How Do Hops Affect The Flavor Of Beer?

Hops, the flowers of the Humulus lupulus plant, are one of the four essential ingredients in beer, alongside water, malt, and yeast. They play a crucial role in defining the flavor, aroma, and overall character of the beer. While malt provides the sweetness and yeast is responsible for fermentation, hops add the necessary bitterness to balance the sweetness, prevent spoilage, and contribute unique flavors and aromas. The versatility of hops allows brewers to craft a diverse range of beer styles, from intensely bitter IPAs to subtly nuanced lagers.
Understanding how hops affect the flavor of beer involves delving into their history, chemistry, and the various techniques used in brewing. This exploration reveals the complexity and artistry behind brewing, showcasing how different hop varieties and their utilization at different stages of brewing can create a myriad of flavors and aromas, making each beer unique.

The Chemistry of Hops

Hops are rich in a variety of chemical compounds that significantly influence the flavor, aroma, and stability of beer. Understanding these compounds—alpha acids, beta acids, essential oils, and polyphenols—provides insight into how hops impact the brewing process and the final product’s sensory characteristics.

Alpha Acids

Alpha acids are the primary contributors to the bitterness in beer. They are present in the resin glands of hop cones and include humulone, cohumulone, and adhumulone. During the boiling process in brewing, alpha acids undergo isomerization, transforming into iso-alpha acids. This chemical change increases their solubility in the wort, the liquid extracted from the mashing process, imparting a bitter taste that balances the sweetness of malt.

Humulone: The most prevalent alpha acid, contributing a clean bitterness.
Cohumulone: Known for its sharp bitterness, it is often less desired in large quantities.
Adhumulone: Contributes a milder bitterness compared to humulone and cohumulone.

The level of bitterness imparted by alpha acids is measured in International Bitterness Units (IBUs), allowing brewers to control and standardize the bitterness of their beer.

Beta Acids

Beta acids, comprising lupulone, colupulone, and adlupulone, are less influential on the immediate flavor profile of beer compared to alpha acids. They do not undergo isomerization during boiling, making them less soluble. However, beta acids oxidize over time, producing compounds that can contribute to the overall bitterness and stability of the beer as it ages.

Lupulone: The most common beta acid, contributing to the preservation qualities of hops.
Colupulone: Similar in structure to lupulone but less prevalent.
Adlupulone: Present in smaller quantities and contributing to the long-term flavor stability.

Beta acids play a crucial role in the aging process of beer, affecting the flavor profile as the beer matures.

Essential Oils

Essential oils in hops are volatile compounds that provide distinctive aromas and flavors, contributing significantly to the sensory experience of beer. The main essential oils found in hops include myrcene, humulene, caryophyllene, and farnesene. Each of these oils has a unique aromatic profile:

Myrcene: Responsible for citrusy, floral, and herbal notes, myrcene is the most volatile and degrades quickly during boiling.
Humulene: Contributes woody, earthy, and spicy aromas, providing a complex and rounded character.
Caryophyllene: Adds spicy, peppery, and herbal flavors, enhancing the beer’s depth.
Farnesene: Offers floral, fruity, and green apple notes, often found in noble hop varieties.

The timing of hop addition during brewing—whether during the boil, whirlpool, or as a dry hop—affects the retention and expression of these essential oils, thereby influencing the final aroma and flavor profile of the beer.

Polyphenols

Polyphenols are complex organic compounds found in hops that contribute to the mouthfeel, astringency, and stability of beer. They include tannins, which are responsible for the astringent or puckering sensation in the mouth. Polyphenols interact with proteins in the beer, influencing its clarity and stability.

Tannins: Contribute to astringency and help with the protein-polyphenol haze formation, which can affect the clarity of the beer.
Flavonoids: Antioxidant properties that help in preserving the beer’s flavor and preventing oxidation.

Polyphenols also have antioxidant properties, which can help protect beer from oxidation and extend its shelf life. They play a role in the overall sensory profile, contributing to the perceived body and complexity of the beer.

Understanding the chemistry of hops can help us understand how it affects the taste of beer. Alpha acids provide bitterness, balancing the malt’s sweetness; beta acids contribute to long-term flavor stability; essential oils deliver distinctive aromas and flavors; and polyphenols influence mouthfeel, clarity, and antioxidant properties. By mastering the interplay of these compounds, brewers can craft beers with diverse and complex flavor profiles, catering to a wide range of palates and preferences.

