How to Choose Fresh Coffee Beans_ What Brand of Coffee Beans Is Good_ How to Buy Coffee Beans

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FrontStreet Coffee · "Oily Beans": What They Are and How to Select Fresh Coffee Beans

In the age of online shopping, faced with dazzling products, coffee beans are the key to enjoying good coffee. Buying good coffee beans online definitely requires certain skills. What is the relationship between coffee bean "oiliness" and freshness? Should we choose coffee beans that appear "oily" or "non-oily"? What brands of coffee beans should we buy?

The standards for selecting coffee beans are similar to selecting tea. To get the most expensive and exquisite tea, you need to go to the origin to purchase the highest quality new tea of that year. Coffee is the same - the most premium coffee beans often require you to select them at the variety's origin or entrust specialized foreign suppliers to purchase them.

Therefore, to select good coffee beans, physical store options are relatively limited, while online shopping is an excellent method. So after receiving online-purchased beans, how do you determine if the beans are fresh?

Look

If you're buying single-origin coffee beans, grab about 10 beans in your hand and check if each coffee bean has consistent color, uniform size, and the same shape, to avoid buying inferior products disguised as mixed beans. However, if it's a blend, different sizes and colors are normal. Dark-roast, deep-roasted coffee beans will develop oil. However, if light-roasted beans develop oil, it indicates they have spoiled - not only has their richness decreased, but they will also develop astringent and sour tastes.

Have you seen coffee beans with oily surfaces? Why do some coffee beans appear oily and shiny, while others look "dry and comfortable" without oiliness? What is the relationship between coffee bean "oiliness" and freshness? Should we choose coffee beans that appear "oily" or "non-oily"?

Not Actually Oil - Coffee Oil

The "oil" evenly distributed on coffee bean surfaces is actually not "grease" but a water-soluble organic substance that appears oily. "Coffee oil" itself contains many coffee aromatic components and can dissolve in water, so your brewed coffee won't have a layer of greasy oil floating on top.

Two Reasons Cause "Oily Beans"

Two reasons cause "oily beans": a) Stale light-roast beans b) Fresh dark-roast beans. Let's explore these in depth.

a) Stale Light-Roast Beans

"Light-roast beans" with lighter roasting that appear light brown in color have dry surfaces after roasting and don't develop oil. About five days after roasting (possibly shortened to one or two days during hot summer), they begin showing "spot oiliness" (oil droplets appearing on one side of coffee beans). Please note: a little "spot oiliness" doesn't indicate staleness - sometimes it actually represents light-roast coffee beans at their peak flavor. If they continue to sit, after more than two weeks post-roasting, light-roast beans gradually develop a uniform, thin layer of oil on the surface. They smell not sweet and fragrant, but rather rancid. At this point, the "light-roast beans'" flavor has declined and should be avoided.

b) Fresh Dark-Roast Beans

"Dark-roast beans" with deeper roasting that appear dark brown in color show a slight oiliness immediately after roasting, and begin developing significant "oiliness" from the first to second day post-roast. The shiny appearance of "dark-roast beans" doesn't indicate staleness at all. On the contrary, dark-roast beans' surface oiliness will gradually dry out after three weeks post-roast, eventually becoming dry, stale-tasting beans. Therefore, if you see dry, non-oily coffee beans that appear dark brown, please pay special attention to whether they're marked with a roasting date - they are very likely already spoiled, stale beans.

Even when stale, oily "light-roast beans" will gradually dry out after long periods (such as three months), eventually returning to a dry, non-oily appearance. This shows that surface oiliness is just a reference for judging coffee bean freshness, not an absolute indicator.

First, please purchase from professional coffee roasters who clearly mark dates, have brand credibility, and emphasize fresh roasting. Additionally, excellent coffee packaging bags usually have "one-way degassing valves" (button-like small holes on coffee bags) designed to allow natural carbon dioxide release from coffee beans. Point the one-way degassing valve at your nose, gently squeeze the coffee bean bag, and smell the escaping gas. If it's an intoxicating, rich coffee aroma, freshness is not a problem. Conversely, if it doesn't smell rich enough, or even has a rancid oil smell, this indicates the coffee has long spoiled and should be avoided.

So Why Do Coffee Beans Use Packaging Bags with One-Way Valves?

1. Roasted coffee beans sealed in aluminum foil packaging avoid contact with light and air, preventing rapid aroma dissipation and oxidation.

2. "One-way degassing valve" coffee bags block external light and air from entering, keeping coffee beans in optimal packaging condition and maintaining their fresh, original flavor.

