Health benefits of coffee report from Department of de Quimica.
During the roasting process, coffee bean components undergo structural changes leading to the formation of melanoidins, which are defined as high molecular weight nitrogenous and brown-colored compounds. As coffee brew is one of the main sources of melanoidins in the human diet, their health implications are of great interest. In fact, several biological activities, such as antioxidant, antimicrobial, anticariogenic, anti-inflammatory, antihypertensive, and antiglycative activities, have been attributed to coffee melanoidins. To understand the potential of coffee melanoidin health benefits, it is essential to know their chemical structures. The studies undertaken to date dealing with the structural characterization of coffee melanoidins have shown that polysaccharides, proteins, and chlorogenic acids are involved in coffee melanoidin formation. However, exact structures of coffee melanoidins and mechanisms involved in their formation are far to be elucidated.
Espresso is a much quicker and more aggressive affair unlike other methods such as immersion or pour over brewing which is giving the ground coffee flavors time to to evolve.
The high pressure steam and water rips the flavours and solids from the coffee making the flavour so intense. These beautiful insoluble oils and flavours extracted from the coffee produce the crème. This rich velvety cream is a product of CO2 in the beans, which escapes in the form of thousands of tiny bubbles under high pressure coated by melonoidins in the coffee. This robust crème should not be left to linger and many coffee connoisseur will suggest to drink it within 10 seconds before the crème starts to degrade. Hence creating the latte, giving you just 10 seconds to add the milk – such is the precious value of the crème. The crème enriches the texture and flavour of the drink and more importantly points to the freshness of the beans. So beans roasted from a long time ago (3 weeks max) will be less gassy and produce less crème revealing the use of stale beans. The beans roasted can also produce different amounts of crème i.e. Robusta beans often used in vacuum packed blends as they produce more crème than Arabica beans. It is worth noting that crème is not in itself a mark of excellent flavour. Unfortunately, terrible coffee produces crème just as reliably as excellent coffee. Look at the way the crème settles as the shot is poured. The whole shot will appear to be crème as it brews, before settling into distinct sections after pouring. Fresh Coffee!