CA2020564A1 - Peanut butter with improved oxidative stability - Google Patents

Abstract

PEANUT BUTTER WITH IMPROVED OXIDATIVE STABILITY
Abstract of the Disclosure The invention is a peanut butter comprising a dispersion of finely divided peanut particles in a continuous oil phase.
The oil phase comprises peanut oil derived from peanuts in which the naturally occurring oil has a fatty acid composition such that the oleic:linoleic acid ratio is between about 6:1 and about 40:1. The peanut butter has improved resistance to oxidation and staling.

Description

20205~

PEANUT BUTTER WITH IMPROVED OXIDATIVE STABILITY

Technical Field This invention relates to peanut butters. More partic-ularly, the invent~on relates to a novel peanut butter that has greatly improved resistance to oxidation and staling.
Background of the Invention It is known that peanut butter consists of a mixture of solid nut particles and liquid peanut oil which is generally made by roa~ting and blanching raw peanut kernels and then grinding them. The grinding operation breaks the cellular structure of the peanut kernels and liberates oil in which the comminuted nut particles are suspended to form a product having a pasty and spreadable consistency. This product is generally called the peanut "pasten. A stabilizer is usually added to the peanut paste in making peanut butter to prevent oil separation, and optionally other ingredients are added such as an emulsifier, a sweetener and salt.
Peanut butter also contains a certain amount of oxygen in addition to the nut particles, peanut oil and other ingredients. Oxygen is present in adsorbed and entrained form in the peanuts prior to grtnding, and solid sweeteners and salt also contain entrained oxygen. Further, atmospheric oxygen becomes dissolvet in the peanut butter during the - grinding and mixing steps, and it is present in the headspace _ of the peanut butter container.
; 25 The presence of this o~xygen reduces the shelf life of peanut butter. Oxygen reacts with (oxidizes) the peanut oil, and thus causes the peanut butter to develop rancidity and a stale taste after storage.

2~29~64 There have been numerous attempts to develop peanut butters that have increased stability through a reduction of this oxidation problem. For example, U.S. Patent 1,445,174 to Rosenfield, issued February 13, 1923 and reissued as no.
15,918 on September 23, 1924, discloses a process for reducing peanut butter rancidity in which the peanuts are ground, then the peanut oil is extracted, hydrogenated and reincorporated into the peanut butter.
U.S. Patent 2,198,219 to Musher, issued April 23, 1940, lQ discloses a process for stabilizing peanut oil against oxidative deterioration by grinding the peanuts to a paste condition and then subjecting the paste to an elevated temperature.
U.S. Patent 2,198,220 to Musher, issued April 23, 1940, discloses a method for retarding deterioration and rancidity in peanut butter by combining with the regular peanut paste up to 25% peanut paste made from unroasted peanuts.
U.S. Patent 2,496,461 to Fisher, issued February 7, 1950, discloses a process for reducing oxidation and the resulting rancidity of peanut butter by bringing whole roasted peanuts into contact with melted butter which has been heated to a temperature between 250F and 400F, for a period of 10-20 minutes.
U.S. Patent 3,121,015 to Avera, issued February 11, 1964, 2s and U.S. Patent 3,615,590 to Avera et al., issued October 26, ~ 1971, disclose a peanut butter more resistant to ox~dative ; deterioration, prepared by comminuting substantially dehydrated raw peanuts to a fluid slurry and then roasting the slurry.
; 3Q U.S. Patent 3,266,905 to Baker et al., issued August 16, 1966, discloses a process for improv1ng peanut butter - stab~lity, in which through a series of steps dissolved, adsorbed, and entrained oxygen is removed and replaced by an inert gas.

