1.1 Introduction
The standard oven has a gas burner or electric elements or both for cooking. As hot air rises, the highest temperature is found towards the top of the oven. This can limit the amount of food which can be cooked at the same at time. It has shelves for different temperature levels. All ovens are available in various sizes, as its important, the oven are used is sufficiently sized to meet its requirement. Gas and electric ovens are available for installations in walls, under benches or as parts of a conventional stove. The type of installation has no effect on energy efficiency or cooking performance.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In the early part of the 19th century, the coal oven was developed. It was cylindrical in shape and made of heavy cast iron. The gas oven saw its first use as early as the beginning of the 19th century as well. Gas stoves became very common household ovens once gas lines were available to most houses and neighborhoods. James Sharp patented one of the first gas stoves in 1826. Other various improvements to the gas stove included the AGA cooker invented in 1922 by Gustaf Dalén. The first electric ovens were invented in the very late 19th century, however, like many electrical inventions destined for commercial use, mass ownership of electrical ovens could not be a reality until better and more efficient use of electricity was available (Takaoğlu, 2012).
An electric baking oven is a heating chamber or an enclosed box-like space which is meant for baking foods. In science and Engineering laboratories, it is in form of a small furnace which is used in the removal of moisture from some Engineering materials in order to improve their physical properties such as ductility and hardness. It can also be used for the purpose of heat treatment of engineering materials such as steel and it's alloy. An Electric baking oven has several advantages over other baking ovens. It is easy to install, moreso relatively damp, portable and has a very easy mode of operation. It is also easy to maintain and has high durability. It is highly preferred to all other types of oven due to the availability of electricity over a wide range of places throughout the countries. Having considered the advantages that can be derived from the use of electric oven, it is relatively cheap when compared with other means of baking.
During the middle Ages, instead of earth and ceramic ovens, Europeans used fireplaces in conjunction with large cauldrons. These were similar to the Dutch oven. Following the Middle- Ages, ovens underwent many changes over time from wood, iron, coal, gas, and even electric. Each design had its own motivation and purpose. The wood-burning stoves saw improvement through the addition of fire chambers that allowed better containment and release of smoke. Another recognizable oven would be the cast-iron stove. These were first used around the early 1700s when they themselves underwent several variations including the Stewart Oberlin iron stove that was smaller and had its own chimney (Bellis, 2018).
More recently, ovens have become slightly more high-tech in terms of cooking strategy. The microwave as a cooking tool was discovered by Percy Spencer in 1946, and with the help from engineers, the microwave oven was patented (Bellis, 2018). The microwave oven uses microwave radiation to excite the water molecules in food causing friction, thus producing heat (Gallawa, 2010).
Electric ovens are the direct fired oven, which effectively distribute heat while being powered by electricity, although this can often result in a higher heating cost for the consumer. Many prefer this type of oven because they tend to use dry heat, which helps prevent the buildup of rust. Electric ovens also feature a thermostat that controls the oven's temperature electronically, and many have top, bottom, or rear grill elements. Electric ovens can take longer to heat, but they are relatively inexpensive in cost compared to other types of ovens.
Wood-fired ovens are indirectly fired ovens that use wood fuel for cooking, while the traditional wood-fired oven is like a masonry oven (mud oven), such ovens can also be built out of cob or iron. Wood-fired ovens are distinct from wood-fired stoves that have a hot cooking surface for pots and pans like electric stove. A wood stove may also have an oven separate from the fire chamber. Regardless of material they all have an oven chamber consisting of a floor (or hearth), a dome and an entry (oven opening).
Gas oven one of the first recorded uses of a gas stove and oven referenced a dinner party in 1802 hosted by Zachaus Winzler, where all the food was prepared either on a gas stove or in its oven compartment. In 1834, British inventor James Sharp began to commercially produce gas ovens after installing one in his own house. In 1851, the Bower's Registered Gas Stove was displayed at the Great Exhibition. This stove would set the standard and basis for the modern gas oven. Notable improvements to the gas stove since include the addition of thermostat which assisted in temperature regulation; also an enamel coating was added to the production of gas stoves and ovens in order to help with easier cleaning. Gas oven is one which works by the liquefied petroleum gas for the baking of the bread, cake and biscuit. The major operational principle of the gas oven is the process of heat transfer. Heat transfer tends to occur whenever there is a temperature difference, and the ways in which heat may be transferred in the gas oven that is convection.
In the oven, the fluid involved is the enclosed air and the burner surface, which provides the solid surface, while the oven walls serve as the solid surfaces. The rate at which heat is transferred across an enclosed oven is calculated from a coefficient based upon the temperature differences of the surfaces. Study of baking oven is important because it could lead to a more efficient process of baking favorable to energy efficiency and better product quality (Fellows, 2000). The baking process usually requires significant energy consumption as relatively high temperature is applied in order to remove moisture in bakery products and create desired texture. Analysis and optimization of baking process and equipment have been conducted for minimizing energy consumption (Therdthai et al., 2003).
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Construction of a Standard Banking Oven (Mini-Oven) with Dual Power Source (Electric / Gas).
1.3 Statement of Problems
Investigation reveals that the wood fired oven has an advantage of the less capital requirement, ease of construction and similarly the wood fired has the disadvantage of longer baking time, the product has not baked uniformly and has the problem of the changing the original flavor of the product.
1.4 Aim and Objectives of Study
The aim of the study is to design and construct a Standard Banking Oven (Mini-Oven) with Dual Power Source (Electric / Gas). In achieving this aim, the following specific objectives were laid out as follows:
- To compare the various ways used in the production of an electric and gas oven.
- To exploit the local facilities available in the construction of the oven as against imported ovens.
- To exhibit the usefulness of a dual-purpose oven in the economy and technology growth of the nation.
- To know the convenience in the use of alternate power source for operation of ovens.
- To discover the basic principle involved in the design and maintenance of a dual purpose oven.
- To disclose the different types of process in the manufacturing of an electric oven and also a gas oven in the past in comparison to the modern days method.
1.5 Significance of Study
The research work is justified for the following reasons:
- It has simple operational method and serves as a medium of exposure to the intricacies of design and fabrication.
- It could be designed and fabricated locally, instead of waiting and longing for it's importation.
This study will be of immense benefit to academic students and other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.6 Scope of Study
The scope of the research is focused on the Construction of a Standard Banking Oven (Mini-Oven) with Dual Power Source (Electric / Gas).
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Establishment Policies: Establishment policies posed a serious limitation as most staffs are not ready to release information needed for this project work. There were lots of information needed from the staffs of this establishment to enhance the study which took them time to release or they did not release at all for security purposes, hence the scope was reduced.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet, questionnaire and interview).
1.8 Definition of Terms
Electric Baking Oven: An electric baking oven is a heating chamber or an enclosed box-like space which is meant for baking foods. In science and Engineering laboratories, it is in form of a small furnace which is used in the removal of moisture from some Engineering materials in order to improve their physical properties such as ductility and hardness.
