What Are Coffee Notes?
The flavours throughout our Idle River Coffee collection are derived from the type of beans we use and the roasting process. The tasting notes on our labels are for descriptive purposes only. You can be assured we never add any flavours or additives to our coffee.
Because everyone’s senses are different, it can often be difficult to identify a coffee’s precise flavour. Like the food we eat, coffee is chemically complex, we experience it through gustation (tasting) and olfaction (sense of smell). When coffee is brewed, it is around 98% water, so the tiny number of dissolved solids, oils, and strong aromatic compounds in the brew, pack quite a punch. Bringing those flavours out is a complex process involving many natural chemical reactions.
GREEN COFFEE
Green coffee refers to the coffee beans in their raw unroasted state, which is how roasters receive them. In the country of origin, coffee goes through a minimum two-to-three-month process to go green. The 'cherry' is picked, de-pulped, fermented, washed, dried, rested, and finally hulled of the parchment layer prior to export, all of which can either enhance or diminish the sensory experience.
The quality of the green bean sets the tone for the rest of the roasting process. If you start with low quality green, roasting it will not transform it into something special. We always work with fresh, high-quality green beans traced directly back to country of origin.
ROASTING
The length and temperature of roasting dramatically transforms acids within the beans as they roast.
Organic acids:
These account for around 7% of the bean and include the prominent chlorogenic acid, as well as citric, malic, phosphoric, quinic, caffeic, acetic, and formic acids. Organic acids add acidity, sourness, bitterness, and astringency. The roasting length dramatically transforms these acids, so a spectrum of flavours can be produced from the same bean.
Balancing the acids is our goal in roasting. If roasted too light, there will be too many remaining chlorogenic acids, so the coffee will taste vegetal and metallic. However, if it is roasted too dark, the tasty acids are lost.
How and where the coffee was grown, determines the acids present.
Higher elevation coffees usually have higher concentrations of acids but it is the natural environment and levels of humidity that determine what acids are present in the bean.
Let’s take a look at the two main components when determining Coffee Notes:
AROMA & TASTE
Aroma
When describing aroma in coffee we can break it down into a few simple categories but understanding what sits in those categories is important. The aroma of a coffee should be considered in juxtaposition to its acidity. Floral notes in coffees may sometimes only be experienced within the context of the aroma. A distinct fresh floral note can easily be distinguished in the aroma.
Enzymatic by-products are related to enzymes reactions in the plant itself and enzymatic reactions during processing.
Sugar browning, as the name implies, is the creation of aromatic compounds during the roasting process by thermal reactions. These include caramel, nutty and toast-like grain aromas.
Dry distillation by-products are related to the burning of plant fibres during roasting. Spicy, smokey and woody aromas are in this group.
Taste
When it comes to taste, we focus the 4 primary taste senses which are Sweet, Salt, Sour and Bitter. We can also add ‘Umami’ into the mix, which is perceived as savoury sweetness like Parmesan Cheese, Mushroom, Walnut etc.
Sweet/sugars: The first sensation humans develop, our appetite for sweetness is unparalleled. In coffee, several sugars (usually called polysaccharides or carbohydrates) exist and are perceived as sweetness. Sweetness in coffee is related to the coffee cherry when picked.
Sour/acidity: We perceive acidity on the tongue as the flavour ‘sour’. The term sour in coffee is related to an excess of acetic acid or tartaric acid due to an over fermentation or unripe coffee. However, our sour receptors also perceive desirable acidity characteristics of fine coffees.
Some of the Acids we taste in coffee are:
Citric Acid: Found in high grown Arabica coffees, these acids lead to citrus flavours like orange and lemon or sometimes grapefruit in a coffee. Some research shows that citric acid is responsible for most of the acid flavours in coffee.
Malic Acid: This can impart more of an apple or pear-like flavour to a coffee, it can also be described as sweet and crisp and have some fruit properties.
Acetic Acid: This is the main component of vinegar, so can be an ‘off’ flavour at higher levels. At lower levels it can have a pleasant sharpness or lime-like flavour.
Tartaric Acid: Tartaric acids are common in grapes and can lead to some wine-like or grape-like notes in a coffee but can also be sour in higher levels.
Salty: Sometimes during coffee tasting, a phantom saltiness can appear which is unrelated to mineral content. Salty flavour is a taste defect in coffee and is usually related to mineral contamination during processing, especially when drying coffee on the ground.
Bitter: Our perception of bitter is thought to be an evolutionary development against environmental poisons. A common alkaloid in coffee is caffeine. Bitterness is essential to coffee’s flavour and not just caffeine but other various products of sugar browning.
Savoury/Umami: In the early 1900’s a Japanese scientist (Professor Kikunae Ikeda) established the taste sensation of umami, (literally translated as ‘deliciousness’) by isolating the flavourful component of Kombu Seaweed. The isolated active component was Glutamic Acid. Glutamic acid is the most common amino acid in food protein. Savouriness in coffee is thought to be related to yeast activity during the fermentation phase of processing.
IN SUMMARY
Coffee’s flavour is a combination of its taste perceived on the tongue and a myriad of aromatics perceived in the nasal cavity. The more a coffee taster tastes, the more skilled he/she becomes in the art of tasting in general and therefore, more able to articulate the subtle nuances of coffee notes.