Variability of Free Sugars, Organic Acids and Capsaicinoids in Capsicum baccatum

Variability in the concentrations of free sugars, organic acids and capsaicinoids that contribute to fruit flavor in Capsicum baccatum is not well understood.  We evaluated mature green fruit of >230 non-cultivated and cultivated accessions of C. baccatum var. baccatum and C. baccatum var. pendulum acquired from the USDA/ARS Capsicum genebank in Griffin, GA.  Concentrations (mg/100 mL juice extract) of sucrose, glucose and fructose in fruit ranged from 0 (not detected) to 451, 177 to 3,012, and 38 to 1,241, respectively, with associated median values of 5, 1,154 and 541.  Total sugar concentration ranged from 0.3 to 4.0% with a median value of 1.7%.  Concentrations of organic acids ranged from 20 to 2,016, 0 to 86, and 0 to 457 mg/100 mL juice extract for citric, malic and isocitric acids, respectively, with associated median values of 477, 35, and 8 mg/100 mL extract.  Citric acid was generally the predominant acid among accessions.  Concentrations of capsaicinoids among accessions ranged from 0 to 8,961, 7,858, 680, 752, and 324 mg/g dry weight for capsaicin, dihydrocapsaicin, nordihyrocapsaicin, homocapsaicins and homodihydrocapsaicins, respectively, with associated median values of 2,063, 888, 180, 71, and 35 mg/g dry weight.  Capsaicin was generally the most abundant capsaicinoid.  Pungency among accessions ranged from 116 to 214,531 Scoville heat units/g dry weight with a median value of 55,300.  Variability in the concentrations of free sugars, organic acids and capsaicinoids is sufficiently large that genetic manipulation may enable the development of improved C. baccatum cultivars with novel flavors and the introgressions of desirable flavor attributes into bell pepper (C. annuum) breeding lines.