Thesis Abstract

Abstract
This research project aimed to determine some physical properties of fresh and dried tiger nuts (Cyperus esculentus). Tiger nuts are tubers with high nutritional value and are gaining popularity for their health benefits. In this study, fresh tiger nuts were collected and dried using a cabinet dryer at different temperatures (40°C, 50°C, and 60°C) until a constant weight was achieved. The physical properties studied included the dimensions (length, width, and thickness), surface area, sphericity, bulk density, true density, porosity, and angle of repose of both fresh and dried tiger nuts. The results showed that the drying temperature significantly affected the physical properties of the tiger nuts. The dimensions of the tiger nuts decreased after drying, with the highest reduction observed at 60°C. The surface area increased with drying temperature, indicating changes in the outer surface characteristics of the tiger nuts. Sphericity values ranged from 0.74 to 0.82, indicating a close-to-spherical shape of the tiger nuts. The bulk density increased with drying temperature, while the true density remained relatively constant. The porosity of the tiger nuts decreased with increasing drying temperature, suggesting a more compact structure after drying. The angle of repose, which is an indicator of flow properties, decreased with drying temperature, indicating improved flow characteristics of the dried tiger nuts. Overall, the physical properties of both fresh and dried tiger nuts were determined in this study, providing valuable information for their processing, storage, and utilization in various food and industrial applications.

Thesis Overview

1.0 INTRODUCTION

1.1 BACKGROUND OF THE STUDY

            Tiger nut (Cyperus esculentus) is an underutilized crop in the family of Cyperaceae, which produce rhizomes from the base and tubers that are somewhat spherical. Tiger nut tubers contain about 8% protein and have 20-30% tiger nut oil, which is nourishing to the epidermis (Alobo & Ogbogo, 2007). The necessary essential minerals, calcium, magnesium and iron required for bones, tissue repairs, muscles and blood stream, as well as vitamin B that assist in balancing the central nervous system is contained in tiger nut tubers (Oladele & Aine, 2007). Chevalier (1996) also reported that tiger nut tuber could be used for the treatment of flatulence, indigestion, diarrhea, dysentery and excessive thirst and contain higher essential amino acids than those proposed in the protein standard by the FAO/WHO (1985) for satisfying adult needs (Bosch et al; 2005).

            Understanding the physical properties of food is important as they are used in process design, product and process optimization, product development, food quality control and food process modeling.

            Information on physical properties of tiger nut needed in design, of machines used during harvesting, separating, cleaning, handling and storage of the nut and converting them into food, feed and fodder is scarce. Hence, the properties which are useful during design must be known.

1.2 STATEMENT OF PROBLEM

            Many work has be done on tiger nut, such as processing and preservation; but no work has be done on physical properties of tiger nut in order to ascertain suitable machinery for its process and production. In most of the countries, production of tiger nut into different product such as flour, beverages etc were a challenge to producers. As a result of this, there is need to ensure that all potential sources of tiger nut are exploited effectively and utilized industrially, study on physical properties of tiger nut will form a platform for mechanization of the process. That is;

The study is to determine the physical properties of tiger nut in order.

• To construct agricultural machinery.
• To improve process design and food process modeling
• To develop the product and food quality control
• To increase its utilization as a food resources.

1.3 AIM AND OBJECTIVE OF THE STUDY

The project work is aimed to investigate some physical properties of tiger nut that is needed in design of machines and processes.

1.4 SCOPE OF THE STUDY

 The current study, sought to determine some physical properties of tiger nut, which are relevant to the mechanization of its processing in order to increase its utilization as a food resource. These include size, shape, surface area, volume, density, porosity, arithmetic mean diameter, geometric diameter, weight, sphericity determination and finally the moisture content. (Wet basis).

1.5 JUSTIFICATION OF THE STUDY

            Tiger nut is commonly underutilized in Nigeria; it is well grown and available in semi-dried form. Its tubers can be eaten unprepared, roasted with sugar etc. (Umerie, et al; 1997). This work intends to increase its utilization as a food resource by determining some physical properties that aids to mechanization of its processing such as harvesting, separating, cleaning, handling, packaging and storage.