WO2001035768A1

WO2001035768A1 - Flavor freshness enhancers

Info

Publication number: WO2001035768A1
Application number: PCT/US2000/031267
Authority: WO
Inventors: Lawrence L. Buckholz, Jr.; Brian Byrne
Original assignee: J.Manheimer, Inc.
Priority date: 1999-11-15
Filing date: 2000-11-14
Publication date: 2001-05-25
Also published as: AU1607701A

Abstract

The invention relates to flavoring compositions which comprise a cysteine adduct obtainable by the reaction of an ester or salt thereof and an α, β-unsaturated carbonyl-containing compound. This invention also relates to food products, oral care products, tobacco products, pharmaceuticals, confectioneries and flavoring agents which can have the inventive products.

Description

TITLE OF THE INVENTION

FLAVOR FRESHNESS ENHANCERS RELATED APPLICATIONS

This application is related to application USSN 09/438,243, filed November 12, 1999, entitled Citrus Flavor and Aroma Compositions, and to application USSN 09/441,159, filed November 15, 1999, entitled Mint Flavor Compositions, both filed concurrently herewith, and both of which, as well as all documents cited in those applications and those cited herein are hereby incorporated by reference.

FIELD OF THE INVENTION This invention relates to flavoring compositions which comprise a cysteine adduct obtainable by the reaction of cysteine or an ester or salt thereof and an α, β-unsaturated carbonyl-containing compound. This invention also relates to food products, oral care products, tobacco products, confectioneries, pharmaceuticals and flavoring agents which contain the inventive adducts.

BACKGROUND OF THE INVENTION There is a constant interest in the flavor art to increase the flavor of processed foodstuffs so that the foods have a fresh taste. This is particularly difficult when the flavors have been blended together from component chemical ingredients making up that particular flavor. Flavor components found in fresh picked fruits and vegetables or freshly prepared foods contain a larger number of chemical components, not all of which have been identified. The category of flavor materials best known, identified, synthesized and used in commercial flavor manufacturing are the volatile flavor components. However, non- volatile components, because of their difficulty to isolate and identify, received little attention in the art until recently.

The freshness of fruits, vegetables and prepared foods has been the subject of interest throughout the food industry for many generations. From fresh squeezed orange juice to fresh brewed coffee, the question remains. "What is responsible for the freshness?" and "Where does it go with time or processing?". In an effort to answer these questions, fresh picked materials and materials that are in the process of ripening prior to picking were investigated vigorously by Mookherjee and others. See, e.g. U.S. Patents 5,269,169; 5,355,718; 5,369,978; 5,367,899 and

5,321,005.

While the details used to investigate the flavor development, or changes as ripening occurs, vary from investigator to investigator, the methodologies are basically similar. The techniques rely upon the separation of the volatile flavor components from the growing organic matter, the separation of the individual volatile flavor components from each other (usually by gas chromatography), and the identification of the individual components (usually by mass spectrometry). The bulk of the literature discusses materials that are volatile and thermally stable enough to be identified by a mass spectral identification. The materials which are either nonvolatile and/or, thermally unstable are the most difficult to identify. Thus isolation and identification of these materials has received little attention until recently.

In more recent times, a family of bound flavor materials, known as glycosides, has been identified. The contribution of these materials to the generation of flavor has been studied, as well as, the use of enzymes to free more of the sugar bound flavor molecules. The purpose of doing this is to enhance the flavor of juices by increasing the volatile flavor molecules. From those studies, it appears that many of the flavor molecules in ripening foods liberate upon enzymatic action during the ripening process.

