Tanzanian Coffee Analysis: PB Northern Selian Estate

This Tanzanian coffee comes from the Selian Estate, which is part of the Burka Estates – made up of Burka, Selian and Mondul. The Burka estates are one of the largest in the Arusha Region.

This coffee consists of ‘Peaberries’ as opposed to ‘Flat Berries.’ Specifically, a peaberry is a small round coffee bean. Only about 5% of coffee cherries have the abnormality that causes a peaberry to form instead of two flat berries. A peaberry most often occurs when for some reason only one ‘seed’ within the coffee fruit is fertilized, which means that as the fruit develops it will create only one coffee ‘bean’ as opposed to two. Rumor has it that they have more ‘flavor’ within them because all of the nutrients end up in one bean as opposed to two. There is unfortunately very little data to refute or support this idea.

On the cupping table, peaberries can taste quite similar to ‘flat beans.’ They are subject to all of the normal standards needed to produce a high quality specialty coffee. They have to be sorted out post-harvest and -processing. Often this sorting happens by hand, which is quite labor intensive. If they were just left in with the other beans, it would be quite challenging for roasters being that a peaberry is quite a different shape than a ‘regular’ coffee bean. One of the theories in regards to quality with peaberries is that the very uniform and even shape makes for more consistent roasting and therefore a higher quality brew.

Tanzanian Coffee Roast Analysis

Peaberries are smaller and denser than their flattened cousins. Higher density coffees will generally have a higher acidity, so we will roast it faster and lighter to try to highlight this acidity. Achieving a faster roast in a high density coffee is possible because of the efficient heat transfer throughout the bean. We can use higher temperatures in the initial roast phases without fear of the beans scorching, since the heat will transfer inward. To keep our rate of rise declining, and ensure a light roast, we will decrease our heat rapidly as we approach first crack. Like the Tanzania AA, the moisture content was middle of the road at 10.7%

Stronghold S7

We tried out 3 different roast approaches on the Stronghold S7:

Roast 1: Medium charge temperature with a total roast time of 9:41 with 23% development and a medium-high end temperature. We held off on lowering the heat application until late yellowing. This roast had aromatics of peach, apple, black tea, pear and bread with flavors of caramel, chocolate, orange, and a slight smokiness and dark brown sugar on finish. The body was thick with very light acidity.

Roast 2: Same charge temperature as Roast 1 with a slightly shorter time of 9:00 and less development – 20% and the same end temperature. We were hoping to capture more of that acidity with the shorter roast time. This roast had aromatics of chocolate, apple, slight honey, florals, and cherry with flavors of cola, nougat, apples and pears, sweet throughout with lingering caramel notes. The body was syrupy and cashew milk-like. The acidity malic and a touch more prominent.

Roast 3: We used a slightly lower charge temperature and a slightly longer roast of 10:15, with 19% development and a slightly lower end temperature. The aroma was full of juicy fruits, cherry, caramel, raspberry and coffee blossom. The flavor, black tea, lemon, raspberry with a nougat finish and a crisp acidity coupled with a round body. This roast was most definitely the winner.

Hario V-60

We chose to brew it on a Hario V-60 with a Baratza Virtuoso Grinder. V-60’s with their cone shape, fast flow rate, and open bottom, do a wonderful job of highlighting the complexity and acidity in a coffee. They also allow for maximum flexibility when dialing in a coffee.

We started with a 1:17 ratio to capture the floral and black tea flavor aspects of this coffee. The starting recipe was 22g of coffee ground on ’18’ with 375ml of filtered water, delivered in 4 slow pours, with total drip out time being 4:25. This had a very intense coffee blossom aroma coupled with baked pear. The beverage though was full of cacao, slight red fruit, cola with a bitter finish. The Total Dissolved Solids for the brew was 1.75% and the beverage was clearly over-extracted and too strong overall.

We adjusted the grind coarser to tame the strength and extraction while keeping the amount of coffee and water used consistent.

Our final recipe was as follows:

·22g of coffee (6 days off roast) ground at 24 on a Baratza Virtuoso Grinder with 205F filtered water

·25 second bloom with 45ml of water

·6 – 55ml pours with the final pour ending at 2:45 seconds and the final drip time being 3:00 seconds. This resulted in a 335ml beverage.

Final thoughts on this Tanzanian coffee:

The final cup had aromatics of baking cookies and honey and was full of peaches, honey, florals, with touches of lemon zest throughout. The body was round and the coffee was overall very sweet with a delicate acidity.

The coffee is currently available for purchase here.