Drying: herbs vegetables

The doses applied for the widely used microbial decontamination by irradiation of spices, dried herbs, and dry vegetable seasonings (see Sec. 4.9) are much higher than the disinfestation doses. Thus radiation decontamination of these commodities is more than enough to kill also any insects eventually infesting them. 

Usage The fresh or dried herb is used for seasoning soups, meat broth, vegetables, salads the ground fruits, or an extract thereof, in celery salt. 

Plant part The fresh or dried herb. The plant is native to the temperate zones of the Northern Hemisphere and cultivated in Russia, France, Germany and southern Europe. Among the cultivated forms a distinction is made between French tarragon , which must be propagated vegetatively, and the less aromatic Russian tarragon . 

Some extractions take the form of oils. Herbal oil is prepared by soaking the dried herb in olive oil or vegetable oil and heating the herb for an extended period of time. Oils promote the concentration of the therapeutic material and, if properly stored, extend the therapeutic life of the material for months. 

A detailed monograph on irradiation of dry food ingredients has been published in 1988 [98], and an updated shorter summary appeared recently [99]. A Code of Good Irradiation Practice for the Control of Pathogens and Other Microflora in Spices, Herbs, and Other Vegetable Seasonings has been issued by the International Consultative Group on Food Irradiation [100]. 

France, Hungary, Mexico, The Netherlands, Norway, South Africa, and the United States, and global production of irradiated spices has increased from about 5000 tons in 1990 to over 60,000 tons in 1997. In the United States alone, over 30,000 tons of spices, herbs, and dry vegetable seasonings were irradiated in 1997, as compared to only 4500 tons in 1993 [101]. In 1999, about 95 million pounds of these products were irradiated accounting for about 10% of their total consumption [102]. 

Parsley is a biennial herb, native to Southern Europe and Western Asia. The finely chopped leaves are used as flavouring in Central Europe, similar to the use of coriander leaves, in sauces, soups, stuffing, rissoles, minces, etc., and also sprinkled over vegetables or salads. In addition to the leaves, the stems are also dried and powdered, both as a culinary colouring and as a dye. The roots of... 

A last European protocol uses thermoluminescence (TL) irradiation results in positive ions and free electrons, which can be relatively stable in solid and dry foodstuffs. When the food is fastly heated, the recombination of ions and electrons leads to light emission (luminescence). It was later pointed out that the seat of the phenomenon is not in the vegetable material itself but in contaminating mineral particles adhering to the products. On this basis, an European protocol (EN 1788) has been approved for herbs, spices and shrimps. 

Seeds, cereal products, bread, cake and pastries, tubers and fruit generally have a low vanadium content (5-40pgkg dry matter (DM)). Mushrooms, red radish, leafy vegetables (lettuce, spinach) as well as herbs contain much higher levels of vanadium (100- 2400 pgkg- DM) (Table 27.2). 

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