Acidity and Bitterness

There are several chemical and physiological factors that can modulate taste sensation and perception. The course ‘Acidity and Bitterness’ will focus on these two taste qualities since they are central in coffee quality.

Acidity and Bitterness - Course Facts

Time: Two-day course, 9.30 am – 4.30 pm

Included: Lunch, course material, certificate

Instructor: Fabiana Carvalho, PhD

Course language: english

Requirements: profound knowledge about sensory in coffee or any other foods

Target audience: Cuppers, Sommelières, Producers, Roasters, Green Coffee Buyers

Acidity and Bitterness - Course Description

Sour is a basic taste that can be perceived as pleasant but can become highly unpleasant depending on intensity and absence of other tastes. It is important to understand the distinction between the concepts of ‘acidity’ and ‘sourness’ (or perceived acidity). Bitter can be considered the most complex taste quality, based on both the wide variety of bitter tastants and on the large number of genes encoding bitter receptors. The course will discuss, based on scientific evidence, the presence of sour- and bitter-tasting compounds in coffee as well as individual variability in sour and bitter perception.

DAY 1 – ACIDITY (9:30am-4:30pm)

THEORY

• The taste on the tongue and the taste in the brain: What is a gustatory perception?
• Individual sensitivity to sourness: Genes, saliva, and hormones.
• Acids in coffee: Acidity vs. Sourness.
• Sourness in context: Basic tastes interaction and crossmodal effects

PRACTICE

• The sourness of different types of acids.
• Individual sensitivity to different types of organic acids.
• Interaction with other basic tastes.
• Crossmodal effects of smell and colour on the perception of sourness.

DAY 2 – BITTERNESS (9:30am – 4:30pm)

THEORY

• The fifty shades of bitter: Genetics and environment.
• Individual sensitivity to bitterness: Genes, saliva, hormones, and preferences.
• Different classes of bitter compounds
• Bitterness in coffee: Flavoromics, or putting the chlorogenic acids in context.

PRACTICE

• Individual sensitivity to different classes of bitter compounds: Beyond the caffeine standard.
• What is a ‘supertaster’?
• Interaction with other basic tastes.
• How bitter is your coffee? Crossmodal effect of smell on the perception of bitterness.

Acidity and Bitterness - Your Trainer

Fabiana Carvalho is a neuroscientist who received her MSc in Biochemistry and her PhD in Psychobiology studying neural processes of perception and memory. She has also worked as a postdoctoral researcher on a project investigating sensory perception as an anticipatory and constructive process instead of a mere passive and reactive process.

She is currently a collaborating researcher at the University of Campinas, Brazil. Her research project “The Coffee Sensorium” is focused on understanding multisensory flavour perception and how it impacts the coffee drinking experience. She has published several scientific articles showing the effect of coffee cups and packaging on sensory and hedonic judgements of specialty coffee. This research project has several collaborators such as the SCA (Specialty Coffee Association) and Prof Charles Spence (University of Oxford, UK).