Investigation on Sustainable Source of Nutrients from Fresh and Pasteurised Sweet Potato Haulm Juice Powder

The push for modernisation in agriculture involves food-based plants as a buffer
for more profitable returns. In Malaysia, the second widest cash-crop plantation is for sweet
potato (Ipomoea batatas L.), occupying 3, 623 hectares of agricultural land. Furthermore,
its haulms are discarded as waste. There are limited studies on the macronutrients of sweet
potato stalk, stem and leaves, collectively known as the haulm. This study investigates
the proximate nutritional composition of fresh and pasteurised sweet potato haulm juice
powders (SPHJPs). The pasteurisation process has significantly reduced carbohydrate
content (39.33 g/100g dry weight (dw)) and increased mineral content (13.24 g/100g dw)
compared with fresh SPHJP (p<0.05). The fresh and pasteurised SPHJP had a minimum
percentage of protein (35.23 g/100g dw), fibre (7.72 g/100g dw) and fat (2.42 g/100g
dw), revealing that the haulm from sweet potato has the potential to be transformed into
a sustainable source of nutrients and as an innovative plant-based protein. The current
information is crucial in imparting dietary recommendations on utilising sweet potato
haulm as part of human or animal diet. Future studies that emphasise on the micronutrient
and antinutrient contents of the haulm are recommended