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Bittering agent

A bittering agent is a substance, either natural or synthetic, added to foods, beverages, or other products to impart a bitter taste, which can serve functional roles in flavor enhancement, preservation, or deterrence from consumption.^[1]^[2] These agents interact with human taste receptors, particularly TAS2R bitter receptors, to elicit an aversive response that evolutionarily protects against potentially toxic compounds, though in controlled culinary applications, bitterness balances sweetness and adds complexity to profiles.^[3]^[4] In the food and beverage industry, bittering agents are essential for creating distinctive tastes in products like beer, where hops—specifically their alpha-acids such as humulone—provide bitterness during boiling, contributing to flavor, aroma, stability, and foam retention while acting as a natural preservative.^[5]^[6] Quinine, derived from cinchona bark, serves as a classic example in tonic water, delivering its signature bitter tang at regulated low levels to avoid health risks while enhancing drinkability when mixed with spirits.^[7]^[8] Other natural sources include polyphenols, alkaloids, flavonoids, and herbal extracts like gentian or wormwood, used in cocktails, sodas, and digestive aids to modulate overall sensory experiences.^[4]^[9] Beyond culinary uses, bittering agents function as aversives in non-food items to enhance safety, with denatonium benzoate (branded as Bitrex)—recognized as the world's bitterest compound—added in trace amounts to household chemicals, antifreeze, and nail-biting deterrents to prevent accidental poisoning, especially in children, by triggering an immediate rejection reflex.^[2]^[10] These applications highlight the dual nature of bitterness: a sensory tool for gastronomic innovation and a protective mechanism in product formulation, governed by strict regulatory limits to ensure harmlessness at effective concentrations.^[11]

Definition and Properties

Definition

A bittering agent is a flavoring substance or compound added to foods, beverages, or other products to impart a bitter taste, often serving to balance sweetness, enhance overall flavor complexity, or fulfill functional roles such as preservation.^[12] These agents are distinct from other flavor enhancers, as they specifically target the gustatory perception of bitterness rather than aromas (via olfaction) or sweetness (via TAS1R receptors).^[13] Bitterness itself is one of the five basic tastes—alongside sweet, sour, salty, and umami—recognized by the human gustatory system. It is primarily detected by TAS2R bitter taste receptors, a family of G-protein-coupled receptors expressed in type II taste cells within the taste buds on the tongue's surface.^[13]^[14] These receptors respond to a wide array of structurally diverse compounds, triggering neural signals that convey the aversive yet nuanced sensation of bitterness, which evolutionarily helps avoid potentially toxic substances while allowing controlled incorporation for sensory balance.^[3] Bittering agents generally fall into broad categories such as natural plant extracts, isolated bitter compounds from botanical sources, and synthetic analogs designed to mimic natural bitterness.^[15]^[16] In applications like beer production, they contribute to flavor harmony by countering malt sweetness without dominating the profile.^[12]

Chemical and Sensory Properties

Bitterness in bittering agents arises from the activation of TAS2R receptors, a family of approximately 25 G-protein-coupled receptors (GPCRs) expressed on taste bud cells in the human tongue and palate. These receptors detect a diverse array of bitter compounds, triggering a signaling cascade involving gustducin, phospholipase C, and intracellular calcium release, which ultimately leads to the perception of bitterness.^[17]^[18] Key chemical properties of bittering agents include varying degrees of hydrophobicity, which influences their interaction with lipid-rich taste cell membranes and contributes to their broad structural diversity, ranging from alkaloids to peptides. Solubility profiles differ significantly; for instance, many are more soluble in alcohol than water, facilitating their use in beverages, while stability under heat and pH changes is crucial for processing—quinine, a prototypical bitter compound, maintains efficacy across a wide pH range but has limited aqueous solubility. Detection thresholds vary by compound, with quinine sulfate exhibiting a low bitterness threshold of approximately 0.0007% in solution, underscoring the high sensitivity of human taste systems to even trace amounts.^[19]^[20]^[21] Sensory evaluation of bitterness relies on trained panels that use standardized intensity scales, such as unstructured line scales (e.g., 0-150 mm) or category scales (e.g., 1-10), to quantify perceived intensity relative to reference standards like quinine solutions. These methods involve calibrated assessors who undergo repeated training to minimize variability, often employing descriptive analysis to differentiate bitterness sub-qualities from other tastes like astringency. While no direct analog to the Scoville scale exists for bitterness, adaptations using dilution series of bitter references allow for threshold determination in panel testing.^[22]^[23]^[24] Perception of bitterness is modulated by genetic factors, notably polymorphisms in the TAS2R38 gene, which determine "PROP taster status"—supertasters (homozygous for the sensitive allele) perceive compounds like 6-n-propylthiouracil (PROP) as intensely bitter, while non-tasters show reduced sensitivity. Age-related declines in taste bud density elevate bitterness thresholds by up to 2.5 times in older adults compared to younger individuals. Cultural differences also play a role, with variations in exposure leading to divergent tolerance levels; for example, populations with diets rich in bitter foods may exhibit higher acceptance thresholds than those with sweeter preferences.^[25]^[26]^[27]^[28]

