PRODUCTION AND PROXIMATE ANALYSIS OF YOGHURT PRODUCED FROM TIGERNUT USING LACTIC ACID BACTERIA (LAB) AS STARTER CULTURE

                                               LIST OF FIGURES

Figures       Title of Figures                                                             Pages

1:         Changes in  pH levels Between the Tigernut Yoghurt Samples

During  Fermentation.                                                      28

2:         Changes In Temperature Between The Tigernut Yoghurt Samples

During Fermentation                                                  29

3:         Changes in Optical Density Between the Tigernut Yoghurt Samples

During Fermentation                                                    30

4:         Changes in Total Titrable Acidity Between the Tigernut Yoghurt

Samples During Fermentation                                        31

CHAPTER ONE

INTRODUCTION

1.1 Introduction

Yoghurt (also spelled “yogurt” or yoghourt”) is considered by most regulating agencies worldwide to be a fermented milk product that provides digested lactose and specifically defined, viable bacterial strains, typically Streptococcus thermophilus and Lactobacillus bulgaricus. It is a source of several essential nutrients, including protein, calcium, potassium, phosphorus and vitamin B₂  and  B₁₂ and it also serves as a vehicle for fortification (Bodot  and Reverend 2013). It is believed that the word “yoghurt’ emanates from the Turkish word “yogurmak” which means to thicken, coagulate or curdle (McGee, 2004). Fermentation of milk sugar (lactose) produces lactic acid which acts on milk protein to give yoghurt it’s texture and it’s characteristics tang (Moore, 2004).

In France, the term “yoghurt” can be used legally only to designate product resulting from milk fermentation brought about exclusively with 2 thermophilic lactic acid bacteria, Streptococcus thermophilus and Lactobacillus bulgaricus which must be found alive in the final product. Traditionally, yoghurt is a fermented whole milk and is believed to posses both nutritional and therapeutic properties beyond those of diary milk which people who are moderately lactose-intolerant can enjoy without ill effects due to the fact that the lactose in the milk precursor is converted  to lactic acid by the bacteria culture (Ghanson, 2008). The reduction of lactose by-passes the affected individual’s need to process the milk sugar themselves.

Yoghurt is known to have medical uses in particular for a variety of gastrointestinal conditions and in preventing antibiotic – associated diarrhea. One study suggests that eating of yoghurt containing  L-acidophitus  helps  prevent  vulvoviginal candidiasis (Ringdahl, 2000). Yoghurt can be presented in large variety. It can be presented as set or stirred (drinking) yoghurt, plain, partly skimmed or skimmed, sweetened or flavoured forms (Imele and Atemmkeng, 2001). The increasing demand from consumers for diary products with functional properties is a key factor driving value sales growth in developed markets. This has led to the promotion of added-value products such as probiotic and other functional yoghurts, reduced – fat and enriched milk products and fermented diary drinks and organic cheese (Rudrello, 2004). Another important global trend is the increasing demand for consumer convenience. Present day consumers prefer foods that promote good health and prevent disease (Khurana and Kanawjia, 2007).  Tiger nuts (Cyperus  esculentus) believed to be a tuber rather than a nut is a minor but important crop in Nigeria, especially the northern region. It is known with many names like zulu nut, yellow nutgrass, ground almonds, chufa, edible rush and rush nut (Eteshola and Oraedu, 2006). In Nigeria, the Hausas call it “Aya”, the Yorubas “Imumu” and the Igbos “Aki hausa” in Southern Nigeria (Omode et al., 2005). Tiger nut tubers are daily ingredient on the diet of many people in North Africa and Spain, the tubers are consumed mainly as a drink called locally “horchata de chufa” (Chufa milk). There are mainly three varieties namely: black, yellow  and  brown and only yellow and brown are readily available in the Nigerian markets. The yellow variety is preferred to all other varieties because of its inherent properties like its bigger size, attractive colour and fleshier body. The yellow variety also yields more milk, contains lower fat and higher phenol (Okafor et al., 2003).

In Northern Nigerian, the nut can be bought in the market all year round and it was also observed that its production is predominantly the work of women farmers as high as 70% and 30% men. The nuts are valued for their highly nutritious starch content, dietary fiber, digestible carbohydrate (Mono, di and Polysaccharides) (Temple et al., 2000). Tiger nuts have been cultivated for both human and livestock consumption. The tubers eaten raw or baked/roasted are about the size of eight peanuts and are abundantly produced in Nigeria. When eaten raw, they make a very acceptance snack and have a flour and texture reminiscent of coconut. They can be rehydrated by soaking before consumption and even softened further by boiling. Tiger nuts are rich in oil which can be extracted for culinary and industrial use (Mason, 2008).

