1.1 Introduction
The word “Yeast” comes to us from the old English gist, gyst and from the indo-European root yes-meaning boil, from or bubble. Yeast microbes are probably one of the earliest domesticated organizing. People have used yeast for fermentation and baking throughout history. Archaeologists digging in Egyptian ruins found early grinding stones and baking chambers for yeasted bread, as well as drawings of 4,000. years- old bakeries and breweries. (Phillips 2012) in 1680, the Dutch naturalist Anton van leeuwenhock first microscopically observed yeast but at the time he did not consider them to be living organisms but rather globular structures (Huxley, 1871) in 1857 French microbiologist louis Pastear. Proved in the paper “memire sur la fermentation alcoolique” that alcoholic fermentation was conducted by living yeasts and not by a chemical catalyst. (Barntt 2003). Pasteur showed that by bubbling oxygen into the yeast broth, cell growth could be increased but fermentation was inherited as an observation cater called the “Pasteur effect”
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 Statement of Problems
Investigation reveals that temperature can affect the sensitivity of yeasts to alcohol concentration, growth rate, rate of fermentation, viability, length of lag phase, enzyme and membrane function, etc. Because yeast strains differ in response to temperature, the optimum temperature for vinification can vary widely (Jackson, 2000). Several factors affect yeast growth during alcoholic fermentation, including clarification of grape juice, addition of sulphur dioxide, temperature of fermentation, composition of grape juice, inoculation with selected yeasts, and interactions with other organisms.
1.3 Aim and Objectives of Study
The aim of the study investigates the Effect of Temperature on the Growth of Yeast. In achieving this aim, the following specific objectives were laid out as follows:
- To examine the Yeast growth effect of temperature
- To determine the Species and Fermentation in Yeast
- To examine the Effect of Temperature on Kinetic and Yield Parameters
1.4 Significance of Study
Yeast can significantly reduce the production costs of biomass conversion to ethanol. However, little information is available about the underlying genetic changes and physiological functions required for yeast thermotolerance. We recently revealed the genetic changes of thermotolerance in thermotolerant yeast strains (TTSs) generated through adaptive laboratory evolution. Here, we examined these TTSs’ physiology and computed their proteome stability over the entire thermal niche, as well as their pre-adaptation to other stresses. Using this approach, we showed that TTSs exhibited evolutionary trade-offs in the ancestral thermal niche, as well as reduced numbers of growth functions and pre-adaptation to other stresses found in ethanol production processes. This information will be useful for rational engineering of yeast thermotolerance for the production of bio-fuels and chemicals.
This study will be of immense benefit to 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.
1.5 Scope of Study
The study focuses on the Effect of Temperature on the Growth of Yeast.
1.6 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.
- 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).
1.7 Definition of Terms
Yeast: It comes to us from the old English gist, gyst and from the indo-European root yes-meaning boil, from or bubble
Effect: a change which is a result or consequence of an action or other cause.
E.coli: Is an acronym for Escherichia coli which is a bacterium commonly found in the intestines of humans and other animals, some strains of which can cause severe food poisoning.
Staphylococcal: Staphylococcus (staph) is a group of bacteria. There are more than 30 types. A type called Staphylococcus aureus causes most infections. Staph bacteria can cause many different types of infections, including; skin infections which are the most common types of staph infections.
Isolates: isolate simply means cause (a person or place) to be or remain alone or apart from others.
Phytochemical: This is a substance produced mainly by plants, and these substances have biological activity.
Component: it simply means one part of a whole thing.
Antibacterial: Anything that destroys bacteria or suppresses their growth or their ability to reproduce. Heat, chemicals such as chlorine, and antibiotic drugs all have antibacterial properties.
