1.1 Introduction
Moulds are a type of fungi that can proliferate in various food products, including baked items such as bread and cake, which are staple foods in many diets (Pitt & Hocking, 2009). These fungi not only affect the aesthetic quality and shelf life of baked goods but also pose potential health risks to consumers (Samson et al., 2010). Fungi that grow in the form of multicellular filaments known as hyphae. Moulds are a common cause of food spoilage and can produce mycotoxins that are harmful to human health (Pitt & Hocking, 2009). Mould contamination in baked foods is a common issue, driven by factors such as improper storage conditions and high moisture content (Klich, 2002). The presence of moulds in bread and cake can lead to mycotoxin production, which is harmful when ingested. Mycotoxins, such as aflatoxins and ochratoxins, are toxic compounds produced by certain mould species that can have severe health implications, including carcinogenic effects (Cary et al., 2007).
This chapter will address the background information that motivated this study, the challenges that prompted it, its aim, and its objectives as a preface to subsequent sections of the study. Additional factors include the study's significance, scope, limitations, research questions and hypotheses, and the definition of technical terms.
1.2 Background of Study
In the mid-20th century, researchers began focusing more specifically on mould contamination in food products. Studies such as those by Pitt and Hocking (2009) provided comprehensive insights into the types of moulds commonly found in food, including baked goods. These studies used selective media to isolate mould species from various food products, including bread and cake, and identified the conditions that favor mould growth (Pitt and Hocking, 2009). The 1970s and 1980s saw significant advancements in the identification and classification of moulds. The development of techniques such as fungal taxonomy and molecular methods allowed for more precise identification of mould species. Research during this period highlighted the impact of mould contamination on food safety, emphasizing the importance of detecting and managing moulds to prevent mycotoxin production (Klich, 2002).
The current state of research incorporates advanced microbiological and molecular techniques to isolate and identify moulds in baked foods more accurately. Modern studies continue to build on previous findings, aiming to improve food safety and quality control measures in the baking industry (Samson et al., 2010). In recent decades, the focus has expanded to include the health risks associated with mycotoxins produced by moulds in food. Studies by Cary et al. (2007) explored the various mycotoxins and their effects on human health, underscoring the need for rigorous monitoring of mould contamination in food products, including baked goods.
Baked goods, particularly bread and cake, provide an ideal environment for mould proliferation due to their high moisture content and nutrient-rich composition. The presence of moulds can lead to spoilage, resulting in undesirable changes in texture, flavor, and appearance, which compromises the quality of the food products (Samson et al., 2010). Beyond these quality issues, moulds can produce mycotoxins—harmful secondary metabolites that pose serious health risks when ingested. Mycotoxins, such as aflatoxins and ochratoxins, have been linked to various health problems, including immunosuppression and carcinogenicity (Cary et al., 2007).
Bread may be served in different forms at any meal of the day, eaten as a snack and is even used as an ingredient in other culinary preparations. As a basic food worldwide, bread has become significant in religious rituals, secular cultural life and languages. Bread is prone to spoilage problems. These include physical, chemical and microbial spoilage. Mould growth is the major economic importance of bread and is a serious and costly problem for bakeries and consumers. The moulds involved in the spoilage of bread include Rhizopussp, Penicilliumsp, Eurotiumsp, Aspergillus sp and Moniliasitophila. One of the most common is Rhizopusstolonifer, often referred to as the bread mould.
Economic losses of bread due to mould spoilage are between 1% and 5% depending on the type of product, season and the method of processing. In addition to the economic losses associated with bread, another concern is the possibility of mycotoxins production by some moulds. The concentration of nutrients also determines the rate of mould growth in bread. The growth of mould in bread is a substrate-saprophyte relationship with the bread providing nourishment and the mould surviving on it as long as favourable environmental conditions prevail.
Mould growth in bread is also favoured by their ability to synthesize proteolytic and amylolytic enzymes. Furthermore, moisture condensation on a bread surface due to packaging while the product is not completely cool, may be conducive to mould growth. Therefore, in Nigeria where the research was carried out, the activities that was conducted is to isolate, characterize and identify the filamentous fungi associated with the spoilage of commercial bread in Enugu, Nigeria so as to educate the consuming public on the danger inherent in the consumption of such spoilt bakery product.
1.3 Statement of Problems
Investigation revealed that the major cause of growth of mould in baked food is long storage. Baked product being food consumed entails large purchase from bakery, and at times the sellers do not finish the sale within a week. These long storage causes growth of mould, resulting to food poisoning as a result of the toxins produce by these mould infected bread. The problem of mould contamination in baked foods such as bread and cake poses significant challenges in terms of food safety and quality control. Moulds can adversely affect the shelf life and safety of these products, leading to economic losses and potential health risks for consumers (Pitt & Hocking, 2009).