2~20~64 U.S. Patent 3,821,448 to Parker et al., issued June 28, 1974, discloses a process for improving the flavor stability of peanut butter by holding the peanut butter under vacuum with mild agitation to deaerate it, and then packing the peanut butter under nitrogen.
U.S. Patent 4,004,037 to Connick, issued January 18, 1977, discloses a process in which peanuts are ground in the presence of solid carbon dioxide to reduce oxidation of the peanut oil during grinding and also to reduce the amount of lQ oxygen that is dissolved and adsorbed from the peanut butter ingredients. The peanut butter is said to have improved flavor and increased shelf life.
The prior art methods have certain drawbacks, requiring additional processing steps, additional ingredients, and/or increased cost. It would be desirable to have a peanut butter that has increased oxidative stability without the need for the additional measures disclosed in the prior art.
Therefore, it is an ob~ect of the present invention to provide a novel peanut butter having greatly improved 2Q resistance to oxidation and staling.
It is another object of the present invention to provide such a peanut butter without the necessity of added ingredients or processing steps.
It is a further object of the present invention to provide such a peanut butter by the use of particular peanuts described herein as the starting material.
These and other objects of the invention will become evident from the disclosure herein.
All parts, percentages and ratios used herein are by 3~ weight unless otherwise indicated.
Summarv of the Invention _ The invention is a pean~ butter comprising a dispersion of finely divided peanut particles in a continuous oil phase, wherein the oil phase comprises peanut oil derived from peanuts in which the naturally occurring oll has a fatty acid ,, 2020~64 composition such that the oleic:linoleic acid ratio is between about 6:1 and about 40:1. The peanut butter has improved resistance to oxidation and staling.
Detailed DescriDtion of the Inventicn The present invention relates to a peanut butter that is highly resistant to the oxidation and staling that reduces the shelf life of typical peanut butters. The peanut butter stays fresh longer and has improved flavor stability. Packing under nitrogen may be unnecessary, resulting in lower packaging lQ costs and improved fresh roasted flavor.
These advantages are achieved by making the peanut butter from peanuts containing peanut oil having a high ratio of oleic to linoleic fatty acids. Specifically, the present invention is a peanut butter comprising a dispersion of finely divided peanut particles in a continuous oil phase, wherein the oil phase comprises peanut oil derived from peanuts in which the naturally occurring o~l has a fatty acid composition such that the oleic:linoleic acid ratio is between about 6:1 and about 40:1.
At the time of the present invention, it was uncertain that a good tasting peanut butter could be made with high oleic/low linoleic peanuts. Overall peanut butter flavor is not readily predictable. One possibility was that some degree of oxidation is necessary for a complete peanut butter flavor, 2s and therefore that if oxidation is greatly reduced the resulting peanut butter will taste bland. Additionally, it was believed that there is a correlation between roasted peanut flavor and peanut oil oxidation, and that some roasted flavor might be lost if oxidation was reduced. It was 3~ surprisingly discovered that the initial flavor of the present peanut butter is as good as the flavor of conventional peanut _ butters. -~
Moreover, the present peanut butter better retains its good flavor over time. Experiments showed that the roasted flavor of the present peanut butter is also very good. Using 2020~6~

methyl pyrazine as an indicator of roasted peanut flavor and hexanal as an indicator of peanut oil oxidation, it was found that the initial hexanal/methyl pyrazine ratio of the present peanut butter is comparable to that of convent~onal peanut S butters, and that this ratio remained very good after aging under oxidative conditions. By contrast, the hexanal/methyl pyrazine ratios of the conventional peanut butters increased significantly after aging.
The combined teachings of several publications suggest lQ that some loss of flavor might have been expected by making peanut butter with high oleic/low linoleic peanuts. Litman et al. state that lipids are the major source of flavor in foods.
Litman et al., "The Role Lipids Play in the Posit~ve and Negative Flavors of Foodsn, pp. 1, 9, and 15, LiDids as a Source of Flavor, ACS symposium Series 75, American Chemical Society, Washington, DC (1978). Frankel discusses the flavor significance of oxidation of vegetable oils, and states that it is difficult to predict the oxidation contribution of different fatty acids when present in mixtures as in natural fats. Frankel, ~Chemistry of Autoxidation: Mechanism, Products and Flavor Significance", pp. 1 and 12, Flavor Chem1strv of Fats and Oils, American Oil Chemists' Soc~ety, Champaign, Illinois (1985). Pokorny states that the oxidation products of linolenic acids contribute to fried flavor so that food fried ln soybean oil has a rich flavor, and that oxidation products of oleic acid are of lesser importance.
Pokorny, Flavor Chemistrv of DeeD-Fat Frv~na of Oil, Prague Institute of Chemical Technology, Dept. of Food Science, Prague CS-166 28, Czechoslovakia (abstract in JAOCS, Vol. 65, no. 4, p. 482, April 1988). Lastly, Chang et al. state that unsaturated lactones play an important role in deep-fat fried - flavor, and that trilinolejn contains more unsaturated lactones than triolein. This may indicate that some linoleic acid is necessary for frying fat to impart its deep-fat fried flavor. Chang et al., "Chemistry of Deep Fat Fried Flavorn, 2020~6~

