CA1121651A - 2,5-dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones, mixtures of same and organoleptic uses thereof - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Described are the novel compounds having the structures:

;

;

and mixtures of four 2,5-dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones which furanones have the structures:

;

;

;and a process for producing same; and a process comprising adding to a foodstuff an amount sufficient to augment the flavor aroma of such foodstuff of one of the above-mentioned novel compounds or of a mixture of the four 2,5- dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones having the structures:

;

;

;and

Description

1L6-Sl BACKGROUND OF THE INVENTION

1. Field of the Invention .
This invention relates to 2,5-dialkyl dihydrofuranones . and 2,4,5-trialkyl dihydrofuranones and uses thereof in augmenting or enhancing foodstuffs, toothpastes, medicinal products and chewing gum flavors and aromas.

`10 2. Description of the Prior Art .
. There has been considerable work performed relating to sub-stances which can be used to impart, (or enhance) flavors to (or : in) various foodstuffs, chewing gums and toothpastes. These sub-stances are used to diminish natural materials, some of which may be in short supply, and to provide more uniform properties in the . finished product. Sweet, brown sugar, pineapple-like, caramel, .~ buttery, scolded butter-like, dried hazelnut and earthy aromas, - ~ ~ and sweet, brown sugar-like, pineapple-like, caramel, buttery, cheese-like, roasted, vanilla-like, dried hazelnut and earthy tastes are desirable for many uses in foodstuff flavors, chewing '- ~gum flavors and toothpaste flavors as well as foodstuffs per se,chewing fums per se and toothpastes per se, for example, maple, , j , .
.. s ~ caramel, vanilla, butterscotch, rum, dairy, cereal, pineapple, :~^-.25 roasted almond, and mushroom flavored foodstuffs.
~ German Offenlegungsschrift 2,359,891, published on :........ June 6, 1974 entitled "2-alkyl-3(2H)-furanones" discloses the . use of individual compounds having the generic structure:
~ "'; ' .
: 30 !' ~ , ~

. 35 ~ ~ C) ~' . ``

.
: ~ .
'' ..
.',~`
~' "
,'. . ~
. .~

, ;~. .
.. , ~
".' ~
i .

` `` ilZi~iSl .: -2-`'' wherein Rl is hydrogen, hydroxyl, carboxylic acid, or carboxylic acid ester and wherein R2 is Cl-C4 alkyl and wherein R3 is hydrogen, or Cl-C7 alkyl for use in food-stuffs and foodstuff flavors. The specific compound having . 5 the structure:

. /0 . h~
'~10 '' ' ~:~ ic also disclosed in said German Offenlegungsschrift 2,359,891.
~owever, the compounds which are novel of our invention having ~:15 the structures:

': /~

~,-20 O

, i"

~25 ~'`.' ' '' ' ~_~0,,.: // ~

,: . O

`1 ~35 ",, ,; ~

,'.

....

.:
: ' . . .

and the mixtures of our invention containing the compounds:

;. 10 ~, O

~,~ 15 O

;and ''. O
,, ~ 20 "s, :~ 25 .. .

. :
- have aroma and flavor intensities and substantivities which are : 30 . signficantly greater than and improved over the compounds of Offenlegungsschrift 2,359,891; and are so unexpectedly advantageous in quality of aroma that these compounds and ,~ mixtures represent an advance in the art over the disclosure of German Offenlegungsschrift 2,359,891. Furthermore, the compounds ~,'...... .. ~ 35 of the instant case which are novel having the structures:
"' ';:- ' , . ..

,~ ; , , .,~ ., , . .

, .
~ ' ' ~
. . .

iXl ~ i ' \~, , ~ ;
.,', h~, .15 . and the mixture of the four compounds having the structures:

~ ~ ~ ~

~ O / "

o ;and ~

., .

''' 11216~
~ -5-::
cannot be prepared by any process but that disclosed in the instant application. In addition, the processes set forth in Offenlegungsschrift 2,359,891 cannot be used to prepare the novel compounds of our invention or for that matter the mixtures .~ 5 of our invention.
q The compounds of our invention and the mixtures of 2,5-;; dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones of - our invention, which 2,5-dialkyl dihydrofuranones and 2,4,5- . trialkyl dihydrofuranones have the structures:
' 10 ~' ~0 '~ O
~ 15 '~ ~0 \``

:,' ' ~
~ ;and . 25 / O

,,,~'' ~0~
,s ., can be prepared according to a process as described in U.S.
"
Patent 3,980,675. However, said process described in U.S. Patent ~. 3,980,675 is limited to the production of 2,5-dimethyl-2-(2H) furanone having the structure:
.: 35 ': ~0 .,,~ ~

i'', O ~/
, ~r, " ' ;~"
~ ~ .

' 11;216~1 and there is no suggestion concerning a method which can be used : to prepare the compounds useful in our invention or the mi~tures of the four compounds of our invention. Thus, whereas the process of 3,980,675 is limited to dimerization of the compound diacetyl followed by hydrolysis in acid media according to the ? reaction sequence:

ii ~ 10 ~ oH ~ ~ o~~
., O

, .
the process of our invention is embodied in the reaction sequence:
~15 2 ~ ~ ~ ~ ~ /+ ~ ~ b~ ~

. ~ -- f.

'~;20 ~ ~ ~ ~ ~ t ~ ~ ~

Accordingly, the process of our invention also represents an advance in the art over the process of U.S. Patent 3,980,675.
,;~, .:- 25 SUMMARY OF THE INVENTION
.:
~ It is a primary object of this invention to provide novel .~; 2,5-dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones having the structures:

'.,,,; \ O /\
: ;35 , .. ~ ~0 O
' ., : .

