The smell of coffee according to its source is of great reference value for roasting.

Classify the smell of coffee by source

According to the source, the aromatization table can be divided into three groups:

Group 1: these compounds are the result of enzymatic reaction during the growth of coffee beans. The main components are ester and aldolase. This compound is the most volatile and is often found in the dry aroma of freshly ground coffee powder.

The first group can be further subdivided into three types: flower flavor, fruit flavor and grass flavor.

The first group of enzyme by-products (the most volatile aromatic components)

1. Fragrance of flowers

1. Floral smell

A, sweet flower ignorance (Riley flower, Arnica lavender. Coffee flower

B sweet grass flavor (pyrola, camellias)

2. Fragrance

A sweet spicy taste (cardamom, cinnamon. Sandalwood)

B parsley (parsley, dill. Green mint)

C sweet camphor (sweet basil, tarragon, coriander seeds)

D fennel flavor (anise, fennel, etc.)

Second, fruit aroma

1. Citrus flavor

A sweet orange flavor (lemon, orange, orange)

B dried orange (grapes, apples and olives)

two。 Berries

A sweet pulp fruit (cherry, apricot, strawberry, jujube)

B dried berry flavor (blueberry, black cherry Boyson hybrid plum)

Third, grass flavor

1. Allium plants

An Onion flavor (onion, chive)

B garlic {garlic, leek, ferulae}

2. Legumes

A vegetable flavor (pea, spinach, cabbage)

B parsley (parsley, alfalfa mu, cucumber)

The second group: the shape of this group of aromatic compounds is the result of caramelization in the roasting of coffee beans. The second group can be further subdivided into chestnut, caramel and chocolate.

The second group of compounds have moderate volatilization. It is usually felt in freshly brewed coffee and in the water vapor that enters the nasal cavity when swallowing coffee. This group of fragrance c acetaldehyde, ketose carboacylation table, p-diazobenzene table) plus various taste characteristics constitute the main taste characteristics of all kinds of coffee beans. This is the main means to distinguish coffee beans from similar producing areas from those from other producing areas.

The appearance of various by-products after caramel reaction depends entirely on the roasting process of coffee. Normally。 Acetaldehyde ketones first appeared in the baking process. Shallow roasted coffee beans have obvious nutty flavor. With further baking, the sugar molecules in the beans will be condensed into a mass of brown-yellow substance-caramel. It contains heterocyclic compounds, sulfonamides and alcohol.

So。 Standard roasted coffee. It usually has the characteristic of caramelization. Further heating will reduce the content of caramel in coffee and form p-diaminobenzene compounds. So。 Thoroughly roasted coffee will have a chocolate-like smell. If you continue to heat. A series of by-products that burn off caramel. So。 The deeply roasted coffee no longer has the odor characteristics of the second group.

Roasted coffee no longer has the odor characteristics of the second group.

The second group of caramel by-products

{moderately volatile aromatic components)

one。 Nutty (most common in lightly roasted coffee beans)

1 nutty flavor (baked nutty flavor)

a. Almond flavor

B Peanut ignorance

C walnut flavor

2 malt (baked grain)

A fragrant rice

B Barley flavor

C Corn flavor

D roasted coffee

E toast

two。 Caramel (most common in standard roasted coffee beans)

1. Candy class

A toffee sugar flavor (including butter)

B licorice flavor (taixin spice)

C lactulose flavor (containing salt)

D nut sugar ignorance

E hazelnut sugar flavor

2 syrup

A sugar ignorance

B Maple syrup flavor

C honey flavor

three。 Chocolate (more common in fully roasted coffee beans)

1. Chocolate (with bitterness)

A baked chocolate

B Dutch chocolate

C dark chocolate ignorance

2 vanilla (including butter)

A Swiss chocolate flavor

B creamy taste

C butter flavor

The aromatic compounds from the third group of coffee bean fibers formed the third group of chemicals. The main components of this group of compounds are heterocyclic compounds, nitriles and hydrocarbons are also the least volatile aromatic components. This smell is often found in the aftertaste of freshly brewed coffee. It can be further subdivided into three types of turpentine. Spices and charcoal.

The third group of dry distillation by-products (the least volatile aromatic components)

1. Turpentine

1 resin texture

A pine tree (pine sap, pine oil hemlock bark

B balm grease (juniper, mahogany and chicory)

2 drug taste

A cinoelic (oregano, rosemary eucalyptus leaves

B camphor (camphor, eggplant, yarrow)

Second, spices

1 Fever type

A nutmeg (nutmeg, celery seed, cumin, cedar)

B peppers (black pepper, ginger)

3 spicy

A cloves (clove buds, sweet peppers. Laurel leaves)

B thyme (thyme, mint, vanilla)

C. bitter almonds (bitter almonds, peach kernels)

three。 Carbon

1. Smoke ignorance

A, methoxycresols (oil, tar, fat)

B Tobacco (tobacco, nicotine)

2. Gray taste

A, burning type (paste taste, burning taste)

B, charcoal burning (charcoal burning, ash)

Source: network