ABSTRACT
Vegetables are plants cultivated for food. Generally, they are less sweet than fruits and often require processing to increase their edibility (Little et al., 1973). Fermentation, as described in previous chapters, is a “slow decomposition process of organic substances induced
7.1 Introduction 199 7.2 Fermented Vegetables around the World 200
7.2.1 Introduction 200 7.2.2 Sauerkraut 201 7.2.3 Pickles 202 7.2.4 Kimchi 202 7.2.5 Lafun 203
7.3 Production Methods 203 7.4 Fermentation Engineering 204
7.4.1 Bioreactions in Vegetable Fermentation 205 7.4.2 Bacterial Community in Fermented Vegetables 205 7.4.3 Control of Fermentation 207
7.4.3.1 Low Concentration of Oxygen 207 7.4.3.2 Temperature 208 7.4.3.3 pH 208 7.4.3.4 Inhibitors 208
7.4.4 Metabolism 208 7.5 Function of Fermented Vegetables 211 7.6 Safety Issues of Fermented Vegetables 211 7.7 Perspective 212 References 212
by micro organ isms, or by complex enzymes of plant or animal origin” (Walker, 1988). is technology is one of the oldest biotechnologies used in food processing. e exact origins of preservation of vegetables by fermentation are unknown, whereas the birth of fermented vegetables is thought to be in China, where a fermented mixture of vegetables was given to laborers during the construction of the Great Wall around 300 (Pederson, 1979). Fresh vegetables are easy to contaminate due to the high water activity (aw) and nutrient content. Vegetable fermentation initially comes from food preservation, which results in products with a longer shelf life than fresh vegetables. Hence, fermented vegetables guarantee longer quality maintenance and availability of vegetables during the off-season. Although a number of other vegetable preservation methods are available today, fermentation is still taken as a highly appropriate technology in developing countries and remote areas because of the high efficiency and low energy costs for food manufacture. Besides being preserved, fermented vegetables are known to have remained palatable and have no or less antinutrients (Muchoki et al., 2010). is is another reason why it remains an important process in both developed and developing countries. Apart from the improvement of food security and nutrition, vegetable fermentation is culturally and economically important, which benefits people through the following aspects: (1) increasing income and employment, (2) improving cultural and social well being, and (3) health benefits (Battcock and Azam-Ali, 1998).