The impact of glycosides upon the taste impression of a flavor has not been studied at length in the art. While not wishing to be bound by theory, we have speculated that flavor molecules, similar to the glycosides, are bound up as addition products to amino acids and proteins. Some of the amino acid bound flavor molecules remain bound material during the ripening process similar to the glycosides. Upon thermal processing these materials, which are far more delicate than glycosides, decompose to give volatile flavor molecules and the parent amino acid or protein. It is believed that during the ripening process the amino acid bound flavor materials are enzymatically converted into volatile sulfur flavor compounds. One recent patent (U.S. 5,128,194) uses this strategy to make natural sulfur chemicals. We have discovered that by preparing model systems using the amino acid, L-cysteine, and α, β-unsaturated flavor molecules that a unique group of nonvolatile flavor adducts are prepared. We have found that the amino acid bound adducts are particularly important in imparting the flavor characteristics frequently lost upon processing. These lost characteristics are generally referred to as freshness components of the flavor or taste and are equated with "fresh picked", "fresh squeezed", "vine ripened" and the like. While these materials have been identified as precursors to volatile sulfur molecules in wine, the importance of the amino acid bound materials as flavorants has heretofore gone undiscovered. In U.S. Patent 5,182,194, Kerkenaar et al. disclose the preparation of the pulegone-cysteine adduct. In contrast to the present invention, this adduct is disclosed merely as a chemical intermediate to prepare p-mentha-8-thiol-3-one by biological treatment of the adduct. No mention is made of the use of the cysteine adduct itself as a non-volatile flavorant material. Tominaga et al., in J. Agric. Food Chem., col. 46, pp. 5715-5719 (1998), disclose the preparation of 4-cysteinyl-4-methylpentan-2-one, 4-cysteinyl-4- methylpentan-2-ol, and 3-cysteinyl hexan-1-ol in order to identify flavor precursors involved in the aroma of wine. While the article alleges that those compounds are present in wine must and that they are converted during fermentation to "volatile sulfur flavor precursors...", no mention is made of these non volatile sulfur flavor precursors as flavorants in their own right. Moreover, no mention is made of these materials as flavorants or flavor enhancers to the overall flavor of wine.

We have unexpectedly found that the adduct, obtained from the reaction of cysteine, its salt and esters with an unsaturated flavor component, imparts freshness and flavors to foodstuffs and tobacco products when the adduct is added to these components. Furthermore, we have discovered that the inventive adducts enhance the flavor of flavoring agents, which then are used in foodstuffs, tobacco products, pharmaceutical, and oral care products. SUMMARY OF THE INVENTION

This invention provides for a flavoring composition which comprises optionally a flavoring agent and a cysteine adduct obtainable by the reaction of cysteine, or a salt or ester thereof, with an ,β-unsaturated carbonyl-containing compound. This invention further provides for food products, tobacco products, oral care products, pharmaceuticals, confectioneries and flavoring agents which contain the inventive flavoring compositions. Additionally, this invention provides for foodstuffs, tobacco products, oral care products, pharmaceuticals and flavoring agents which comprise a flavor enhancing composition comprising a cysteine adduct obtainable by the reaction of cysteine, or a salt or ester thereof, with an α, β-unsaturated carbonyl-containing compound as well as a method of enhancing the flavor of these products.

These and other embodiments are disclosed or are obvious from and encompassed by the following Detailed Description.

DETAILED DESCRIPTION

The cysteme adducts of the present invention relate to compounds of the formula

wherein:

R¹ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle;

R is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R³ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle;

R⁴ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; or

R¹, R², R³ or R⁴ together with one another form an optionally substituted cycloalkyl or cycloalkenyl ring, or an ester or salt of the compound.

These adducts of the present invention are obtainable by the reaction of cysteine (I) , or a salt or ester thereof,

with an α,β-unsaturated carbonyl compound, which include, for example compounds of the formula

wherein R¹, R², R , and R are defined above. Preferably, the optionally substituted alkyl, cycloalkyl, alkenyl, cycloalkenyl and aryl groups contain 1 to 20 carbon atoms with alkyl and alkenyl groups having from 1 to 10 carbon atoms and cycloalkyl groups having 3 to 10 carbon atoms being most preferred. Preferred substituted aryl groups are those containing 6 to 14 carbon atoms, with phenyl and naphthyl being the most preferred. The optionally substituted heterocyclic groups are preferably for example, cycloalkyl, cycloalkenyl, or aryl groups in which at least one carbon atom is replaced by S, N or O. Examples of such groups include piperdine, thiophene, furan, pyrrole, thiazole, oxazole, imidazole, isothiazole, isoxazole, pyrazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,3,4-triazole, 1,2,4-oxadiazole, 1,2,4-thiadiazole, 1,2,4-triazole,

