Why Grinding Coffee Beans Fresh is Essential for Quality Coffee

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"Buying a coffee grinder is better than buying a package of premium coffee powder." Lin Zhehao, a certified appraiser of the International Coffee Quality Institute, suggests that coffee enthusiasts buy roasted coffee beans to store at home, grind them fresh for brewing, and keep the storage period as short as possible.

Three factors affect the storage of freshly ground coffee beans: temperature, humidity, and oxidation rate. Lin Zhehao recommends that to taste good coffee, it's best to buy freshly roasted coffee beans. The period from one week to two weeks after roasting will be the best time to taste the coffee. At most, keep it for one month. The longer it's stored, the more likely it is to oxidize and lose flavor, or even develop a rancid taste, making the flavor relatively less enjoyable.

NG Behavior 1: Storing coffee beans in transparent sealed containers exposed to light

Newly roasted beans must be stored in a cool place. The aroma molecules of ground coffee are easily volatile, and the shelf life of coffee is related to packaging technology. Currently common packaging includes sealed bags or bags with one-way degassing valves. One-way degassing bags can better slow down the oxidation rate. Similarly, some people are accustomed to storing coffee beans in sealed containers, and opaque containers are better than transparent ones, as they can avoid light exposure, slowing down the volatilization of aromatic substances and oxidation rate.

NG Behavior 2: Storing coffee beans in the refrigerator to prevent mold

Additionally, coffee beans should never be stored in the refrigerator, whether refrigerated or frozen. The reason is that when you take coffee beans out of the relatively low-temperature refrigerator, there's a temperature difference between room temperature and the bag's interior. Water vapor will attach to the bag's surface, and when opened, water vapor will enter again. Putting it back in the refrigerator will cause it to become damp. If you must store it in the refrigerator, it's best to divide it into portions for use, with one package being the amount for a single use.

NG Behavior 3: Buying beans that smell rancid

To check if the beans stored in a coffee shop are fresh, you can see if there's a layer of oil attached to the appearance of transparent containers. Deep-roasted coffee beans will have an oily sheen, which will dry out over time. Light-roasted coffee beans are the opposite; oil will emerge after prolonged storage. Coffee with a rancid smell also indicates prolonged storage.

Additionally, the freshness of freshly ground coffee beans can be observed during pour-over: relatively stale coffee will have fewer bubbles when poured over, and the coffee grounds will sink. This is because the carbon dioxide in the beans volatilizes faster after grinding, increasing the oxidation rate and causing structural changes. The bubbles that float when water is added are relatively few. This sinking is more easily observed in ground filter bag coffee.

From post-processing to transportation and storage, high-temperature and humid environments are breeding grounds for Ochratoxin A. It's also produced during the transportation of imported corn and soybeans. Han Huaizong, author of "Coffee Science," emphasizes: "You won't be able to see Ochratoxin A on coffee. The toxin is something produced by mold growth and metabolism. Eating mold will not be fatal."

Most commercial raw coffee beans are transported from Central America to Japan for storage and then shipped to Taiwan, which takes about two to three months. If stored at the bottom of the ship's cabin near the motor where temperatures are higher, Ochratoxin A is more likely to be produced. If there are no problems during transportation, they can easily become damp when stacked in warehouses during summer.

To purchase reliable coffee beans, you can find shops within your living area and communicate with the owners of home-roasting stores. Taiwan's home-roasting shops have one of the highest densities globally, making it relatively convenient to choose freshly roasted coffee beans. "Compared to foreign large-scale roasting manufacturers importing packaged coffee beans, small-scale roasters provide beans with higher turnover rates, making them fresher," Lin Zhehao said.

Storing Coffee Beans

When purchasing, choose small packages, don't stock up on beans, buy as much as you drink, and try to speed up turnover.

The shelf life of roasted coffee beans should not exceed one month.

Storing in bags with one-way degassing valves is better than in compressed containers. You can choose opaque containers and place them in a cool place.

If you must store them in the refrigerator, please divide them into independent small bags, with each bag containing the amount for one use.

Recommended Freshly Ground Coffee Bean Brands

The hot-selling freshly ground coffee beans roasted by FrontStreet Coffee (FrontStreet Coffee): Yirgacheffe Coffee, Golden Mandheling Coffee, Brazil Coffee, etc., all have full guarantees in terms of brand and quality. More importantly, the cost-performance ratio is extremely high. A half-pound (227g) package costs only around 70-90 yuan. Calculated at 15g per cup of pour-over coffee, one package can make 15 cups of coffee, with each cup of single-origin coffee costing only about 5-6 yuan. Compared to the price of dozens of yuan per cup sold in coffee shops, this is an extremely high cost-performance ratio.

FrontStreet Coffee (FrontStreet Coffee): A roasting shop in Guangzhou with a small storefront but diverse types of beans, where you can find various famous and lesser-known beans. It also provides online shop services. 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