Varieties of Hops

Hops not only impart bitterness and preservative properties to beer, but they also give it a unique flavor and aroma. The diversity of hop varieties allows brewers to create a wide array of beer styles, each with its distinct character. Hops are typically categorized into three main types based on their primary use in brewing: bittering hops, aroma hops, and dual-purpose hops. Each category has specific characteristics and applications, making them suitable for different stages of the brewing process.

Bittering Hops

Bittering hops, also known as high-alpha hops, are primarily used to impart bitterness to the beer. They have high levels of alpha acids, which are responsible for the bitter taste. These hops are added early in the boiling process to maximize the isomerization of alpha acids into iso-alpha acids, which dissolve in the wort and provide the necessary bitterness to balance the sweetness of the malt.

Magnum: Known for its clean bitterness and high alpha acid content, Magnum is a versatile hop used in a variety of beer styles.
Columbus: Often used for its strong, clean bitterness, Columbus also adds a slightly earthy and spicy character.
Northern Brewer: Provides a balanced bitterness with subtle minty and evergreen notes, making it suitable for many traditional beer styles.

The bitterness these hops provide can create a balanced and drinkable beer, especially in styles that emphasize bitterness, such as India Pale Ale (IPA) and American Pale Ale (APA).

Aroma Hops

Aroma hops are prized for their aromatic properties rather than their bittering potential. These hops have lower alpha acid levels and higher concentrations of essential oils, which contribute to the beer’s aroma and flavor. Aroma hops are typically added later in the brewing process, such as during the late boil, whirlpool, or dry hopping stages, to preserve their volatile oils.

Cascade: One of the most popular aroma hops, Cascade imparts floral, citrus, and grapefruit notes. It’s a staple in many American-style ales.
Saaz: A traditional noble hop used in lagers and pilsners, Saaz provides a delicate floral and herbal aroma with a mild bitterness.
Hallertau: Another noble hop, Hallertau offers mild, earthy, and slightly spicy aromas, commonly used in traditional German lagers.

Aroma hops play a crucial role in defining the sensory experience of a beer, contributing to its bouquet and flavor profile. They are essential in styles where hop aroma is a key feature, such as IPAs, saisons, and certain Belgian ales.

Dual-Purpose Hops

Dual-purpose hops are versatile varieties that can be used for both bittering and aroma. They offer a balanced profile of alpha acids and essential oils, making them suitable for various stages of the brewing process. These hops provide brewers with the flexibility to achieve both desired bitterness and complex aromatic profiles from a single hop variety.

Centennial: Known as a “super Cascade,” Centennial offers both strong bitterness and a floral, citrusy aroma, making it a popular choice for American ales.
Simcoe: Valued for its versatility, Simcoe provides a balanced bitterness and a unique combination of earthy, pine, and fruity aromas.
Amarillo: With moderate alpha acid levels and rich essential oils, Amarillo imparts a complex mix of floral, citrus, and tropical fruit notes.

Dual-purpose hops are particularly useful in crafting beers with layered hop profiles, where both bitterness and aroma are desired. They are commonly used in styles like American Pale Ales, IPAs, and stouts, allowing brewers to achieve a harmonious balance of flavors and aromas.

The variety of hops available to brewers offers a vast palette of flavors and aromas to experiment with. Bittering hops provide the necessary backbone of bitterness, aroma hops enhance the beer’s sensory appeal, and dual-purpose hops offer flexibility and complexity. By understanding and utilizing these different hop varieties, brewers can create a wide range of beer styles, each with its unique character and appeal. The careful selection and combination of hops allow for endless creativity in brewing, contributing to the diversity and richness of the beer landscape.

Hop Flavors and Aromas

Hops are renowned for their ability to impart a wide range of flavors and aromas to beer, significantly influencing its overall character. The specific flavors and aromas that hops contribute are largely determined by the hop variety and the essential oils present in the hop cones. Here, we explore the primary flavor and aroma profiles that hops can bring to beer, including citrus, piney/resinous, floral, herbal, spicy, and fruity notes.

Citrus

Citrus is one of the most common and sought-after hop aromas, especially in modern craft brewing. Hops that impart citrus flavors and aromas are typically rich in essential oils like myrcene, limonene, and citral. These oils produce notes reminiscent of lemon, orange, grapefruit, and other citrus fruits, adding a bright and refreshing quality to the beer.