According to Mason, (2008), tiger-nuts has long been recognized for it’s health benefits as they are high in fibre, protein and natural sugars. They have a high content of soluble glucose and oleic acid, along with energy content (starch, fats, sugars and proteins), they are rich in minerals such as phosphorus and potassium and  in vitamin E and C. Tiger nuts are believed to help prevent heart attacks, thrombosis and  cancer especially  of the colon. They are thought to be beneficial to diabetics and those seeking to reduce cholesterol or lose weight. The very high fibre content combined with its delicious taste makes tiger nuts ideal for healthy eating (Beniwal, 2004). These numerous advantages and health benefits associated with tiger-nuts makes it more attractive as an alternative source of milk in yoghurt production (Martinez, 2003).

Therefore, tiger-nut, with its inherent nutritional and therapeutic advantage could serve as a good  alternative  to cow  milk in the production  of  yoghurt.  In addition, the inclusion of tiger-nut milk in the production of yoghurt could reduce the price of yoghurt and make it more affordable to many Nigerians.

 This research work is limited to use of  laboratory isolated and commercially processed lactic acid bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) for the production of yoghurt using tiger nut milk and proximate analysis of the sample.

Animal milk (cow, goats, camels, ewes, sheeps) is commonly available worldwide and as such is the milk most commonly used to produce yoghurt. Diary product (milk) are been consumed in substantial amount despite scientific evidence that questions their health benefits and indicates their potential health risks. Consumption of diary products has also been linked to higher risk for various cancers, especially cancer of the reproductive systems. Most significantly, diary product consumption has been linked to increased risk for prostrate and breast cancers. Lactose intolerance is common among many populations. The systems includes gastrointestinal distress, diarrhea, and flatulence (Bodot and Reverend, 2013).

Diary products all contributes significantly to the amount of cholesterol and saturated fat which can increase the risk of heart disease and can cause other serious health problems. Diary products may also contain contaminants such as pesticides, polychlorinated biphenyls (PCBs), and dioxins which do not readily leave the body and can eventually build to harmful levels that may affect the immune reproductive and the central nervous systems(Warensjo et al., 2004).

 The study of this research topic will provide more constructive frame work to formations of creating a ways of eradicating the health challenges and risk factors associated with diary milk in yoghurt production. The tiger nut apart from minimizing the risk factors associated with diary milk, is necessary fir bones, tissue repairs,  muscles, growth and development of the body and rich in vitamins E  and C. It is also recommended for those who suffer digestive enzymes like catalase, lipase and amylase. The high content of oleic acids on cholesterol thereby preventing heart attack, thrombosis and activates blood content of soluble glucose. The plant milk also supplies the body with enough quantity of vitamin E essential for fertility in both men and women. The milk has a relatively high antioxidant capacity which is capable of protecting the body against malnourishment.

1.2       Aims and Objectives

1.     To isolate, characterize and inoculate lactic acid bacteria in milk sample, isolated from procured fermented milk product.

2.     To produce yoghurt from tiger nut using laboratory isolated lactic acid bacteria.

3.     To evaluate the proximate attributes of  yoghurt produced from tiger nut using  laboratory isolated and commercially purchased lactic acid bacteria.

Buyers has the right to create dispute within seven (7) days of purchase for 100% refund request when you experience issue with the file received. 

Dispute can only be created when you receive a corrupt file, a wrong file or irregularities in the table of contents and content of the file you received. 

ProjectShelve.com shall either provide the appropriate file within 48hrs or send refund excluding your bank transaction charges. Term and Conditions are applied.

Buyers are expected to confirm that the material you are paying for is available on our website ProjectShelve.com and you have selected the right material, you have also gone through the preliminary pages and it interests you before payment. DO NOT MAKE BANK PAYMENT IF YOUR TOPIC IS NOT ON THE WEBSITE.

In case of payment for a material not available on ProjectShelve.com, the management of ProjectShelve.com has the right to keep your money until you send a topic that is available on our website within 48 hours.

You cannot change topic after receiving material of the topic you ordered and paid for.