Paprika powder is one of the most important spices surpassed by only the original pepper. Seventy per cent of the spice is used for industrial purposes, and in meat products, soups, sauces and snacks. The traditional quality attributes are taste, pungency, colour intensity and stability. Due to increasing safety requirements in food processing techniques, additional attributes like microbial status and the possible occurrence of mycotoxins are gaining importance. The modern strategies in agricultural and food technological production are guided by the “field to fork”, idea. Therefore, considerations about paprika quality have to be extended to include horticultural aspects.
The genus Capsicum belongs to the Solanaceae and comprises five domesticated species: C. annuum, C. frutescens, C. chinense, C. baccatum and C. pubescens. However, only members of the first three species are of industrial significance. The main distinctive features of the genus are the size of the fruits, the thickness of the fruit flesh, shape, colour and the pungency.
Capsicum fruits are known by a considerable number of names, such as Capsicums, peppers, Spanish pepper, Cayenne pepper, chile, chillies and paprika. All names, including the term “pepper“, are misleading since Capsicum is not related to the true pepper, which belongs to the Piperaceae family. The common name “red pepper” is especially erroneous since it stands for the fruits of Schinus molle and Schinus terebinthifolius, which belong to the Anacardiaceae family.
Depending on its primary uses, peppers can be subdivided into vegetable and spice Capsicums. However, both types hold more or less pungent members. Pungency is caused by capsaicinoids, which constitute a class of plant alkaloids, which are all fatty acid amides of vanillylamine. The major components are capsaicin, dihydrocapsaicin and nordihydrocapsaicin, accompanied by several minor capsaicinoids which are present at very low levels and which are not thought to contribute greatly to overall pungency. Vegetable Capsicums range from the sweet, mostly large sized and thick fleshed, green, yellow, red or black coloured varieties, like garden or bell peppers, to the large, thin walled and hot green fruits. Spice Capsicums range from the sweet non-pungent or slightly pungent varieties, designated as paprika, to the hot species, usually designated as chillies or cayenne pepper. All varieties mentioned belong to the genus C. annuum and they all evolve naturally or through cultivation and hybridization from the bird pepper C. annuum var. aviculare.
The fiery hot chillies, however, belong for the most part to the species C. frutescens and they contain almost twice as much capsaicin as the hottest fruits of the C. annuum species. The best known member of this species is C. frutescens var. tabasco, which is used for the production of the famous Tabasco sauce™ in Louisiana. Chile habanero, which belongs to C. chinense, is said to be the hottest Capsicum variety known in the world.
Table Industrial uses of Capsicum fruits and obtained products
|Treatment||Capsicums used||Produce examples|
|Fresh selling||all kinds|
|Canned (normally acidified with citric or fumaric acid)||C. annuum||Peeled pimientos|
|Frozen||C. annuum||Components of convenience food|
|Brined or pickled (with salt and vinegar)||C. annuum||Pepperoncini|
|Tomato shaped pepper|
|Lactic acid fermented||C. annuum||Tomato shaped pepper|
|Fermented for sauces||C. annuum, C. frutescens,||Sambal oelek|
|Dehydrated||C. annuum||Paprika powder|
|C. annuum, C. frutescens, C. chinense, C. baccatum||Chilli powder|
|Extracted||C. annuum, C. frutescens, C. chinense||Paprika and chilli oleoresins|
Capsicum fruits are widely used by the food industry in order to produce an extensive range of food. It will be clear from Table Industrial uses of Capsicum fruits and obtained products that raw materials used for different purposes have to fulfil different requirements defined by the processing industry. It is the aim of this chapter to discuss the special requirements for Capsicums used for the production of paprika powder.
Paprika and chilli
Dehydrated and ground Capsicum fruits represent one of the most outstanding spice commodities in the world. In fact, paprika powder is the most important spice but one, surpassed only by the original pepper, Piper nigrum. The world supply is estimated at approximately 60,000 tons per annum, with an additional 1,400 tons of paprika oleoresin. Seventy per cent of paprika powder is used for industrial purposes, whereas the rest is used domestically.
The designation of dehydrated ground Capsicum products is not quite clear, neither in scientific literature nor in cookbooks. In the US, as well as in international trade, any dehydrated, non-pungent, red pepper powder is termed “paprika” (). In Europe, however, paprika represents a more or less red spice with a typical fruity taste and a degree of pungency which ranges between “free from pungency” or “scarcely pungent” and “pungent” according to the ISO 7540 standard (). The most comprehensive paprika range is offered by Hungary, where the spice is classified into eight classes starting with “very mild” and ending with “very hot” ().
