Presentation on theme: "LOCUST BEAN TREE The locust bean tree is named Parkia biglobosa in honour of Mungo Park It grows tall, more than 20m tall It also provide food and tree."— Presentation transcript:
LOCUST BEAN TREE The locust bean tree is named Parkia biglobosa in honour of Mungo Park It grows tall, more than 20m tall It also provide food and tree cover
LOCUST BEAN POD The pods are large and long The seeds in the pods are its most prized possession
LOCUST BEAN SEED WITH PULP The seed is enclosed in a yellow dry powdery fruit pulp called “dorowa” in Hausa It contains more carbohydrate than the seed It is sweet to taste and is popularly consumed in rural Africa when grains stores are empty The pulp is removed by washing to reveal the seed
FERMENTED LOCUST BEAN The fermented seed is nutritious and rich in protein It is consumed as a condiment in soups and stews in fresh and dried forms
INTRODUCTION Locust bean is very rich in protein and popularly consumed as condiment in soups and stew in fresh and dried form (Omafuvbe et al 2004). Freshly prepared iru has short shelf life while drying preserves and improved the shelf life (Sanni et al 1999). However the seed is underutilised in spite of the high protein content Drying the seed may improve the utilisation and consumption This is because drying removes water, concentrates nutrient and preserve materials for further usage (Suleiman et al 2013) Little is known about the properties of the dehulled and dried unfermented seed Therefore objective of the study is to:
Objective of the work To compare the effect of different drying methods: Sun drying, Oven drying and Microwave drying On Proximate and mineral composition of the dried seed.
Materials and method Locust bean which has been removed from the pod was boiled for 16hrs until the seed is soft The softened seed coat was removed manually by scrubbing between the hands The seed coat was separated from the cotyledons by washing with water The separated cotyledons were dried to a moisture content of less than 10% using sun drying (5days at 29 O C), oven drying 3 days at 59 o C and microwave oven drying methods (15mins) Dried seed were milled and stored in air tight container for further analysis. Proximate and mineral analysis was carried out on the milled stored samples.
Table1 :Proximate composition of locust bean seeds before and after drying PARAMETERFresh dehulled unfermented cotyledon Sun dried unfermented cotyledon Oven dried unfermented cotyledon Microwave dried unfermented cotyledon Protein %18.3024.0124.2522.43 Fat %3.067.327.236.17 Fibre %1.854.944.753.30 Ash %2.815.895.804.84 Moisture %42.355.155.245.03 CHO %31.6452.7152.7458.24
Fig 1:Proximate composition of locust bean before and after drying
Table2 :Mineral composition of locust bean seed before and after drying parameterFresh dehulled unfermented cotyledon Sundried and unfermented cotyledon Oven dreid and unfermented cotyledon Microwave dried and unfermented cotyledon Na %0.0680.1070.1080.093 K %0.4300.8480.8560.705 Ca %0.1680.2360.2400.210 Mg %0.1100.2420.2540.224 P %0.2150.3400.3460.320 Fe %0.0190.0380.0440.031
Fig2 :Mineral composition of locust bean seed before and after drying
Discussion Table 1 and 2 shows the proximate and mineral content of the fresh and dried seeds Apart from increasing the shelf life of the seed, drying increased the nutrient and mineral content of the seed in all the three methods (Fig1 and Fig 2). The nutrient and mineral content is influenced by the method of drying Drying increased the protein content from 18.30% (fresh) to range of 24.01-24.25% It reduced moisture content to less than 6% in all the drying methods
Discussion cont The oven dried seeds had the highest nutrient content, while the microwave had the lowest Mineral content doubled after drying except for sodium, while potassium and iron had the highest and lowest contents respectively (Fig2) While there was no significant difference in mineral content of seed using sun and oven drying, the microwave dried seed was significantly lower in mineral content Even though the microwave had shortest drying time (15mins), other factors like heat intensity and temperature may affect protein quality
conclusion The dried seeds are nutritionally better than the fresh seed as they had better nutrient than fresh seed The higher nutrient content and low moisture content will preserve the seed and increase their utilization especially in protein deficient food formulations The drying properties of the sun dried and oven dried seeds were similar, they retained nutrients better than the microwave dried seed Sun drying and oven drying are recommended than microwave drying