Chemical and Sensory Characteristics of a Hydroponic Sweetpotato During Storage

Sweetpotato (Ipomoea batatas) is an economic root crop that has been selected as a candidate crop to be grown on space missions by the U.S. National Aeronautics and Space Mission. This study determined the chemical and sensory behavior of hydroponically grown sweet potato (TU-82-155) during storage. Cured hydroponically grown sweet potatoes (HSP) were stored in palletized crates at 13°C and 80% RH for 42 days. Samples were randomly withdrawn at 0, 7, 14, 28, 35 and 42 days of storage for chemical, instrumental, and sensory analyses. Judges utilized a “just-about-right” attribute scale with five categories to assess the intensity of five sensory attributes. The HSP had a high moisture throughout storage, reflecting an overall mean of 82±2%. The mean fat and protein contents were 0.6±0.5% and 1.8±2%, respectively. The mean carbohydrate content was 15.2±3%, and the ash content ranged from 0.5±0.1% to 0.5±0.8%. There were no significant changes in the L* values (denoting lightness) during storage. The a* value (redness) showed no appreciable decline, but the b* values (yellow) reflected a decline, and a shift in the yellow color. In general, firmness decreased as storage time increased for the HSP. Overall, the chemical characteristics of the HSP are comparable to those reported for various cultivars of field sweetpotatoes. The judges described the HSP as too bland and too rough, but these attributes could be treated.