Another critical problem is the production of mycotoxins by certain mould species, which can occur in contaminated baked foods. Mycotoxins, such as aflatoxins and ochratoxins, are toxic compounds that pose serious health risks, including carcinogenicity and immunosuppression, when ingested (Cary et al., 2007). The identification of mould species responsible for mycotoxin production is essential for assessing the risk and implementing appropriate safety measures.
Furthermore, existing methods for detecting and identifying moulds in food often face limitations in accuracy and sensitivity. Traditional microbiological techniques may not always provide precise identification of mould species, leading to potential underestimation of contamination levels (Samson et al., 2010). The development and application of advanced techniques are necessary to improve detection and ensure comprehensive monitoring. Hence, it is against this backdrop that this study aims to identify the moulds on baked food.
1.4 Aim and Objectives of Study
The aim of the study is to isolate and identify the moulds on baked food (bread and cake). In achieving this aim, the following specific objectives were laid out as follows:
- To isolate moulds from bread and cake samples obtained from various sources, using selective media and microbiological techniques;
- To identify the isolated mould species using morphological, microscopic, and molecular methods, such as PCR and sequencing;
- To evaluate the conditions under which specific mould species grow and proliferate in baked foods;
- To assess the prevalence and distribution of different mould species in the bread and cake samples; and
- To provide recommendations for improving food safety and quality control measures in the baking industry based on the study findings.
1.5 Research Hypothesis
In order to pursue the objective of this study, the following generalized statements have been designed to guide and aids in obtaining the result for the experiment to be conducted. For this work, the null hypothesis will be represented with H0 while the alternative hypothesis will be represented with hypothesis H1.
- H01: Filamentous fungi and yeast has no effect on bread.
- H02: Filamentous fungi and yeast are responsible for spoilage of bread when infested.
1.6 Significance of Study
The findings from the study on "Isolation and Identification of Moulds on Baked Food (Bread and Cake)" will have significant implications for various stakeholders.
- For food manufacturers, the study will provide valuable insights into the types and prevalence of moulds that commonly contaminate baked goods, which will inform better quality control practices and help in developing effective strategies to prevent mould contamination.
- Consumers will benefit from the study as it will enhance food safety by identifying potential health risks associated with mould contamination and mycotoxin production, leading to improved safety standards for baked products they consume.
- Regulatory agencies will gain a clearer understanding of mould contamination issues in baked foods through this research, which will aid in updating and enforcing food safety regulations and standards to ensure higher levels of consumer protection.
- Researchers and academics will find the study valuable for its contribution to the existing body of knowledge on moulds in food, providing a basis for further research and advancements in microbiological techniques for detecting and identifying foodborne contaminants.
- The baking industry as a whole will benefit from the study's recommendations for better storage and handling practices, which will help reduce economic losses due to spoilage and improve the overall quality and shelf life of baked products.
Furthermore, the isolation and identification of mould in baked product would provide a knowledge of the effect of mould on the baked product, these would thereby improve the needs to preserve baked foods (Bread and cake), and reduce the rate of food poisoning from consumers of the product.
1.7 Scope of Study
The scope of the research is focused on the Isolation and Identification of Moulds on Baked Food (Bread and Cake).
1.8 Limitations of the Study
During the course of this study, there were some problems encountered which stood as limitations to the research work. Some of the limitations include:
- Delays in receiving responses from respondents, which impacted the timely collection and analysis of samples. These delays hindered the overall progress of the study and affected the schedule for data analysis and reporting.
- Financial constraints also posed a challenge. The cost associated with purchasing specialized media, laboratory equipment, and conducting molecular analyses was substantial. This financial limitation restricted the scope of the study and the ability to conduct more extensive or repeated tests, potentially affecting the comprehensiveness of the findings.
- Time constraints were another significant limitation. Balancing the research with other academic responsibilities and commitments was challenging. This constraint limited the amount of time available for conducting thorough investigations and extended the duration needed to complete the study.
1.9 Definition of Terms
In the course of this research study, several key terms are defined to clarify the scope and methodology of the research:
Moulds: Fungi that grow in the form of multicellular filaments known as hyphae. Moulds are a common cause of food spoilage and can produce mycotoxins that are harmful to human health (Pitt & Hocking, 2009).
Isolation: The process of separating a specific microorganism from a mixed sample to study its characteristics. in the context of this study, isolation involves separating moulds from bread and cake samples using selective media to facilitate their identification (Samson et al., 2010).
Identification: The process of determining the species or type of microorganism isolated from a sample. This typically involves morphological examination, microscopy, and molecular techniques such as polymerase chain reaction (PCR) and sequencing to accurately classify mould species (Klich, 2002).
