Abstract
The influence of variety and location on flesh color, pigment content and total carotenoid content was studied using Texas and Colorado grown tubers from ten yellow flesh and two white flesh potato varieties. Antioxidant activity and total phenolics of two yellow flesh and two white flesh potato varieties were also determined. Flesh color was determined using a Hunter Colorimeter. Significant differences were found between the same variety grown in both locations for L* value, chroma, and hue. Texas grown tubers were lighter and redder than Colorado grown tubers, which were more yellow. Colorado tubers were lighter in the center than Texas tubers. Carotene and total carotenoid content of the same potato varieties grown in Texas and Colorado were determined, using BPLC and spectrophotometric techniques. Significant differences were found between the same variety grown in both locations for lutein, zeaxanthin, and total carotenoid content. Lutein and total carotenoids were greater in Colorado grown tubers, while zeaxanthin was greater in tubers grown in Texas. Data from the Hunter calorimeter, BPLC, and spectrophotometer were highly correlated, indicating that either of the three instruments can be used to determine flesh color, carotene and total carotenoid content. Varieties differed in antioxidant activity and total phenolic content. Granola had the highest antioxidant activity and Russet Norkotah the highest total phenolic content, while Yukon Gold had the lowest antioxidant activity and total phenolic content. Differences were slight among tuber parts in antioxidant activity, but they were significantly different in total phenolic content. Skin tissue had the highest antioxidant activity and total phenolic content. These differences in flesh color, carotene content, and total carotenoids were controlled genetically but were influenced by environment.
Al-Saikhan, Mohamed Salem (1994). Genotypic and environmental factors influencing flesh color, carotene content, total carotenoids, total phenolics and antioxidant activity in potato (Solanum tuberosum L.). Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1994 -THESIS -A4615.