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damage and against fuel smoke condensate-induced damage. Similar to curcumin, the active principle in turmeric, eugenol, found in cloves and sesamolinol isolated from sesame seeds are reported to produce antimutagenic effect by protecting the cell from damage to its DNA.

Chemically, most of these compounds have a common phenolic structure, which helps in the detoxification of xenobiotics. Research on mustard has also shown to have antimutagenic properties (NIN Annual Report, 1993–1994).

Epidemiological studies have shown that higher intake of allium products (e.g garlic) is associated with reduced risk of several types of cancers, especially stomach and colorectal (Fleischauer and Arab, 2001). Pungent vanilloids, especially [6]-gingerol, present in ginger (Zingiber officinale) have been found to possess potential chemopreventive activities. [6]-gingerol, a pungent phenolic compound present in ginger is also reported to be a potent inhibitor of nitrous oxide (NO) synthesis and also an effective protector against peroxynitrite-mediated damage in macrophages (Ippoushi et al., 2003). These bioactive compounds of spices exert their anticarcinogenic effect by deactivating the carcinogens or by enhancing the tissue levels of protective enzymes in the body.

G. Anti-Microbial Activity

Garlic and onions have been reported to possess anti-microbial property. The sulfur-containing compounds from these plants act against both gram positive and gram negative bacteria (Carson, 1987). The extracts of garlic and onion are known to inhibit growth of many pathogenic fungi belonging to genera Aspergillus, Candida and other species (Carson, 1987). Other spices like nutmeg, saffron, cumin, and thyme also have anti-microbial potential.

In view of the beneficial physiological effects that spices exhibit, these food adjuncts deserve to be considered as natural and necessary components of our daily nutrition beyond their role in imparting taste and flavour to our food.

2.5 Some common spices

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Central America where it grows wild. Allspice is the dried fruit of the Pimenta dioica plant. The fruit is picked when it is green and unripe and traditionally, dried in the sun. It has a warm and sweetly pungent flavour like the combination described above with peppery overtones. Volatile oils found in the plant contain eugenol, an antimicrobial agent (Riffle, 1998; Yaniv and Bacharach, 2005).

B. Anise (Pimpinella anisum)

Anise also called aniseed is a flowering plant in the family Apiaceae. Anise bears a strong family resemblance to the members of the carrot family that includes dill, fennel, coriander, cumin and caraway. Anise is native to the eastern Mediterranean region, the Levant and Egypt. Anise is a herbaceous annual plant growing to 3 ft (0.91 m) tall. The leaves at the base of the plant are long and shallowly lobed, while leaves higher on the stems are feathery pinnate, divided into numerous leaves. The flowers are white, approximately 3 mm diameter, produced in dense umbels. The fruit is an oblong dry schizocarp, usually called "aniseed". Anise is sweet and very aromatic, distinguished by its characteristic flavour. The seeds, whole or ground, are used in a wide variety of regional and ethnic confectioneries (Albert-Puleo, 1980; Philip, 1999).

C. Rosemary (Rosmarinus officinalis)

Rosemary is a woody, perennial herb with fragrant, evergreen, needle-like leaves and white, pink, purple or blue flowers, native to the Mediterranean region. It is a member of the mint family Lamiaceae. Rosemary is used as a decorative plant in gardens and has many culinary and medical uses. The leaves are used to flavour various foods like stuffings and roast meats.

Rosemary is a popular Labiatae herb with a verified potent antioxidant activity. The antioxidant activity of rosemary is mainly related to phenolic diterpenes which are considered effective free-radical scavengers (Dorman et al., 2003).

D. Cinnamon (Cinnamomum verum)

Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods. It is native only to the island of Sri Lanka but now widely grown in the South East. Cinnamon bark is one of the few spices that can be consumed directly. Its flavour is due to an aromatic essential oil that makes up 0.5% to 1% of its composition. Other chemical components of the essential oil include ethyl cinnamate, eugenol

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(found mostly in the leaves), beta-caryophyllene, linalool, and methyl chavicol. (Wondrak et al., 2010).

E. Marjoram (Origanum majorana)

Marjoram is a cold-sensitive perennial herb or undershrub with sweet pine and citrus flavours.

Marjoram is cultivated for its aromatic leaves, either green or dry, for culinary purposes. The tops are cut as the plants begin to flower and are dried slowly in the shade. It is often used in herb combinations. The flowering leaves and tops of marjoram are steam-distilled to produce an essential oil that is yellowish in color (darkening to brown as it ages). It has many chemical components, some of which are borneol, camphor and pinene. (Douglas, 2001; GRIN, 2011).

F. Turmeric (Curcuma longa)

Turmeric is a rhizomatous herbaceous perennial plant of the ginger family, Zingiberaceae. It is native to tropical South Asia and needs temperatures between 20 °C and 30 °C and a considerable amount of annual rainfall to thrive. When not used fresh, the rhizomes are boiled for several hours and then dried in hot ovens, after which they are ground into a deep orange-yellow powder commonly used as a spice in curries and other South Asian and Middle Eastern cuisine, for dyeing, and to impart color to mustard condiments. Its active ingredient is curcumin and it has a distinctly earthy, slightly bitter, slightly hot peppery flavour and a mustardy smell.

Turmeric is usually used in its dried, powdered form but it is also used in fresh form much like ginger. It has numerous uses such as fresh turmeric pickle, which contains large chunks of soft turmeric. Although most usage of turmeric is in the form of root powder, in some regions leaves of turmeric are used to wrap and cook food. This usually takes place in areas where turmeric is grown locally since the leaves used are freshly picked and this imparts a distinct flavour (Gregory et al., 2008; Chan et al., 2009).

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Allspice berry Allspice leaves

Anise leaves

Plate 7. Some spices – Allspice and Anise

www.google.picture.spices. com. Accessed 15/5/2012.

Anise seeds

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Turmeric Marjoram

Sage Rosemary

Cinnamon

Plate 8. Some spices – Turmeric, Marjoram, Sage, Rosemary and Cinnamon www.google.picture.spices.com. Accessed 15/5/2012

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Onion is a famous spice commodity grown all over the world and consumed in various forms. It is cultivated mainly as a biennial, but some types are treated as perennials. It varies in shape, size and colour, due to intensive selection during domestication and natural hybridization. The distinctive flavour of alliums has established the plant as an essential part of the cuisine of the world. It is used as immature and mature bulbs, as vegetable and spice, as well as food for poultry and non-milking cattle. Onions can be eaten raw or cooked, mild flavoured or coloured bulbs are often chosen for salad. The importance of onion lies in the flavour that it imparts to various other dishes. A common onion contains 88.6-92.8% moisture, 0.9-1.6% protein, trace-0.2% fat, 5.2-9.0% carbohydrates, 0.6% ash and 23-38cal/100/g of energy. It contains vitamins D (0.3mg/100g), C (10.0mg/100g), riboflavin (0.05mg/100g), nicotine acid (0.2mg/100g), folic acid (16.0µg/100g), biotin (0.9µg/100g) and pantothenic acid (0.14mg/100g).

Among various free amino acids which vary greatly, glutanic and orginine are abundant in onion.

The concentrations of these amino acids are higher at the centre of the bulb and decreases towards the outer scales. Onion is characterized by its distinctive flavour and pungency which is due to sulphur-containing compounds that are available in the scales of bulb (Brewster, 1994).

Intact onion cells have no odour but when cells are disrupted, the enzyme allinase is released which hydrolyses the S-alk (en)yl cysteine sulphoxides to produce pyruvate, ammonia and many volatile sulphur compounds associated with flavour and odour . The tear-producing character of onion on cutting is known as lacrimatory factor. Lacrimator is formed enzymatically during the hydrolysis of S-propenyl cysteine sulphoxide (Lancaster and Boland, 1990). Besides being used as a condiment and spice for flavouring and enriching various cuisines, onion has been known for its high medicinal properties, which include;

(a) It acts as a stimulant, diuretic and expectorant and mixed with vinegar, which is used in the case of sore throat.

(b) Essential oil from onion contains a heart stimulant, increases pulse volume and frequency of systolic pressure and coronary flow.

(c) Onion consumption lowers blood sugar, lipids and cholesterol.

(d) Fresh onion juice has antibacterial properties due to allicin disulphide and cysteine compounds and their interactions.

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(e) Anti-platelet aggregation effect in human and animal blood have also been reported due to regular consumption of onion (Baghurst et al., 1977).

H. Garlic (Allium sativum L.)

This also belongs to the genus Allium. It is a herbaceous, perennial bulbous plants with typical leek odour. It originates from Central Asia and spread to Southwest Asia and the Mediterranean region. The bulb of garlic (A. sativum) is compound in nature, consisting of numerous bulblets, so-called cloves, of different sizes, and with the whole surrounded by layers of white scale leaves. The ovoid cloves are 3-4 sided with an acute summit, narrowed into a thread like portion of fibre and the base truncate. Each clove is separately enclosed in a white scale and covered with a pinkish-white scale. Garlic contains a wealth of sulfur compound that is most important for the taste. It is allicin (diallyl disulphide oxide) which is produced enzymatically from allicin (S-2-propenyl-L-cysteine sulfoxide) (Brewster, 1994). It also contains derivatives of gamma-glutamyl cysteine in the bulb that are present in considerable amount of about 4% based on the fresh weight and they are responsible for the characteristic garlic odour. Other compounds present in small amounts are flavonoids, steroids, and triterpene saponins from the β-sitosterol or F-gitogenin type. Researches on the properties/ importance of garlic have shown that it possesses anti oxidative properties and can be used to delay/retard the onset of rancidity (Kumolu-Johnson and Ndimele, 2011).

I. Ginger (Zingiber officinale Roscoe)

Root ginger is the edible rhizome or root part of the plant Zingiber officinale that belongs to the family Zingiberaceae. It bears yellow flowers and the edible part (the rhizome) resembles knotty, almost fingerlike extensions which grow down into the ground. Ginger root has a spicy yet aromatic taste and smell. The strong taste is due to the fact that it contains a mixture of phenolic compounds and essential, yet volatile oils, such as shogaols and gingerols. Ginger root is low in calories and is cholesterol free. It is a very good source of essential vitamins and nutrients such as Vitamin B6 (Pyridoxine) and B5 (pantothenic acid) (Sue, 2010).

J. African Nutmeg (Monodora myristica)

African nutmeg is a perennial edible plant of the Annanacea family. It is a berry that grows wild in the evergreen forests of the West Africa (Burubai et al., 2009). The seeds are economically and medicinally important (Okafor, 1987). The kernel obtained from the seeds is a popular

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condiment used as a spicing agent in African dishes (Ekeanyanwu et al., 2010). The seeds are embedded in a white sweet-tasting pulp, and are most economically important part of the tree.

They are aromatic and are used, after grinding to a powder, as a condiment in food. It provides flavour resembling that of nutmeg (Myristica fragnans). They are also used as an aromatic stimulating addition to medicine and snuff (Ekeanyanwu et al., 2010). The powder can also be used as a stimulant to relieve constipation, and sprinkled on sores especially those caused by guinea worm (Burkill, 1985).

The most predominant elements in African nutmeg seeds are potassium, calcium, phosphorus and magnesium. A typical African nutmeg contain 14.7% moisture, 9.1% crude protein, 29.1%

crude oil, 458Kcal/100g crude energy, 25.9% crude fibre, 2.3% ash and an acidity level of 8.3 (Burubai et al., 2009).

K. Nutmeg (Myristica fragrans)

Nutmeg is the seed of the tree Myristica fragrans, an evergreen tree indigenous to the Banda Islands in the Moluccas (or Spice Islands) of Indonesia. It is roughly egg-shaped and about 20 to 30 mm long and 15 to 18 mm wide and weighing between 5 and 10 g when dried. Nutmeg is usually used in powdered form.

L. Cloves (Syzygium aromaticum)

The word clove is derived from ‘clou’ which means nail. It is a native of Indonesia but also grown in Zanzibar, Madagascar, India and Sri Lanka. It is an aromatic flower of a tree in the family Myrtaceae. Clove tree is an evergreen tree whose height ranges from 10-20m. The bark of the tree is gray whereas the leaves are dark green, elliptical, fragrant and shiny in appearance.

Cloves spice contains essential oil (up to 15%), whose constituents are eugenol, eugenol acetate and β-caryophyllene. 100g of ground cloves contain 0.144g water, 6.783kcal energy, 0.126g protein, 0.123g ash and 0.421 total fat/lipid.

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African nut meg with pod African nut meg without pod

Ginger root Sliced ginger

Plate 9. Some spices - African nut meg and Ginger www.google.picture.spices. com Accessed 15/5/2012

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Garlic bulbs Garlic bulbs

Whole and ground nut meg Onion bulbs

Plate 10. Some Spices – Garlic, Onion and Nut meg www.google.picture.spices. com Accessed 15/5/2012

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It is also rich in potassium (23.142mg), calcium (13.566mg), magnesium (5.544mg) and sodium (5.103mg) (Chinese herbal medicine, 2004). Eugenol has pronounced antiseptic and anaesthetic properties. Cloves, apart from being used for food flavouring, confectionery and aroma in variety cuisines, natural clove is also used in other industries for its medicinal and therapeutic values.

M. Curry leaf (Murraya Koenigii)

The curry leaf tree is indigenous to India and grows almost everywhere, barring the high altitudes of the Himalayas. The leaves of the curry plant are used as a flavouring ingredient or spice in cookery. The plant is an aromatic deciduous herb, which reaches a height of 5-6 meters and the trunk has a diameter of 40-cm. The tree has elongated roots and the leaves are oval or pinnate-shaped, normally about 2.5 cm (1 in) in length. The tree has small, aromatic, blossoms and shiny, dark berry-like fruits with poisonous seeds. Curry leaf imparts a distinct aroma and a tangy flavour to the food.

N. Thyme (Thymus vulgaris)

Thyme is used as fresh and dried herb in various cuisines due to its distinct aroma. This herb is available in many varieties such as lemon thyme and caraway thyme. The extract obtained is used in aromatherapy for its therapeutic and medicinal uses. Thyme extract is known for its antispasmodic, antiseptic, aromatic, anti-inflammatory and carminative properties.

O. Peppercorn (Piper nigrum)

Pepper comes from several species of a vinous plant. Fruit, called peppercorns, is the part used for spice. Peppercorns ground for use on the table and in cooking originally only came from India, but is now also cultivated in Indonesia, Malaysia, China, Sri Lanka, Madagascar and South America. The bush has a round and smooth jointed stem; dark green leaves which are smooth, broad, and have seven nerves in them; and small white flowers. The flowers become the berries which are harvested. From this bush, three types of peppercorn are harvested: black, green, and white. The differences in the peppercorns come from when the berry of the bush is harvested and how it is processed. Black pepper is the dried, unripe berry. The corns are wrinkled and spherical, about 5 mm (1/8 in) in diameter. White pepper starts out the same as the black but are allowed to ripen more fully on the vine. The outer shell is then removed by soaking the berries in water until the shells fall off, yielding a whiter, cleaner pepper. Green pepper is from the same fruit but is harvested before they mature.

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Nutritionally beneficial and medicinally positive, pepper offers a unique flavour and a variety of uses. This master spice is versatile in all forms. It offers a vibrant flavour suitable for any dish. Pepper is used daily by most people and offers health benefits along with adding its unique flavour (Hill, 2004).

P. Salt

Salt is a generic term for compounds formed of ions such as sodium, potassium and chloride (CMC, 2012). Typically, the table salt is made up of sodium and chloride and is one of the oldest spices used and is a key component to humans, animals and plants. Its flavour is unique and versatile. Historically, the main reason for the addition of salt to food was for preservation.

However, with the coming of refrigeration and other methods of food preservation, the need for salt as a preservative has decreased (He and MacGregor, 2007). Sodium levels, especially in processed foods remain high. The tastes and flavours associated with historical use of salt have come to be expected and the relatively low cost of enhancing the palatability of processed foods has become a key rationale for the use of salt in food (Van der Veer, 1985).

However, taste is not the only reason for the continued use of high levels of sodium in foods.

For some foods, sodium still plays a role in reducing the growth of pathogens that spoil products (to reduce their shelf life) by creating an inhospitable environment, thus preventing rapid spoilage (and thus extending product shelf life). In other applications, sodium levels remain high because salt plays additional functional roles, such as improving texture.

Salt ability to decrease water activity is thought to be due to the ability of sodium and chloride ions to associate with water molecules (Fennema, 1985; Potter and Hotchkiss, 1995). Adding salt to foods can also cause microbial cells to undergo osmotic shock, resulting in the loss of water from the cell and thereby causing cell death or retarded growth (Davidson, 2001).

Salt can also play a role in the development of physical properties of foods that are beneficial for processing or developing final product qualities. For instance, salt levels play an important role in controlling the stickiness of some doughs, and eases the processing of some baked goods (Hutton, 2002). The recommended salt intake varies among individuals and their genetics, but a minimum of 500 mg and a maximum of 2400 mg per day is a good daily recommendation.

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Cloves Curry leaves

Thyme leaves Red pepper

Black pepper

Plate 11. Some Spices – Cloves, Curry leaves, Thyme leaves, Red pepper and Black pepper www.google.picture.spices. com Accessed 15/5/2012

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Table 1: List of some spices and their common names

English name Scientific/*Botanical names Yoruba Hausa

Pepper Piper nigrum L. Ata Yaji

Maggi Maggi Maggi Maggi

African nutmeg Monodora myristica (Gaertn.) Dunal Epa onje Gadamia

Ginger Zingiber officinale Rosc. Ata ile Shika

Garlic Allium sativum L. Ayu Kafanua

Cloves Syzygium aromaticum (L.) Merr. et L.M. Perry

Iyere -

Curry leaf Murraya koenigii (L.) Spreng. Curry Thyme

Thyme Thymus vulgaris L. Thyme Thyme

Onions Allium cepa L. var. cepa Alubosa Alubosa

Salt Sodium chloride Iyo Gashiri

* Botanical names according to Rehm and Espig (1991)

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