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Influence of roasting levels on ochratoxin a content in coffee.

Santina Romani¹, Gian Gaetano Pinnavaia, Marco Dalla Rosa

¹Corso di Laurea in Scienze e Tecnologie Alimentari, Dipartimento di Scienze degli Alimenti, Via Ravennate 1020, Università di Bologna, 47023 Cesena, Italy. santina@kaiser.alma.unibo.it

Journal of Agricultural and Food Chemistry

|August 9, 2003

Summary

Roasting coffee beans significantly reduces ochratoxin A levels, especially in highly contaminated samples. Roasting severity and initial ochratoxin A content influence reduction, with espresso roasts achieving over 90% elimination.

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Area of Science:

Food Science
Mycotoxicology

Background:

Inconsistent findings exist regarding ochratoxin A (OA) reduction during coffee roasting.
Understanding OA elimination is crucial for coffee safety.

Purpose of the Study:

To investigate the elimination of ochratoxin A during coffee roasting.
To correlate OA reduction with roasting parameters and initial contamination levels.

Main Methods:

Four naturally OA-contaminated green coffee samples were roasted under light, medium, and dark conditions.
Roasting parameters (weight loss, color, density, moisture) and OA content were analyzed.

Main Results:

Roasting significantly reduced ochratoxin A content in all samples.
Higher initial OA levels and more severe roasting led to greater reduction percentages.
Espresso roasting conditions achieved >90% OA reduction, irrespective of initial contamination.

Conclusions:

The roasting process effectively eliminates ochratoxin A from coffee beans.
Roasting severity and initial OA concentration are key factors in mycotoxin reduction.
Standard espresso roasting protocols ensure substantial ochratoxin A reduction, enhancing coffee safety.