ABSTRACT
While the human population in the world is increasing, there is a corresponding reduction in the agricultural land for farming. Additionally, global warming is having a deleterious impact on agricultural productivity with dire consequences on the food supply for both developed and developing countries (Rosenzweig and Parry 1994). Luckily for Africa, it is particularly rich in traditional fermented foods, particularly plantbased fermented foods, which are produced using minimal technology and inputs (Odunfa 1985). However, sub-Saharan Africa has the highest percentage of chronically malnourished people in the world (OECD-FAO 2011). The reasons for this are mainly agronomic constraints and lack of appropriate local processing techniques. Accordingly, a huge proportion of ca. 30 to 50 per cent of harvest is lost at the postharvest stage (Shiundu and Oniang’o 2007). The main causes for this are inadequate production conditions (Abukutsa-Onyango 2007, Diwani and Janssens 2001) as well as rapid product decay during transport, storage and marketing (Muchoki et al. 2007). Future issues surrounding global food supply and security are posing a challenge if adequate attention is not placed on traditional food production, sustainable preservation and reduction of food waste in different continents. The endeavor to provide sufficient food on a worldwide scale will require a proper understanding of the lesser known crops, low-cost preservation techniques and new methodologies of production and processing that can guarantee adequate food availability (Huang et al. 2002). For example, Africa’s large quantities of different agricultural
harvests can meet the increasing needs of other parts of the world. Many African produce are drought-resistant and these tropical crops are grown in abundance. Therefore, effective post-harvest strategies based on sound scientific principles need to be developed for efficient crop utilization. The strategies must be applicable and adaptable to different situations in African countries where there are varying levels of infrastructure and technology. Africa also is a region where a very high variety of diverse food crops is grown. Vegetables and fruits are produced throughout the continent, but due to limited industrial-scale processing of agricultural products, large economic losses of up to 40 per cent are experienced, and as a consequent, poverty and hunger (Gustavsson et al. 2011). Traditional methods of processing and value addition to vegetables and fruits have a long history throughout Africa (Steinkraus 1985). Odunfa (1985) identified food processing that involved fermentation as an important method to facilitate the availability of food and support food security throughout the continent. Available information shows that archeological and anthropological records, as well as the available documented history of African foods and diets show that food fermentation originated by trial and error, before it became an art. Subsequently techniques were transferred from one generation to the other (Odunfa 1985, Stanton 1985, Battcock and Azam-Ali 1998, Deshpande et al. 2000). Climatic conditions characterized by high humidity and temperatures contribute to the diversity and quantities of agricultural produce in Africa. The need to adopt preservation and optimize traditional techniques for this has been emphasized to greatly influence the type of food that can be fermented, as well as the scale at which it should be done (Sanni 1993). Cereals and tubers, as well as legumes, fruits and vegetables are produced in large quantities in many parts of Africa and because of their perishable nature, they are subject to post-harvest processing. Postharvest processing based on fermentation is used to produce and increase the shelf-life of a variety of foods at either household or small-scale, cottage-type businesses in Africa since decades (Odunfa 1985, Steinkraus 1995). The many advantages of fermenting agricultural produce have been recognized throughout the continent as an important strategy for improving palatability, detoxification, mineralization, as well as increasing shelf-life and digestibility. The significance of food fermentation as a sustainable post-harvest technology, especially in developing countries, has become well-recognized by FAO published global perspectives (Battcock and Azam-Ali 1998, Haard et al. 1999, Deshpande et al. 2000). Apart from contributing to the dietary intake of the people, it improves safety, quality, availability of foods and generates income for the food processors. The aim of this chapter is to describe different lactic acid fruit and vegetable fermentation processes that are currently in use in Africa. In addition, the involvement of different lactic acid bacteria (LAB) populations
associated with fermentation, and possibly other microorganisms associated with such fermentations will be discussed. The beneficial roles, which traditional fermented foods play in the diet and health of the consumer will also be addressed, and so will be the development of concepts that could facilitate process optimization, safety and quality, which may potentially lead to the development of functional foods. Fruits and vegetables produced in different regions of Africa are classified as fruits, starchy vegetables, protein-oil seeds and leafy vegetables. Very high percentages of fruits and vegetables are consumed after harvest in Africa. In many countries, traditional processing of fruits and vegetables play an important role in the food supply, especially during off-seasons and harvest.
