On behalf of the Seibo NPO, we are pleased to present a research paper, “The Relationship between Acidity and Acid Content in Cold Brew Coffee,” authored by Yuho Suzuki, a high school sophomore volunteer.

This research project was made possible by the Seibo NPO’s sale of Malawian coffee and the generous cooperation of Ataka Trading Co., Ltd. Above all, we would like to express our deepest gratitude and admiration for Ms. Suzuki for her dedication in completing and presenting this research. Thank you so much!

Research Overview
Ms. Suzuki focused on the increasingly popular cold brew coffee, aiming to scientifically elucidate the relationship between its acidity and the amount of acid present (acid content).

Specifically, she roasted coffee beans from Malawi, Kenya, and Guatemala at different levels (light, medium, and dark roasts) and extracted cold brew coffee. She then employed two methods to analyze acidity and acid content: sensory evaluation (human taste testing) and titration (a chemical analysis).

The results revealed the following：

Relationship between Roast Level and Acidity/Acid Content
Lighter roasts exhibited higher acidity and acid content. This is likely due to the breakdown and transformation of acids within the coffee beans during the roasting process.

Regional Differences
Acidity and acid content varied depending on the origin of the beans. Kenyan coffee beans, in particular, showed a tendency toward higher acidity. This is attributable to differences in bean varieties and growing conditions.

Correlation between Sensory Evaluation and Titration Results: A strong correlation was found between sensory evaluation scores for acidity and the acid content measured by titration. This confirms that a higher acid content generally results in a stronger perceived acidity.

Future Prospects
This research’s findings could contribute to optimizing bean selection and roasting methods to improve the flavor of cold brew coffee. It also represents a significant first step toward understanding the relationship between coffee bean origin, roast level, and consumer preferences.

The Seibo NPO has been deeply impressed by the collaborative potential demonstrated in this project, combining the expertise and resources of a supporting company with the inquisitive nature and creativity of a student. We believe that the fusion of corporate knowledge and youthful ingenuity can lead to significantly high-quality research outcomes.

We intend to further develop such collaborations in the future and leverage them to expand our international support activities. The full research paper is available here.