Examples: Citra, Cascade, Amarillo
Beer Styles: IPAs, American Pale Ales, Wheat Beers

Citrus-flavored hops are often used in hop-forward styles, providing a zesty and invigorating aroma that enhances the beer’s freshness and drinkability. These hops are particularly popular in American-style ales, where bold citrus notes are a defining characteristic.

Piney/Resinous

Piney and resinous hops are known for their earthy and forest-like aromas, reminiscent of pine trees and resin. These flavors and aromas are primarily due to the presence of essential oils such as pinene and myrcene. Piney hops add a grounding and sometimes sharp characteristic to the beer, balancing sweeter malt profiles with their resinous bitterness.

Examples: Simcoe, Chinook, Columbus
Beer Styles: IPAs, Double IPAs, American Strong Ales

The piney and resinous qualities of these hops are often used to create complex and robust flavor profiles, making them a staple in many West Coast IPAs and other hop-centric beers. They contribute to a more intense and layered hop character.

Floral

Floral hops provide delicate and perfumed aromas that can range from fresh flowers to fragrant blossoms. These hops contain essential oils like geraniol and linalool, which contribute to their floral character. Floral hops are appreciated for their subtle and nuanced aroma, adding elegance and sophistication to the beer.

Examples: Hallertau, Saaz, East Kent Goldings
Beer Styles: Pilsners, Lagers, Belgian Ales

Floral hops are often used in traditional European beer styles, where a refined and balanced hop presence is desired. They enhance the beer’s aroma without overpowering the malt and yeast characteristics, providing a harmonious and integrated flavor profile.

Herbal

Herbal hops offer flavors and aromas reminiscent of fresh herbs, such as mint, basil, and thyme. These hops typically contain essential oils like humulene and caryophyllene, which impart earthy and green notes. Herbal hops add a fresh and sometimes slightly bitter quality to the beer, reminiscent of a herb garden.

Examples: Fuggle, Tettnang, Styrian Goldings
Beer Styles: English Bitters, Pilsners, Saisons

Herbal hops are often used in traditional and farmhouse styles, where their earthy and fresh characteristics complement the malt and yeast profiles. They provide a natural and grounded flavor that enhances the beer’s complexity.

Spicy

Spicy hops contribute peppery, clove-like, or even cinnamon-like aromas and flavors to beer. These characteristics are due to the presence of essential oils such as caryophyllene and farnesene. Spicy hops add a distinct and sometimes sharp quality to the beer, enhancing its complexity and depth.

Examples: Saaz, Perle, Spalt
Beer Styles: Belgian Ales, German Lagers, Saisons

Spicy hops are commonly used in traditional European styles, where their distinctive spiciness adds a unique and memorable aspect to the beer. They are especially prevalent in Belgian and German beers, contributing to the signature flavors of these styles.

Fruity

Fruity hops offer a broad range of fruit-like aromas and flavors, from tropical fruits like mango and pineapple to stone fruits like peach and apricot. These hops contain high levels of essential oils such as myrcene and geraniol, which provide their fruity character. Fruity hops are highly prized for their ability to create vibrant and juicy flavor profiles.

Examples: Mosaic, Galaxy, Azacca
Beer Styles: New England IPAs, Pale Ales, Fruit Beers

Fruity hops are a cornerstone of modern hop-forward styles, especially the hazy and juicy New England IPAs. They contribute to the beer’s tropical and juicy character, making it taste almost like a fruit smoothie. These hops are used to create beers with a lush and aromatic profile, appealing to those who enjoy bold and expressive flavors.

The diverse range of hop flavors and aromas allows brewers to craft beers with unique and complex sensory profiles. Whether it’s the bright citrus of Citra, the earthy pine of Simcoe, the delicate floral notes of Hallertau, the fresh herbal character of Fuggle, the spicy kick of Saaz, or the juicy fruitiness of Mosaic, each hop variety brings something special to the beer. By understanding and skillfully utilizing these hop characteristics, brewers can create a vast array of beer styles, each with its distinct flavor and aroma, catering to a wide range of tastes and preferences.

