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The physical, chemical and physicochemical properties of twenty-one Caribbean sweet potato cultivars were investigated. Hunter L a b colour parameters were measured, chroma, colour intensity and hue angle were calculated. Proximate composition, vitamin C, amylose, reducing and non-reducing sugars contents were determined using standard methods. Pasting properties were determined using Rapid Visco Analyser. Tuber size (length, r = 0.72, n = 21, P < 0.0015; width, r = 0.85, n = 21, P < 0.0002) was highly correlated with weight of the tubers. External colours of the tubers (L = 28.7-63.1, a = +5.9 to +18.0, b = +3 to +19.3) were lower than the flesh colours (L = 60.8-84.0, a = )2.4 to +27.8, b = +9.9 to +28.5). Proximate composition is typical of sweet potato cultivars but significant differences exist among cultivars. Total sugar, amylose and amylopectin contents ranged from 1.8 to 4.7%, 15.3-31.2% and 68.8-84.7%, respectively. Cooking profiles of the sweet potato flours showed similar trend. Pasting temperature, peak time, swelling power and solubility ranged from 78.3 to 93.0°C, 3.3-4.8 min, 5.6-23.5 and 11.7-45.7%, respectively.

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Physical, functional and physicochemical properties of flours of five cocoyam (Colocasia spp and Xanthosoma spp) cultivars were evaluated. Colour (L*a*b*) parameters of corms and flours, pasting and functional properties of the flours were determined. Xanthosoma spp showed significantly higher length (95.16-151.46), width (75.29-78.03) and weight (179.20-605.94) than the Colocasia spp., but the parameters did not vary significantly within either Xanthosoma and Colocasia spp. Generally, colour of peeled corms [L* (72.08-78.93 Cocoyam is said to be a giant crop, because its corms, cormels, leaves, stalks and inflorescence are all utilized for human consumption (Chukwu et al. 2008). According to Falade and Okafor (2013), the granule size of cocoyam starch (length =6.47-13.63 μm; width =5.36-8.45 μm) was within the range reported for native cocoyam starch (4-18.7 μm) from Malawian (Mweta 2009). Colocasia spp is reported more suitable for several food products, especially as food for potentially allergic infants, and persons with gastrointestinal disorders (Opara 2002). The cocoyam corms could be processed into many products including poi (fresh or fermented paste, canned, and canned-acidified), flour, cereal base, beverage powders, chips, sun-dried slices, grits, and drum-dried flakes (Owuamanam et al. 2010). However, cocoyam consumption has been affected by the presence of oxalates which imparts acrid taste, and causes sharp irritation and burning sensation in the throat and mouth on ingestion (Akpan and Umoh 2004). This high moisture content (>70 %) associated with high rate of deterioration after harvest, results in its limited availability. Therefore, processing of