pp. 38 and 40, LiDids as a Source of Flavor, ACS Symposium Series 75, ACS, Washington, DC (1978).
Further, the great improvement in oxidation resistance of the present peanut butter was not predictable at the time of invention. Oxidation is complicated, and it is a function of both the catalyst and substrate. The magnitude of the oxidation resistance benefit of the invent~on was not expected.
It is also believed that the peanuts used to make the present peanut butter have an increased resistance to the formation of aflatoxins. There is an ongoing desire in the peanut industry to avoid even trace amounts of aflatoxins in peanut products such as peanut butter. The present high oleic/low linoleic peanuts are thought to be resistant to aflatoxin development because reducing the amount of oxidation interferes with the aflatoxin biosynthesis process.
H~ah Ole~c Peanuts Peanuts suitable for use in the present invention are disclosed in the following ~ournal article which is incorporated by reference herein: Norden et al., "Variability in Oil Quality Among Peanut Genotypes in the Florida Breeding Program~, Peanut Science, Vol. 14, No. 1, pp. 7-11 (January-June, 1987). As disclosed in the journal article, the Department of Agronomy at the University of Florida, Gainesville, Florida, has long been conducting a peanut breed~ng program to improve the quality of peanut oil. The fatty acid compositions of various genotypes in the breeding program are dlsclosed in the article. Two closely related experimental lines known as "435-2--1~ and "435-2--2~ were found to contain about 80% oleic and about 2% linoleic acids.
~hese peanut lines are therefore suitable for use in the _ present invention.
The Norden et al. journal article reports the following propert~es for the peanut oils of the peanut genotypes 435-2--1 and 435-2--2:

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Genotype Genotype Oil Qualitv Trait 435-2--1 435-2--2 Palmitic acid (C16:0) 7 35% 7.16%
Oleic acid (C18 1) 79.91X 79.71%
Linoleic acid (C18:2) 2.14% 2.29%
Eicosenoic acid (C20:1) 1.81% 1.72X
Oleic/Linoleic acid ratio 37.34 34.81 Iodine value 73.93 73.87 Polyunsaturated to 0.138 0.141 lQ saturated acid ratio It is speculated that a natural mutation may have caused the 1l435" peanut lines to have these high oleic acid and low linoleic acid levels. Norden et al. further state that the "435~ genotypes were derived from a seed sample received in 1959 from W. K. Bailey, former Leader, Peanut Investigations, USDA, ARS, CRD, Bettsville, Maryland. The original seed stock was a Florispan derivative, with the possibility of a Spanish outcross. (~Florispan~ is a Spanish peanut grown by the 20. University of Florida.) Between 1968 and 1974, the parental stock of the ~435" peanut line contained peanut oil with about 50.8% oleic acid and about 26.2% linoleic acid.
The 435-2--1 and 435-2--2 peanuts are available in the University of Florida peanut breeding program peanut collection, Department of Agronomy, Gainesville, Florida 32611.
The ratio of ole~c to linoleic fatty acids 1n the peanut oil used to make the present peanut butter is critical, because linoleic acid is very susceptible to oxidation while 3Q oleic acid is much more resistant to oxidation. The peanut oil used in the present peanut butter has an oleic:linoleic - acid ratio between about 6:L~and about 40:1. Preferably, the ratio is between about 15:1 and about 40:1.
It is also preferred that the fatty acid composition of the present peanut oil include between about 0.1% and about 2020afi4 10% linoleic acid, more preferably between about 1X and about 5X. The preferred level of oleic acid is between about 70X
and about goæ, more preferably between about 75% and about 85%.
S The fatty acid composition of the peanuts used to make the present peanut butter is much different from the composition of conventional peanuts. For example, Peanut Science and Technoloqv. American Peanut Research and Education Society, Inc., Yoakum, Texas (1982) at page 664 discloses oleic/linoleic ratios for some typical peanuts ranging between about 1.3:1 and about 2 6:1.
Although the high oleic/low linoleic "435" peanuts disclosed in the Norden et al. journal article are most preferred for use in the present invention, the invention is not limited to these peanuts. Any peanuts with oil having the required fatty acid composition can be used.
Additional Peanut Butter Inqredients As discussed above, the peanut butter of the present invent~on comprises a dispersion of finely divided peanut 2Q particles in a continuous oil phase, preferably about 30-60%
oil phase and about 40-70X peanut particles, and more preferably about 35-55X oil phase and about 45-65% peanut particles. Generally, both the peanut particles and the oil phase compr1s~ng peanut oil will be present in what is known to the industry as the peanut "paste~. Peanut paste is ordinarily obtained by conventional methods of roasting and blanching raw peanuts and then grinding them. The resulting peanut paste is a mixture of peanut particles and peanut oil which have been released from the cellular structure of the 3Q nuts during the grinding operation. The peanut particles are preferably derived from the same peanuts as the peanut oil _ described hereinabove - the preferred embodiment of the present invention is to process the "435~ line of peanuts described above 1nto a peanut paste, and then use the paste in r 9 202~64 the present peanut butter. However, it is also acceptable to extract the "435" peanut oil from the paste and then combine the oil with peanut particles from different peanuts (usually by combining the oil with paste from which the original oil has been extracted or expelled).
In another embodiment of the present invention, the continuous oil phase of the peanut butter comprises a blend of the above-described high oleic/low linoleic peanut oil with other peanut oil, for example peanut oil which is used in lQ current commercially available peanut butters. When a blend of these oils is used, the blend must have a combined fatty acid composition such that the oleic:linoleic acid ratio is between about 3:1 and about 40:1, preferably between about 15:1 and about 40:1. Typically a blend of oils will be obtained simply by using a blend of different peanuts (i.e., the ~435~ peanuts and some conventional peanuts) as the starting material. However, it is also acceptable to extract and then combine oils with defatted peanut paste. The ~other peanut oil" in addition to the high oleic/low linoleic peanut oil can be a single oil or a mixture of different oils.
The present peanut butter preferably additionally comprises from about 1% to about 5% by weight stabilizer, normally comprising a hydrogenated fatty material. It stabilizes the peanut paste against separation of oil and solid components. The stabilizer can include nearly any edible glyceride fat solid or semisolid. Partially or completely hydrogenated natural fats such as peanut oil, corn oil, cottonseed oil, linseed oil, palm oil, whale oil, and other marine oils, alone or in combination, are very suitable 3Q to provide stabilizers. One preferred type of stabilizer is described in U.S. Patent 3,265,5~7 to Japikse, incorporated by _ reference herein: substantiaLly fully hydrogenated soybean oil and substantially fully hydrogenated rapeseed oil in a weight ratio from about 3:7 to about 7:3.

202Q~64 The peanut butter can optionally comprise from about OX
to about 1.5Y. by weight emulsifiers. These e~ulsifiers function in the peanut butter to negate stickiness so that the peanut butter will not stick to the roof of the mouth.
Suitable emulsifiers include lecithin and fatty mono- and diglycerides, for example, soybean mono- and diglycerides.
The present peanut butter can optionally also comprise from about 0% to about 10% by weight added sweetener.
Suitable sweeteners include, for example, sucrose, dextrose, lQ fructose, honey, molasses, polydextrose, aspartame, saccharin, and other common sweetening agents.
The peanut butter composit~on can also additionally comprise from about 0% to about 1.5% by weight salt as a flavoring agent.
The present peanut butter can also contain limited amounts of other fats, oils, or fat substitutes known to the art in addition to the peanut oil and the stabilizer. These other fats or oils can be derived from vegetable or ani0al sources well-known to the art. For example, the peanut butter 2Q can contain a small amount of liquid soybean oil to optimize the taste. Suitable fat substitutes include sugar and sugar alcohol fatty acid polyesters (U.S. Patent 3,600,186 of Mattson and Volpenhein, assigned to Procter & Gamble, issued August 17, 1971, incorporated herein by reference).
This ~nvention is not meant to be limited to the strict definition of "peanut butter~ outlined in federal regulations - it can also include peanut "spreads~.
Processinq steDs Although the present invention is not l~mited by the processing method, typically the ~435~ line of peanuts described hereinabove are roasted and blanched, and then - ground to a part~cle size found in conventional peanut paste.
Then any other peanut butter ingredients are added and mixed to provide a homogeneous mixture. It is preferred that the .