Brewing Techniques and Hop Usage

The impact of hops on beer flavor is not only determined by the hop variety but also by how and when the hops are added during the brewing process. Different techniques and timings of hop additions can extract various flavors, aromas, and bitterness levels from the hops, allowing brewers to create a wide range of beer styles. Here, we explore four primary methods of hop usage: bittering addition, flavor addition, aroma addition, and dry hopping.

Bittering Addition

Bittering hops are added at the beginning of the boiling process, typically with a boil time of 60 minutes or more. This extended boil time allows for maximum isomerization of alpha acids into iso-alpha acids, which dissolve in the wort and provide the essential bitterness needed to balance the sweetness of the malt.

Purpose: To impart bitterness, which balances the malt’s sweetness and provides a backbone to the beer’s flavor.
Hops Used: High alpha acid hops, such as Magnum, Columbus, and Northern Brewer.
Effect on Flavor: The long boiling time diminishes the delicate aromas and flavors of the hops, leaving primarily the bitter compounds. This addition does not significantly impact the beer’s aroma but provides the necessary bitterness.

Bittering addition is crucial for creating balanced beers, particularly in styles that emphasize bitterness, such as IPAs and pale ales.

Flavor Addition

Flavor hops are added later in the boil, typically around 15 to 30 minutes before the end of the boiling process. This timing allows for some of the essential oils to remain in the wort, contributing to the beer’s flavor without overpowering bitterness.

Purpose: To add hop flavors to the beer, creating a more complex and layered taste profile.
Hops Used: Varieties with good flavor characteristics, such as Cascade, Centennial, and Simcoe.
Effect on Flavor: This addition imparts a balance of bitterness and hop flavor, with some essential oils surviving the boil to contribute notes of citrus, pine, floral, or herbal characteristics depending on the hop variety.

Adding flavors can enhance the flavor complexity of a beer, making it more interesting and enjoyable.

Aroma Addition

Aroma hops are added at the end of the boil or during the whirlpool stage, typically with a boil time of 5 to 15 minutes. The shorter exposure to heat helps preserve the volatile essential oils, which are responsible for the hop’s aromatic properties.

Purpose: To enhance the beer’s aroma without adding significant bitterness.
Hops Used: Varieties known for their aromatic qualities, such as Amarillo, Saaz, and Hallertau.
Effect on Flavor: This technique maximizes the retention of essential oils, leading to a pronounced hop aroma that can include notes of flowers, fruit, spices, or herbs. The late addition minimizes bitterness, focusing on aroma.

Aroma addition is particularly important in styles where hop aroma is a defining feature, such as pale ales, IPAs, and certain lagers.

Dry Hopping

Dry hopping involves adding hops during or after fermentation, without subjecting them to boiling. This method maximizes the extraction of essential oils, providing a strong hop aroma without contributing to the beer’s bitterness.

Purpose: To impart intense hop aroma and fresh hop flavors.
Hops Used: Aromatic varieties, such as Citra, Mosaic, and Galaxy.
Effect on Flavor: Dry hopping significantly enhances the beer’s aroma, offering a burst of fresh hop character that can include tropical fruits, citrus, pine, or floral notes. Since the hops are not boiled, there is minimal addition of bitterness, making this technique ideal for aromatic emphasis.

Dry hopping is widely used in hop-forward styles like IPAs, pale ales, and New England IPAs, where a vibrant hop aroma is desired.

The timing and method of hop addition during brewing play a critical role in shaping the flavor and aroma profile of beer. Bittering addition provides the essential bitterness that balances the malt’s sweetness, while flavor addition introduces complex hop flavors. Aroma addition enhances the beer’s aromatic qualities, and dry hopping imparts intense, fresh hop aromas without adding bitterness. By understanding and mastering these techniques, brewers can manipulate hop characteristics to create a diverse array of beer styles, each with its unique flavor and aromatic profile.

Techniques for Maximizing Hop Flavor

In the quest to enhance and maximize hop flavor and aroma in beer, brewers have developed several innovative techniques. These methods focus on preserving the delicate essential oils and compounds that contribute to the hop’s unique characteristics. Here, we explore four advanced techniques: hopback, whirlpool hopping, cryo hops, and double dry hopping.

Hopback

A hopback is a vessel filled with fresh hops through which hot wort is passed before it goes into the fermentation tank. This technique allows for maximum extraction of hop oils while minimizing the loss of volatile aromatic compounds.