16~;1 5 ~

' - and mixtures of 2,5-dialkyl dihydrofuranones and 2,4,5-trialkyl dihydrofuranones having the structures:

~ ~-"' ~ 25 :, ; .
; 30 : and the uses thereof in foodstuffs and foodstuff flavorings chewing . gums and toothpastes having sweet, brown sugar, pineapple-like, caramel, buttery, scolded butter~like, dried hazelnut and earthy aromas, and sweet, brown sugar-like, pineapple-like, caramel, buttery, cheese-like, roasted, vanilla-liXe, dried hazelnut and earthy tastes and has for an object the provision of a composition ~ and process for improving the flavor and aroma of foodstuffs.
' ., S~

`:`
DETAILED DE~SCRIPTION OF THE INVENTION

More precisely, the present invention relates to novel compositions and foodstuffs containing dialkyl or trialkyl dihydrofuranones having the structures:
~ ~

''10 O' \
\ - ~ o ~ ~

or mixtures of the four compounds having the structures:
, "
:, ~ /

~O

: 35 ' ~ O ' :
o ~o~

the specific embodiments of which are described hereinafter by way of example and in accordance with which it is now preferred to practice the invention The dialkyl and trialkyl dihydrofuranones and mixtures of our invention are obtained by carrying out processes des-criked in detail in United States Patent 3,980,675 according the the following reaction scheme:
..: .

.
~ r . J~
. j . ~
~ + ~ ~ ~ +

' ~-, wherein 2,3-pentane-dione is first dimerized in the presence ;-25 of an aldol condensation catalyst which can be a base such as ;~ potassium hydroxide, sodium hydroxide, barrium hydroxide, zinc hydroxide, sodium acetate, potassium acetate or zinc acetate at temperatures of between -10C and 50C; preferably at ; temperatures of between 0C and 10C. The resulting dimers .~30 of 2,3-pentane-dione are four in number. These dimers are then '~ hydrolyzed according to the procedure in detail in U.S. Patent 3,980,675 at temperatures in the range of 0C up to 140C in the presence of mineral or organic acids or in the presence of cationic resins or water itself.
- 35 The speed of hydrolysis and the yield of the dialkyl and trialkyl dihydrofuranones are functions of several factors ` which are independent of each other insofar as the temperature, concentrations of acid used to catalyze the hydrolysis, type of 1121~

acid used and duration of ~he reaction are concerned. Variations in the concentration of the starting dimerization product ~ow-ever do not appear to significantly effect the yield of mixture of compounds having the structures:
.~ 5 .,.,,,,, . ~ ,~,0 O
~, ~15 ~ O

~`' ~ O
'' O
~ ~;2 .,', .~ \~ 0 ~ .,~.' ',~f',;
.~ 25 at least within the range of parameters for converting the .~ dimer mixture to the dihydro furanone reaction product mixtur~
in accordance with the preferred embodiments of our process and which are as follows:

". 30 (a) temperature:
between 20C and 120C

(b) concentration of dimerization products : (in grams/100 cc of solution):
between 3 and 11 based on 100~ conversion of the 2,3-pentane-dione in the aldol condensation reaction;

1~ 6~1 tc) acid concentration:
(in grams/lOOcc of solution) between 0.04 and 4.0;

; 5 (d) duration of reaction:
between 1 and 8 hours.
The hydrolysis product can readily be extrac'ed --om the aqueous solution in which it is formed and which o?tionally may be saturated with a mineral salt such as, for exam?le, ;10 sodium chloride or potassium cnloride, bv means or solvents such as diethyl ether, chloroform, 1,2-dichloro ethane or tetrahydrofurane by conventional extracting techn~ues.
~fter the extracting agent is removed bv flash distilla-tion, the resulting crude materlal may be fractionallv distil-led in vacuum to yield a number of fractions each o~~ ~hich fraction contains varying quantities of the com~ounds havinc the structures:
, i ~ 20 ~
~1 ~\ O /\

...
., ~''25 ~ ~ ~ ;and r ~

.

, .

' ~ ` il216~1 ;~
`~ as more particularly described in the following examples.
The resulting mixtures may also be separated by means of `~ various chromotographic techniques such as gas chromotography, or liquid chromotography or high-pressure liquid chromotography whereby the following compounds having the following properties may be obtained:
;~ Compound Structure Name Flavor property o2,4,5-trimethyl-1, A sweet, caramel, 3-dihydro-3- buttery and scorched // \ furanone butter aroma character with a sweet, O caramel, buttery, cheesey roasted and vanilla flavor charac-teristic at 5 ppm in ` water

2,4-dimethyl-5- A dried hazelnut, ethyl-2,3-dihydro- earthy, caramel-like, \ ~ / 3-furanone and buttery aroma with 0 a dried hazelnut, earthy, caramel-like and buttery flavor at 5 ppm in water.
~' 2-ethyl-5-methyl- A buttery, brown sugar-// \ 2,3-dihydro-3- like, pineapple-like furanone caramel-like aroma and `~ O ~ ~ flavor characteristic at 10 ppm in water.
.. O
- ~ 2,5-diethyl-2,3- A brown sugar-like, // \ dihydro-3-furanone caramel and buttery ,f~ ~ aroma and flavor `' ~ O characteristic at 25 ppm.

-One aspect of our invention resides in its commercial importance as illustrated by the fact that it is not necessary to separate out the several di and tri substituted dihydrofuranones produced according to our invention but to leave the resulting distilled mixtures in that state whereby these mixtures may be ~,~ used for their specific flavor nuances in caramel, butterscotch, rum, dairy, vanilla and roasted almond flavored foodstuffs and - confections.
,:, ;.' ' .

` ;`: ` 1121~.r;1 When the dialkyl or trialkyl dihydrofuranone or mixturesof dialkyl and trialkyl dihydrofuranones of our invention are used as food flavor adjuvants or are used to augment or enhance the flavor aroma characteristics of foodstuffs, the nature of the co-ingredients included with said 2,5-dialkyl dihydrofura-nones and/or 2,4,5-trialkyl dihydrofuranones in formulating the product composition will also serve to augment the organo-leptic characteristics of the ultimate foodstuff treated there-with.
As used herein in regard to flavors, the term "augment" in its various forms means "supplying or imparting flavor character or note to otherwise bland, relatively tasteless substances, or augmenting the existing flavor characteristic where a natural flavor is deficient in some regard, or supplementing the exist-ing flavor impression to modify its quality, character or taste.
As used herein in regard to food flavors, the term "enhance"
is used herein to mean the intensification of a flavor or aroma characteristic or note without the modification of the quality thereof. Thus, "enhancement" of a flavor or aroma means that the enhancement agent does not add any additional flavor note.
As used herein, the term "foodstuff" includes both solids and liquids, and ingestible materials or chewable but non-ingestible materials such as chewing gum or chewable medicinal tablets. Such materials usually do, but need not, have nutritional value. Thus, foodstuffs include soups, convenience foods, beverages, gelatin desserts, dairy products, candies, vegetables, cereals, soft drinks, snacks, medicinal products such as cough mixtures and cough drops and the like.
Substances suitable for use herein as co-ingredients or flavoring adjuvants are well known in the art for such use, being extensively described in relevant literature. Apart from the requirements that any such materials be organoleptically compatible with the dialkyl and trialkyl substituted dihydro-furanones and mixtures thereof of our invention, non-reactive with the dialkyl and trialkyl dihydrofuranones and mixtures thereof of our invention and "ingestibly" acceptable and thus non-toxic or otherwise non-deleterious, nothing particularly critical resides in the selection thereof. Accordingly, such materials ~, ~

