ABSTRACT
The cold storage structure was modified and evaluated for the storage of fruits and vegetables at the department of agricultural and bio-environment engineering of Kwara State polytechnic, Ilorin; the cold storage structure consists of the following components; compressor, evaporator, condenser, accumulator, dryer, etc. the variable factors are temperature and relative humidity.

The cold storage structure was tested with the following fruits; watermelon, cucumber, tomatoes and apple .these samples were stored under two conditions (ambient and cold storage) for period of three days which was monitored at four hours intervals with constant supply of electricity.

Using a constant relative humidity of 85% throughout the experiment.

The result revealed and average physiological weight loss of the samples on both ambient and cold storage, which are 7.8g, 3.3g, 21.3, 10.5 for ambient samples while3.5g, 0.8, 3.8, 2.6 for cold storage sample respectively.
The cold storage structure performs satisfactorily when evaluated and it’s recommended for the storage of fruits under controlled conditions.

CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
Fruits and vegetables are of great nutritional value.

They are important sources of vitamins and minerals thus, essential components of human diet. Consequent upon this, there had been increased trade or commerce activities surrounding these commodities.

Vegetable production forms a substantial percentage about 25% of the major food crops cultivated in the tropics and so it is the source of livelihood for a considerable section of the population (Idah, 2007).
Fruits and vegetables in their fresh forms contain high percentage of water.

They are living and hence carry out their physiological function of respiration thereby absorbing and releasing gases and other materials from and to their environment.

These activities lead to their deterioration in transit and storage, which is more rapid under conditions of high temperature and humidity. As a result, heavy losses are encountered in these produce.

Fruit and vegetable are generally classified as perishable crop if not quickly preserved when harvest they shrivel wither or rot away rapidly especially under hot condition.

Highly perishable ones likes’ leafy vegetables, tomatoes asparagus etc. even in storage have a recommended refrigeration storage life of less than one week (Ndukwu, 2011).
Fruit and vegetable are fundamentally different from most other produce which is sold stored in the fresh (unfroze) state in that they are living they respires thus suitable ventilation must be provided.

During cold storage they undergo characteristic change of senescence and of ripening of fruit (Cantwell, 2001).
Storage has been developed to ensure the supply of an agriculture product to consumers with minimized quality degradation.

Orderly marketing of perishable commodities often requires some storage to balance day- to- day fluctuation between product harvest and sales or for long term storage to extend market period.

(Tripath and Bhat 2000).
Cold room storage generally tends to depict the views and ideas of a system that embarks on a continual extraction of heat from its body whose temperature is already below its surrounding temperature. Thus, refrigeration inevitably is the only means of preserving food in its original freshness. (Ugwuet al, 2012).
1.2 Problem Statement
Lack of storage facilities is one of the major challenges facing perishable produce in Nigeria and result in higher post-harvest losses.

Temperature plays an important role in post-harvest handling of perishable produce since it affect most of the enzymatic reaction in harvesting produce cause an increase in the rate of deterioration processing.

Cooling of perishable product immediately after harvest and maintain the cold chain along the supply chain is key in slowing down the deteriorative process hence there is a need to develop a cold room that will reduce deterioration of fruits and vegetable and extend their shelf life.

1.3 Aim and Objective of the Project Work
The aim of the study is to enhance good storage facilities for fruits and vegetables under a cold room storage structure in order to prolong their shelf life and retain the quality of this perishable product for a specific period of time.
The specific objectives:
(i) To modify a cold room storage structure.
(ii) To install temperature and relative humidity controller and change some component parts of the cold storage.
(iii) To evaluate its performance on selected fruits and vegetables in terms of cooling rates, physiological weight loss, color changes and firmness
1.4 Justification of the Project
Modification of the existing cold storage structure will bring about the improvement for spacious storing of fruit and vegetables, and proper management of cold room storage with regards to temperature, relative humidity level, air circulation, adequate space between storage bin; prolong the shelf life of all agricultural product and convince the investors on the effective performance of a cold room as a place which can retain and preserve the nutritional quality and value of perishable product over a long period of time.