1,2,3-triazole, 1,2,3,4-tetrazole, benzo[b]thiophene, benzo[b]furan, indole, benzo[c]thiophene, benzo[c] furan, isoindole, benzoxazole, benzothiazole, benzimidazole, benzisoxazole, benzisothiazole, benzopyrazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene, carbazole, pyridine, pyrazine, pyrimidine, pyridazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,4,5-triazine, quinoline, isoquinoline, quinoxaline, quinazoline, cinnoline, 1,8-naphthyridine, 1,5-naphthyridine,

1 ,6-naphthyridine, 1 ,7-naphthyridine, phthalazine, pyridopyrimidine, purine, pteridine or 4H-quinolizine.

Substituents for the alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, and heterocycle groups are those typically found in flavors. These substituents include functional groups such as alcohols, ketones, aldehydes, acids, esters, amines, etc.

Especially preferred substituents are Cι-C₂₀ alkyl, -OR⁵ or - NR⁶ R⁷, wherein R⁵R⁶ and

R⁷ each independently are hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle wherein the optionally substituents are those identified above.

Especially preferred adducts are those where:

-R¹ is CH₂CH[C(CH₃)=CH₂]CH₂- connected to the R_A position, R₂ is -H and R is -CH₃;

-R¹ is -CH₂CH₂CH₃, R₂, R₃, R₄ are -H; --R^JR² is -CH₃, R³ is -H and R⁴ is -CH₃;

-R¹ and R² is -CH₃, R³ is -CH₂CH₂CH(CH₃)CH₂- connected to the R⁴ position.

The corresponding basic and acid addition salts and the ester derivatives of these adducts are also contemplated. These salts are formed from the corresponding organic and inorganic acids and bases and include the customary hydrohahde, such as the hydrochloride salt, and phosphate salts. Esters formed from the corresponding alcohol or carboxylic acid moiety include alkyl esters having 1 to 20 carbon atoms with the acetate, proprionate and butyrate esters being most preferred.

The flavoring adducts used in the inventive flavoring compositions are prepared by the following reaction:

Scheme I

TTΓ

where amino acid section of the compounds of formula III are derived from cysteine, its esters and salts. This reaction is known in the art and is described, for example, in U.S. Patent No. 5,182,194. Cysteine is an amino acid used extensively in beef and chicken flavors, particularly for reaction flavors and Maillard products. Cysteine, as well as its salts and esters derivatives, is well known in the art and is described, for example in "The Merck Index", 10th ed., M. Wildholz, ed., Merck & Co., Inc., Rahway, NJ (1983). Processes for its syntheses are described, for example, in U.S. Patent 2,376,186; 2,406,362; and 2,449,303.

Particularly preferred are the inorganic and organic salts of cysteine, with cysteine hydrochloride being especially preferred. Also preferred are the carbocyclic acid alkyl esters of cysteine, with the methyl, ethyl, propyl, isopropyl, butyl and isobutyl esters being most preferred. These sources of cysteine are either commercially available or are obtained by processes known in the art. 7 the hydrochloride salt, and phosphate salts. Esters formed from the corresponding alcohol or carboxylic acid moiety include alkyl esters having 1 to 20 carbon atoms with the acetate, proprionate and butyrate esters being most preferred.