:

`~ ` 112::~6~51 : -13-which in general may be charac~erized as flavor~ng ~djuv~nts or .; vehicles comprise broadly stabilizers, thickeners, surface active agents, conditioners, other flavorants and flavor intensiriers.
Stabilizer compoun~s include preservatives, e g. sodium 1 5 chloride; antioxidants, e.g., calcium and sodium ascorbate, ; ascorbic acid, butylated hydroxyanisole (mixture of 2- and ,-tertiarv-butyl-4-hydroxyanisole), butylated hydroxytoluene (2,~-di-tertiary-butyl-4-methyl phenol), propyl gallate and tne liXe and sequestrants, e.g., citric acid.
Thickener compounds include carriers, binders, protective `-~ colloids, suspending agents, emulsifiers and the like, e.g., agar agar, carrageenan; cellulose and cellulose derivatives such as carboxymethyl cellulose and methyl cellulose; natural and synthetic gums such as gum arabic, gum tragacanth; gelatin, proteinaceous materials, lipids; carbohydrates; starches, pectins and emulsifiers, e.g., mono- and diglycerides of fatty acids, skim milk powder, hexoses, pentoses, disaccharides, e.g., sucrose corn syrup and the like.
Surface active agents include emulsifying agents, e.g., ' ~0 fatty acids such as capric acid, caprylic acid, palmitic acid, myristic acid and the like, mono- and diglycerides of fatty acids, lecithin, defoaming and flavor-dispersing agents such as sorbitan monostearate, potassium stearate, hydrogenated tallow alcohol and the like.
Conditioners include compounds such as bleaching and ;; maturing agents, e.g., benzoyl peroxide, calcium peroxide, hydrogen peroxide and the like; starch modifiers such as peracetic acid, sodium chloride, sodium hypochloride, propylene .~ oxide, succinic anhydride and the like, buffers and neutralizing agents, e.g., sodium acetate, ammonium bicarbonate, ammonium phosphate, citric acid, lactic acid, vinegar and the like;
colorants, e.g., carminic acid, cochineal, tumeric, curcumin ; and the like; firming agents such as aluminum sodium sulfate, calcium chloride and calcium gluconate, texturizers, anti-caking agents, e.g., aluminum calcium sulfate and tribasic calcium phosphate; enzymes, e.g. mylase; yeast foods, e.g., calcium lactate and calcium sulfate; nutrient supplements, e.g., iron salts such as ferric ~hos~late, Eerrous glucon~te -~n~ e Ll'-e, riboflavin, vitamins, zinc sources such as zinc chloride, ~inc sulfate and the like.
Other flavorants ancl flavor intensifiers include organic acids, e.g., fatty saturated acids, unsaturated aci-ls, and amino acids; alcohols, e.g., primarv and secondarv alcohols; esters, carbonyl compounds including aldehvdes and ketones as well as lactones; cyclic organic materials including benzene derivatives;
isocyclics; heterocyclics such as furans, particularly 2,5-dimethyl-3-acetal furan and 2-methyl-~,3-dihydrofuran-3-one, pyridines, pyrazines (particularly monoal~yl, dialkyl, trialkyl and tetraalXyl substituted p~ra~ines) and the like, sulfur-containing materials including thiazoles, disulfides, thiols, sulfides, aldehydes, ( or example, 3-phenyl-4-pentenal, 3-phenyl-

3-pentenal, 3-phenyl-2-pentenal, 2-phenyl-2-pentenal and 2-phenyl-3-methyl-2-butenal); disulfides and the like; other flavor potentiators such as monosodium glutamate; guanylates, inosinates, natural and synthetic flavorants such as vanillin, ethyl vanillin, diacetvl, phenethyl-2-furoate, maltol, ethvl maltol, natural gums and the like; spices, herbs, essential oils and extractives including "bitterness pri~ciples" such as theobromin, caffein, naringin and other suitable materials creating a bitter effect.
The specific flavoring adjuvant selected for use may be either solid or liquid depending upon the desired physical form of the ultimate product, i.e., foodstuff, whether simulated or natural, and should, in any event, be capable of providing an environment in which the 2,5-dialkyl dihydrofuranones and/or 2,4,5-trialkyl dihydrofuranones can be dispersed or admixed to provide a homogeneous medium. In addition, selection of one or more flavoring adjuvants as well as the quantities thereof will depend upon the precise organoleptic character desired in the finished product. Thus, in the case of flavoring compositions, ingredient selection will vary in accordance with the foodstuff to which the flavor and aroma are to be imuarted. In contra-distinction, in the preparation of solid products, e.g,simulated foodstuffs, ingredients capable of providing normally solid compositions should be selected such as various cellulose derivatives.