Types of Bittering Agents

Natural Plant-Derived Agents

Natural plant-derived bittering agents are compounds extracted from various botanical sources, primarily roots, barks, and cones, that impart a characteristic bitter flavor due to bioactive secondary metabolites such as alkaloids, glycosides, and acids. These agents have been utilized for centuries in food and beverage production for their sensory properties and potential digestive benefits, with extraction typically involving methods like decoction, solvent extraction, or distillation to isolate the bitter principles while preserving natural variability in composition. Unlike synthetic counterparts, plant-derived agents exhibit batch-to-batch differences influenced by growing conditions, harvest timing, and processing, which contribute to their complex flavor profiles. Hops (Humulus lupulus), a climbing perennial in the Cannabaceae family native to Europe and Asia, serve as the primary bittering agent in beer production through their resinous cones. The key bitter compounds are alpha acids, collectively known as humulones (including humulone, cohumulone, and adhumulone), which constitute 2-18% of the dry weight depending on variety, with beta acids (lupulones) present in similar proportions but contributing less to bitterness. During brewing, these alpha acids isomerize under heat and alkaline conditions to form iso-alpha acids (isohumulones), which are more soluble and provide the stable bitterness essential to the beverage.^[29]^[30] Varieties such as Saaz, a noble hop from the Czech Republic with 2-5% alpha acids, are prized for subtle, earthy bitterness, while Cascade, an American aroma hop, offers 5-9% alpha acids with citrus notes.^[31]^[32] Hop extraction often employs solvent methods like ethanol or supercritical CO₂ to yield concentrates containing 5-15% alpha acids, enabling efficient bittering without vegetal matter.^[33] Gentian root, derived from Gentiana lutea, a perennial herb in the Gentianaceae family found in mountainous regions of Europe, is renowned for its intense bitterness used in tonics and digestive aids. The primary bitter compound is gentiopicrin, a secoiridoid glycoside that stimulates gastric secretions and comprises up to 2% of the root's dry matter, alongside other glycosides like amarogentin.^[34]^[35] Extraction typically involves decoction or alcohol infusion of the dried rhizomes and roots, yielding a potent tincture with 1-5% bitter principles, though yields vary with soil alkalinity and harvest age.^[36] Quassia, sourced from the wood and bark of Quassia amara, a tree in the Simaroubaceae family native to South America and the Caribbean, provides quassinoids such as quassin and neoquassin as its main bitter constituents, which are among the most potent natural bitters known, effective at concentrations below 10 ppm.^[37] These compounds, comprising 0.1-0.5% of the dry wood, have historically served as a hop substitute in beer for bitterness, particularly in regions where hops were scarce.^[38] Extraction methods include water decoction or ethanol percolation, producing yields of 0.14-1% total quassinoids from chipped wood.^[39] Other notable plant-derived agents include wormwood (Artemisia absinthium), a perennial in the Asteraceae family from Europe and Asia, where the sesquiterpene lactone absinthin (0.2-0.3% of leaf dry weight) delivers a sharp, aromatic bitterness used in liqueurs.^[40] Cinchona bark, from trees of the Cinchona genus (Rubiaceae) native to the Andes, contains quinine, an alkaloid at 0.5-2% concentration that imparts a distinctive cinchona bitterness in beverages like tonic water.^[41]^[42] For these, distillation or solvent extraction from leaves and bark respectively yields concentrated essences with 0.5-3% active bitters, emphasizing the role of natural variability in flavor intensity.^[43]

Synthetic and Artificial Agents

Synthetic bittering agents are laboratory-produced compounds designed to impart a controlled bitter taste, offering precision in applications where natural variability is undesirable. One prominent example is denatonium benzoate, recognized as the most potent known bitterant with an aversion threshold as low as 50 parts per billion (ppb). This quaternary ammonium compound was discovered accidentally in 1958 during research on local anesthetics by scientists at T. & H. Smith in Edinburgh, Scotland, and patented that year under the trademark Bitrex.^[44] It serves primarily as an aversive agent to deter ingestion of hazardous substances, such as in antifreeze, household cleaners, and denatured alcohol, where even trace amounts render products unpalatable.^[45] In beer production, synthetic hop analogs provide consistent bitterness by mimicking the iso-alpha acids derived from natural hops. Isomerized hop extracts involve processing alpha acids from hops through controlled isomerization to yield potassium salts of iso-alpha acids, ensuring stable bitterness levels without seasonal plant variations.^[46] For fully artificial alternatives, lab-synthesized iso-alpha acids have been developed via total chemical synthesis, enabling scalable production and customization for brewing.^[47] These compounds contribute up to 30-40% of a beer's total bitterness when added post-fermentation, maintaining flavor uniformity across batches.^[46] Other synthetic bitterants include sucrose octaacetate, a fully acetylated derivative of sucrose produced through esterification of sucrose with acetic anhydride, which yields a intensely bitter, non-sweet compound.^[48] This agent is employed in denaturing ethanol and as a deterrent in products like nail-biting preventives due to its threshold bitterness detectable at low concentrations. Picric acid derivatives, such as picramic acid, offer additional synthetic options; picric acid itself (2,4,6-trinitrophenol) is synthesized from phenol via nitration and exhibits extreme bitterness, historically used as a hop substitute in ales before its explosive properties limited broader adoption.^[49] These derivatives maintain the core bitter profile while allowing modifications for safety in targeted uses. The advantages of synthetic bittering agents over natural counterparts include high purity, which minimizes impurities and allergens; cost-effectiveness through large-scale chemical production; and reduced variability, enabling precise dosing in industrial settings.^[45] For instance, denatonium benzoate's production has scaled globally since its 1958 patent, supporting widespread use in safety formulations without reliance on botanical sources.^[44] Similarly, synthesized iso-alpha acids facilitate efficient brewing by avoiding crop-dependent fluctuations, enhancing product consistency and economic viability.^[47]

