Sweet sorghum (Sorghum bicolor [L.] Moench) accumulates fermentable sugars in the stem and is increasingly being
studied as a potential source of feedstock for bioethanol production. The objective of this study was to evaluate biomass
and grain yield in five sweet sorghum cultivars (Dale, M81E, Sugar Drip, Della and Keller) and to determine quality of
extractable juice and grain. Randomized complete block experiments were performed in the summer of 2009, 2010, and
2011. Leaf dry weight varied with year and cultivar and averaged 6177 kg·ha−1
. Fresh stem weight ranged from 21 to 54
Mg·ha−1
with a mean across years and cultivars of 32.9 Mg·ha−1
. Variations in stem weight were correlated with extractable
juice volumes that ranged from 10 to 24 m3
·ha−1
. Juice Brix values fell within a narrow range (14% - 19%)
across years and cultivars with an average of 15.6%. In all production years, theoretical sugar and ethanol yield were
always numerically higher for Keller and M81E. Grain yield was lowest in Keller (90 kg·ha−1
), but ranged from 400 to
1300 kg·ha−1
in other cultivars with a mean of 584 kg·ha−1
across years. However, Keller had the highest starch content
with a lower proportion of resistant starch in the grain. Except for Keller, the cultivars tested are potential sources of
both fermentable sugars and grain.