Avocado is a fruit from a tree that has a variable growth and development, reaching a height of 10 to 12 m in its natural habitat.  Mature trees over 8 years old produce fruit all year round.  Avocado is cultivatedthroughout tropical and subtropical regions of the world, with Mexico the largest producer. The fruit has an exquisite taste and aroma, a high nutritional value and various medicinal benefits. Post-harvest handling is critical to fruit quality; mechanical damage, over chilling and fungal contamination are the most common causes of loss. There is a large world-wide market for predominantly fresh fruit but also for processed foods and cosmetic products.

Barley grain ranks fourth in cereal production, with a world output of 136 million tonnes in 2007 (FAOSTAT). The crop requires a temperate climate; the principal growing areas are Europe and the Russian Federation but it is also a valuable and resilient crop in arid and semi-arid areas of Asia, the Middle East and North Africa. It is predominantly used as flour for human consumption, in animal feed and as malt in alcoholic beverages.

Cacoa (Theobroma cacao) is a small (4–8 m tall) evergreen tree in the family Malvaceae, native to the deep tropical regions of Central and South America. Its seeds, cocoa beans, are used to make cocoa mass, cocoa powder, and chocolate. Cacao production has increased from 1.5 million tons in 1983-1984 to 3.5 million tons in 2003-2004, almost entirely due to the expansion of the production area rather than to yield increases. Cacao is grown both by large agroindustrial plantations and small producers, the bulk of production coming from millions of farmers who have a few trees each. A tree begins to bear when it is four or five years old. A mature tree may have 6,000 flowers in a year, yet only about 20 pods. About 1,200 seeds (40 pods) are required to produce 1 kg (2.2 lb) of cocoa paste.

Cassava is an edible root that provides an important source of carbohydrates for an estimated 500 million people in Africa, Asia and the Americas. World production was 230 million tonnes in 2008, with Nigeria as the largest producer followed by Brazil, Thailand and Indonesia (FAOSTAT). Key post-harvest considerations include the rapid deterioration of roots two to three days after harvesting and the presence of cyanides, which need to be detoxified during processing to make the root safe for consumption.

Coconut, the fruit from the coconut palm tree is widely grown throughout the tropics. The palm trees grow to 30 m and require a continuous frost-free warm climate, plenty of rain and sunlight. India, Indonesia and the Philippines are the largest producers. An adult palm tree will produce coconut fruits every month throughout the year. Young immature coconuts are harvested for coconut water, a nutritious drink, and mature fruits for the white ‘meat’ and oil. A wide range of coconut products are internationally traded .In addition to their high nutritional value, coconut products also have various medicinal properties.

Cowpea is a legume that is extensively grown, particularly throughout sub-Saharan Africa. It is a subsistence crop, often intercropped with sorghum, maize and pearl millet. The peas provide valuable protein, the leaves are used as a nutritious vegetable and the rest of the plant serves for animal feed. The plants are drought tolerant and grow well on relatively poor soils. The peas can be consumed fresh or removed from the pods and dried.

Edible aroids are root crops grown widely in tropical and sub-tropical countries. Taro also known as cocoyam and tannia are the more common species. World taro production in 2008 was over 11 million tonnes principally in Cameroon, China, Ghana and Nigeria, with smaller production in other areas of Africa, Asia and South Pacific (FAOSTAT). The corms provide a useful carbohydrate source but must be cooked prior to consumption to detoxify the calcium oxalate crystals present. The growing season ranges from 6 to 12 months depending on the species. The short storage life of aroids at ambient temperatures of only 2 to 6 weeks is a limiting factor in their use.