| ||||
|
|
|
|
|
Coffea arabicaCoffee, Coffee pulpby Ricardo Bressani, Adviser Agricultural Sciences and Nutrition References: 573, 575 The coffee plant is a fully-branched shrub between 2 to 5 meters in height, depending on the species, with dark glossy leaves. Along the branches, groups of white fragrant star-like flowers develop. The fruit or "coffee berry" is a two-seeded unit deep-crimson when fully mature, about 1 cm in diameter. The coffee berry shows four anatomical fractions: the coffee bean proper or endosperm; the hull or endocarp; a layer of mucilage or mesocarp, and the pulp or esocarp. Because of the viscous nature of the mucilage when the berry is mature, a slight pressure applied to the berry is enough to expel the two beans from the fruit. This characteristic has been used to advantage in the process that has been practiced for a long time to separate the beans from the rest of the fruit's structural component. Coffee pulp, also identified as coffee fruit without seeds, is an abundant agricultural by-product that causes serious environmental pollution problems. It represents around 43% of the weight of the coffee fruit on a fresh weight basis, or approximately 28% (26-30%) of the coffee fruit on a dry weight basis. The other by-products of coffee fruit processing are the mucilage, about 5% (5-14%) of the dry weight of the fruit, and coffee hulls, representing 12% (10-12%) of the weight of the fruit on a dry weight basis. The coffee pulp is obtained either by subjecting the coffee fruit to a depulping operation with the help of water, or by first drying the coffee fruit, followed by a dehulling operation. The wet processing method of depulping follows the following operations: after harvest, the coffee berries are transported to the coffee processing plant, where they are dumped into a tank of water to remove spoiled, green fruits and foreign material. With the help of water, used as a transport mechanisms, the berries are taken to the pulping machines which by pressure separate the beans with the mucilage and hulls from the coffee pulp. These two fractions are then separated by running water. The beans are dumped into a tank for fermentation and further processing, while the coffee pulp is transported by water to be piled for later removal or simply allowed to ferment naturally. In some instances the pulp is thrown into rivers. The fermented pulp when dried is used sometimes as an organic fertilizer applied to the coffee trees. The dry process consists in either allowing the fruit to dry in the trees, or by harvesting fresh to dry by solar dehydration or other means. Once it is dried, the fruit is dehulled. The high water content of the pulp from the wet process causes problems in handling, transport, stability and processing. For feed applications, the pulp should be dried as quickly as possible to avoid spoilage or should be preserved by other means. The wet coffee pulp has been subjected to a drying operation with or without a partial water removal, by pressure, with or without the aid of calcium hydroxide addition. Drying has been accomplished by solar dehydration, by forced hot air-drying, or both. The product obtained is dried coffee pulp. An alternative process is ensiling with 4-6% sugar cane molasses. Although fresh coffee pulp can be directly ensilaged, better quality is obtained if moisture content is around 75%. A well-packed trench silo holds an average of 325 kg of coffee pulp per cubic metre. Other treatments include mixing with urea (10%), sodium metabisulphite (0.3-0.5%), calcium hydroxide (2%), and mixtures of inorganic acids (10% HCl + H2SO4). A different and attractive ensiling process is to mix grasses, sorghum or corn, with coffee pulp in layers of about 30 cm with or without sugar cane molasses (4-6%). The silage, whether of coffee pulp alone, or mixed with grasses, is ready to be used in about 3 weeks and if well packed, it can be preserved for up to 18 months. The silage from coffee pulp alone or mixed with other forages can be used as such, or it can be dehydrated (but this operation is not necessary). In recent years, research has been done on processing coffee pulp by solid state fermentation techniques using Aspergillus niger, with some attractive results in terms of nutritional parameters. Such pulp could be used up to 15% in poultry diets and up to 20% in swine diets. The data tables below provide information on the chemical composition and data on biological utilization of coffee pulp processed in different ways. Experimental evidence has suggested that a well processed coffee pulp can be fed up to 30% dry weight for dairy and beef cattle, up to 16% for swine, and up to 5% to poultry, in well-balanced diets, particularly with respect to protein. Although the evidence available is not conclusive, the main nutritional constraints include caffeine, having a diuretic effect, tannins and a high potassium content. On the other hand, chemical treatment, anaerobic fermentation, solid-state fermentation, and juice extraction, can reduce caffeine, tannins and potassium significantly. However, if its handling before processing is not done with care, fungi may develop, which produce toxins harmful to the animal. High levels of coffee pulp, above those indicated previously, reduce feed intake with low feed conversion efficiencies.
References573, 574, 575, 627 AbstractsPigs(474) |  | |||||||||||||