Sl , 5 .
~ s will be appreciated by those skille~ in the art, ~.e amount of 2,5-dialkyl dihydrofuranones and/or 2,4,5-trial~yl dihydrofuranones emploved in a particular instance can varv ` over a relatively wide range whereby to its desired organo-leptic effects havins reference to the nature of the product are achieved. All parts and percentages given herein are by weight unless otherwise specified. Thus, correspondingly ` greater amounts would be necessary in those instances wherein the ultimate food composition to be flavored is relatively bland to the taste, whereas relatively minor quantities may - suffice for purposes of enhancing the composition merely de-; ficient in natural flavor or aroma. Thus, the primary require-ment is that the amount selected to be effective, i.e., suffi-cient to alter the organoleptic characteristics of the parent composition, whether foodstuff per se or flavoring composition.
Thus, the use of insufficient quantities of 2,5-dialkyl dihyro-furanones and/or 2,4,5-trialkyl dihydrofuranones will, of course, substantially vitiate any possibility of obtaining the desired results while excess quantities prove needlessly costly ; 20 and in extreme cases, m-ày disrupt the flavor-aroma balance, thus proving self-defeating. Accordingly, the terminology "effective amount" and "sufficient amount" is to be accorded `~ a si~nificance in the context o the present invention consis--tent with the obtention of desired flavoring effects.
Thus, and with respect to ultimate food compositions, it is found that quantities ~f 2,5-dialkyl dihydrofuranones and/or 2,4,5-trialkyl dihydrofuranones ranging from a small but effective amount, e.g., 0.1 part per million up to about 50 parts per million by weight based on total composition are suitable when used alone without other cyclic di-ketones. Further, when used `~ with such cyclic di-ketones as maltol, cyclotene, and 2,5-dimethyl-4-hydroxy-3(2H)furanone, the concentration of 2,5-dialkyl dihydrofuranones and/or 2,4,5-trialkyl dihydrofuranones can be as low as 0.05 part per million. Concentrations in excess of the maximum quantities stated are not normally recommended since they fail to provide commensurate enhancement of organo-leptic properties. In those instances wherein the 2,5-dialkyl ~` dihydrofuranones and/or 2,4,5-trialkyl dihydrofuranones is added to the foodstuff as an intesral component of a flavoring comp-osition, it is, of course, essential that the total quantity of :';., ,"
. ' .

li2~6Sl flavoring composltion employed be suf~icient to ~iel-~ an ef~ective 2 r 5-dialkyl dihydrofuranone and/or 2,4,5-trialkyl dihvdroruranone concentration in the foodstuf~ product.
Food flavoring compositions prepared in accordance with the present invention preferably contain the 2,5-dialkyl dihYdrofuranones and/or trialkyl dihydrofuranones in corcen-trations ranging from about 0.1~ up to about 10% by weight ;- based on the total weight of said flavoring composition when the 2,5-dialkyl dihydrofuranone and/or 2,4,5-trialkyl dihydro-furanone is used without other cyclic di-ketones.
The compositions described herein can be pre~ared according to conventional techniques well known as tvpified by cake batters, and "fruit" juices can be formulated by merely admixing the involved ingredients within the proportions stated in a ; 15 suitable blender to obtain the desired consistency, homogeneity of dispersion, etc. Alternatively, flavoring compositions in the form of particulate solids can be conveniently prepared by admixing the 2,5-dialkyl dihydrofuranones and~or 2,4,5-trialkyl ~?~ dihydrofuranones with, for example, gum arabic, gum tragacanth, 2~ carrageenan and the like, and thereafter, spray drying the resultant mixture whereby to obtain the particular solid product.
Pre-prepared flavor mixes in powder form, e.g. a vanilla powder ~ or "maple sugar" flavored powder obtained by mixing the dried ; solid components, e.g., starch, sugar and the like and 2,5-dialkyl dihydrofuranones and/or 2,4,5-trialkyl dihydrofura-nones, in a dry blender until the requisite degree of uniformity is achieved.
It is presently preferred to combine with the 2,5-dialkvl dihydrofuranones and~or 2,4,5-trialkyl dihydrofuranones the following adjuvants.
Eugenol Guaiacol Vanillin Sucrose Heliotropin Ethyl Vanillin ; Maltol , '., , :- .

Ethyl Maltol Cyclotene Ethyl Cyclotene Methyl Cyclopentenolone Butyrate 2,5-Dimethvl-4-HydrOxv-3(2H)-Furanone Isovaleraldehyde 5-~ethyl Furfural Rum Ether Pyruvic acid and Ethyl Butyrate The following examples are given to illustrate embodiments of the invention as it is presently preferred to practice it.
It will be understood that these examples are illustrative and -15 that the invention i9 not to be considered as restricted thereto except as indicated in the appended claims.

65~

EXAMPLE I

.
PREPARATION OF MIXTURE OF 2,4,5-TRIMETHYL-2,3-DIHYDRO-3-FURANONE; 2,4-DIMETHYL-5-ETHYL-2,3-DIHYDRO-3-FURANONE;
2-ETHYL-5-METHYL-2-3-DIHYDRO-3-FURANONE; and 2,5-DIMETHYL-2,3-DIHYDRO-3-FURANONE
Reaction:

2 ~ t ~ ; ~ +

, ~ - -- ~
~ _ _ _ _ ~+~X+~+ <~, Part A. Preparation of compounds:

~ ;
'-' ' ~,~0 ,'~, O
,,. //o ' ~ ~ ; and .,~ O

~. ~0~

',;-112:16~i~

Into a 2 liter reaction flask equipped with mechanical stirrer, condenser, additon funnel and thermometer is placed 2.5 moles (250 grams) of 2,3 pentane dione. Over a period of 1.5 hour at a temperature range of from -2C up to +6C, 350 ml of 20% KOH solution (acqueous) is added to the reaction mass with stirring. The reaction mass pH is then adjusted to 7 using 50%
hydrochloric acid. 40 ml concentrated hydrochloric acid is then added to the reaction mass which is then heated using steam to 95C and maintained at 95% over a period of 6.5 hours. The pH of the reaction mass is then adjusted to 7 using a 25% acqueous solution of sodium hydroxide. The reaction mass is saturated , with sodium chloride then extracted with one portion of 500 ml anhydrous diethyl ether and two portions of 250 ml each of anhydrous diethyl ether. The diethyl ether extracts are combined ' and washed to two 75 ml portions of saturated sodium bicarbonate followed by three 150 ml portions of saturated sodium chloride.
The resulting extract is then concentrated yielding 262 grams of crude containing 55% solvent. The crude is then rush over-distilled in a 500 ml distillation flask into 12 fractions.
Hal of the fractions 3-8 are combined and distilled on a spinning band column yielding 22 fractions. The fractional distillation data is as follows:

; No. Vapor Liquid Vac.Wt. of Temp.(C) Temp.(C) mm. HgFraction g.

