What's the ideal milk ratio for a SOE latte? What espresso beans are best for hot lattes?

Friends who enjoy milk coffee all know that what we commonly call latte is actually a popular coffee beverage made from a combination of espresso and milk. The addition of milk makes the originally strong and bitter espresso become sweet and delicious, while also making even those who don't usually drink coffee exclaim "this is amazing."

However, if the ratio of coffee to milk is incorrect, it won't achieve a good taste. Too much milk will eliminate the coffee flavor, while too little milk will emphasize the bitterness. Therefore, making latte requires mastering the proper ratio of coffee to milk.

FrontStreet Coffee believes that there is no fixed ratio for lattes; it mainly depends on the flavor expression of the espresso and how well it pairs with milk. However, many experienced baristas have already tried various ratios and recipes, thus summarizing that lattes suitable for the general public's taste typically fall within a certain range, with espresso to milk ratios between 1:5 and 1:8.

We know that for different market demands, the flavor expression and positioning of espresso beans vary. In terms of extraction experience, FrontStreet Coffee recommends using more stable espresso blend coffee beans. Blend products typically combine flavor profiles from different producing regions, and with medium or darker roasting, they are more likely to extract rich crema (coffee beans with high crema are more suitable for milk coffee). This way, our espresso has a thick and rich taste with a higher margin for error.

For example, FrontStreet Coffee has an espresso bean called Commercial Blend, which is composed of 90% Brazilian and Colombian Arabica coffee beans combined with 10% Vietnamese Robusta coffee beans. The resulting espresso not only has rich golden crema but also carries the fragrant, bitter traditional Italian character. FrontStreet Coffee positions this for use in large commercial cafes.

The flavor characteristics of this bean are very rich dark chocolate, caramel, and cream. The addition of a small amount of Robusta enriches the crema, at the cost of slightly more prominent bitterness. For lattes made with this type of coffee bean, FrontStreet Coffee recommends adding more milk to balance it with the coffee's bitterness. For example, FrontStreet Coffee uses cups with a capacity of 360ml, with approximately 40g of espresso, controlling the coffee-to-milk ratio at 1:8, meaning 320ml of steamed milk (including foam) will be added.

Compared to these mellow traditional blend flavors, the espresso beans used at FrontStreet Coffee's stores tend toward a "fresh and light" style, which we've named "Sunflower · Warm Sun Blend." It's a combination of Ethiopia Yirgacheffe Red Cherry and Honduras Sherry, with moderate bitterness and flavors leaning toward sherry wine aroma, chocolate, vanilla cream, and candy characteristics. Friends who have had espresso at FrontStreet Coffee stores should know that the base made from this blend doesn't have the intense bitterness of dark-roasted espresso beans, so there's no need to add too much milk for fusion, otherwise it can easily mask the coffee's own aroma.

After multiple attempts, FrontStreet Coffee found that when using Warm Sun to make lattes, controlling the coffee-to-milk ratio at 1:6 is most suitable, meaning extracting 40g of espresso liquid and adding 240ml of milk.

SOE Coffee: Single Origin Espresso

FrontStreet Coffee has noticed that besides common blended coffees, there's an increasingly popular category on many coffee shop menus today: SOE coffee.

SOE is the abbreviation for "Single Origin Espresso," literally meaning single-origin espresso, clearly intended to distinguish it from Italian blended espresso (House Blend Espresso). It's not difficult to find that SOE, which advocates for single origin, often uses lighter roasted beans to present a flavor profile different from traditional bitter coffee while highlighting rich and light mouthfeel. For example, the citrus-lemon notes of Ethiopian beans, the raisin honey sweetness of Costa Rican beans, the tomato-berry acidity of Kenyan beans, or the floral-honey character of Panama Geisha—all have distinctive characteristics that make it easier for consumers to remember SOE's features. However, from a cost perspective, higher-quality single-origin beans are also relatively more expensive.