Primary Applications

In Beer Production

In beer production, hops serve as the primary bittering agent, added during the wort boil to isomerize their alpha acids into soluble iso-alpha acids that impart bitterness.^[50] This isomerization process typically requires a boil time of 60 to 90 minutes for optimal extraction, with the majority of bittering potential achieved within the first 20 minutes of boiling.^[51] The degree of bitterness is quantified using International Bitterness Units (IBU), estimated using formulas such as the Tinseth model: IBU = (alpha acid % × hop weight in oz × utilization × 74.89) / batch volume in gallons, where utilization depends on boil time, wort gravity, and other factors.^[52] Hops contribute to overall beer balance by counteracting the sweetness from malt sugars, creating a harmonious flavor profile essential for most styles.^[53] Additionally, hop-derived polyphenols enhance foam stability by interacting with beer proteins to form a persistent head, while providing antimicrobial properties that inhibit spoilage bacteria such as Lactobacillus during fermentation.^[54] Approximately 30% of beer polyphenols originate from hops, supporting oxidative stability and contributing to the beer's shelf life.^[55] Bitterness levels vary significantly across beer styles, tailored to stylistic expectations. India Pale Ales (IPAs) typically feature high bitterness at 40–70 IBU to emphasize hop character and balance robust malt profiles.^[56] In contrast, wheat beers maintain lower levels of 10–20 IBU, allowing subtle malt and yeast-derived flavors to dominate without overwhelming bitterness.^[57] Dry hopping, where hops are added post-boil during fermentation or conditioning, introduces aroma and flavor without significantly increasing IBU, as alpha acids remain un-isomerized.^[58] In gluten-free or historical brewing contexts, alternatives to hops include bitter orange peel, which provides citrusy bitterness through essential oils and flavonoids, and herbal bitters such as yarrow or sweet gale used in traditional gruit ales to achieve balance and preservation.^[59]^[60] These substitutes mimic hop functionality in non-traditional beers, though they lack the standardized IBU measurement.^[61]

In Food and Non-Alcoholic Beverages

Bittering agents play a crucial role in non-alcoholic beverages and foods by imparting complexity and balance to flavors. In tonic water, a popular mixer, quinine serves as the primary bittering agent, providing a distinctive sharp bitterness that pairs well with citrus and sweetness; regulatory standards limit its concentration to a maximum of 83 mg/L to maintain safety while achieving the desired sensory profile.^[62] Similarly, gentian root extract is a key component in aromatic bitters such as Angostura, where it delivers intense bitterness in small doses—typically a few drops per serving—to elevate the drink's depth without dominating other notes like spice or herbal undertones.^[63] In food applications, natural bittering agents from plants enhance culinary dishes by adding layers of flavor. Bitter melon (Momordica charantia), a staple in Asian cuisine, introduces a characteristic bitterness to stir-fries, soups, and curries, where its compounds like momordicin contribute a refreshing, slightly astringent taste that complements savory elements and is often prepared by salting to moderate intensity.^[64] In chocolate production, theobromine present in cacao nibs acts as a natural bittering agent, imparting the robust bitterness essential to dark chocolate's profile; during processing steps like roasting and conching, its levels are managed to balance against sweetness and acidity for optimal mouthfeel and appeal.^[65] Bittering agents also aid in masking off-flavors in functional foods and supplements, particularly those with low-calorie sweeteners or added vitamins that can exhibit metallic or astringent notes. By introducing controlled bitterness, these agents create flavor synergy that rounds out undesirable tastes, improving palatability in products like diet beverages and chewable vitamins without adding significant calories.^[66] Dosage levels of bittering agents are carefully calibrated to achieve sensory impact while avoiding excess. For instance, gentian extracts in liqueurs are used at low concentrations, where they elicit a potent bitter response detectable at even lower thresholds, enhancing the beverage's complexity and stimulating appetite through activation of taste receptors.^[67] This ensures the bitterness integrates harmoniously, contributing to a balanced aftertaste and overall recipe harmony in both savory and sweet preparations.^[68]

Other Applications

In Pharmaceuticals and Medicine

In pharmaceuticals, bittering agents play a dual role: masking the inherent bitterness of active pharmaceutical ingredients (APIs) to improve patient compliance, particularly in pediatric formulations, and intentionally adding extreme bitterness to deter accidental or abusive ingestion. For taste masking, bitter-blockers such as adenosine 5'-monophosphate (AMP) and sodium gluconate interact directly with TAS2R bitter taste receptors at the cellular level, reducing the perception of bitterness without altering the drug's efficacy. These agents are especially valuable in liquid or orodispersible pediatric medicines, where children's heightened sensitivity to bitter tastes—due to genetic variations in TAS2R38 receptors—often leads to refusal and incomplete treatment courses, with over 90% of pediatricians citing palatability as a major barrier. Cyclodextrins, another masking approach, form inclusion complexes with bitter APIs like cetirizine or naringin, halving perceived bitterness at concentrations as low as 0.5%, thereby enhancing acceptability in formulations for young patients.^[69]^[70]^[71] Conversely, synthetic bittering agents like denatonium benzoate are incorporated into drug coatings or syrups to impart an intensely aversive taste, detectable at concentrations as low as 50 parts per billion, primarily to prevent pediatric overdoses by discouraging mistaken consumption as candy. This strategy is applied in certain over-the-counter liquid medications and formulations, where the added bitterness signals potential toxicity and promotes safe handling, though it does not mitigate the underlying chemical risks. In abuse-deterrent formulations for opioids or stimulants, denatonium similarly discourages misuse by rendering tampering or non-oral routes unpalatable.^[72]^[73] Therapeutic applications of natural bittering agents leverage their physiological effects beyond mere taste. Herbal bitters derived from gentian root (Gentiana lutea), containing gentiopicrin and amarogentin, stimulate digestive secretions by activating bitter taste receptors in the gastrointestinal tract, promoting saliva production, gastric acid, and enzyme release to aid indigestion, poor appetite, and low stomach acidity. Traditionally dosed as 1–3 ml of tincture before meals, gentian remains a component in modern herbal supplements for these purposes, with contraindications for conditions like peptic ulcers. Quinine, isolated from cinchona bark in 1820 by Pierre Pelletier and Joseph Caventou, exemplifies a bitter alkaloid's medicinal potency as the first specific antimalarial drug, revolutionizing treatment by targeting Plasmodium parasites and remaining relevant in combination therapies despite resistance concerns.^[74]^[75] Emerging research explores bitter compounds' role in appetite regulation, with gastrointestinal delivery of agents like gentian-derived bitters or hop extracts showing potential to modulate hunger hormones such as ghrelin and motilin, leading to reduced energy intake in some human trials. For instance, microencapsulated bitter compounds from Gentiana lutea decreased daily caloric consumption by stimulating gut bitter receptors, suggesting applications in obesity management, though systematic reviews indicate inconsistent effects across studies and call for further validation. Historically, wormwood (Artemisia absinthium), a key bitter in absinthe, was valued in ancient and medieval medicine for digestive relief, treating stomach pain, jaundice, and parasitic infections, with its thujone content purportedly enhancing vitality in early 19th-century tonics before recreational associations overshadowed these uses.^[76]^[77]^[78]

In Cosmetics and Tobacco Products

Bittering agents find niche applications in cosmetics, where they serve as deterrents for unwanted habits and stimulants for scalp health. Denatonium benzoate, the most bitter substance known, is commonly added to nail polishes designed to discourage nail-biting and thumb-sucking, especially among children, by producing an immediate, unpleasant taste upon contact with the mouth.^[79] Commercial products like Mavala Stop incorporate this compound at low concentrations, allowing the polish to function as both a cosmetic coating and a behavioral aid without altering appearance or causing harm.^[80] Similarly, quinine, derived from cinchona bark, is utilized in hair tonics to stimulate scalp circulation and support hair follicle health, leveraging its mild bitter profile for invigorating effects in formulations like Clubman Eau de Quinine.^[81] These uses highlight the agents' role in enhancing product functionality while prioritizing safety and efficacy in personal care routines. In tobacco products, bittering agents play a dual role in flavor modulation and sensory perception. Nicotine imparts a natural bitterness to tobacco smoke, which can deter novice users, but manufacturers often employ additives such as licorice root extracts to counteract this harshness, imparting sweetness and a smoother, more rounded taste that improves palatability.^[82] Licorice, containing glycyrrhizin, is added at levels up to 5% in some blends without significantly altering smoke chemistry, though higher concentrations may elevate certain toxicants.^[83] Regulatory efforts in various regions have explored reducing masking agents to enhance the inherent bitterness and diminish appeal among youth, aligning with campaigns to curb initiation of smoking by amplifying the unpalatable aspects of tobacco.^[84] Beyond personal care and tobacco, bittering agents like denatonium benzoate are incorporated into animal repellents and household cleaners as aversive components to prevent unintended ingestion. At concentrations of 10-50 ppm, denatonium renders these products unpalatable to children, pets, and wildlife, deterring access to potentially hazardous substances such as antifreeze or detergents without affecting utility.^[72] This application exploits the compound's detection threshold as low as 50 parts per billion, ensuring broad deterrence while remaining non-toxic.^[85] Post-1990s developments have expanded these applications, spurred by heightened focus on child safety and public health initiatives against smoking. Innovations in denatonium formulations for cosmetics and household items emerged in response to poisoning prevention efforts, with U.S. agencies evaluating its efficacy in reducing accidental exposures.^[86] Concurrently, anti-smoking campaigns have influenced tobacco additive regulations, promoting formulations that preserve or accentuate bitterness to target youth deterrence, reflecting a shift toward harm reduction in non-food sectors.^[87]

History and Regulation

Historical Development

The use of bittering agents traces back to ancient civilizations, where bitter herbs played a central role in medicinal practices. In ancient Egypt around 2000 BCE, healers incorporated bitter plants, such as coriander, mint, sage, and other botanicals, into remedies often mixed with wine or beer to treat digestive ailments, fevers, and infections, as evidenced by archaeological findings of medicinal jars containing these mixtures.^[88] By the time of ancient Greece, gentian root (Gentiana lutea) emerged as a prominent bitter agent, named after King Gentius of Illyria who reportedly discovered its therapeutic properties around 167 BCE; Greek physicians like Dioscorides documented its use in the 1st century CE for stimulating digestion, reducing fevers, and countering poisons.^[89] A significant milestone in the application of bittering agents to beverages occurred in 1516 with the Bavarian Reinheitsgebot, or beer purity law, which mandated that beer be brewed using only water, barley, and hops, thereby standardizing hops (Humulus lupulus) as the primary bittering agent in European brewing to ensure quality and prevent adulteration.^[90] In the 19th century, the isolation of quinine from cinchona bark in 1820 by French chemists Pierre Joseph Pelletier and Joseph Bienaimé Caventou revolutionized bittering in non-alcoholic contexts, leading to the development of tonic water in the mid-1800s as a malaria prophylactic for British colonial troops in India, where quinine's intense bitterness was diluted with sugar and carbonation.^[91] The 20th century saw shifts toward synthetic and modified bittering agents amid regulatory and economic pressures. During the U.S. Prohibition era (1920–1933), aromatic bitters—traditionally alcohol-based—were reformulated into non-alcoholic "medicinal" tonics to comply with bans on intoxicating beverages, allowing their continued sale as patent medicines for digestive relief while preserving their role in clandestine cocktails.^[92] Post-World War II, the adoption of hop extracts in the 1950s marked an industrial advancement, enabling brewers to achieve consistent bitterness and flavor efficiency without relying on whole hops, which were scarce due to wartime disruptions.^[93] In 1958, denatonium benzoate was accidentally discovered by researchers at Macfarlan Smith in Edinburgh during local anesthetic studies, becoming the most bitter synthetic compound known and widely used thereafter to denature products like antifreeze.^[94] Cultural perceptions of bittering agents also evolved, exemplified by the 1912 U.S. ban on absinthe, a spirit bittered with wormwood (Artemisia absinthium) containing thujone, which was vilified as causing hallucinations and insanity amid moral panics; subsequent analyses in the late 20th century revealed thujone levels in historical absinthes were too low for such effects, leading to the ban's lifting in 2007.^[95]

Modern Regulations and Safety Standards

In the United States, the Food and Drug Administration (FDA) classifies extracts, essential oils, and natural extractives of hops (Humulus lupulus L.) as Generally Recognized as Safe (GRAS) for use as direct human food ingredients, allowing their incorporation in various food products without additional premarket approval under specific conditions.^[96] Quinine salts, such as quinine sulfate and quinine hydrochloride, are affirmed as GRAS by the Flavor and Extract Manufacturers Association (FEMA) for use as flavoring agents in food, though the FDA regulates quinine as a food additive with a maximum limit of 83 parts per million (ppm) in carbonated beverages to ensure safety.^[97]^[98] Denatonium benzoate, a synthetic bittering agent, is approved for use as an aversive denaturant in alcohol-based products like hand sanitizers under FDA regulations for over-the-counter drugs (27 CFR Part 21), reflecting its role as an aversive agent rather than a primary food flavorant.^[99] In the European Union, regulations under Commission Regulation (EU) No 1334/2008 establish maximum levels for quinine in non-alcoholic beverages at 100 mg/L, particularly for tonic and bitter drinks, to mitigate potential health risks from excessive consumption.^[100] Hop-derived products do not require mandatory allergen labeling under EU Regulation 1169/2011, as hops are not among the 14 major allergens listed, though voluntary disclosure may occur for transparency in beer and related foods.^[101] The World Health Organization (WHO) does not issue specific guidelines for bittering agents but aligns with general food safety standards under the Codex Alimentarius, emphasizing limits on additives like quinine to prevent toxicity in beverages. Toxicity assessments highlight the need for regulated use, with quinine exhibiting an oral LD50 of approximately 351 mg/kg in rats, indicating moderate acute toxicity, while human overdoses as low as 2-4 g can induce severe effects.^[102] Rare side effects from quinine overuse include cinchonism, characterized by tinnitus, nausea, vertigo, and visual disturbances, which typically resolve upon discontinuation but can lead to permanent auditory or visual impairment in extreme cases.^[103] In the 2020s, regulatory focus has shifted toward sustainability amid climate change impacts on hop production, with studies showing yield reductions of up to 20% due to rising temperatures and droughts in key regions like Europe and the United States.^[104] The EU's Corporate Sustainability Reporting Directive (CSRD) mandates large companies to disclose supply chain environmental impacts, encouraging sustainable sourcing of hops and exploration of synthetic bittering alternatives to reduce reliance on climate-vulnerable crops.^[105]

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Jul 2, 2002 · Commercial “quassin” from Quassia amara is known to contain a mixture of the bitter principles (quassinoids), like quassin, neoquassin, and ...Missing: Sweden beer
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(PDF) Application of Pau-tenente (Quassia amara L.) as Hop ...
Apr 14, 2020 · Quassia amara L. is a shrub belonging to Simaroubaceae family. The stem cork of this plant contains bitter principles of quassinoids (Quassin ...Missing: Sweden | Show results with:Sweden
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US8710247B2 - Process to extract quassinoids - Google Patents
Analysis of constituents in Jamaican quassia extract, a natural bittering agent. The percentages of total bitter substances are reported to range from 0.14 to ...Missing: Sweden beer
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Wormwood - Sensatonics
Wormwood contains many bitter substances (especially absinthin) and an essential oil that is rich in thujone (thujone has a molecular structure similar to THC).
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Cinchona Bark - an overview | ScienceDirect Topics
Cinchona bark is defined as the source of quinine, an alkaloid compound isolated in the 19th century, which was widely used as an anti-malarial agent, ...
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Cinchona Bark | Distiller Magazine
Aug 31, 2020 · Cinchona bark contains the bitter alkaloids quinine, quinidine ... Bark from South America tends to have lower quinine and total alkaloid content ...
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Bitter plants used as substitute of Cinchona spp. (quina) in Brazilian ...
Oct 7, 2013 · Quinine, alkaloid present predominantly in the barks of Cinchona calisaya Wedd. and Cinchona succirubra Pav. ex Klotzsch is very bitter, and ...
[44]
[PDF] coagulation treatment to remove denatonium benzoate from water
Denatonium Benzoate as an Aversive/Bittering Agent ... The threshold of recognition for the bitter taste is 5 to 100 ppb, and the aversion threshold is between 10 ...
[45]
Our Story – Bitrex
Denatonium benzoate was discovered by accident in 1958 while our scientists were working on a new local anaesthetic at our site in Edinburgh, Scotland. A ...
[46]
Denatonium Benzoate: Uses and Safety - ChemicalBook
Dec 16, 2024 · Denatonium Benzoate (bitter) is currently used as an aversive agent, denaturing agent, food blocking agent and flavoring agent. See also. 4.
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Isomerized Hop Extract 30% - Hopsteiner
Limit use of product to 30% – 40% of total bitterness to avoid a noticeable change in the bitter quality · Post fermentation for best utilization and efficiency ...Missing: synthetic analogs
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The development of a commercially viable, robust total synthesis of the iso-α-acids would allow labeling and chemical derivatization of the hops bitter acids ...
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Sucrose octaacetate | 126-14-7 - ChemicalBook
Oct 15, 2025 · It is also used as a bittering agent, and is incorporated into preparations intended to deter nail-biting or thumb-sucking.
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Picric acid – Knowledge and References - Taylor & Francis
It is said that picric acid is employed as an adulterant in bitter ale instead of hops. Now, the colouring power of picric acid is so great, that even the ...
[51]
Chapter 5 - Hops - How to Brew
Bittering hop additions are boiled for 45-90 minutes to isomerize the alpha acids; the most common interval being one hour. There is some improvement in the ...
[52]
Hops: Start to Finish | Craft Beer & Brewing
Jul 7, 2018 · Of the potential bittering you could get out of the hops you add, a majority is produced in just about 20 minutes. At the same time, most hops ...
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Hop Utilization Models for Beer Brewing Compared - BeerSmith
Sep 23, 2021 · The bitterness of a beer contributed by hops in the boil is typically estimated using one of three major hop utilization equations. All three ...
[54]
[PDF] an abstract of the thesis of - Oregon State University
Aug 18, 2017 · 32,49 Although hops have many roles in beer flavor and stability, its ability to balance malt's sweetness is of primary importance. In food ...
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Physiological Mechanisms by Which the Functional Ingredients in ...
The foam stability depends on the balance of foaming components ... beer polyphenols originate from barley malt, with the remaining 30% from hops.<|separator|>
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21. IPA - Beer Judge Certification Program
Dry to medium-dry finish; residual sweetness should be low to none. The bitterness and hop flavor may linger into the aftertaste but should not be harsh. A very ...
[58]
IBU Beer Scale: What Does It Mean? | Sierra Nevada Brewing Co.
Mar 10, 2023 · American wheat beers, where our Sunny Little Thing lives, tend to keep the bitterness tame, landing in the 10–35 IBU range. New England IPAs, ...Missing: 40-70 dry<|separator|>
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Dry Hopping Effect on Bitterness and IBU Testing - Scott Janish
Humulinones introduced to beer via dry hopping imparts a “smoother” bitterness than iso-alpha-acids and are 66% less as bitter. Humulinones are more soluble ...Missing: synthetic isomerized<|control11|><|separator|>
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16 Herbs and Spices to add Flavor and Aroma to your Homebrew
Feb 22, 2017 · Bitter Orange Peel – One of the most popular herbs for brewing beer, they are used by many domestic breweries to duplicate Belgian beer styles.
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https://www.brewersofpa.org/alternatives-to-hops/
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Alternatives to Hops – Brewers of Pennsylvania
Alternatives to Hops · Rosemary (Rosmarinus officinalis) · Chamomile (dried) · Juniper Berries · Ginger · Caraway seed · Aniseed · Coriander · Orange Peel ...
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The secret history of Angostura Bitters - BBC
May 6, 2021 · The only listed ingredient on the label is gentian, a bitter-tasting root that has long been used in herbal tonics. And while the bark of ...
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A comprehensive review on bitter gourd (Momordica charantia L.) as ...
May 25, 2022 · ... used as flavouring agents in various Asian dishes. Fruits are cooked with other vegetables especially in soups for the slight bitter taste.
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From Cocoa to Chocolate: Effect of Processing on Flavanols and ...
Cocoa bean processing mainly results in the reduction in the flavanols and theobromine content of cocoa beans and cocoa-related products. This modifies the ...
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Flavor Masking Challenges and How to Solve Them
Apr 1, 2020 · Common flavor masking challenges include plant-based proteins, vitamins, minerals, amino acids, caffeine, and high-intensity sweeteners, which ...<|separator|>
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How Chemical and Sensorial Markers Reflect Gentian Geographic ...
Aug 5, 2020 · It should undoubtedly affect the sensory properties and act as a gentian geographic origin marker in the gentian macerated wines. The other ...
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Bitter-blockers as a taste masking strategy - ScienceDirect.com
As more knowledge is generated, the use of bitter-blocking compounds can be better directed and make the art of taste-masking more precise.
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Physical Approaches to Masking Bitter Taste: Lessons from Food ...
It is a common goal in both food and pharmaceutical science to formulate products with a bitter but healthful ingredient while reducing perceived bitterness.
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The Bad Taste of Medicines: Overview of Basic Research on Bitter ...
Many active pharmaceutical ingredients taste bitter and thus are aversive to children, as well as many adults. Encapsulation of the medicine in pill or tablet ...Ii. Taste Receptor... · 4. Behavioral Assays In... · 5. Behavioral Assays In...
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Taste Aversive Agents - Poison Control
Denatonium benzoate has an extremely bitter taste that can be detected at minute concentrations (as low as 50 parts per billion). It has thus rightfully earned ...
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Are drugs made bitter artificially to prevent being mistaken for candy?
Dec 17, 2020 · A bittering agent may be applied to therapeuticals to prevent pediatric poisonings, but many drugs inherently taste bitter by themselves.
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Gentian – Health Information Library | PeaceHealth
Gentian is a bitter herb thought to stimulate digestion by increasing saliva production and promoting stomach acid and digestive enzyme production. More. ...
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The History of Malaria Treatment | ISGlobal
Apr 23, 2019 · The active ingredient was first isolated and extracted from cinchona bark in 1820 by the French pharmacists Pierre Pelletier and Joseph Caventou ...
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Microencapsulated bitter compounds (from Gentiana lutea) reduce ...
Nov 10, 2016 · Mounting evidence showed that bitter-tasting compounds modulate eating behaviour through bitter taste receptors in the gastrointestinal ...
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The effect of gastrointestinal bitter sensing on appetite regulation ...
Jan 1, 2023 · The GI sensing of bitter compounds may alter the secretion of appetite-related hormones thereby reducing food intake, which may have potential use for managing ...
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Artemisia absinthium L.—Importance in the History of Medicine, the ...
The wormwood herb has been used to treat jaundice, constipation, obesity, splenomegaly, and also to treat anaemia, insomnia and bladder diseases. It has also ...
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Research on the effectiveness of denatonium benzoate as ... - PubMed
Denatonium benzoate was chosen as a potential deterrent based on its existing uses in alcohol as a denaturant and in thumb-sucking and nail-biting deterrent ...Missing: polish | Show results with:polish
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Mavala Stop review: This polish helped break my nail-biting habit
Oct 23, 2024 · The Mavala Stop polish has a typical ingredient list for nail polish, with the exception of added denatonium benzoate for the bitter taste, says ...
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quinine - CosIng - Cosmetics - GROWTH - European Commission
Quinine is an alkaloid from the bark of Cinchona officinalis. It conforms to the ... Cosmetics Regulation provisions, III/21. Functions. DENATURANT · HAIR ...
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Nicotine Self-Administration With Tobacco Flavor Additives in Male ...
Menthol and licorice are tobacco flavoring agents also found in sweet foods (eg, candy and ice cream), making them putative CRs before they are consumed in ...
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Toxicologic evaluation of licorice extract as a cigarette ingredient
Licorice extract at < or =5% does not significantly alter smoke chemistry or biological effects. Higher levels increase some smoke constituents, but no ...
[85]
Coolants, organic acids, flavourings and other additives that ...
Sep 27, 2024 · Some additives counteract the harshness and bitterness of tobacco and nicotine product aerosols, making them easier to inhale.Missing: root | Show results with:root
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Denatonium Benzoate: The Bitterest Compound Known to Science
Jul 1, 2024 · The primary characteristic of denatonium benzoate is its extreme bitterness. Its detection threshold is as low as 0.05 ppm (parts per million), ...
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[PDF] Memorandum - Consumer Product Safety Commission
Jul 20, 2022 · In the past, DB was an active ingredient in nail-biting and thumb-sucking deterrents. The Food and Drug Administration removed the approval ...
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[PDF] Additives in tobacco products
Additives are substances added to tobacco to make it palatable, control burning, keep it moist, mask bitter taste, and make smoke milder.<|control11|><|separator|>
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Apr 13, 2009 · An ancient remedy: Bitter herbs and sweet wine. Jars suggest early Egyptians mixed medicinal plants into alcoholic beverage. Share this: Share ...
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Medicinal, biological and phytochemical properties of Gentiana ...
Jan 28, 2017 · The plaster of the root with vinegar was beneficial for bites of poisonous animals such as Scorpion and Pit viper, and also for healing injuries ...
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Apr 22, 2016 · So the law now states that malted grains, hops, water and yeast may be used - but nothing else.
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Oct 19, 2019 · The bitter flavouring of tonic water comes from an alkaloid called quinine which is extracted from the bark of the Andean fever tree (Cinchona spp.).
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Oct 2, 2019 · When alcohol manufacturing and consumption were legal and legion, bitters were produced by firms that were usually totally unafiliated with ...
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Apr 17, 2013 · This unreactive, colourless, odourless compound was first produced accidentally in 1958 by Scottish pharmaceutical manufacturer T & H Smith ...Missing: invention | Show results with:invention
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Oct 5, 2010 · Many now believe it unlikely that thujone—at least in the small amounts found in absinthe—can have a toxic effect.Missing: debunked | Show results with:debunked
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[PDF] Safety Assessment of Humulus Lupulus (Hops)-Extract and Oil as ...
The FDA determined that essential oils, oleoresins (solvent-free), and natural extractives (including distillates) of Humulus lupulus L. (hops) are GRAS for ...
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FEMA GRAS - Flavor and Extract Manufacturers Association
The FEMA Expert Panel has not evaluated quinine free base (free amine quinine) so it itself is not considered GRAS. FEXPAN evaluated the sulfate and chloride ...
[99]
21 CFR 172.575 -- Quinine. - eCFR
In carbonated beverages as a flavor, Not to exceed 83 parts per million, as quinine. Label shall bear a prominent declaration of the presence of quinine either ...Missing: GRAS | Show results with:GRAS
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[PDF] Policy for Temporary Compounding of Certain Alcohol-Based Hand ...
Mar 25, 2020 · An interim upper limit of 50 ppm is based on available toxicity ... 46 Denatonium benzoate can be added as either a solid or in liquid ...
[101]
Three quinine salts from the Priority list from chemical group 30
May 17, 1995 · The use of flavourings is regulated under Regulation (EC) No 1334/2008 of the European Parliament and Council of 16 December 20084 on ...
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[PDF] Barth Haas Hops - Castle Malting
Therefore, according to EU regulation 1169/2011 our hops and hop products are not subject to compulsory allergen labelling. We hereby certify that all hops ...
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[PDF] Quinine - SAFETY DATA SHEET
Oct 7, 2014 · LD50 Oral. LD50 Dermal. LC50 Inhalation. Quinine. 351 mg/kg (Rat). Not ... Safety, health and environmental regulations/legislation specific for ...
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Cinchonism - StatPearls - NCBI Bookshelf - NIH
Cinchonism is a collection of symptoms stemming from the ingestion of quinoline derivatives and their subsequent neural, retinal, and auditory toxicity.Missing: LD50 | Show results with:LD50
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Climate-induced decline in the quality and quantity of European ...
Oct 10, 2023 · To identify the current and future impacts of climate change on aromatic hops, we selected important hop-growing areas in Germany (DE), Czechia ...Missing: sourcing 2020s
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EU Supply Chain Sustainability Regulations Are Reshaping ...
Feb 26, 2025 · The CSRD requires companies to disclose detailed information on their environmental and social impacts, using standardized European Sustaina ...<|control11|><|separator|>