Purpose: To intensify hop aroma and flavor by infusing the wort with fresh hop oils.
Process: After boiling, the hot wort is passed through a hopback filled with whole cone hops or hop pellets. The hot wort extracts essential oils from the hops, which are then carried into the fermentation tank.
Effect on Flavor: The hopback process captures a broad spectrum of hop aromas and flavors, adding depth and complexity to the beer. It enhances the fresh, green hop character without contributing additional bitterness.

The hopback is particularly effective for creating beers with a strong, fresh hop aroma and is often used in conjunction with other hop addition techniques.

Whirlpool Hopping

Whirlpool hopping involves adding hops to the wort during the whirlpool stage, which occurs after the boil and before cooling. This technique is designed to maximize the retention of hop oils while minimizing the extraction of bitterness.

Purpose: To enhance hop aroma and flavor without adding significant bitterness.
Process: After the boil, the wort is circulated in a whirlpool, creating a vortex. Hops are added during this stage, and the wort is left to settle for 20-40 minutes. The lower temperature of the whirlpool (compared to the boil) helps preserve the volatile essential oils.
Effect on Flavor: Whirlpool hopping provides a robust hop aroma and flavor with minimal bitterness. It allows for the extraction of delicate floral, fruity, and herbal notes, contributing to a well-rounded hop character.

Whirlpool hopping is widely used in hop-forward styles like IPAs and pale ales, where a prominent hop aroma is desired.

Cryo Hops

Cryo hops are a concentrated form of hops created by separating the lupulin (the resin and aromatic compounds) from the hop plant matter at extremely low temperatures. This results in a product with intense hop flavor and aroma while reducing the amount of vegetal matter.

Purpose: To intensify hop flavor and aroma while reducing the amount of plant material needed.
Process: Cryo hops are added at various stages of brewing, similar to traditional hops, but in smaller quantities due to their concentrated nature.
Effect on Flavor: Cryo hops provide a powerful burst of hop aroma and flavor, including intense citrus, pine, and fruity notes. The reduced vegetal matter also means less astringency and a cleaner hop profile.

Cryo hops are particularly effective for dry hopping and late additions, where maximizing aroma and flavor is crucial.

Double Dry Hopping

Double dry hopping involves adding hops to the beer at two different points during or after fermentation. This technique aims to maximize hop aroma and flavor by layering hop additions.

Purpose: To create a more complex and intense hop aroma and flavor profile.
Process: The first dry hop addition typically occurs towards the end of primary fermentation, while the second addition happens after primary fermentation is complete. This staggered approach allows for different hop compounds to be extracted and retained at each stage.
Effect on Flavor: Double dry hopping results in a beer with a rich, multi-dimensional hop character. The initial dry hop addition infuses the beer with fresh hop oils, while the second addition reinforces and enhances the hop aroma and flavor, creating a layered and dynamic profile.

Double dry hopping is a popular technique in the production of hazy IPAs and other aromatic beer styles, providing a vibrant and fresh hop experience.

The techniques for maximizing hop flavor—hopback, whirlpool hopping, cryo hops, and double dry hopping—demonstrate the innovative approaches brewers use to enhance the sensory qualities of beer. Each method offers unique advantages, from capturing fresh hop aromas to intensifying flavors with concentrated hop products. By mastering these techniques, brewers can create beers with exceptional hop character, offering drinkers a rich and aromatic experience that showcases the full potential of hops. These advanced methods contribute to the diversity and complexity of the beer landscape, allowing for endless creativity and innovation in brewing.

The Role of Hops in Different Beer Styles

Hops play a pivotal role in defining the flavor profiles of various beer styles. By selecting specific hop varieties and employing unique brewing techniques, brewers can create a wide range of flavors and aromas that cater to different preferences.

Pale Ales and IPAs

Pale Ales and India Pale Ales (IPAs) are among the most hop-forward beer styles, showcasing the diverse flavors and aromas that hops can impart. These styles are characterized by their pronounced hop bitterness, vibrant aromatics, and complex flavor profiles.

Hop Characteristics: Citrus, pine, floral, herbal, spicy, and fruity notes.
Popular Hop Varieties: Cascade, Centennial, Citra, Simcoe, Amarillo, Mosaic.
Brewing Techniques: Bittering additions early in the boil provide the necessary bitterness, while late additions and dry hopping enhance the aromatic qualities. Techniques like whirlpool hopping and double dry hopping are commonly used to intensify hop flavors and aromas.

