Limited or low optimisation of biowaste has pushed modernisation in agriculture that involves food-based plants being grown as a buffer for better profit returns. For cash crop plantation, the plantation area for Sweet potato (Ipomoea Batatas L.) is the second widest after sweet corns in Malaysia (3, 623 hectares). Haulm (unused tops of the plants consisting of stem and leaf) from the sweet potato plant is a potential source for bioactive materials and antioxidants. However, no data is reported on the sweet potato haulm dried juice. Hence, the objectives of this study are: i) to determine the physicochemical properties of unpasteurised and pasteurised sweet potato haulm juice powder, and also ii) to investigate storage stability of unpasteurised and pasteurised sweet potato haulm juice powder (SPHJP) using Ferric Reducing Antioxidant Power (FRAP) assay and Total Phenolic Content (TPC) in 180 days. Results show that pasteurised SPHJP has higher mineral content (13.24 g/100 g dw) and water solubility index (24.30–31.36 g/100 g) than unpasteurised SPHJP. Compared to unpasteurised SPHJP, pasteurised SPHJP also has lower water activity (0.34 aw), carbohydrate content (39.33 g/100 g dw) and phytic acid (0.01 g/100 g dw) (p<0.05). Both SPHJP have produced a minimum protein content of 35.23 g/100g dw. The FRAP activity of unpasteurised and pasteurised SPHJP under light condition followed first-order kinetic degradation with reaction rate of 1.3 x 10-3 and 2.2 x 10-3 day-1, and half-life of 533 days and 315 days, respectively. The half-life of TPC in pasteurised SPHJP under light and dark condition are 100 and 136 days, degraded at 6.9 x 10-3 day-1 and 5.1 x 10-3 day-1, also displayed first-order kinetic model. Meanwhile, the FRAP activity and TPC of pasteurised SPHJP under dark conditions have been stable for 180 days of storage. This study has revealed that the haulm from sweet potato has the potential to be transformed into a sustainable source of antioxidants and an innovative plant-based protein.

Under the cash-crop category, sweet potato (Ipomoea Batatas L.) has the second widest plantation area (3, 623 hectares) in Malaysia, after sweet corn. The sweet potato crop had been grown for its edible tubers, leaving behind the top parts of the plants, which led to abundant agricultural waste, around 10 tonnes per hectare. Early studies showed that haulm (unused tops of the plants consisting of stem, stalk, and leaf) from sweet potato plants are a potential source of nutritional contents,including bioactive materials and antioxidants. Suppose the haulms or other fruit and vegetablewaste (FVW) are utilised as these nutrient sources benefit Malaysia in terms of consumption and economy, promoting agricultural sustainability. In this study, the sweet potato haulm undergoes slow-juicing, heat-treatment, and freeze-drying. This research focused on elucidating the physicochemical and anti-nutrients analysis of pasteurised and unpasteurised sweet potato haulm juice powder (SPHJP) (water activity, colour analysis, water solubility index, oxalic acid, and phytic acid) as a potentially edible product. Results significantly showed that pasteurised SPHJP had lower water activity (0.34 aw), lower anti-nutrients concentration (oxalic acid and phytic acid), and a higher water solubility index than the unpasteurised SPHJP (p<0.05). It is proven that heat treatment is crucial when utilizing green waste material, as it can reduce the availability of anti-nutrients and increase its potential as a replacement for other green vegetables. Further study must be conducted to convert this underutilised agricultural product into biofertilisers, bioplastics, biofuels, or nutraceutical products.