3. Roasted coffee beans naturally release carbon dioxide. If accumulated in the packaging bag, it affects coffee bean quality. The "one-way degassing valve" on the bag allows excess gas to escape, and you can squeeze the packaging bag when selecting to smell the aroma.

This packaging designs a valve with a double-layer structure made of film at the bag seal. After filling with roasted beans, the carbon dioxide produced during roasting escapes through the valve, while external gases cannot enter the bag, effectively preserving the original aroma and essence of roasted coffee beans. This is currently the most recommended packaging method for roasted coffee beans, and you should try to select coffee products with this packaging when purchasing.

To put it more simply, this valve only allows exit, not entry. After coffee beans are roasted, they produce gases like carbon dioxide that need to be slowly released. The one-way degassing valve sealed on coffee bags, with holes punched in the bag surface at the valve position, can automatically release carbon dioxide extracted from roasted coffee beans to the outside of the bag, while external air cannot enter. This effectively ensures the dryness and rich, original flavor of coffee beans, prevents the bag from swelling due to carbon dioxide accumulation, and prevents external air from entering to accelerate oxidation.

Smell

Smell whether the beans have coffee bean aroma. If they do, it indicates the coffee beans are fresh enough. If the aroma is very weak, or even shows a greasy smell similar to old peanuts, it means the beans are completely stale and should not be selected, because no matter how much effort you put in, you cannot brew good coffee from them.

Peel

Peel the coffee beans by hand. If the beans are fresh enough, they will be easy to peel open, accompanied by a crisp sound. If the beans are stale, it will require significant effort to peel them. After peeling, you can check if the roasting degree is uniform. If uniform, the outer skin and inner layer of the coffee bean will be the same color. If the surface color is much deeper than the inner layer's color, it indicates the roasting heat might have been too high, which will also affect the coffee bean's aroma and taste.

Chew

When selecting, it's best to put one or two beans in your mouth and chew them. If the beans are crispy and make a clear crunching sound when chewed, it indicates the beans haven't been exposed to moisture. Additionally, if they leave a lingering fragrance in your mouth, that's top quality!

Whether There Are Sufficiently Rich Bubbles During Brewing

Freshly roasted coffee beans contain large amounts of gas in their bodies and have active respiration. During extraction, the gas released from the beans creates the wonderful, abundant bubbles we see. There's a very fitting descriptive term: "blooming." Yes, when fresh coffee beans are extracted, clusters of rich bubbles are like flowers in this season, blooming. Accompanying this is the rich aroma of fresh coffee beans.

In-Depth Exploration of Bubble Abundance

During extraction, bubble abundance correlates positively with freshness - the fresher, the more bubbles. However, there's a prerequisite here: for the same coffee bean. Specifically, it's the same green beans, same roast, same operation.

Between different coffee beans, or between different roast levels of the same coffee bean, or between different operational parameters of the same coffee bean, bubble abundance will show different performance.

To summarize simply: For the same coffee bean, the fresher it is, the richer the bubbles; for the same coffee bean, dark roast produces richer bubbles than light roast.

[Important Notes]:

Although we can't see the actual product before purchasing and cannot perform selection steps like looking, smelling, peeling, or chewing, when shopping online we can still select from the following aspects. Of course, these aspects also apply to physical store selection.

A. Origin

Online, some stores might use coffee beans not from their declared origin. For example, some might be Blue Mountain coffee, but their origin isn't Jamaica. However, this doesn't mean non-origin coffee is necessarily bad. Due to different climates, the taste might vary slightly. Often, non-origin coffee is cheaper. If you're not overly particular, trying flavors from different origins is also acceptable.

B. Packaging Date

Pay attention to whether the packaging date is recent. Generally, green coffee beans have a shelf life of one to two years, while roasted beans' freshness period is within one month. Therefore, to select freshly roasted coffee beans, use them within their freshness period after purchase to enjoy coffee's most enchanting aroma and rich taste.

C. Store and Brand

This goes without saying - some coffee might mix with other types to reduce costs. So be careful. For example, mixing cheap coffee beans in expensive ones, or mixing poor-quality coffee beans of the same variety with good-quality ones will seriously affect the taste. So when buying coffee beans, try to choose guaranteed stores or brands, or check online user reviews.

END FrontStreet Coffee: A Guangzhou roastery with a small storefront but diverse bean varieties, where you can find various famous and lesser-known beans. They also provide online store service. https://shop104210103.taobao.com

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473