• Serena Written by Serena Lorenzi, Communication manager | September 18, 2023

Interview with Nicola Grande, master brewer about the craft beer production process

Nicola Grande, head brewer


Craft beer has an ever-increasing importance in the current market and the type of product offered can determine the market response. Microwave extractors for the food sector can bring great innovation to the beer production sector.
We interviewed Dr. Nicola Grande, a master brewer, about this topic.
We will talk about his experince with microwave hop extraction and his contribution to help Milestone in developing True Hopping technology.


MILESTONE: Could you tell us about your experience in the world of craft beer?
Dr. Grande (master brewer): I have been working in this professional field for several years, but even before embarking on it as a career I was passionate about it. I made my first beer in 1996 when I was still at university and I didn't think it would become my profession. Since then, research and study have always been growing and I have always dedicated myself to this topic.
It should also be added that in the mid-90s there were no specific courses for the art of brewing in Italy: the first craft breweries were starting to emerge, and the products that were being produced were the result of the specific skills of the first master brewers. The agricultural studies at the foundation were not dedicated to beer, so the product was heavily influenced by individual interests and the application that could be made of those studies. Initially, everyone brought their own expertise to beer, which often stemmed from a passion before being a well-defined study.
Q2: What is the classic beer fermentation process?
The role of the Master Brewer is to prepare a wort from grains, whether malted or not. Malt is not a cereal itself; rather, it's the product of an enzymatic process that starts with barley to produce this sugary liquid based on water. Before being taken to the fermentation stage with yeast, the produced wort is flavored with hops, which serves to balance the sweetness with a bitter note. The percentages of hops used depend greatly on the type of beer one wants to produce.
Q3: In which phase of this process do microwaves intervene?
Microwaves intervene in the hop addition phase of the brewing process. This phase serves two purposes: imparting bitterness to the beer and giving the product a specific aroma. Over the years, it has been discovered that hops not only have bittering properties but also aromatic ones. Microwaves initially affect the aromatic aspect of the hops, but we have managed to optimize the process by using the same amount of hops for both the production of aromatic oil and the bittering component. This was a step beyond the initial expectations, allowing for process optimization with a dual function in extracting essential oil and using the residual solid part to give bitterness to the product.
Q4: How do microwaves impact the process?
In the hop addition process, brewers typically prefer not to use hop flowers but rather the pressed product formulated into pellets. These pellets are added during the boiling process for the reasons already described. In the case of microwave usage, the hop-related process occurs externally as a parallel process, not inside the main brew kettle. The products obtained are then inserted subsequently, because some of the reactions that take place during boiling with the traditional method occur in the microwave reactor.
In the traditional process, hops must be added before boiling because the isomerization of α-acids only occurs at high temperatures. In the case of microwaves, this reaction takes place during the extraction process. The equipment includes a glass reactor where hops are added with water, and then the microwave extraction process is initiated at a specific temperature for a predetermined time, allowing the formation of aromatic essential oil and the bittering fraction.
Given the conditions under which the extraction process takes place, the isomerization reaction has already occurred, so it is not necessary to add hops during the boiling phase. This applies to the bittering component, while the essential oil is added at the end of fermentation to preserve volatile substances.
Q5: Have you personally used the ETHOS X system in brewing?
Yes, I developed the method together with Milestone trying to optimize the process in the best possible way.
Q6: What are the things that struck you the most?
First of all, in economic terms, less hops are needed to achieve the same product that I have always produced. But an even more interesting aspect is undoubtedly the ability to expand the available aromatic spectrum. The quality and potential of the aromatic oil produced are crucial factors to consider.
The aromatic potency of the terpene oil is very high and allows for aromas and fragrances that would otherwise not be achievable. This enables the creation of much more varied products with innovative organoleptic characteristics. Another very interesting aspect is the quality and duration of the entire process. Working with pellets makes the beer maturation reaction messier and involves product settling times in the fermenter. When using aromatic oil, the process is cleaner, and the reaction times in the fermenter are shorter, allowing for increased production.
Q7: What aspects do you consider to be the most innovative and interesting in the use of microwaves?
What was just mentioned is certainly one of the most interesting and innovative aspects, but there is also a second aspect that is equally important: the management of essential oil, which is much simpler compared to hops. The latter, in fact, tends to oxidize, making the product less pleasant, so it requires good organization in storage to avoid wasting unusable product. Managing essential oil is much simpler in storage. Not to mention the space factor, where kilograms of hops are equivalent to a few hundred milliliters of oil. I would say that it is a lean and cost-effective method of management.
Q8: Do you think using this technology is “the future”?
Yes, I really think this technology is very important. There's a clarification to be made: essential oils extracted from hops are already available in the market, but they are standard and not customizable products. The possibility of working with the product internally opens up new perspectives, allowing for the customization of aroma that was never previously possible. This, of course, is a very interesting aspect that could bring many innovations to the industry.
Q8: What technical characteristics do you find "indispensable" for craft beer production?
The possibility to have the essential oil produced internally
Q9: Use three adjectives to describe this technique and the ETHOS X system
Innovative and above all customizable, due to the fact that the essential oils available on the market are standard products that cannot be tailor-made.

True Hopping Extraction for Breweries

To improve the hop flavor extraction efficiency of the conventional dry-hopping process Milestone has applied a novel hopping technique called True Hopping, which uses the well-established solvent-free microwave extraction (SFME) approach.
True Hopping Extraction for Breweries


Watch the workflow of the process
The ETHOS X 2.0 and ETHOS XL easily integrates to your brewery process regardless of the hops variety chosen. To obtain the pure extracts from hops variant, you only need to load the material into the system and press start. The extract can be stored in glass at -18°C to ensure flavor stability for several months. When needed, the distilled hop oil is mixed with a carrying agent and added into fermenter and/or in whirpooling/ sedimentation tank for hopping, while extracted hops matter can be added in kettle for bittering in the last 10 minutes of the boil.
We call this approach True Hopping, as it maximises hops utilisation, thereby significantly reducing the amount of hops pellets used to achieve the same beer flavor profile. True Hopping then considerably increases the production yields which effectively reduces the beer production costs.