From Table Specifications of paprika and chilli within some European national regulations it can be seen that in some European countries the distinction between paprika and chillies is defined by the Capsicum species used. Whereas paprika is normally produced from C. annuum varieties, chilli is at first manufactured from C. frutescens varieties.
Table Specifications of paprika and chilli within some European national regulations
|ISO 7540 and ISO 7543-2||Capsicum annuum||Normally Capsicum frutescens|
|Codex Alimentarius Austriacus (Austria)||Capsicum annuum||Capsicum frutescens, C. chinense, C. baccatum, C. annuum|
|Schweizerisches Lebensmittelbuch (Switzerland)||Capsicum annuum||Capsicum frutescens|
|Leitsatze des Deutschen Lebensmittelbuches (Germany)||Capsicum annuum and other Capsicum species||Capsicum frutescens and other Capsicum species|
Since there is no botanical reason for making a distinction between paprika and chilli, it is good practice to differentiate according to consumer expectation. From this view, however, the essential parameter is the degree of pungency: while paprika is a fruity tasting, more or less intensive red coloured, sweet, slightly pungent or very pungent spice powder, chillies are known to be extremely hot. The aroma of chilli powder is also characteristic, however, it is normally not considered important by the consumers in the western world. So it is proposed to modify the different regulations in a way that paprika, as well as chilli powder, may contain all kinds of Capsicum fruits and that the distinction between these products is only a question of their degree of pungency. According to Bosland and Votava (), in the US dried red pepper powders are classified into five groups based on pungency level:
|Non-pungent or paprika:||0-700 Scoville Heat Units|
|Mildly pungent:||700-3,000 Scoville Heat Units|
|Moderately pungent:||3,000-25,000 Scoville Heat Units|
|Highly pungent:||25,000-70,000 Scoville Heat Units|
|Very highly pungent:||> 80,000 Scoville Heat Units|
Scoville Heat Units are estimated by sensorial tests; 15 million Scoville Heat Units are set as 100% capsaicin.
General quality criteria for paprika powder
Despite a long and comprehensive tradition in paprika production, many countries lack the necessary consistency in the application of quality-oriented cultivation and adequate processing to satisfy the quality demands, especially of, the US and Germany, the two major paprika importing countries in the world.
From a general point of view the quality attributes demanded of a foodstuff are, among other things, deduced from its intended purpose. Paprika powder is a spice, which is used for its flavouring and appetizing, as well as for its colouring and colour-stabilizing properties. Among its most important applications are sausages and other meat products, soups and sauces, broiled chicken and snacks.
The most important analytical parameters of paprika, as well as its official analytical methods. The required sensory properties of paprika powder may be articulated as follows:
- Fresh, fruity pleasantly aromatic smell.
- Pleasantly fruity-sweetish, aromatic flavour.
- According to the European view and the desired purpose it should be free from pungency, slightly pungent or very pungent.
- Whereas a light bitterness is a typical characteristic even for sweet paprika varieties, paprika powder should not comprise a dominantly bitter taste. The origin of the bitter taste is not quite clear and further research is needed.
- Free from off-flavours and off-odours which may be caused by the use of unsuitable raw material, by technological mistakes during processing, especially during drying, by unsuitable storage conditions, or by oxidative reactions during storage leading to a more or less pronounced rancidity.
- Intensely typical red colour, which remains stable over the shelf life.
Colour of paprika powder
The paprika powder available on the market ranges in colour from a bright rich red to a brick-red or orange-red, depending upon variety and quality. For industrial purposes rich red paprika powders that retain their colour as a ground product, are required.
The colour of paprika is composed of more than 30 different yellow, orange and red carotenoids. Antheraxanthin, β-carotene, β-cryptoxanthin, lutein, violaxanthin and zeaxanthin are the most common yellow to orange pigments, whereas capsanthin, capsorubin and cryptocapsin represent the most important red pigments.
During storage the carotenoids can be destroyed by autoxidative and oxidative attack. According to the present knowledge, the degree of pigment losses depends upon paprika variety, climatic conditions during ripening, provenance, timing of harvesting, post-harvest treatment, processing and storage conditions. The most significant factors influencing the colour stability are moisture content, temperature, light and oxygen.
From practical experience it is known that the amount of pigments in the freshly harvested fruits is not a good indication of the storage stability and the retention of the red colour. Therefore, it is necessary to breed and evaluate for both initial colour and colour retention properties (). In order to minimize the risk of a colour shift during storage from red to orange, the share of red pigments in the total colourant content should be as high as possible, whereas the share of yellow pigments should be as low as possible.
