- Winter 1996 "Update" Newsletter Article -
Juice for concentrate
Initial study results indicate Concord-type cultivar may be suitable for production, processing in California
From CATI Publication #960101
Copyright © 1996. All rights reserved.
Grapes grown specifically for juice concentrate production in the San Joaquin Valley may one day become a common sight as a result of research being conducted at California State University, Fresno.
Scientists at the Viticulture and Enology Research Center (VERC) have released preliminary data showing that at least one new variety grown in the San Joaquin Valley may be able to match the quality standards of red Concord grapes grown in the temperate climate regions of Washington and New York states.
Concord remains the preferred variety for use in the expanding juice concentrate market, report the researchers, which include associate Katherine Haight, chemistry professor Barry Gump and scientist Keith Striegler. However, the hot, dry climate of California's San Joaquin Valley adversely affects the growth, yield and fruit composition of Concord grapevines. Production results in this area "have been uniformly disappointing," the researchers note.
That has provided the impetus for development of new varieties for the central California region. So far five have been tested in a research project begun at Fresno State in 1993. The varieties include Sunbelt, released as a new juice grape from the Arkansas Agricultural Experiment Station in 1993, as well as Cloeta, R.W. Munson, Bailey and Extra, all developed in the early 1900s by breeder T.V. Munson.
Various processing methods were used to extract juice from the experimental varieties, including hot pressing, cold pressing, and freezing before cold pressing, Haight said.
Of the five tested, hot pressed Sunbelt produced the most intense color, comparable to the color of Concord grapes grown in Washington and New York. Phenolic levels of Sunbelt also were similar to those of the Concord varieties, test results show.
"The concord-type experimental cultivars have potential in vineyards as high color, high sugar, low maintenance grapes," the researchers said. If some of these cultivars prove viable for this region's climate, it's possible that some growers could plant specifically for the concentrate market.
A number of economic research institutes, such as the International Trade Centre in 1992, have concluded that the fruit juice business would remain a growth industry as foreign consumers become more "health conscious" and change their eating and drinking habits.
Some of the varieties included in this study, along with other new ones, will be produced from a "concentrate vineyard" being established as part of the concentrate project, funded in part by the California Agricultural Technology Institute (CATI).
The preliminary report, entitled "Evaluation and Characterization of Concord-type Grape Juice Concentrates from the San Joaquin Valley," was recently published by CATI and can be requested by using the form on Page 7.
For more information on the project, the researchers can be contacted through VERC by calling (559) 278-2089.{ page top }