1 23 - 75 40 - 104 40 - 3810.2 2 87 120 38 14.5 -; 3 96 130 38 11.1

4 98 135 38 11.0 101 144 38 11.4 6 103 151 38 8.6 7 108 159 38 10.9 8 114 164 37 9.3 9 130 166 28 14.6 128 172 18 17.6 11 160 190 18 19.4 12 160 198 16 24.6 .

., llZ~

~o The spinning band distillation data is as ~ollows:
:
~o, Vapor Liquid Vac. Reflux TemP.(C) Tem~.(C) mm.H~ Ratio 1 26 55-98 65 1:1 - 2 56 105 32 1:1 . 3 59 104 32 1:1 . ~ 4 59 106 32 1:10 ,~, 10 5 S9 106 32 1:10 6 59 108 32 1:15 ', 7 59 109 32 1:15 ~; 8 62 110 32 1:15 ' 9 74 111 32 1:15 76 114 32 1:15 11 76 116 32 1:15 12 80 116 32 1:15 I - 13 80 118 32 1:15 .~ 14 80 121 32 1:~5 84 122 30 1:15 , 16 93 126 30 1:15 . ~ 17 95 127 30 1:15 - - 18 86 146 32 1:15 - . 19 78 152 24 1:15 ~'i. 25 20 76 142 10 1:15 21 76 172 8 1:15 22 38 176 1 1:15 .
" .
Fractions 3-8 from the rushover distillation yield contain ' the following compounds:
,',',.
~i 29% of compound having the structure:
,~ 15 _~ ~

,;.
. ' . "'' , ~ ,, . . .
.
....

l~ of ^em~oun~ llaving the structure:

'. ~0 ~'; '.
.~ 17~ of com~ound having the st_ucture:
` ` 10 ~2 ~ \~o~~
~15 I 12% of compound having the structure:
.
O
. 20 ~O
.,' : 25 The spinning band distillation yields the following:

~. Fraction 7: g8% pure compound having the structure:
'''', . _~0 . 30 ~ ~ ~

~::
.~
Fraction 10: 90% pure compound having the structure:

;i 35 :, ~5 ;,.", O \~

,'~

., .
'' . .

Fraction l.S: 96% pure compound having the structure:
,', ~
''' ~, Fraction 19: 94% pure compound having the structure:
,\~<0 ~0 Figure 2 is the NMR spectrum for 2,4,5-trimethyl-2,3-dihydro-3-furanone produced according to Example I.

;,. Figure 3 is the NMR spectrum for 2,4-dimethyl-5-ethyl-2,3-dihydro-3-furanone produced according to Example I.

Figure 4 is the NMR spectrum for 2-ethyl-5-methyl-2,3-, dihydro-3-furanone produced according to Example I.
',;, . Figure 5 is the NMR spectrum for 2,5-diethyl-2,3-dihydro-. 3-furanone produced according to Example I.

Figure 6 is the infrared spectrum for 2,4,5-trimethyl-2, 3-dihydro-3-furanone produced according to Example I.

Figure 7 is the infrared spectrum for 2,4-dimethyl-5-ethyl-2,3-dihydro-3-furanone produced according to Example I.

. Figure 8 is the infrared spectrum for 2-ethyl-5-methyl-2, . 3-dihydro-3-furanone produced according to Example I.

Figure 9 is the infrared spectrum for 2,5-diethyl-2,3-dihydro-3-furanone produced according to Example I.
:i . ~

Part B: Commercial preparation of mixture of compounds having the structures:

~0 \0/

:` ~ Q
~ V~ /~ ;
O
, O

; and ~0 ''''; ~0~
.~, , Into a 3 liter reaction flask equipped with mechanical stirrer, condenser, addition funnel and thermometer are placed 500 grams of 2,3-pentane dione. The reaction mass temperature is kept at approximately -5C using an isopropanol/dry ice bath.
100 ml of a 10% aqueous KOH solution is then added dropwise over a period of 30 minutes while maintaining the reaction mass temperature at between -5C and +6C. 480 ml of a 20% aqueous KOH solution is then added dropwise over 1~ hours while keeping mass temperature at -5C - +6C. The pH of the resulting slurry is then adjusted to 7 using 80 ml of a 50% H2SO4 solution (aqueous) followed by 80 ml concentrated HCl addition. The reaction mass is ,, 1121~

~'`
then steam heated (at 95C over a period of 7 hours). The reaction mass is then cooled and the pH of the slurry is adjusted to 7 using 125 ml of 25% NaOH followed by adding 144 grams of sodium chloride. The reaction mass is then extracted with anhydrous diethyl ether t750 ml x 1; 500 ml x 2;
and 250 ml x 1). The diethyl ether extracts are combined and washed twice with saturated sodium bicarbonate (250 ml, 200 ml -~and 100 ml) and 10% sodium carbonate ~450 ml x 2). The ether extract is then washed with saturated sodium chloride (200 ml x 3) and dried over anhydrous sodium sulfate. The concentrated crude obtained (419 grams with solvent) or 326 grams without solvent is then analyzed: GC analysis indicates that this material contains 15~ compound having the structure:
: /~o ,,;~i, '~s.",: ~
'-'' O
: ¢~
8.5~ compound having the structure:
'.',' ,~0 ~. /~0 /\/
12.5 compound having the structure:

; and ", ~
; 7.8% compound having the structure:
,, ,,, "

, llZ~6Sl Another 500 grams o~ 2,3 propane dione is reacted with KOH
in a manner similar to that set forth above as follows: To 500 grams of 2,3 pentane dione 100 ml 10% aqueous KOH is added ` keeping the reaction temperature at -3C - +7C. 450 ml 20%
aqueous KOH is added over a period of 1.5 hours at -3C - +7C.
The pH is adjusted to 7 using 80 ml 50% H to a sulfur followed by 80 ml concentrated hydrochloric acid. The reaction mass is steam heated at 95C for 7 hours. The slurry is admixed with 75 grams of sodium chloride and extracted with diethyl ether (500 ml x 2; 300 ml x 1~. The ether extract is washed with ;~ saturated sodium chloride (250 ml x 2) and then washed with 10% Na2CO3 (200 ml x 2); 150 ml x 1). The ether extract is then washed again with saturated sodium chloride (200 ml x 2, ~;~ 150 ml x l) and dried over anhydrous sodium sulfate. Theconcentrate obtained weighs 327 grams and is analyzed as follows:

20.3% compound having the structure:
~:;
,:,.,: ~0 .:' ~O~
,: .`~ ` .
. ~
~ 9.2% compound having the structure:
~"
16.7% compound having the structure:
\~0 ,.,: // \
'`' ~o 7.8% compound having the structure:
' :
~<0 \0 ' . .