Biacs et al. () described that the colour stability of paprika is influenced by the amount of esterified pigments and by the capsanthin/capsorubin ratio. The authors stated that varieties with a high amount of fatty acid di- and monoesters of capsanthin and capsorubin exhibit a better storage stability than varieties with a high amount of free pigments. In addition, the storability should be improved by a high capsanthin/capsorubin ratio. Since capsanthin contains fewer polar groups on its structure than capsorubin, it should be more stable against oxidative degradation.
Several investigations have shown that the oxidation of carotenoids in paprika is influenced by the water activity to such an extent that the available water slows down the oxidation process (). According to Osuna-Garcia and Wall (), for arid regions, a 15% pre-storage moisture content level may reduce the colour loss of stored ground products by at least 50%. However, from a microbiological point of view, such high moisture contents cannot be accepted as the risk of bacteria and mould will increase under these conditions.
Carvajal et al. () reported that an important colour stabilizing effect can be observed from naturally available or added antioxidants like ascorbic acid and/or α-tocopherol. Another useful substance is ethoxyquin (6-ethoxy-l,2-dihydro-2,2,4-trimethylquinoline), which is permitted in the US for stabilizing the colour. In addition to its antioxidative power, ethoxyquin can be used as a fungicide. For that reason in some countries the substance is classified and permitted as a plant protecting agent which is not allowed to be used as an antioxidant in food. In Germany the residues of ethoxyquin are limited by law to a maximum value of 0.01 mg/kg fresh paprika or 0.1 mg/kg paprika powder.
In order to optimize the colour retention, along the processing line, special attention has to be paid to the drying process. Tevini () reported that the drying conditions within belt-dryers often are not optimized. As a result, the paprika fruits are overheated, creating the conditions for subsequent non-enzymatic browning or the Maillard reaction which leads to brownish discolourations of the ground product.
In this respect two further requirements on paprika varieties for industrial use should be mentioned: the fruits should be thin-fleshed and should have the highest possible dry matter content in order to facilitate drying and to reduce thermal strain. Moreover, as the availability of free reducing sugars is one of the preconditions for the Maillard reaction, the content of reducing sugars in the fresh paprika fruits should be as low as possible.
In general, food safety is of increasing importance all over the world and therefore it is necessary to summarize the hygienic demands on paprika powder in detail:
- Paprika powder has to be free from toxic or hazardous substances.
- Paprika powder has to be free from living insects or larvae.
- Paprika powder has to be practically free from dead insects and insect fragments.
- Paprika powder has to be practically free from rodent contaminations.
- Paprika powder has to be free from extraneous matter, which includes all vegetable matter other than fruits of Capsicum, as well as colouring agents, oils or other products added to improve the quality or to mask defects.
- Paprika powder should meet the microbial values summarized in Table Microbial approximative and warning values for spices which should be given to the consumer or which should be used in foods without any further germ reduction treatment (concerning Salmonella see “Bacteriological problems”).
- Paprika powder should be free from mycotoxins (for details see “Mycotoxins”).
- Paprika powder should not exceed the maximum values set up for residues of plant protecting substances prescribed in the legal regulations of different countries.
Table Microbial approximative and warning values for spices which should be given to the consumer or which should be used in foods without any further germ reduction treatment
|Organism||Approximative value (cfu/g)||Warning value (cfu/g)|
|Salmonella||__||not detectable in 25 g|
|Staphylococcus aureus||1.0 x 102||1.0 X 103|
|Bacillus cereus||1.0 x 104||1.0 X 105|
|Escherichia coli||1.0 x 104||—|
|Sulphite reducing Clostridia||1.0 x 104||1.0 x 103|
|Moulds||1.0 x 105||1.0 x 106|
It should be mentioned that in Germany the amount of ethylene oxide and 2-chioro-ethanoi in paprika powder is limited to 0.1 mg/kg. Formerly, fumigation with ethylene oxide was used as a method for the degermination of spices. However, the application has been prohibited due to the formation of toxic ethylene chiorohydrin (2-chloro-ethanol). However, sometimes small amounts of 2-chloro-ethanol is found in paprika powder that has not been fumigated, raising the question whether ethylene oxide is produced as a natural metabolite of the paprika fruits.
There are two particular concerns of hygenic safety: the microbial contamination of spices, in particular the occurrence of salmonella, and the frequently observed interior mouidiness that poses an inherent risk of mycotoxin formation. Paprika, as well as other spices, are natural products, which contain microbial flora. Since a significant volume of spice is sold without any germ reduction, the microbial status of the product is of outstanding importance.
