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7. Good Manufacturing Practices for Processing of Tropical Roots and Tubers
Anakalo A. Shitandi 1 and Marion G. Kihumbu-Anakalo 2
1 Kisii University, Kisii, KENYA
2 Department of Food Science, Egerton University, Egerton, Kenya
7.1 Introduction
Root and tuber crops are regularly grouped together because they are bulky, perishable and vegetatively propagated (Scott et al., 2000). These crops can be grown and produced under a broad variety of climatic and diverse ecological conditions, so the biological and chemical hazards may also vary. The preservation of roots and tubers is accomplished by retarding processes of putrefaction caused by inherent microorganisms and enzymes. Processing consequently improves safety, keeping quality and digestibility, promotes palatability, and inactivates enzyme inhibitors and other anti-nutritional factors (Boeke et al., 2010).
The roots and tubers contain high dry matter in the form of starch, thereby offering a wide scope for value addition into foods, food additives, beverages, and animal and poultry feeds (Ray and Sivakumar, 2009). Processors seek to transform the roots and tubers into alternate foods that are desirable and add variety to the diet. Fermentation is frequently employed in several instances to convert tropical roots and tubers into valued-added produce. The major part of cassava in Africa and Latin America is processed into fermented foods and food additives such as organic (acetic, citric and lactic) acids, mono-sodium glutamate, etc. (Ray and Sivakumar, 2009). Sweet potatoes can be fermented into products such as lacto-pickles, sochu, soy sauce, vinegar, lacto-juices, etc. (Oloo et al., 2014; Ray and Sivakumar, 2009). Likewise, other tropical roots and tubers can also be converted into different fermented products.
Biological, chemical and physical hazards exist during processing and this may vary extensively from one type of production to another, making it essential to consider manufacturing practices that promote the production of safe root and tuber produce.
With globalization and a greater movement of food across borders, quality and safety have become issues of concern (Hammoudi et al., 2009; Sylvaine, 2013). Regional authorities are taking measures to improve the quality of roots and tubers and there are efforts to assure that consumers’ health is protected resulting in increased governmental and regulatory approach towards food safety. It is then critical that safety be embodied in root and tuber products from raw materials to consumption.
7.2 Good Manufacturing Practices (GMP)
Good manufacturing practices are implemented to prevent hazards or contamination from entering into foods. The products can be contaminated by number of reasons, like the actions of people, other food materials such as undeclared allergens, packaging materials, cleaning and sanitizing agents, pesticides, chemicals, lubricants, etc., along with a host of other things. These are prerequisite programmes, which may provide the basic environmental and operating conditions that are necessary for the production of safe and wholesome food. Good manufacturing practices (GMPs) describe the conditions and practices that are necessary for the processing, packaging or storage of food to ensure its safety and wholesomeness (www.foodsafetymagazine.com). GMPs are also explained as the combination of manufacturing and quality control procedures that ensure consistent quality products meeting desired specifications. GMPs are preventive controls, which assist to control microbial, chemical and physical hazards linked to different stages of production ranging from primary production to packaging (Codex Alimentarius Commission, 2014; Dunkelberger, 1995). They are the basis of preparation of safe food and are the minimum requirements in processed foods.