CHAPTER ONE
1.1 INTRODUCTION
Tomato (Solanum lycopersicum L.) is a berry annual, short–lived herbaceous plant of the solanaceae family. It is a flag-ship species that belongs to the genus of lycopersicon which includes more than 3,000 species with chromosome number of 24; it usually sprawls on the ground, and could reach about 1-5m height (Wogu and Ofuase, 2014). It has a weak woody stem covered with glistering yellow to reddish glandular hairs, rarely vine over other plants.
Tomato plant is cultivated in the savanna agro-ecological zone of Nigeria during cropping season and dry season, under furrow irrigation. The plant usually produces higher yield and better fruit qualities with minimal foliar diseases under irrigation compared to those cultivated during the cropping season. In Nigeria, the major producing areas lie between latitudes 7.50N, 130N and 250C to 340C (Umeh et al., 2002). Global production estimate is put at approximately 130 million metric tons annually on 118.71 million hectares of land (FAO, 2010). In Nigeria it is mostly cultivated in the semi-arid region during the cool dry season using irrigation, high temperature limits the production of tomato to the cooler period of the year.
The fruit is one of the most consumed vegetables in the world, after potatoes and onions, cassava and also the preferred garden crop, ranking 1st in the world for vegetables, with production estimate of approximately 160 million tones, cultivated on 4.8 million hectares in the year 2011 (FAOSTAT 2011, Ogunbawo et al., 2014). Nutritionally, the fruit contains calcium, niacin, flavonoids, lycopene, beta-carotene, derivatives of hydroxycinnamic acid, high amount of water and vitamins, specifically A, C, and E which are very vital in metabolic activities of humans (Greenberg et al., 2015).
The fruit is a versatile health product and due to its equally versatile preparation option, the fruit is consumed as vegetable, dietary supplement, eaten raw as salad and for cooked food or condiment garnishing, contributing to a healthy well-balanced food. Raw, ripened tomato fruit is valuable in food industries and its constitutes of 100g constituents of carbohydrates 4g, energy 75kg (18k) dietary fiber 1g, sugar 2.6g, fat 0.2g, vitamin C (22%, 13 mg), protein 1g, and water 95g (Ijato et al., 2011).
The foods that we take in are rarely if ever stance, they carry microbial associations whose composition depends upon which organisms gain access and how they grow, survive and interact in the food overtime. The microorganisms present will originate from the natural micro-flora of the raw material and those organisms introduced in the harvesting/slaughter, processing, storage and distribution. In most cases, this micro-flora has no discernible effect and the food is consumed without objection and with no adverse consequences. As these micro-organisms manifest their presence in some instances they can cause spoilage, food borne illness and also transform a food’s properties and compositions in a beneficial way food formation.