~ ~ .

`` llZ~6~
., The combined crudes have a total weight of 800 grams. The i: combined crudes are then rushed over distilled yielding 13 ` fractions as follows:
':' ~f 5 No. Vapor Liquid Vac Weight of '~ Temp.(C) Temp.(C) mm.Hg Fraction g.

~ 1 30-50 55-80 110 5.0 '`, 2 50-35 80-90 110-40 10.3 3 75 127 38 10.3 4 94 129 38 6.0 97 133 38 15.0 ~ 6 99 147 38 76.0 ''` 7 107 165 36 60.0 ~' 15 8 121 168 25 32.0 9 124 170 18 42.0 130 178 14 23,1 11 134 180 11 29.6 12 137 189 10 25.7 13 140 193 5 27.3 Combined fractions 6, 7 and 8 from the rushover are then redistilled yielding the following reactions:
No. Vapor Liquid Vac. RefluxWt. of Temp.(C) Temp.(C) mm. RatioFraction g.

1 21-48 70-88 13 4:1 6.6 2 73 88 13 4:1 4.2 3 74 88 14 4:1 4.4 4 74 89 13 4:1 2.4 76 89 13 4:1 4.5 6 76 89 13 4:1 3.8 7 76 89 13 4:1 3.4 8 76 89 13 4:1 4.2 9 75 89 13 9:1 1.6 . .
' ,.. . ~

: .

" il~l~;~i No. Vapor Liquid Vac. Reflux Wt. of Temp.( C~ Temp.( C) mm. Ratio Fraction g.
~ . .
13 9:1 2.5 11 75 90 13 9:1 2.3 . 12 75 90 13 9:1 2.8 13 76 90 13 9:1 3.4 14 78 92 13 3:1 11.7 , 15 79 92 13 3:1 10.3 16 80 93 13 3:1 9.0 17 82 96 13 3:1 13.1 18 82 96 13 3:1 10.6 ' 19 82 98 13 3:1 15.8 84 112 13 3:1 11.1 21 88 145 13 3:1 11.8 22 83 250 3 3:1 12.0 Fractions 6, 7 and 8, prior to distillation contain 37%
compound having the structure:

O

15.9% of compound having the structure:
~ ~

28.4% of compound having the structure:
:

~ O

ll.~ Sl ~ 28-, 1 .
and 15.3% of compound having the structure:
."~ ~

, ,.
Figure 1 is a GC profile of the reaction product of Example 1 which contains a mixture of compounds having the structures:

<~

~ O

~ ; and ~ O
.,,i ~0~

' 35 , 11216~1 : `
:, :`

having the names, respectively, 2,4,5-trimethyl-2,3-dihydro-3-furanone;2,4-dimethyl-5-ethyl-2,3-dihydro-3-furanone; 2-ethyl-

5-methyl-2,3-dihydro-3-furanone; 2,5-diethyl-2,3-dihydro-3-furanone.
The final distillation is carried out on a Goodloe column - from which fractions 6-21 were combined and submitted for evaluation. This material has a sweet, caramel, diacetyl-like, buttery aroma characteristic with sweet, caramel, diacetyl-like, buttery and vanillin flavor characteristics. It is useful in caramel, butterscotch, rum, dairy, vanillia and roasted almond flavors. The level of useage may vary from 0.5 ppm up to 100 ppm with a preferred level of useage at 1-5 ppm.
:' EXAMPLE II
BASIC CARAMEL FLAVOR FORMULATION

The following caramel flavor formulation is prepared:

IngredientsParts by Weight Palatone 3 Heliotropine 2 Cyclotene 2 Vanillin 2 Isovaleraldehyde 5-Methyl Furfural 2 Rum Ether 15 Pyruvic acid 5 Ethyl Butyrate 10 Propylene glycol158 :
This basic caramel flavor is divided into two parts. To the first part, 5% by weight of the bulked fractions 3-8 resulting from the rushover distillation of E~ample I, Part A, is added. To the second part nothing is added. Both flavors are tested at the rate of 20 ppm in water by a bench panel of three flavor experts. All three members of the bench panel 1~16~1 : '~
- :.
state that the formulation containing said mixture prepared according to Example I, Part B has a more characteristic caramel, burnt sugar aroma and taste. In addition, there is a buttery mouthfeel in the flavor formulation containing the ~- 5 mixture prepared according to Example I, Part B. Therefore the flavor containing the mixture prepared according to Example 1, Part B is unanimously preferred as having a better caramel character.
.
E~AMPLE III
ISOLATION OF 2,4,5-TRIMETHYL-3(2H)FURANONE FROM BACON FLAVOR

500 pounds of Oscar MayerTM bacon was firstly ground to 3/16" mesh and each batch (100 pounds) was cooked in steam jacked kettle from 50F to 350F over a period of one hour. Slurry obtained from 5 batches was about 300 pounds, about 200 pounds of water was lost during the process. The slurry was subjected to vacuum steam - distillation in ten charges and each charge is distilled in two passes. The apparatus is set forth in Figure 10. The resulting distillate was saturated with NaCl and subjected to continuous extraction and concentrated to 1 liter.
A small portion is taken to estimate the total volatile weight which is approximately 3 grams. The total volatiles ' are chemically separated using the separation scheme as set forth in Figure 11. 400 mg of phenolic fraction obtained is fractionated on a silicon dioxide column (10% deactivated , silica, 14 grams, column volume equals 30ml/250mm x 12mm) using isopentane and then varying mixtures (1% - 100%) of diethyl ether in isopentane.
The fraction containing the 2,4,5-trimethyl-2(2H)furanone is subjected to GLC analysis (conditions: stainless steel ; carbowax 20M column, 1/8 inch x 10ft., 60-220C at 4C/minute).
The GLC chromatogram is set forth in Figure 12. The 2,4,5-trimethyl-3(2H)furanone synthesized according to Example I, Part A has a GLC profile as set forth in Figure 13. The GLC
profile retention time for said furanone in Figure 13 is identical to the GLC profile retention time of the furanone llæl~.sl -isolated from fried bacon flavor. The IR spectrum for the isolated furanone is set forth in Figure 14. The NMR
spectrum for the isolated furanone is set forth in Figure 15.
The mass spectrum for the isolated furanone is set forth in Figure 16.

