Coffee FAQ: 15 Questions Every Coffee Drinker Asks

Whether you're new to specialty coffee or you've been grinding your own for years, some questions come up again and again. Here are the ones we hear most — with honest answers rather than waffle. ## 1. What's the difference between Arabica and Robusta?

1. What's the difference between Arabica and Robusta?

They're the two main species of coffee bean, and they taste quite different.

Arabica grows at higher elevations, has a sweeter and more complex flavour, brighter acidity, and less caffeine (about 1.5%). It's what most specialty coffee is made from.

Robusta grows lower down, tastes stronger and more bitter, has roughly double the caffeine (about 2.7%), and is generally cheaper. You'll find it in a lot of instant coffees and espresso blends where a bit of extra punch is wanted.

Most of our Raw Bean range is Arabica — we're after flavour and complexity rather than a caffeine hit.

2. How should I store coffee beans?

Airtight container, cool dark cupboard. That's the short version.

The longer version: keep coffee away from light, heat, moisture, and anything with a strong smell. Don't put it in the fridge — coffee absorbs odours, and the moisture doesn't help. If you want to freeze whole beans for the long term, seal them properly and don't keep taking them in and out.

Whole beans last longer than pre-ground. All our coffees are nitrogen-flushed during packaging to remove oxygen, which helps keep things fresh from the moment you open the bag.

3. What's the best water temperature for brewing?

Between 90 and 96 degrees Celsius. Too hot and you'll pull out bitter compounds. Too cool and you'll get a flat, under-extracted cup.

If you don't have a temperature-controlled kettle, just let a freshly boiled kettle sit for 30-60 seconds before pouring. That usually gets you in the right range.

4. How long does coffee stay fresh after roasting?

For espresso, peak flavour is usually 2-10 days after roasting. For filter coffee, 7-21 days. After about 3-4 weeks, you'll notice the flavour fading — it won't taste bad, but it loses its vibrancy.

Look for a roast date on the bag. If there isn't one, that's usually a sign the roaster doesn't want you thinking too hard about freshness.

5. What's the difference between light, medium, and dark roast?

Light roast — Higher acidity, more of the original bean character comes through. You'll get floral, fruity, or tea-like notes. Slightly more caffeine (the roasting process burns off a tiny bit).

Medium roast — The sweet spot for a lot of people. Balanced acidity and body, caramel sweetness, versatile across brew methods.

Dark roast — Lower acidity, bolder body, more smoky and bitter notes. More oils visible on the surface of the bean. Less caffeine than lighter roasts, though the difference is small.

6. Does a finer grind make stronger coffee?

Not exactly. A finer grind increases the surface area, which means the water extracts more from the coffee — so it can taste more intense. But "stronger" in terms of caffeine? Not really. That's more about the coffee-to-water ratio and brew time.

What a finer grind does is change the extraction. Too fine for your brew method and you'll over-extract, ending up with something bitter. Too coarse and it'll be weak and sour. Match the grind to the method: fine for espresso, medium for filter, coarse for cafetiere.

7. What is cold brew and how is it different?

Cold brew is coffee steeped in cold or room-temperature water for 12-24 hours. No heat involved at all.

The result is typically smoother, naturally sweeter, and about 70% less acidic than hot-brewed coffee. It has a different flavour profile — less brightness, more chocolate and caramel notes. Caffeine content can actually be higher because of the long steep time and concentrate ratio.

It's a great way to drink decaf too. Swiss Water decaf cold brewed is incredibly smooth.

8. How does altitude affect coffee flavour?

Coffee grown above about 1,200 metres tends to develop more slowly, producing harder, denser beans with more complex sugars and acids. When roasted, these beans often have brighter acidity, more interesting flavours, and greater depth.

Lower-altitude coffee grows faster and tends to be softer, less acidic, and simpler in flavour. Neither is better or worse — it depends what you're after. But when you see "high altitude" on a bag, it's generally a quality signal.

9. What causes bitterness and how do I fix it?

Bitterness usually means over-extraction — you've pulled too much out of the coffee. Common culprits:

• Water too hot
• Grind too fine for the brew method
• Brewed too long
• Very dark roast

The fix is usually straightforward: try a coarser grind, slightly cooler water, or a shorter brew time. If you're consistently getting bitter coffee, it's almost always one of those four things.

10. How does the brew method affect taste?

Quite a lot, actually. Each method extracts differently:

Espresso — Concentrated, intense, full bodied. That thick crema on top is oils and gases that other methods filter out.

Pour-over — Clean and bright. Highlights acidity and subtle flavours because the paper filter removes oils and sediment.

French press (cafetiere) — Full bodied and rich, with more oils in the cup. You'll get sediment at the bottom — that's normal.

AeroPress — Smooth, low acidity, and surprisingly versatile. Great for experimenting.

Cold brew — Smooth, sweet, low acidity. A completely different drinking experience.

11. What is coffee bloom?

When you pour hot water over fresh coffee grounds, you'll see it bubble and expand. That's the bloom — carbon dioxide escaping from the beans.

It happens because CO2 builds up during roasting and slowly releases over time. Fresher coffee blooms more. If your grounds don't bloom much, they're probably a bit stale.

Most pour-over guides tell you to wet the grounds and wait 30-45 seconds before continuing. This lets the gas escape so the water can extract properly. Skip the bloom and the CO2 creates a barrier that leads to uneven extraction.

12. How much caffeine is in a cup of coffee?

A standard 240ml cup of brewed coffee has roughly 95-200mg of caffeine, depending on the bean variety, roast, and how you brew it. A single espresso shot has about 63mg in a much smaller volume.

Decaf? About 2-5mg per cup. A bar of dark chocolate has more.

13. What's the difference between single-origin and a blend?

Single-origin coffee comes from one place — a specific country, region, or even a single farm. The idea is to taste the characteristics of that particular origin: the soil, climate, altitude, and processing.

A blend mixes beans from different origins to create a specific flavour profile. Blends aim for balance and consistency — the same taste year-round, even as individual harvests vary.

Neither is inherently better. Single-origins are interesting; blends are reliable. We do both.

14. Does roast date matter?

Yes. Coffee is a fresh product, and roast date tells you where it is in its life.

Most coffee hits its sweet spot 3-14 days after roasting. Before that it can taste a bit gassy and underdeveloped. After 3-4 weeks, it starts losing the aromatics and vibrancy that make it interesting.

A bag with a "best before" date but no roast date could be months old. Look for roasters who put the actual roast date on the bag — it's a sign they care about freshness.

15. What's the right coffee-to-water ratio?

The standard starting point is 1:16 to 1:18 by weight — that's roughly 60g of coffee per litre of water. For stronger coffee, go closer to 1:15. For lighter, try 1:18 or 1:20.

If you don't have scales, a level tablespoon of ground coffee is about 7-8g. Two tablespoons per mug is a reasonable starting point, then adjust to taste.

The ratio matters more than people think. If your coffee tastes weak, adding more coffee usually fixes it better than brewing it longer (which just adds bitterness).

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