas, such as problems in sensory evaluation of intense flavored substances, objective flavor profile analysis, correlation of instrumental and sensory data are discussed, and our recent work in this area is summarized. Areas where more research is needed are indicated. Other areas briefly discussed are functional, physiological, and toxicological properties in use of ginger; biosynthetic aspects of components stimulating flavor; structure and pungency and chemistry of spices from allied species and genera. A comprehensive bibliography is provided to aid in further study and research.     

Volatile compounds and capsaicinoid content of fresh hot peppers (Capsicum annuum L.) of different Calabrian varieties

BACKGROUND: Because of the great variability in size, shape, colour, pungency and aroma of Calabrian Capsicum annuum(hot pepper), this study was carried out to furnish producers with information on volatile compounds and capsaicinoid content useful for the genetic improvement of this species. Fully ripened fresh peppers of the most widely cultivated varieties were studied. Capsaicinoid content was determined by reverse phase high‐performance liquid chromatography/diode array detection (RP‐HPLC/DAD). Volatile compounds were determined by headspace solid phase microextraction/gas chromatography/mass spectrometry (HS‐SPME/GC/MS). RESULTS: Sixty‐four volatile compounds were identified, the main classes being alcohols, aldehydes, terpenes and aliphatic branched‐chain hydrocarbons. The ‘Naso di cane’ (C. annuumvar. abbreviatum) variety contained the lowest amount of volatiles, especially alcohols and aldehydes, while the highest levels of capsaicin and dihydrocapsaicin were found in ‘Vulcan’ and ‘Corno di capra’ varieties. CONCLUSION: From statistical evaluation of the data obtained, each variety showed a typical composition of capsaicinoids and volatiles determining the taste and odour of the hot peppers. These results should be useful in the context of research aimed at selecting varieties with the best sensory characteristics. Copyright © 2009 Society of Chemical Industry