Why are Farmers Hungry?
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ΠΛΗΡΟΦΟΡΊΕΣ ΣΧΕΤΙΚΆ ΜΕ ΤΟΝ ΚΑΦΕ USEFUL INFO ABOUTCOFFEE
OTA-producers in coffee What organisms are involved in the production of OTA in coffee? As noted above, certain fungi have ecological associations with certain crop plants, and some processing or storage conditions favour specific fungi - hence certain crops have a tendency to contain particular mycotoxins and not others. Coffee is no exception.Neither of the OTA-producing species of Penicillium (P. verrucosum and P. nordicum) have been isolated from coffee. P. brevicompactum is common in coffee and is in the same group as the two producing species, but is not an OTA-producer. For coffee, three species or groups of species, all in the genus Aspergillus, are of possible significance: 1. A. niger complex (there is no consensus on speciation in A. niger-like fungi) is by far the most common, particularly in Coffea caneophora (robusta), but OTA production is rare and usually feeble. One study revealed only one producer amongst the seventy isolates tested; 2. A. carbonarius is generally rare, but there is some evidence that it can be relatively common in certain locations. Most isolates seem to be capable of OTA production in significant amounts, though over a restricted range of environmental conditions; 3. A. ochraceus and related fungi are well distributed in coffee production systems and because OTA production is common (about 80% of isolates readily produce OTA), it comprises the most important OTA-producing species in coffee. OTA contamination of coffee has been shown to be primarily a post-harvest problem. Basically, adequately controlling the water available in coffee that could support mould growth and mycotoxin contamination during the post-harvest handling of coffee is the best way to avoid OTA contamination. | ||||
Mycotoxins What are they?
The moulds and mycotoxins that are considered to be of major public health and economic significance worldwide are listed in the table below:
(see FAO, Food and Nutrition Papers 73, 'Manual on the application of the HACCP system in mycotoxin prevention and control', 2001) 1 The term 'mycotoxin' combines the Greek word for fungus ('mykes') and the Latin word for poison ('toxicum'). Pitt (1996) defined mycotoxins as "...fungal metabolites which, when ingested, inhaled or absorbed through the skin cause lowered performance, sickness or death in man or animals, including birds". | ||||||||||||||||||||||||||||||||
Coffee Production and Trade Coffee botany and ecology
Arabica: Original arabica strains generally produce good liquors with acidity, and have the greatest flavour and aroma characteristics, but are susceptible to pests and diseases. Resistance is thus a major goal of plant breeding programmes1. A number of more tolerant varieties have been developed over the years, including the well known varieties 'Typica' and 'Bourbon', which are considered to be the first cultivars of arabica.
The beans, however, are of inferior taste than arabica, and have twice the caffeine content. Robusta coffee commands a lower price on the market, and is often used for soluble coffee or to give a caffeine 'boost' in espresso2. Robusta coffee is grown in West and Central Africa, throughout South-East Asia and to some extent in Brazil, where it is known as 'Conillon'. 1 Including arabica / robusta crosses which aim to improve arabica by conferring disease resistance and vigour, or to improve on the cup quality of robusta. The 'Catimor' variety is a cross between Caturra and Hibrido de Timor (a natural arabica / robusta hybrid), and is resistant to coffee leaf rust (Hemileia vastatrix). 2 The distinction between arabica and robusta coffee has become more blurred in recent years. Steam cleaning technologies can improve the quality of robusta coffee, allowing it to be substituted for arabica in some markets, notably Germany. | ||||||