Scheme I

Particularly preferred are the inorganic and organic salts of cysteine, with cysteine hydrochloride being especially preferred. Also preferred are the carbocyclic acid alkyl esters of cysteine, with the methyl, ethyl, propyl, isopropyl, butyl and isobutyl esters being most preferred. These sources of cysteine are either commercially available or are obtained by processes known in the art. α, β-unsaturated carbonyl-containing compounds of formula II are also well known in the art and are either obtained commercially or by process known in the art. Examples of such compounds include:

Alpha-Irone Carvone

Cinnamic Acid

Cinnamic Aldehyde

Citral

Curcumin Damacenone

Damascone

2,4-Decadienal

3-Decen-2-one

2,5 Dimethyl-4-hydroxy-3 (2H) Furanone 2,5-Dimethyl-4-methoxy-3 (2H) Furanone

Ethyl Aconitate

Ethyl Acrylate

Ethyl Cinnamate

Ethyl 2,4-Decadienoate Ethyl Tiglate

Fumaric acid

2,4-Heptadienal

3-Hepten-2-one

2,4-Hexadienal 4-Hexen-3-one

2-Hexenoic Acid

Indigo

Alpha-Ionone

Beta-Ionone Isojasmone Jasmone

Mesityl Oxide o-Methoxy Cinnamic Aldehyle

Methyl Cinnamate 3-Methylcrotonic Acid

3-Methy-2-cyclohexen-3-one

5-Methyl-3-hexen-2-one

5 -Methyl-2-phenyl-2-hexenal

4-Methyl-2-phenyl-2-pentenal Myrtenal

Nookatone

2,4-Octadienal l-Octen-3-one

3-Octen-2-one l-Penten-3-one

3-Penten-2-one

4-Phenyl-3-buten-2-one

3-Phenyl-2-butenal

Pipeline Piperitone

Pulegone

Safronal

Sinensal

Tiglic acid trans-2-Butenal trans-2-Decenal trans-2-Dodecenal trans-2-Hexenal trans-2-Nonenal trans-2-Octenal 10 trans-2-Pentenal

2-Propenal trans-2-Undecenal

2,4-Undecadienal

The flavors contemplated in the present invention are any of the oils, flavors, or aromas known in the flavoring art. These oils, flavors, and aromas may be derived from natural sources or produced synthetically. These oils, flavors and aromas are obtained commercially or by known technique. Preferred flavors include citrus oils, such as lemon and orange oil, natural orange flavors, spearmint oil, peppermint oil, other mint oils and artificial reconstituted flavors.

The flavor and aroma compositions may be used in a wide range of products and fragrances such as of foodstuffs, tobacco products, pharmaceuticals, oral care products, sweeteners and cosmetics. Such products, as well as the amount of flavor or aroma to add to these products would be well known to one skilled in the art.

Especially preferred food products include beverages, such as orange juice or lemonade, confectioneries and chewing gums. Especially preferred oral care products include mouthwashes or toothpastes.

This invention also provides for a method of enhancing the flavor or aroma of a foodstuff, tobacco product, oral care product, pharmaceutical or flavoring agents by adding an adduct of formula III. The amount of adduct required to enhance the flavor depends on the product and determining the amount required would be well within the skill level of the practitioner in this art.

A better understanding of the present invention and of its many advantages will be had from the following examples, given by way of illustration

EXAMPLES

Example 1

d-Pulegone 152.23 g 11

1 -Cysteine Hydrochloride 157.66 g

Water 500.00 g

Ethanol 2,000.00 g

Sodium Bicarbonate 84.00 g

The 1 -cysteine hydrochloride and sodium bicarbonate were dissolved in water. The d- pulegone was dissolved in ethanol. The water and ethanol solutions were mixed together for 16 hours at room temperature, filtered and evaporated to dryness in vacuum. Example 2

The pulegone-cysteine adduct of Example #1 was diluted in one part to ninety-nine parts rectified Scotch Spearmint Oil. The resultant mixture was tasted at 10 ppm in sweetened water against a control containing 10 ppm rectified Scotch Spearmint Oil, only. All panelists selected the adduct as having a more "fresh picked" mint flavor, as well as having a stronger more intense flavor. Example 3 trans-2-Hexenal 98.15 g

1 -Cysteine Hydrochloride 157.66 g

Water 500.00 g

Ethanol 2,000.00 g

Sodium Bicarbonate 84.00 g

The 1 -cysteine hydrochloride and sodium bicarbonate were dissolved in water. The trans-2-Hexenal was dissolved in ethanol. The water and ethanol solutions were mixed together for 16 hours at room temperature, filtered and evaporated to dryness in vacuum.

