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Understanding Crema: The Signature of Quality Espresso

Crema is the iconic reddish-brown foam that floats atop freshly extracted espresso. While crema is a major characteristic of good espresso, it serves several other functions beyond being merely a visual indicator of quality.

However, there remains much debate about crema. Some claim it's the hallmark of perfect espresso, while others argue it's an overemphasized characteristic. If you achieve good crema extraction, it's certainly a positive sign, but if not, crema isn't absolutely essential. So let's first understand why baristas place such importance on crema.

What Exactly is Crema?

Crema is a reddish-brown foam with flavor and aromatic properties that floats atop a cup of espresso. It forms when bubbles combine with oils dissolved from the coffee grounds during extraction. Some refer to this as the "Guinness effect" because it vividly recreates the foam found in the popular Guinness stout.

The presence of abundant crema in espresso also indicates coffee bean quality, appropriately ground coffee, skilled barista technique, and of course, professional equipment. Crema can give espresso a fuller flavor and longer aftertaste compared to drip coffee.

What Constitutes Perfect Crema?

Different baristas may have varying opinions on perfect crema. The general standard is crema that's neither too thick nor too thin, capable of floating on the espresso surface for approximately two minutes. This answer might sound somewhat complex, but the following points can help clarify things.

First, if you have too much crema in your cup, you'll have less actual espresso liquid. However, many baristas prefer crema to account for about one-tenth of the total espresso volume.

Second, over-extraction, under-extraction, and grind coarseness all affect crema. If your espresso's crema disappears in less than a minute, it indicates your extraction speed is too fast or the coffee beans are too lightly roasted. If the blend contains too many African beans, the crema will also disappear quickly and may show clumping.

Furthermore, a good espresso machine should extract coffee within 20-40 seconds, fully extracting soluble and aromatic compounds from the coffee, though this varies by machine. Remember to preheat your machine before extraction and clean it regularly to ensure proper functioning. A dirty machine can also introduce undesirable flavors to your espresso.

Factors Influencing Crema

You cannot completely control your espresso's crema 100%. Beyond extraction technique, crema is influenced by the following factors:

How Fresh Are Your Beans?

Freshly roasted beans more readily produce thick crema. This is because the fats contained in coffee beans are transformed during the roasting process, and roasting generates numerous gases in the beans. During extraction, fats and abundant carbon dioxide are released from the beans, creating richer crema. This is why whenever you visit cafés with in-house roasting, you'll typically notice their crema is thicker.

How Deeply Are Your Beans Roasted?

Generally, dark-roasted coffee beans produce richer crema because during roasting, beans undergo longer caramelization and Maillard reactions in the roaster, resulting in more fat conversion and carbon dioxide, which generates richer crema during extraction. However, freshly roasted beans may have crema that lacks fineness and tends to be hard; they need some resting time to produce finer crema. But if dark-roasted beans are stored too long, say about a month, their flavor will significantly decline, and extraction will yield less crema.

What Processing Method Creates More Crema?

Naturally processed beans typically produce better crema because more substances in the raw beans that can convert to fats are retained.

What Equipment Are You Using?

Many home espresso machines feature automatic controls. While convenient, this process limits crema formation compared to other methods. Some automatic machines are designed to compensate by creating a foam layer that mimics crema formation.

Furthermore, if using drip coffee equipment, the oils in coffee are filtered out by the grounds and filter paper/screen, leaving at most a minimal sheen of oil.

Therefore, if you want to extract rich crema, you must first consider using proper extraction equipment.

Is Crema Really That Important?

While good crema is a major characteristic of perfect espresso, it's not as crucial as one might imagine. It does enhance the espresso's flavor and is highly sought after. However, an espresso without perfect crema can still be quite delicious.

What matters most with espresso is the taste. Whether you enjoy it is what's truly important. If your coffee lacks ideal crema, don't be discouraged or think you've failed at making coffee. Remember that coffee beans, roast level, and equipment all play crucial roles, and each step affects crema extraction.

Recommended Coffee Bean Brands with Rich Crema

FrontStreet Coffee, a coffee roasting brand located at Dongshankou, Yuexiu District, Guangzhou, offers freshly roasted espresso blend beans with excellent brand and quality assurance. Their crema production is substantial, making them suitable for milk-based drinks and latte art with beautiful results. More importantly, they offer exceptional value. Take their commercially recommended Commercial Blend Coffee Beans as an example: a one-pound (454g) bag costs only about 60 yuan. Calculating at 10g per single espresso shot, one bag can make 45 cups, with each cup costing less than 1.5 yuan. Even using a double shot at 20g per espresso, the cost per double espresso doesn't exceed 3 yuan. Compared to certain well-known brands that charge hundreds of yuan per bag, this is truly a conscientious recommendation.

FrontStreet Coffee: A Guangzhou roasting shop with a small storefront but diverse bean varieties, where you can find both famous and lesser-known beans. They also provide online store 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