Besides roasting coffee in the right way for most effective sampling and cup tasting, the correct coffee ground size goes hand in hand and thus plays an important role so often missed by coffee lab operations.
Not only should the grounds be consistent in particle size, but also should the overall size correspond to the brewing method, which between cup tasters simply means adding boiled water to the powder and giving it a good stir then finally letting the particles settle to the ground of the cup.

The ideal ground size for all fragrances and aromas to be most potent is between regular Drip Coffee and French Press, slightly more towards the larger French Press size. For beginners to verify this ideal particle size it may be best to purchase a pack of coffee from a renowned manufacturer, or to take a walk to a popular coffee shop down the road that sells whole bean coffee and has a grinder and well-trained staff. More advanced labs, especially those business involved in the instant coffee industry, may carry wire mesh sieves shakers that are a handy tool when evaluating the right ground size for cupping and also adjusting the output of the grinder in use.

In any case, try to always stick to the same ground size when cupping your coffees. Consistency in everything that you do in the lab is key. Having a proper grinder in your lab is certainly a good investment. Burr grinders are the preferred choice over blade grinders as they improve both the quality and ease of brewing. For any more advanced or scientific analysis, blade grinders are unacceptable due to their lack of reproducibility.