Italians love coffee. Drinking coffee is a kind of ritual for us: hurried or unhurried, there’s always time for a coffee break! Since coffee-drinking is so important to us, understanding how to make a perfect espresso and how to monitor the production process are also fundamental issues for us.
At Alfatestlab, we offer essential characterization services to support coffee manufacturers, helping them to monitor and improve their production process, for a perfectly-brewed coffee.
Particle size analysis of coffee powder
When it comes to making the perfect coffee, the grind plays a key role. The consistency of the ground material can affect the flavour and brewing time of the coffee, as well as the possible brewing methods. If, for instance, you are preparing an espresso or Turkish coffee, a very fine grind with grain sizes below 1 mm is required, whereas, for common drip-brewed and filtered coffee, particle size is below 1.5 mm and, for Scandinavian, French press or American brewed coffee, it is just below 3 mm.
If you are a coffee pod producer, you will be interested in the ratio between fine and coarse particles in your ground formulations as it impacts on the time and pressure required for brewing.
Through laser diffraction techniques (Mastersizer 3000 – Malvern Panalytical), Alfatestlab can provide particle size distribution (PSD) results you can depend on, with rapid and reliable measurements.
Shape analysis of coffee powders
Particles shape, too, certainly plays a key role in powder processability. When particle size distribution alone does not explain why batches do not behave in the same way, morphological analysis offers a deeper insight into your samples by characterising the size and shape distributions of the powder, particle by particle. At Alfatestlab, we perform morphological analysis using an optic granulometer (Morphologi 4-ID – Malvern panalytical), providing the number- and volume-based particle size as well as statistical morphological parameter distributions such as circularity, elongation, aspect ratio, etc.
Sensory analysis of coffee
You don’t just taste your coffee: you smell it, too. In fact, if you ask people on the street, they’ll tell you that the best thing about their morning brew is its delicious aroma. Our noses have such accurate receptors for the molecules that make up aromas that we can easily distinguish between aroma molecules differing by just one carbon atom. It is this sensitivity that enables us to differentiate between variations on an aromatic theme.Understanding the role of volatile substances in your brewed coffee gives you a molecular-scale boost in differentiating between different coffee qualities, monitoring your raw materials and tracing their origins.At Alfatestlab, we use an electronic nose (Heracles II – Alphamos), based on flash gas chromatography technology, to assess the chemical composition and related sensory attributes of powders and liquids. This instrument enables us to evaluate the smell fingerprints of your sample by identifying the chemical compounds that make up the smell through qualitative and quantitative analysis together with an automated data processing software with multivariate statistics.
Coffee creaming analysis
Crema is a flavorful, aromatic, reddish-brown froth that rests on top of a shot of espresso. It is formed when air bubbles combine with a fine-ground coffee’s soluble oils. The strong presence of crema in an espresso shot indicates a high-quality, well-ground coffee and a skilled barista or good espresso-machine. Crema helps give espresso a fuller flavor and longer aftertaste than drip coffee. Wheter you’re a coffee machine producer or a ground coffee supplier, you may be interested in comparing different brewed coffees based on their crema thickness and its stability over time.
At Alfatestlab, we perform this test using a stability analyzer that permits fast and sensitive identification of destabilization mechanisms, such as foam collapse (as well as creaming, sedimentation, flocculation, coalescence, etc.). Six independent measurement items permit simultaneous comparison of up to six formulations at a time, with integrated temperature control.
Porosity and Specific Surface Area Analysis of coffee powder
There are a few variables that can be used when manipulating extraction. The two main contenders are time and surface area. These two variables are closely intertwined in every single type of brewing environment, meaning that you can’t change one without changing the other. Increasing the surface area of the coffee makes it far easier for the water to dissolve the flavours and, when you grind coffee, you increase the surface area exponentially.
At Alfatestlab, we offer Specific Surface Area (SSA) and porosimetry analysis using gas physisorption instruments (Tristar II, 3-Flex – Micromeritics) that provides high-quality data with fully automated measurements.
Coffee powder flow analysis
Dealing with powders can be challenging at times, since their behaviour is influenced both by particles’ physical properties (size, shape, density, cohesion, surface texture and area, etc.) and by environmental factors (consolidation, aeration, equipment surface material, humidity, etc.). Powder properties, indeed, influence the way the materials behave in the processing environment and the characteristics of the final product.
At Alfatestlab, we use a powder rheometer (FT4 – Freeman Technologies – micromeritics) to measure powders’ flow dynamics, bulk properties and behaviour and a helium pycnometer (Accupyc – Micromeritics) to measure the apparent density of the particles in a powder.
Analysis of coffee particle characteristics, coffee creaming and bulk powder flow properties together with sensory analysis and high resolution SEM images can help you improve your coffee production process. Contact us to discuss how Alfatestlab can support you!
