@article{truong_hu_thompson_yencho_pecota_2012, title={Pressurized liquid extraction and quantification of anthocyanins in purple-fleshed sweet potato genotypes}, volume={26}, ISSN={["1096-0481"]}, DOI={10.1016/j.jfca.2012.03.006}, abstractNote={Analysis of anthocyanins responsible for the purple flesh color is important for breeding programs and development of value-added products. This study aimed to optimize the conditions for anthocyanin extraction from purple-fleshed sweet potatoes (PFSP) using pressurized-liquid extraction (PLE) method and quantify anthocyanins in various genotypes. Freeze-dried powders of PFSP genotypes were extracted with acidified methanol using an accelerated solvent extractor. Anthocyanin content of the extract was characterized by (a) pH-differential method and (b) color value protocol measuring absorbance at 530 nm, which is commonly used in Japan as a commercial indicator of total anthocyanin quantity. Highest anthocyanin yields by PLE were with an acetic acid:methanol:water mixture of 7:75:18% (v/v), sample weight of <0.5 g and 80–120 °C. Among 335 genotypes, the anthocyanin content varied widely from 0 to 663 mg cyanidine-3-glucoside equivalent/100 g powder or 0–210 mg/100 g fresh weight. The total monomeric anthocyanin (TMA) contents determined by the pH-differential method were highly correlated with the Japan color value (JCV) protocol, TMA = (0.145) JCV, R2 = 0.943. These results can be useful for sweet potato breeding programs and processing industry in development of PFSP cultivars and processed products with high anthocyanin levels.}, number={1-2}, journal={JOURNAL OF FOOD COMPOSITION AND ANALYSIS}, publisher={Elsevier BV}, author={Truong, V. D. and Hu, Z. and Thompson, R. L. and Yencho, G. C. and Pecota, K. V.}, year={2012}, pages={96–103} }
 @article{thompson_fleming_hamann_monroe_1982, title={METHOD FOR DETERMINATION OF FIRMNESS IN CUCUMBER SLICES}, volume={13}, ISSN={["0022-4901"]}, DOI={10.1111/j.1745-4603.1982.tb00886.x}, abstractNote={ABSTRACTA punch and die assembly was adapted to the Instron UTM for deter‐mination of firmness of mesocarp and endocarp tissues in cucumber slices. A cylindricalpunch 0.315 cm diameter (0.200 to 0.635 cm diameter tested) and a cucumber slice thickness of at least 0.48 cm were found to be suitable for the method developed. Penetration force was about five times greater for mesocarp than endocarp in 4 to 5 cm diameter cucumbers. Mesocarp and endocarp were firmer near the stem end than near the blossom end of cucumbers. Force readings also declined for both tissues with increase in fruit diameter from about 2 to 6 em. Single slices taken from the center of 20 cucumbers and punched once each at specified locations in the mesocarp and endocarp provided sufficient sampling to limit the coefficient of variation to about 5%. The correlation coefficient between sensory analysis for firmness and puncture force readings of fermented cucumber slices was 0.88.}, number={3}, journal={JOURNAL OF TEXTURE STUDIES}, author={THOMPSON, RL and FLEMING, HP and HAMANN, DD and MONROE, RJ}, year={1982}, pages={311–324} }