Evaluation of the Nutrient and Anti-Nutrient Properties of Different Varieties of Edible Mushroom in Enugu State, Nigeria
Edible mushroom are popular and valuable food, low in calorie and high in minerals, essential amino acids, vitamins and fiber. Edible mushroom are used as food because of their good taste, aroma and nutrients . This study was aimed at understanding the nutritional and anti-nutritional quality of various edible mushrooms that exist in Enugu state.The mushroom samples agaricus spp, pleurotus astreatus and Auricularia polytrichawere purchased from Eke agbani in Nkanu west Local Government Area of Enugu state, identified, washed, oven-dried at 105oC for 4hours, milled differently to fine powders(180 micron) with an electric grinder(mini planetary ball mill) , packaged and was labeled sample A,B and C .The samples were analyzed using standard methods. There was significant difference (P<0.05) in the moisture ,protein, fat, fiber, ash, carbohydrate, minerals, vitamins and anti-nutrient contents. Moisture contents was in the range of 8.71% – 8.97%, protein 24.79% – 28.94% fat 3.17% -2.19%, fiber 19.69%- 21.%42% ash 6.45%-7.25%, carbohydrate 36.93% – 31.43%, energy(kcal) 275 – 267kcal. Tannin 0.15% – 0.27%, phytate 0.25% – 0.17%, oxalate 0.07% – 0.09%,, alkaloids s0.03% – 0.45%, Saponin 0.11 – 0.31%. mineral contents Calcium 25.31% – 203.07%, magnesium 36.81% – 205.60%, potassium 432.07 – 894.67%, sodium 29.27% 485.37%, phosphorous 225.13% – 511.90%, iron6.87% – 22.27%, Zinc 0.98% – 17.00%, riboflavin 0.397mg – 0.107mg, niacin 3.047mg – 1.127, vitamin C 12.167mg – 7.130mg.High contents of protein and carbohydrate suggest gross energy and ability to avert malnutrition that could result from insufficient proteins in the diet of humans. The presence of crude fiber and ash is significant in aiding bowel movement and mineral in the body respectively. All the samples contained minerals which helps in maintain electrolyte balance, neuron transmission and development of strong bones and teeth, vitamins were also present which aid the body in fighting against diseases and foreign sickness found in the body. Phytochemicals were presents and they are responsible for the anti-microbial activities previously reported. It is therefore recommended that the consumption of mushroom and mushroom products should be encouraged because of its nutrient and phytochemical properties. Good manufacturing practice (GMP) and safe storage conditions should be enforced ,to reduce risks associated with mycotoxins produced by moulds.
Mushrooms are macro fungi with distinctive fruiting body, which can be hypogenous or epigeous, large enough to be seen with the naked eye and to be picked by hand Chang and Miles, (2003). Mushrooms have long been used as a valuable food source and as traditional medicines around the world, especially in Japan and China. Records of health promoting properties such as antioxidant, antimicrobial, anticancer, cholesterol lowering and immunostimulatory effects have been reported for some species of mushrooms (Anderson, 2005; Mizuno, 1999; Mau et al., 2004).
The acceptance of cultivated mushroom oyster mushroom (Pleurotusostreatus), button mushroom (Agaricus bisporus) and wood ear Auricularia polytricha) as a delicacy were well-established worldwide. These mushrooms have been used as food and food flavoring materials in soups for centuries, due to their unique and subtle flavor. They are highly appreciated for their rich aroma particularly prized for cooking throughout the world. However, wild edible mushrooms have only been traditionally eaten by a specific group of people (local people, enthusiasts and gourmets) occasionally. Diez and Alvarez, (2001).
The consumption of mushroom is increasing even in the developed world due to their good nutritional value especially as a source of proteins and trace minerals Thimmel and Kluthe, (2007).
Edible mushrooms are the fleshy and edible fruit bodies of several species of macro fungi (fungi which bear fruiting structures that are large enough to be seen with the naked eye). They can appear either below ground (hypogeous) or above ground (epigeous) where they may be picked by hand. Edibility may be defined by criteria that include absence of poisonous effects on humans and desirable taste and aroma. Edible mushrooms are consumed for their nutritional value and they are occasionally consumed for their supposed medicinal value. Mushrooms consumed by those practicing folk medicine are known as medicinal mushrooms. While hallucinogenic mushrooms (e.g. psilocybin mushrooms) are occasionally consumed for recreational or religious purposes, they can produce severe nausea and disorientation, and are therefore not commonly considered edible mushrooms. Rop O, Mlcek J and Jurikova T (2009).
Edible mushrooms include many fungal species that are either harvested wild or cultivated. Easily cultivatable and common wild mushrooms are often available in markets, and those that are more difficult to obtain (such as the prized truffle and matsutake) may be collected on a smaller scale by private gatherers. Some preparations may render certain poisonous mushrooms fit for consumption. Ammirati, J. (2009). Mushrooms of the Pacific Northwest
Before assuming that any wild mushroom is edible, it should be identified. Accurate determination and proper identification of a species is the only safe way to ensure edibility, and the only safeguard against possible accident. Some mushrooms that are edible for most people can cause allergic reactions in some individuals, and old or improperly stored specimens can cause food poisoning. Great care should therefore be taken when eating any fungus for the first time, and only small quantities should be consumed in case of individual allergies. Deadly poisonous mushrooms that are frequently confused with edible mushrooms are responsible for many fatal poisonings include several species of the Amanita genus, in particular, Amanita phalloides, the death cap. It is therefore better to eat only a few, easily recognizable species, than to experiment indiscriminately. Moreover, even species of mushrooms that normally are edible, may be dangerous, as mushrooms growing in polluted locations can accumulate pollutants such as heavy metals.
Hall and Ian R. (April 2010)
1.1 STATEMENT 0F PROBLEM
Mushroom has been known to play an important role in the quest for an optimal balancing of protein in the nutritional status in Nigeria, yet the role of the mushroom harvesters have often pay less attention to the research field.
There is basically little or no documentation on the verities of mushroom. As a result many tons of edible mushroom have been wasted over the years since there is a dearth of information on published literature on different verities of edible mushroom. The need for scientific investigation becomes apparent.
There is also a need to compare the nutritional and the anti nutritional content of mushroom to know their suitability in various dishes because the general publics pay less attention to the consumption of mushroom.
Indeed this focus is called for as they make choices on behalf of many who consumes mushroom. For raw materials, ingredient in quantity and quality as well as processing method adopted. Thus determining their attitudes, motivation and constraints to making these products available to the large patronage of the populace is an important gap in national food supply chain.
1.2 OBJECTIVES OF THE STUDY
The general objective of the study was to evaluate the nutrient and anti-nutrient properties of different varieties of edible mushroom in Enugu state, Nigeria.
SPECIFIC OBJECTIVE OF THE STUDY
The specific objectives were to:
Identify the edible mushroom varieties in Enugu State
Determine the proximate nutrient composition of different verities of edible mushrooms.
Determine the anti-nutrient composition of the samples.
Determine the micro nutrient composition of the samples.
1.3 SIGNIFICANCE OF THE STUDY
There is lack of information on the nutrient and anti-nutrient properties of mushroom. Little information also exists on edible and non-edible mushroom varieties. This study will help in understanding the nutritional quality of various edible mushrooms that exist in the Easter part of Nigeria. The study will provide adequate information on how to identify the edible mushrooms and its various use in preparing nutritious dishes.