No abstract

A muscadine grape (Vitis rotundifolia) planting was established in 1996 at the Southwest Research and Extension Center in Hope, Ark., to provide information on the performance of muscadine grape cultivars in a region where cold hardiness is not a major limitation. This research evaluated harvest parameters, fruit and juice quality, and nutraceutical potential of selected muscadine cultivars grown in southwestern Arkansas. The cultivars evaluated were `Black Beauty', `Carlos', `Cowart', `Doreen', `Early Fry', `Fry', `Granny Val', `Ison', `Jumbo', `Late Fry', NC67A015-17, NC67A015-26, `Nesbitt', `Scarlett', `Southern Home', `Sterling', `Sugargate', `Summit', `Supreme', and `Tara'. Muscadine cultivars differed in productivity and fruit quality. In 2002 and 2003, juice was produced from `Carlos', `Granny Val', `Ison', `Nesbitt', `Southern Home', `Summit', and `Supreme' grapes. `Black Beauty' was also produced into juice in 2003. In 2002, `Nesbitt' grapes had the highest juice yield, 520 L·t–1 (124.6 gal/ton). `Ison' and `Supreme' juice had the highest soluble solids level. In 2003, `Granny Val' grapes had the highest juice yield, 551 L·t –1 (132.0 gal/ton). `Southern Home' juice had the highest soluble solids. The press materials of muscadine grapes were a potential source of high levels of nutraceutical compounds. Dried seeds had the highest total phenolic and oxygen radical absorbance capacity (ORAC) levels followed by the dried skins, the grapes, and then the juice. The skins of the black cultivars had the highest total anthocyanins level. `Supreme' seeds had the highest total phenolic and ORAC levels while `Ison' skins had the highest total anthocyanin levels. Based on yield, harvest, and juice quality, cultivars recommended to growers in southwestern Arkansas and other areas with a similar climate include `Black Beauty', `Carlos', `Fry', `Granny Val', `Nesbitt', `Southern Home', `Summit', and `Supreme'.

Muscadine grapes (Vitis rotundifolia Michx.), native to the southeastern United States, have a distinct flavor, and grocers are interested in marketing them as table grapes. Two studies using 'Fry' muscadines were conducted to assist the muscadine industry in providing quality table grapes. Study 1 (1998 and 1999) evaluated density sorting and relationships between maturity, color, soluble solids, firmness, shelf life, and sensory evaluation of grapes. Study 2 (1998) determined the effect of storage on quality attributes of different maturities of grapes and evaluated use of polyethylene bags to extend their storage. Density separation successfully sorted grapes by maturity. Muscadine berry color may allow for visual or electronic sorting to eliminate immature fruit. Sensory panelists could distinguish differences in maturities for all sensory attributes. In 1999 maturities 3 and 4 (≈24-33 soluble solids: acid ratio) were preferred overall by panelists. As maturity increased, soluble solids and pH increased, and acidity decreased. Firmness decreased as maturity and storage at 2 °C increased. Percent decay increased with maturity and storage time. Grapes stored in polyethylene bags had reduced decay. A chart developed from the 1999 data related berry color to soluble solids: acid ratio, soluble solids, tartaric acid, and pH. Data from these studies can be used by industry to establish harvest parameters and enhance marketability of 'Fry' muscadine grapes.

Procedures designed to improve fruit firmness of overripe strawberry fruit originally designated for the fresh market were investigated.

Red wine is composed of a complex matrix of compounds that can interfere with analysis. A high-performance liquid chromatography (HPLC) procedure was developed to efficiently analyze organic acids, sugars, glycerol, and ethanol in Cynthiana (Vitis aestivalis) wine. Standard laboratory procedures (pH, titratable acidity, and color attributes) and HPLC were found reproducible for Cynthiana wine. HPLC recovery efficiency was determined by analysis of spiked and unspiked samples (model, Cynthiana, and Syrah (Vitis vinifera) wines). Although recovery of components was greater in the model wine, recovery in Cynthiana and Syrah wine was comparable. The HPLC procedure was further compared to commercial rapid enzyme analysis tests using model, Cynthiana, and Syrah wines. HPLC analyses were more accurate than enzymatic tests for determining components in the model, Cynthiana, and Syrah wines. Considering the complexity of the wines analyzed, reproducibility and recovery of the HPLC procedure was demonstrated and showed improvement and precision when compared to existing methods.