Lagers and Pilsners

Lagers and Pilsners typically showcase a more subtle hop character compared to Pale Ales and IPAs, emphasizing balance and drinkability. The hop presence in these styles adds crispness and a refined bitterness that complements the clean malt profile.

Hop Characteristics: Floral, herbal, spicy, and earthy notes.
Popular Hop Varieties: Saaz, Hallertau, Tettnang, Perle.
Brewing Techniques: Hops are often added early in the boil for bitterness, with smaller late additions for aroma. The focus is on achieving a harmonious balance between malt and hops.

Belgian Ales

Belgian Ales are known for their complex flavor profiles, which result from a combination of unique yeast strains and selective hop usage. Hops play a supportive role, enhancing the overall complexity without overshadowing the yeast-derived flavors.

Hop Characteristics: Herbal, spicy, floral, and earthy notes.
Popular Hop Varieties: Styrian Goldings, East Kent Goldings, Saaz, Tettnang.
Brewing Techniques: Moderate hop additions during the boil provide balance and complexity. Aromatic hops may be used sparingly to complement the yeast character.

Stouts and Porters

Stouts and Porters focus more on the malt profile, with hops playing a secondary role. Hop bitterness can help balance the rich roasted malt flavor, but the hop aroma is usually weak.

Hop Characteristics: Earthy, herbal, and sometimes floral notes.
Popular Hop Varieties: Fuggle, East Kent Goldings, Northern Brewer, Challenger.
Brewing Techniques: Hops are primarily added early in the boil for bitterness. Any late additions are minimal, focusing on enhancing the malt-driven profile.

Hops significantly influence the flavor and aroma of beer, and their role varies widely across different beer styles. In Pale Ales and IPAs, hops are the star, contributing bold and complex flavors. In Lagers and Pilsners, hops provide a crisp, balanced bitterness that enhances drinkability. Belgian Ales use hops to add subtle complexity, complementing the yeast character. In Stouts and Porters, hops provide the necessary bitterness to balance rich malt flavors. Understanding the role of hops in these styles allows brewers to craft beers with diverse and distinct profiles, catering to a wide range of tastes and preferences.

Summary

Hops play a crucial role in shaping the flavor, aroma, and overall character of beer. Through their complex chemistry, hops contribute bitterness, essential oils, and polyphenols, each influencing the beer in unique ways. The variety of hops—bittering, aroma, and dual-purpose—allows brewers to tailor their creations to achieve desired bitterness levels, flavors, and aromatic profiles. Techniques such as hopback, whirlpool hopping, cryo hops, and double dry hopping further enhance hop characteristics, maximizing their impact on the beer. Different beer styles utilize hops distinctively: Pale Ales and IPAs showcase bold hop flavors and aromas, Lagers and Pilsners achieve balance and crispness, Belgian Ales use hops to complement yeast complexities, and Stouts and Porters rely on hops for subtle bitterness against rich malt backgrounds. Understanding the multifaceted role of hops enables brewers to craft diverse and flavorful beers, highlighting the artistry and science behind brewing.

Get A Turnkey Brewery Solutions

At ZYB Craft, we understand the intricacies of brewing and the pivotal role hops play in creating exceptional beer. Our turnkey brewery solutions are designed to cater to every aspect of your brewing needs, ensuring you can harness the full potential of hops to craft beers with unparalleled flavor and aroma. Whether you are a startup brewery or an established brand looking to expand, our comprehensive services include state-of-the-art brewery equipment, customized brewhouse equipment, and expert consultancy.
We provide advanced hop management systems that allow precise control over hop additions, from bittering to dry hopping, ensuring consistency and quality in every batch. Our solutions are tailored to enhance the efficiency and scalability of your brewing operations while maintaining the highest standards of quality. Partner with ZYB Craft to elevate your brewing process and produce beers that captivate and delight you, leveraging our expertise and innovative solutions to achieve your brewing aspirations.

Products

Recent Blog

Factors Affecting the Initial Investment in Fermentation Tanks

2024-10-01

Automatic VS Manual Brewing Systems: Comprehensive Analysis

2024-09-28

How To Choose The Right Heat Source For Brewhouse?

2024-09-25