EXAMPLE IV

The following ingredients are homogeneously admixed at 25C:

INGREDIENTS PARTS
.
Vegetable shortening622.7 Salt 321.7 Glutamic Acid 5.1 L-Cysteine hydrochloride 10.3 Glycine 5.1 ~3 -Alanine 1.3 Taurine 20.0 Mixture of di-sodium inosi-- nate and di-sodium gurany-late 3.3 The mixture is heated at 300F for 30 seconds. After cooling to 100F, 0.05 parts of a mixture of dialkyl and tri-alkyl dihydro furanones having the structures:
;

O

O
~ ~ ;

: ~5 ~ \
/, ~ ,/ \ / ;and ~,,0 - 0 ~

prepared according to Example I. The resulting mixture has : an excellent bacon aroma and taste.

EXAMPLE V

Cysteine hydrochloride in the amount of 8.8g is refluxed .at 215F under atmospheric pressure for four hours with a mixture of 309g of hydrolyzed vegetahle protein and 674g of ,water. Subsequent to the reflux, the mixture is cooled and 0.05g of a mixture of dialkyl and trialkyl dihydro furanones having the structures:
~ O

, , \0 /

~0 ~0/~

-3~-/~ \

o h~
/\ O ~

prepared according to Example I is added and intimately admixed with the composition. The mixture has an excellent fried bacon flavor of high tensity.

.
EXAMPLE VI

To composition prepared in Example IV is diss-olved i~ pro~ylene Iglycol to provide a 0.1% solution. This solution in the amount of 0.966g is added to 7.3g of a soup base consisting of:

,j ~, INGREDIENTS PARTS
. .
' Fine ground sodium chloride 35.62 Hydrolyzed vegetable protein 27.40 Monosodium glutamate17~81 , Sucrose 10.96 ,~ Beef Fat 5.48 Sethness caramel color (powder B&C) 2.73 The resulting mixture is added to 12 ounces of boiling water to obtain a soup having an excellent bacon flavor.

-3~-~X~MPLE VII

The composition prepared in ~xam~le V is dissol~ed in ~ropvlene glycol to provide a 0.1n~ solution. This solution in the amount of 0.96~g i5 added to 7.3g of a soup ~ase con-sisting of:

INGRED-IENTS PARTS

Fine ground sodium chloride 35.62 Hydrolyzed veg~table protein (Maagi 4sE~ 27.40 Monosodium glutamate 17.81 Sucrose 10.96 Beef Fat 5~8 Caramel color, bakers and ~-15 confectioner's powder grade 2.73 The resulting mixture is added to 12 ounces of boiling water to obtain a soup having an excellent bacon flavor.

, 20 EXAMPLE VIII

. - One-half gram of the soup base mixture of Example VI is : emulsified in a solution containing 100g grm arabic and 300g :25 water~ The emulsion is spray-dried with a Bowen Lab Model ; Drier Utilizing 250 cfm of air with an inlet temperature of 500F, an outlet temperature of 200F, and a wheel speed of 50,000 rpm, Twelve grams of the spray-dried material is,mixed with ':30 29.2g of the soup base set forth in Example VI. The resulting mixture is then added to 12 ounces of boiling water and an ~r excellent bacon flavored soup is obtained.
.:
, ' ~ d'e ~1a~

:

112~

E~AMPLE I "
BAS IC BACON Fl,AV()R

.
The following basic bacon flavor is produced:

ING~EDIENTS PARTS
__ - Vanillin 2.0 . Eugenol 1.0 Guaiacol 0.2 Para-Vinvl Guaiacol 0.2 Cyclotene 1.0 ~: Trimethyl Pyrazine 0.4 Acetyl Pyridine 0.1 :` 15 2,4-decadienal, 1~ 0.1 Furfural 0.4 . Benzaldehyde 1.0 Isovaleraldehyde 1.0 . Methyl Thiazole Alcohol 7.6 ~20 Foodgrade Ethyl Alcohol 185.0 Hickory Smoke Flavor, natural ~Fleischmann Co., 800.0 - New York, a Div. of Standard Brands) : 25 ` This basic bacon flavor is divided into two portions.
~The first portion at the rate of 0.02ppm, the mixture or ~ ~ :dialkyl and trialkyl dihydro furanones having the stuctures:

:'` ~0 .'~ 30 ~/
",:. \O /~
,,.' `:

'~'35 ~ :

~' ' ' ' ~;' .',,.,' ~

` ` il216~1 -O ,~ ;and , h~
: /\ ~
. lo 5 :
.~r produced according to Example I. To the second portion of the : basic bacon flavor nothing is added. The two flavors with and without the dialkyl and trialkyl dihydro furanone mixtures are ~^mpared at the rates of lOOppm in water and evaluated by an expert flavorist panel. The flavor containing ths dialkyl and trialkyl dihydro furanone mixture has a crisp bacon aroma and taste and additional pork fat notes not present in the basic . bacon flavor without the dialkyl and trialkyl dihydro furanone ~ 20 :mixture. Therefore the flavor with the dialkyl and trialkyl : dihydro furanone mixture is unanimously preferred.
~,. . .
;

~25 ... .

., ","

, ., .

.:
.: .
, :
,.' .