Among the pathogenous microorganisms which might be available in paprika powder, special attention has to be paid to the Enterobacteriaceae. Due to a salmonella outbreak in Germany in 1993 caused by paprika-seasoned potato chips (), and the perception that salmonella strains exist that are capable of changing their virulence due to the occurrence of plasmids or prophages, it must be assumed that under certain conditions one single salmonella may be infective and that any detection of salmonella must be rated as a serious health risk. Based on this knowledge it was decided by the authorities that salmonella should not be detectable in 25 g of paprika or chilli powder.
From a qualitative point of view, irradiation with ionizing beams constitutes the only really acceptable means for the degermination of paprika. Since 1999 the irradiation of spices and aromatic herbs has been permitted within the European Community, however, consumers in several countries still do not accept this procedure. What consequences these facts may have on the paprika market need not be discussed here in greater detail.
The data, which can be used as a guideline for the microbiological assessment of spices, are summarized in Table Microbial approximative and warning values for spices which should be given to the consumer or which should be used in foods without any further germ reduction treatment. Again, it can be seen that salmonella should not be detectable in 25 g of the spice.
Another important problem with paprika and chilli powder is the subject of interior mould growth. The topic is doubly problematic as, in many countries mouldy foodstuffs are considered unpalatable, regardless of the sanitary risk they present, and second, the presence of moulds always implies the risk of mycotoxin formation. El-Dessouki () analysed 15 samples of paprika and 24 samples of chilli powder for aflatoxins. Seven of the paprika samples contained aflatoxin B1 and B2 and up to 15.3 µg total aflatoxins per kg sample. Thirteen of the chilli samples contained aflatoxin B1; B2 and G1 contained up to 218.4 µg total aflatoxins per kg sample. According to the German legislation, the so-called Aflatoxin-Verordnung, the aflatoxin content is restricted to 2 µg aflatoxin B1 per kg and 4 µg total aflatoxin per kg foodstuff. These values have currently been raised by the European Community for several spices including paprika and chilli to 5 µg aflatoxin B1 and 10µg total aflatoxin per kg foodstuff (EC Regulations No 472/2002). Bassen and Brunn () analysed ten random samples of paprika for ochratoxin A residues. Only one sample was negative, the others possessed ochratoxin A in quantities between 0.5 and 8.6 µg/kg.
Against this background it is more and more important to install GAP- and HACCP-systems in the cultivation and processing lines in order to control the microbial risks for all kinds of Capsicum products. One of the requirements for paprika fruits is that the mechanical handling should be sufficient to ensure that the fruits are not damaged during harvesting or storage so as to prevent infection, e.g. with moulds.
Modern strategies in agricultural and food production technologies ensure a complete line from the production of the paprika fruits to the dried and ground paprika powder on the table of the consumers. In order to exploit the modern technological possibilities in an optimal way it is necessary to find a common level of communication between breeders, farmers and food technologists. For this reason the discussion of actual requirements on paprika powder for food processing should be completed with a summary of properties, which should be fulfilled by an optimal paprika variety.
- The growth period of the variety should be as short as possible so as to ensure that the fruits will thoroughly ripen on the plant before the cold season starts (e.g. in Hungary).
- In order to ensure an even maturation, the individual fruits should develop as uniformly as possible. The decision whether a fruit may be picked is to be made by the harvester in accordance with the degree of colouration. From a hygienic point of view mechanical harvesting is preferred.
- The fruits should not be prone to interior mould growth so as to prevent the occurrence of mycotoxins. It will be an interesting field of research to look at whether the comprehensive gene pool of Capsicum comprises natural activities against internal mould growing or not.
- Plants should be robust and have a solid stem to prevent fruits from coming into contact with the ground. The direct or indirect contact (splash water during rainfall or irrigation) of the fruits with the ground or with soil particles is one of the routes of microbial contamination.
- Maximization of hectare yields with regard to ASTA (colour) values.
- Resistance to insects and plant diseases.
- Resistance to plant-protective agents.
- Growing with equally good results in geographically differing regions. Recently it was discussed whether organizing paprika cultivation in climatically differing regions was possible so as to provide the market with new paprika every four to six months. Presupposing a defined and constant quality standard, this provision could be the basis on which to minimize the necessary storage periods between harvesting and processing.
It should be clear that the partnership between breeders, farmers, food technologists, salesmen and customers has to be established on a higher level than it has been in the past. The requirements can only be met by operations and procedures which are accepted by the consumers in different countries. However, concerning the discussed context, irradiation and genetic engineering are two important methods which are not currently accepted by consumers in many countries.
Selections from the book: “Capsicum. The genus Capsicum”. Edited by Amit Krishna De. Series: “Medicinal and Aromatic Plants — Industrial Profiles”. 2003.