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The National Aeronautics and Space Administration (NASA) Advanced Life Support (ALS) system has selected the sweetpotato as a candidate crop to be grown on long-term space missions. There is limited research regarding the production of sweetpotato bread. The objectives of this research were to: i) determine the chemical properties (moisture, loaf volume, and texture) of bread supplemented with different levels of sweetpotato flour (SPF); and ii) evaluate the structural properties of bread supplemented with different levels of SPF using Scanning Electron Microscopy (SEM) and Differential Scanning Calorimetry (DSC). Bread formulations were supplemented with different levels of SPF, namely: 50% SPF to 50% whole-wheat flour (WWF); 55% SPF to 45% WWF; 60% SPF to 40% WWF; and 65% SPF to 35% WWF. The maximum % strain required to cut the breads into two pieces was used to indicate texture (firmness).

The sweetpotato [Ipomoea (L.) Lam.] has approximately 90% carbohydrate of its dry matter, which makes it ideal for glucose syrup production. However, data regarding the isolation and use of sweetpotato starch (SPS) in syrup production are scanty. The objectives of this study were to: i) develop a syrup from SPS; and ii) determine the physicochemical (refractive index and color), and viscometric properties during storage of the sweetpotato syrup. SPS was isolated from Hillbilly variety field-grown sweetpotatoes. The SPS was rehydrated, heated to 102°C, treated with -amylase at 90°C for five hours, cooled, and further treated with glucoamylase at 62.5°C for 12 hours. The syrup was filtered, evaporated and cooled. The refractive index and color were measured. To determine the viscometric properties of the syrup during storage, the syrups were stored between 21±4°C (room temperature) and 4°C. An AR-2000 Rheometer was used to measure the viscometric properties of the syrup.

This study determined volatile emission from model sweetpotato products using different evaluation methods. Sublimation method and Thermogravimetric Analysis (TGA) coupled to Fourier Transform Infrared (FTIR) were used to assess the volatiles from a Ready-to-eat-breakfast cereal (RTEBC). TGA/FTIR, and Solid-Phase Microextraction Method (SPME) and gas-chromatography mass spectrometry (GC-MS) were used to characterize volatiles in sweetpotato breads (SPB). FTIR peaks at 3500 (alcohols), 2400 (carbon dioxide), and 1900 (ketones) were identified in the RTEBC. For SPME/GC-MS measures, Dimethyl Phthalate (33±0.51), Phenol (39±0.52) and Diazene (48±0.280) were observed in doughs made using different cultivars.

Protein profiles and morphological characteristics of two newly developed sweetpotato varieties (TU-82-155 and J6/66) were compared to a commercial variety (Beauregard) using SDS-PAGE, and SEM, respectively. Under reducing and denatured conditions, electrophoresis displayed the major protein, sporamins, at 25 kDa, for all the three cultivars. No major variability in protein profile or morphological structures, among the sweetpotatoes, was observed. Presence of sporamin was established and total protein was higher in TU-82-155 on a dry weight basis. Starch granules were slightly larger and more sparsely distributed in J6/66.

The objectives of this study were: 1) to isolate starch and process flour from three cultivars of sweetpotatoes, and determine their proximate composition, particle size and crystallinity; and 2) to rank selected appearance, texture and flavor attributes of the sweetpotato cultivars. The mean moisture contents of the starches ranged from 4.4±0.2 to 6.0±0.3%, while color values ranged from 80.9±0.8 to 86.9±0.4. Flours had moisture contents of 3.9±0.1 to 4.3±0.2, and L* values ranged from 82.8±0.2 to 85.0±0.03. The starch granules appeared to be round or oval with characteristic dimensions in the range of 2.6–36.0μm. Consumers ranked the J6/66 as significantly least preferred (p<0.05) than the other two cultivars.