-,7-3RIEF ~ESCRIPTIO~I ~F THE nR~IMGs Fiaure 1 is the gas chromotogra?h (GC) ~rofile -sr th~
mixture of compounds each of ~hich has the struct~lre:

' ~,0 y \ (2,4"-trimethvl-~,3-~ \ ,~` dihydro-3-furanGne);

~0 (2,4-dimethyl-5-ethvl-2,3-~ ~ dihydro-3-furanone);
:
; 20 O

- ~ (2-ethyl-5-methyl-2,3-~ dihydro-3-furanone~;
~ 25 .^, ~
,', ~/ ' i 30 ~ ~ (2,5-diethyl-2,3-dihydro-,~ 3-furanone~

produced according to Example I, and containing 37Q compound having the structure:
',': O
(2,4,5-tr~methvl-2,3-. ~ , ~ dihydro-3-furanone);
v "

1~'3~8~6~1 15~ or compound havin~ the struct-~r~:

` 5 ~ ~
''~ ~\ ~/ (''-eth~ltl-i-rnethyl-2, '-O dihydro-3-furanone);

;lO 27~ of compound having the structure:

~,~0 ~: ~ \ (2,4-dimethvl-5-ethyl-~ 2,3-dihydro-3-furanone);
: and 15~ of compound having the structure:

'20 (2,5-diethyl-2 r 3-dihydro-; O ~ 3-furanone) . 25 ~'' Figure 2 is the NMR spectrum for the compound having the ; ~ structure:

' ~ O

''~ \ O ~'~" (2,4,5-trimethyl-2,3-dihydro-3-furanone) produced according to Example I.

:, ',.:' .
.~"

; : .
, -_3a_ Figure 3 is the NMP~ sp~ctrllm ~.or the com~4~lnd naving th^
structur~:

i ,,~.
` ~ Y / ~ (2,4-dimethyl-5-ethyl-2,3-O dihvdro-3-furanone) , .0 produced according to Example I.
:' Fiqure 4 is the NMR spectrum for the compound having the structure:
~ ,~0 .:'.' ~/ \
,~ " ~ \ ~ (2-ethyl-5-methyl-2,3-. O dihvdro-3-furanone) ; 20 produced according to Example I.

.
Figure 5 is the NMR spectrum for the compound having the ~;. .structure:
, O
. ~ (2,5-diethyl-2,3-dihydro-, ,, ~ ~ > 3-furanone) ... ;.
produced according to Example I.
.

Figure 6 is the infrared spectrum for the compound having ~ the structure:
~35 ~ _ , ~ ~ (2,4,5-trimethyl-2,3-~~~` o ' dihvdro-3-furanone) produced according to Exampl~ I.
.c~, -'.
, ,:

'' ~ . .

.

1~216S:~
o--~ Figure 7 is the infrared s~ectrum for the comnound ha~in~
the structure:
:, ~ ~ (2,4-dimeth~ -eth~
~ ~ 2,3-dihydro-3-furanor.e) produced according to Example I.
Fiqure 8 is the infrared spectrum for the compound having the structure:
'. ,~
~15 ~ \ (2-ethyl-S-methyl-2,3--~. ~ dihydro-3-furanone) ;
produced according to Example I.
: 20 Figure 9 is the infrared spectrum for the compound having ~ ,the structure:
,~ ; O
.~25 / r ~ ~2,5-diethyl-2,3-~ o dihydro-3-furanone) ~- , .
produced according to Example I.
. 30 . Figure 10 sets forth the vacuum steam distillation apparatus used in the isolation of 2,4,5-trimethyl-3(2H)-furanone from bacon flavor of Example III.
. ;
Figure 11 is an illustration of the chemical separation . scheme of Example III.

, .
'; .
':, ; ,, '."

....
' '~
' Fiqure 12 is the GLC ~rofile for the chromotosr~?nic fraction containing 2,~,5-trimethvl-3(2~ furanone produced in Example III.
:' 5Figure 13 is the GLC profile for 2,~ trimethvl-3(2 furanone produced according to Example III.

Fiqure 14 is the infrared s~ectrum for the isolated 2,4,5-trimethyl-3(2H)-furanone of Example III.
. o Figure 15 is the NMR spectrum for the isolated 2,4,5-:~ trimethyl-3(2H)-furanone produced according to Example III.

Figure 16 is the mass spectrum for the isolated 2,4,5-~A '.5 ~rimethyl-3(2H)-furanone produced according to Example III.
,.

., .

~ ,0 :' :
" " '''' . .
:, - , .

!5 .~,: :, . .

.
',~0 :' "; ~

,: .

.

. .~ i ,, ,: , ., :.
.'' .,~

: ~

Claims

The embodiments of the invention in which exclusive property or privilege is claimed are defined as follows:

Claim 1: A process for augmenting or enhancing the taste or aroma of a caramel, butterscotch, rum, dairy, vanilla or roasted almond-flavored foodstuff comprising the step of adding to said foodstuff from about 0.1 ppm up to about 50 ppm by weight of said foodstuff of a mixture of dialkyl and trialkyl dihydrofuranones having the structures:
;
;
; and wherein the weight percentage ranges of said dihydrofuranones in said mixture is from about 10% up to about 40% by weight of the compound having the structure:

from about 5% up to abbut 20% of the compound having the structure:

.

from about 10% up to about 30% of the compound having the structure:

and from about 5% up to about 20% of the compound having the structure:

.

Claim 2: A flavor augmenting or enhancing composition for augmenting or enhancing the caramel, butterscotch, rum, dairy, vanilla or roasted almond flavor of foodstuffs comprising from about 0.1% up to 15% by weight based on the total weight of flavoring composition of a mixture of dialkyl and trialkyl dihydrofuranones having the structures:

;
;

; and and the remainder of said composition being at least one adjuvant selected from the group consisting of:
Eugenol Guaiacol Vanillin Sucrose Heliotropin Ethyl Vanillin Maltol Ethyl Maltol Cyclotene Ethyl Cyclotene Methyl Cyclopentenolone Butyrate 2,5-Dimethyl-4-Hydroxy-3(2H)-Furanone Isovaleraldehyde 5-Methyl Furfural Rum Ether Pyruvic acid; and Ethyl Butyrate wherein the weight percentage ranges of said dihydrofuranones in said mixture is from about 10% up to about 40% by weight of the compound having the structure:

IMG>

from about 5% up to about 20% of the compound having the structure:

from about 10% up to about 30% of the compound having the structure:

and from about 5% up to about 20% of the compound having the structure: