Spice class

Because of the great diversity of phytochemicals in fruits, vegetables, herbs and spices, only the major structural classes in the most common food plants, have been selected for discussion (see below and Figs. 15.2 and 15.3, for example, phytochemicals). These are also the phytochemicals for which there is generally the greatest information on food composition and health effects. 

In traditional mead, small amounts of fruits, spices, and herbs are added, but their incorporation should not mask the honey flavor and aroma (McConnell and Schramm, 1995). According to method of production, mead can be classified in different ways. Pyments, cysers, melomels, and metheglin are meads that include the addition of grapes, apples, other fruits, and spices, respectively. Spiced pyment can be classed as a hippocras (McConnell and Schramm, 1995). 

There are two kinds of preservatives, class I and class II. Class I preservatives include common salt, sugar, glucose/sucrose syrup, acetic acid or vinegar, spices, and wood smoke. The addition of these to foods is not restricted. Class II preservatives include benzoic acid and its salts, nitrates and nitrites, sorbic acid and its salts, and sulfurous acid and its salts. Their addition to food is, however, restricted. 

Scratch tests with powdered commercial spices in 70 patients with positive skin tests to birch and/or mugwort pollens and celery were positive to aniseed, fennel, coriander, and cumin, all Apiaceae, in more than 24 patients (2). Spices from unrelated families (red pepper, white pepper, ginger, nutmeg, cinnamon) elicited positive immediate skin test reactions in only three of 11 patients. Specific serum IgE to spices (determined in 41 patients with a positive RAST to celery) up to class 3 was found, especially in patients with celery-mugwort or celery-birch-mugwort association. The celery-birch association pattern was linked to positive reactions (RAST classes 1,2) with spices from the Apiaceae family only. 

The other class of lipid molecnles, based on a branched five-carbon stmc-ture called isoprene, was first identified via steam distillation of plant materials. The extracts are called essential oils. They are often fragrant, and are used as medicines, spices, and perfumes. A wide variety of structures is obtained by fusing isoprene monomer units, leading to a very diverse set of compounds, including terpenes, such as j8-carotene, pinene (turpentine), and carvone (oil of spearmint) and steroids, such as testosterone, cholesterol, and estrogen. 

Plants - Lignin, tannins, and pigments, flavor components of spices (cinnamon oil, wintergreen oil, bitter almond, nutmeg, cayenne pepper, vanilla bean, clove, and ginger) are derived from coniferyl alcohol. Coniferyl alcohol, in turn, is derived from phenylalanine and tyrosine. Phenylalanine is also a precursor of plant pigments and related polyphenolic compounds called flavonoids. The biosynthetic scheme leads to a class of flavonoids called anthocyanins, which are common flower pigments.. An offshoot of this pathway leads to the synthesis of cocaine. 

Terpenes are a diverse class of lipids. More than 20,000 terpenes are known. They can be hydrocarbons, or they can contain oxygen and be alcohols, ketones, or aldehydes. Oxygen-containing terpenes are sometimes called terpenoids. Certain terpenes and terpenoids have been used as spices, perfumes, and medicines for many thousands of years. 

Thin-layer chromatography remains one of the main methods for class fractionation and speciation of lipids [23,24] and is used increasingly to determine the botanical origin, potency, and flavor potential of herbs and spices [25-27]. In the pharmaceutical industry, it is used for the analysis of complex and dirty samples with poor detection characteristics and for stability and content uniformity testing [28-31]. It continues to be widely used in the standardization of plant materials used as traditional and modem medicines. In addition, it retains an historic link with the characterization of dyes and inks and the control of impurities in industrial chemicals. 

A great deal of work has been carried out on the TLC separation of various classes of synthetic dyes on untreated plates. Dyes from various sources, namely, foodstuffs (fruits, oils spices, alcoholic products), coated tablets, leather, fibers, cosmetics, etc., are first extracted and then applied to the layers. About 200 ml of developing solvent in a chromatographic development tank is then used to develop the chromatograms up to 10 cm. The data for the di fferent developing solvents and adsorbents (stationary phases) used for the separation of a variety of synthetic dyes, along with specific characteristics of the separation procedure, if any, are tabulated in Table 1. Details of specific separations follow. 

In contrast to natural oils and water, some components found in the herbs and spices listed in the appendix to chapter 6 have quite substantial solubilities in liquid carbon dioxide, or are completely miscible with it. Some of these (for example, limonene, cinnamaldehyde, eugenol, hexanol and pinene) were studied by Francis [5], who found that limonene, hexanol and pinene were completely miscible. These are Class A (or possibly Class C) systems. They would thus be anticipated to show closed loop pressure/ composition diagrams at temperatures above the critical temperature of carbon dioxide and to become totally miscible with supercritical carbon dioxide at comparatively low pressures. 

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