New method makes concord grape juice fresher and tastier

Credit: LWT (2024).

Cornell AgriTech has developed an exciting new process to create fresher and tastier cold-pressed Concord grape juice.

This new method also helps the juice last longer while keeping it full of healthy antioxidants.

The demand for minimally processed, nutritious juices is growing, and this new technique meets that need perfectly.

Traditionally, Concord grape juice is made using hot pressing and thermal pasteurization. While effective, these methods can change the juice’s flavor.

Cold pressing is a better alternative, but it’s challenging because it requires extracting juice without heating the fruit or adding enzymes.

Cornell AgriTech’s groundbreaking research solves this problem by using pulsed electric field (PEF) and high-pressure processing (HPP) technologies.

Professor Olga I. Padilla-Zakour, a co-author of the study titled “Evaluation of Pulsed Electric Field and High Pressure Processing on the Overall Quality of Refrigerated Concord Grape Juice,” published in April 2024, expressed her excitement.

She said, “It’s a wonderful product,” and highlighted the potential for companies to create innovative products using this new process.

The research could also be applied to other juices, especially those from fruits with nutrient-rich skins, like cherries and blueberries.

In the study, grapes harvested from the Finger Lakes region were crushed and treated with electric field pulses.

This treatment created tiny holes in the grape tissue, allowing for efficient extraction of color and nutrients without heat. The juice was then cold-pressed.

The juice samples were refrigerated for 24 hours and then put into flexible plastic bottles for high-pressure processing.

Results showed that PEF significantly improved yield, color, and phenolic content, while HPP extended the juice’s shelf life to at least five months. In contrast, most fresh-squeezed juices only last one to three days in the fridge.

Moreover, the juice processed with PEF and HPP had better antioxidant and anthocyanin levels than thermally pasteurized juice. Anthocyanins are pigments in red and purple foods that offer numerous health benefits.

To evaluate taste, 101 untrained panelists sampled juices processed in three ways: thermally pasteurized, HPP treated, and a combination of PEF and HPP. The panelists rated the PEF and HPP processed juice highest in appearance, authenticity, aroma, and flavor. This suggests that the new technology can help expand the market for premium Concord grape products.

Concord grapes are a significant crop in New York state, with a substantial economic impact. Sam Filler, president of the New York Wine and Grape Foundation, emphasized Cornell University’s vital role in enhancing Concord grape uses, ensuring they remain an important commodity for the state.

This new method offers a promising future for cold-pressed Concord grape juice, benefiting both producers and consumers with fresher, tastier, and healthier juice.