Recommended planting and cooking methods for Orange fleshed sweet potatoes

What is it about?

Findings from the investigations on the effects of different soil nutrient managements and cooking methods on nutrient and phytochemical composition of orange-fleshed sweet potato (Umudike Sweet Potato Variety 3) (UMUSPO 3 Ipomea batatas) are reported in this article. UMUSPO 3 potato vines (main plot) were planted on eight sub- plots treated with different soil nutrients (Poultry manure, agrolyser and NPK) combinations (VB1 – VB8) and a control (VB9) at the National Root Crops Research Institute experimental farm, Umudike, Abia State, Nigeria. Potato tubers were harvested after 4 months of planting and both cooked and raw samples were subjected to chemical and sensory analysis. Carbohydrate and dry matter contents were highest and respectively 16.4% and 29.79% in potatoes harvested from the control soil (VB9). Both control and treated soils yielded potatoes that were high in calcium (86.94 – 96.47 mg/100g), magnesium (73.62 - 86.87 mg/100g), phosphorus (151.26 - 195.97 mg/100g), potassium (790.30 – 901.54 mg/100g) and sodium (74.50 – 81.84 mg/100g). Only soil treatments with NPK 15:15:15 at 400 kg/ha (VB5) improved protein contents of raw potatoes from 5.26% to 6.13% while other soil treatments decreased the protein content. Potato harvested from the control and various soil treatments (VB1 –VB8) were rich in vitamin C (53.34 – 95.37 mg/100 g) and carotene (28.52 – 29.73 mg/100 g) but relatively low in the B vitamins. Soil treatments VB1 to VB8 did not improve vitamin contents of potatoes beyond that of the control for vitamin B1. Cooking methods and cooking time affected carotenoid retention in UMUSPO 3 potato. Carotenoid retention was higher in oven-dried samples than in roasted and boiled samples. Oven-drying for 24h decreased total carotenoid retention to 76.4%, and for 48h to 36.3%. Boiling for 10 min decreased carotenoid content to 56.4%, and for 30 min to 17.1%. Roasting for 10 min reduced it to 50.6%, and for 30 min to 30.9%.

Featured Image

Photo by Louis Hansel on Unsplash

Photo by Louis Hansel on Unsplash

Why is it important?

Oven-drying improves nutrient retention in orange fleshed sweet potatoes

Perspectives