Rootcrops are generally rich in complex carbohydrates and dietary fiber. Starchy roots and tubers are mainly used as human food, animal feed or manufactured to produce starch and alcohol.
According to the Food and Agriculture Organization (FAO) of the United Nations (UN), root and tuber crops are a staple food and main source of calories for an estimated 700 million poor people in Africa, Asia, and Latin America.
The National Nutrition Survey (NNS) conducted by the Food and Nutrition Research Institute of the Department of Science and Technology (FNRI-DOST) in 2008 revealed that starchy roots and tubers are consumed at 17 grams daily or about two percent of the total food intake of Filipino households.
The NNS found that there is a decreasing trend in consumption of starchy roots and tubers among Filipino households from 1978 to 2008. Sweet potato is one of the commonly consumed starchy roots and tubers in the Philippines, along with potato, taro or gabi, and cassava.
Around four percent of Filipino households eat sweet potatoes regularly. Sweet potatoes or locally known as kamote, a seasonal root crop grown in tropical and subtropical regions like the Philippines, is rich in beta-carotene, vitamin B6, manganese, and potassium.
In impoverished families in the provinces and in some parts in the metro, sweet potatoes are an important food crop for they are much easier to cultivate and more affordable than rice, hence an excellent source of energy and nutrients for the entire family.
Sweet potatoes, though often eaten as is after boiling or baking, are common ingredients in some Filipino delicacies such as sinigang or sour soup, ginataan or sweetened coconut milk dish with various root crops, jackfruit, and glutinous rice balls, and kamote-cue or sugarcoated sweet potato slices fried and skewered on thin bamboo sticks.
Seeing the potential goodness of sweet potatoes, the FNRI-DOST developed frozen, ready to-fry sweet potato fries using food extrusion technology. Food extrusion is a very important food processing operation.
Extrusion is a process in which the food ingredient is pushed through an orifice or a die of a given shape. It mixes and shapes foods such as biscuit dough and pasta without cooking them, using cold extrusion, while producing a wide range of products such as crisp snack foods and sugar confectionery using hot extrusion.
After a series of sensory evaluation from panelists, the ready-to-cook sweet potato fries were found acceptable and safe.
It contains 505 calories of energy, 1.8 grams of protein, 4.7 grams of dietary fiber, and 854 micrograms (µg) of beta-carotene per 100 grams, thus a good source of vitamin A.
With appropriate packaging strategies and shelf-life studies, the ready-to-cook sweet potato fries extrusion technology can be transferred to interested small and medium businesses or local government units for their livelihood or social projects.