Example 4 The trans-2-hexenal-cysteine adduct of Example #3 was diluted 0.1 part in 99.9 parts propylene glycol. To 100 grams tomato soup (Campbell Soup Company, Camden, NJ 08103) 0.10 grams of the propylene glycol solution was added. The resultant soup was 12 tasted against the untreated soup. All panelists selected the adduct containing soup as being stronger in tomato flavor. Additionally, comments were made as to "vine ripened" character and greater mouthfeel created by the adduct.

Example 5

Pipeline 285.32 g

1 -Cysteine Hydrochloride 157.66 g

Water 500.00 g

Ethanol 2,000.00 g

Sodium Bicarbonate 84.00 g

The 1 -cysteine hydrochloride and sodium bicarbonate were dissolved in water. The pipeline was dissolved in ethanol. The water and ethanol solutions were mixed together and heated to 80°C for one hour. Example 6

The piperine-cysteine adduct was tasted against pipeline both at 0.1 ppm in instant mashed potatoes (Potato Buds, General Mills, Minneapolis, MN 55440). The adduct had a stronger warming effect with an overall mouth warming, whereas piperine had more of a tongue biting effect. The mashed potatoes with the adduct were deemed by the panelists to be more like freshly prepared rather than instant. Example 7

Citral 152.23 g

1 -Cysteine Hydrochloride 157.66 g Water 500.00 g Alcohol 2,000.00 g

Sodium Bicarbonate 168.00 g

The 1 -cysteine hydrochloride and sodium bicarbonate (2 equivalents) were dissolved in water. The citral was dissolved in ethanol. The water and ethanol solutions were mixed 13 together at room temperature for 16 hours and filtered. The resultant red-black solution of the citral-cysteine sodium salt adduct was used as is.

Example 8

Control Treated

30.0 g 30.0 g Natural Orange Flavor WONF 11-80-4005-2 (J. Manheimer, Inc.)

0.0 g 1.0 g Product of Example #7

1.0 g 0.0 g Alcohol

Two Natural Orange Flavors were made up, one with treated Citral (Product of Example #7P and a Control, without treated material.

Both flavors were diluted into a beverage format for evaluation using the following formula. INGREDIENT AMOUNT High Fructose Corn Syrup 55, 76° Brix 300.0 ml

Sodium Benzoate, 25% (wt./vol.) Solution 3.5 ml

Citric Acid, 502 (wt./vol.) Solution 7.0 ml

Flavor (Treated and Control) 9.0 ml

Water 180.5 ml Carbonated Water, 2.8 to 3.0 volumes 2.500.0 ml

Total 3,000.0 ml

Initial tasting: Relative to the control, the adduct containing beverage has a fresh squeezed flavor, with enhanced sweetness and freshness. The overall impression is that of greater mouthfeel and tartness similar to fresh squeezed orange juice.

Tasting after holding beverage in a hot box (90°F) for 30 days: Relative to control, the treated flavor has more flavor retained with greater sweetness and fidelity of flavor.

The above description of the invention is intended to be illustrative and not limiting. Various changes or modification in the embodiment describe may occur to 14 those skilled in the art. These can be made without departing from the scope or spirit of the invention.

Claims

15What is claimed is:

1. A flavoring or aroma composition which comprises:

- a cysteine adduct of the formula

wherein:

R¹ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R² is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R³ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R⁴ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; or R¹, R², R³ or R⁴ together with one another form an optionally substituted cycloalkyl or cycloalkenyl ring, or an ester or salt of the compound. 16

2. The composition according to claim 1 wherein

R¹ is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted

Cι-C₂₀ cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, - OR⁵ or -NR⁶ R⁷;

R² is hydrogen, optionally substituted Cj-C₂o alkyl, optionally substituted

Ci-C₂₀ cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷; R³ is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted

C]-C o cycloalkyl, optionally substituted Cι-C ₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷;

R⁴ is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted Ci-C₂₀ cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷;

R¹, R², R³ or R⁴ together with one another form an optionally substituted Cι-C₂₀ cycloalkyl or cycloalkenyl ring, and the optionally substitutents are Ci- C₂₀ alkyl,

-OR⁵ or - NR⁶ R⁷, where

R⁵, R⁶, and R⁷ each independently are hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle or an ester or salt thereof.