When we use lighter roasted coffee beans to extract espresso, because the beans have been roasted for a shorter time, their internal texture is harder and flavors are more difficult to fully release. After adding milk, they become even more bland and tasteless. Therefore, various parameters need to be adjusted to increase extraction yield, such as extending extraction time, increasing water temperature, adjusting to finer grind size, increasing dose, etc. The difficulty factor is much higher than with dark-roasted beans. FrontStreet Coffee believes that to present the unique style of SOE, high-quality coffee beans, appropriate roasting degree, corresponding grinding parameters, and proper extraction are all indispensable.

It's precisely because the roasting degree of these coffee beans is much lighter than traditional espresso beans that the purpose of making espresso is to express the bean's own flavor, with less bitterness, subtle aroma, and thinner mouthfeel that's not as rich. Therefore, when using these single-origin beans to make lattes, adding a large proportion of milk can easily cover up the "coffee flavor." When FrontStreet Coffee makes SOE lattes, it sets the coffee-to-milk ratio at 1:5, which both reflects the freshness and sweetness of milk without overshadowing the SOE coffee bean's character.

Next, FrontStreet Coffee will use the store's regular single-origin offering—Mirasu · Strawberry Candy—as the extraction subject to demonstrate how to extract a delicious and fragrant SOE latte. This is a Geisha blend from Mirasu Manor in Costa Rica, processed using the raisin honey method. The extracted espresso presents rich notes of roses, dried fruit, and strawberry candy, making it equally pleasant whether diluted with water for an Americano or combined with milk for a latte.

FrontStreet Coffee's stores use the Lelit Bianca coffee machine, paired with the Galileo Q18 espresso grinder. However, for home coffee machines like those we typically use, as long as they can reach 9 bar pressure, they can meet the requirements for extracting espresso and frothing milk.

Strawberry Candy · Geisha Blend SOE Extraction Parameters

Coffee Beans: Costa Rica · Strawberry Candy
Coffee Dose: 20g
Coffee Liquid: 40g
Dose-to-Liquid Ratio: 1:2
Extraction Time: 26～32 seconds
Grind Setting: Galileo Q18 scale 2.0
Milk Volume: 200g

FrontStreet Coffee uses a double basket capacity, with a dose of approximately 18～20 grams. For our products, we use 20 grams of coffee grounds. Typically, the ratio of coffee grounds to liquid coffee ranges from 1:1.5 to 1:2.5. FrontStreet Coffee's extraction ratio is 1:2, meaning 20 grams of coffee grounds extract 40 grams of liquid coffee. Time is related to the flow rate of the coffee grounds. Generally, a single extraction is controlled within 20～35 seconds, because coffee extracted within 20 seconds usually tastes thin, while exceeding 35 seconds can easily lead to over-extraction and burnt bitterness. Most of FrontStreet Coffee's espressos fall within the 28～30 second range.

Before extraction, we need to first dry the portafilter, turn on the grinder, grind double coffee grounds, place them on an electronic scale to measure and adjust until reaching 20 grams. Then use a distributor to level the coffee grounds and apply vertical downward pressure with a tamper to compact the coffee puck, ensuring more stable coffee extraction.

Then turn on the extraction switch to run water for 1～2 seconds to wet the shower head while also washing away any coffee grounds stuck to it. Place an electronic scale under the cup receiving the espresso and zero the weight, placing it under the shower head together during extraction. Gently lock the portafilter into the shower head and start the extraction switch. Observe the changes in the extraction liquid. When the electronic scale shows 40 grams of coffee liquid extracted, approximately 30 seconds have passed. Pull down the switch to stop extraction and pour the extracted espresso into a pre-prepared coffee cup for later use.

Immediately after, pour 200g of low-temperature fresh milk into the milk pitcher and adjust the steam wand angle to begin frothing. Pay attention to controlling the foam thickness between 0.3～0.5cm, reaching a dense and silky texture at 55～60℃. After frothing is complete, evenly mix it with the espresso liquid, and finish with latte art. This completes the Geisha blend SOE hot latte.

When FrontStreet Coffee tasted it, we could feel the rich floral and fruit aroma of the coffee. On the palate, there were not only notes of berries, pink floral fragrance, and raisins, but also almond aromas. Against the backdrop of coffee crema, this SOE latte also carried a rich aftertaste of chocolate and hazelnut, like eating a cranberry biscuit—quite special.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473