NEW ORLEANS -- Thanks to charismatic enzymes and environmental concerns, the brine from processed sauerkraut no longer may pose an ecological threat. Instead, it could cut the mustard as a popular flavor enhancer for a variety of beverages and foods, according to a Cornell University scientist. Sauerkraut brine is the byproduct generated in the fermentation of cabbage. When the brine is poured into sewers or other tributaries, it becomes a pollutant since it robs the water of oxygen. It has high biochemical oxygen demand (BOD), and large amounts of lactic acid and salt, thus contributing to environmental degradation.
But Cornell scientists have found a solution to the pollution. By adding a yeast known as Candida wickerhamii, the brine is neutralized of the oxygen-stealing organic matter. The yeast uses most of the biochemical oxygen demand. After adding the yeast to the brine, a very useful enzyme, Beta-glucosidase, results, according to Yong D. Hang, professor of food science at Cornell's Agricultural Experiment Station in Geneva, N.Y.
"Yeast loves the sauerkraut brine," Hang said. "The yeast can assist the food processors in preventing environmental degradation and at the same time produces value-added products."
Shyh-Liang Sim, graduate student in food science, and Hang are presenting their research in a poster session, "Optimization of b-Glucosidase production by Candida Wickerhamii from Sauerkraut Brine Using Response Surface Methodology," at the 1996 Institute of Food Technologists' annual conference, June 25 in New Orleans.
The food scientists can add the b-Glucosidase enzyme to fruit pomace -- the remains of processed fruit -- to extract its exact fruit flavor. The resulting concentrate can add value to such products as apple juice by adding the exact flavors of other fruits, such as natural grape flavoring. In fact, Hang and his colleagues now are working with extracting flavor from concord grapes, the biggest variety of grape grown in New York. Specific fruit flavors can later be added to a wide variety of foods or beverages.
Previous efforts have been made to produce fruit flavors by using acid and heat, but the results were not always desirable, he said.
"Consumers always prefer natural flavors," Hang said. It was hard to extract natural flavors and that is why they were synthesized by chemical means. But, with this type of method, Hang believes that one day it could be less expensive to extract natural flavors than produce them artificially.