3. The composition according to claim 1, wherein

R¹ and R⁴ together form -CH₂ CH[C(CH₃)=CH₂]CH₂-,

R² is H, and

R³ is CH₃.

4. The composition according to claim 1 , wherein 17 R¹ is -CH₂CH₂CH₃;

R² is H,

R³ is H,

R⁴ is H.

5. The composition according to claim 1, wherein

R* is CH₃; R² is CH₃; R³ is H; and R⁴ is CH₃.

6. The composition according to claim 1, wherein

R¹ is CH₃; R² is CH₃; R³ and R⁴ together for -CH₂CH₂CH(CH₃)CH₂-.

7. The composition according to claim 1 which further comprises an oil, flavor or aroma.

8. The composition according to claim 7, wherein the flavor is spearmint.

9. The composition according to claim 7, wherein the flavor is orange.

10. A food product, tobacco product, oral care product, confectionery or pharmaceutical which comprises a composition according to claim 1.

11. The food product according to claim 10 wherein the food product is a beverage or the confectionery is gum.

12. A food product, tobacco product, oral care product, confectionery or pharmaceutical which comprises a flavor composition comprising a cysteine adduct of the formula

18 wherein:

R¹ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R² is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle;

R³ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle;

13. A food product, tobacco product, oral care product, confectionery or pharmaceutical according to claim 12, wherein

R¹ is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted Ci-C₂₀ cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷;

R² is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted

C]-C₂₀ cycloalkyl, optionally substituted C]-C ₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are C]-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷;

R³ is hydrogen, optionally substituted Cι-C₂₀ alkyl, optionally substituted

Cι-C₂o cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are Cι-C₂₀ alkyl, - OR⁵ or -NR⁶ R⁷; 19 R⁴ is hydrogen, optionally substituted C]-C₂₀ alkyl, optionally substituted

Cι-C₂o cycloalkyl, optionally substituted Cι-C₂₀ alkenyl or optionally substituted phenyl, and the optionally substitutents are C1-C₂₀ alkyl, -

OR⁵ or -NR⁶ R⁷; R¹, R², R³ or R⁴ together with one another form an optionally substituted -C₂o cycloalkyl or cycloalkenyl ring, and the optionally substitutents are C

C₂₀ alkyl,

-OR⁵ or - NR⁶ R⁷, and

14. A food product, tobacco product, oral care product, confectionery or pharmaceutical according to claim 13 wherein R¹ and R⁴ together form -CH₂CH[C(CH₃)=CH₂]CH₂-,

R² is H, and R³ is CH₃.

15. A food product, tobacco product, oral care product, confectionery or pharmaceutical according to claim 13, wherein R¹ is -CH₂CH₂CH₃

R² is H,

R³ is H,

R⁴ is H.

16. A food product, tobacco product, oral care product, confectionery or pharmaceutical according to claim 13, wherein

R¹ is CH₃;

R² is CH₃; is H; and

R⁴ is CH₃. 20

17. A food product, tobacco product, oral care product, confectionery or pharmaceutical according to claim 13, wherein R¹ is CH₃; R² is CH₃; R³ and R⁴ together for -CH₂ CHCH(CH₃)CH-.

18. A method of enhancing the flavor or aroma of a food product, tobacco product, oral care product, pharmaceutical, confectionery or flavoring agent, which comprises adding to said food product, tobacco product, oral care product, pharmaceutical, confectionery or flavoring agent an adduct of the formula

wherein:

R¹ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R² is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; R³ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle;

R⁴ is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heterocycle; or R¹ , R², R³ or R⁴ together with one another form an optionally substituted cycloalkyl or cycloalkenyl ring, or an ester or salt of the adduct.