2020~64 processing stream be maintained in an inert atmosphere, e.g. a nitrogen atmosphere, starting just before the grinding step and continuing throughout the remainder of the process. The homogeneous mixture with its stabilizer components in molten state is subjected to processing to properly crystallize the stabilizer. Ordinarily the stabilizer is in molten state when the homogeneous mixture is at a temperature greater than 100F
(38C). The crystallization is carried out by cooling the homogeneous mixture from this temperature, for example, in a lQ scraped wall heat exchanger and then subjecting the mixture to agitation, for example, in a picker. After be~ng processed through the picker the product is ordinarily introduced into containers by a filler, then tempered.
The peanut paste herein can be prepared in a number of ways. For example, it can be prepared by utilizing multiple passes of peanuts through a conventional grinder or other device such as comminuters, attrition mills, disintegrators, hammermills, or colloid mills.
The extent of grinding can be adjusted to produce a 2Q peanut butter that is smooth, regular or chunky in texture.
Smooth peanut butter has a fine, non-grainy texture, while regular peanut butter has a grainy texture with small peanut particles. Chunky peanut butter contains substantial amounts of peanut particles larger than 1/16 inch in diameter. The chunky peanut butter can be made by rough grinding the paste or by mixing chopped nuts with a smooth peanut butter.
Although it is less preferred, a suitable peanut butter according to the present invention can be made simply by grinding roasted peanuts - it is not necessary to add a 3Q stabilizer, or to heat, cool, or agitate the peanut butter.
The present invention, then, is also a process for making ~ a peanut butter, which process in its broadest embodiment comprises roasting and then grinding peanuts to make a dispersion of f~nely divided peanut particles in a continuous .

202~64 peanut oil phase, wherein the peanuts are the high oleic/low linoleic peanuts which have been described hereinabove.
The present peanut butter can be used in confections and snacks. It can be admixed with other ingredients (e.g., S polydextrose) to make peanut creams. Peanut-based fillings can also be made, as well as a variety of other peanut-based foods known to the art.

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AnalYtical Method: FattY Acid ComDosition of the Peanut Oil PrinciDle Capillary gas chromatography is used to separate and quantitate fatty acid methyl esters. The stattonary phase, SP-2340, separates the methyl esters according to:
1) chain length, i.e. C10, C12, C14, C16 are separated 2) degree of saturation, i.e. C18:1, C18:2, C18:3 are separated 3) double bond geometry, C18:1 trans, C18:1 cis are separated 4) double bond position, C18:1 6 cis, C18:1 9 cis, are separated.
The peak areas for each methyl ester are determined electronically. The fatty acid composition, Z trans isomers, and % cis-cis, are determined by summing the appropriate peaks. The iodine value is calculated from the fatty acid composition.

2Q Reference Standards Two reference standards of commercial liquid oils (Crisco~ and Puritan~, Procter & Gamble, Cincinnati, Ohio) are run with each set of samples. The commercial oils have the following fatty acid composition:
Puritan~ Crisco~
Averaae (n-15) Averaqe (n-15) C14:0 0.1 0.1 C16:0 6.9 + 0.4 13.7 + 0.6 C18:0 4.3 + 0.2 11.7 + 0-1 C18:1 19.7 + 0.1 44.7 + 0.1 _ C18:2 66.0~+ 0.1 26.1 + 0.2 C20:0 0.3 0.4 + 0.l 2020~

C18:3 1.~ + 0.1 2.0 + 0.1 C22:0 0.6 0.3 C24:0 0.1 0.1 ApDaratus lQ Gas Chromatograph Hewlett-Packard 5880A, equipped with a capillary injection system and flame ionization detector~
Hewlett-Packard Co., Palo Alto, CA 94304 Autosampler Hewlett-Packard 7671A

Column 60 m x 0.25 mm 2Q fused silica capillary column coated with SP-2340 (0.2 micron film thickness), Supelco ~2-4023, Supelco Inc., Bellefonte, PA
Data System Hewlett-Packard 3350 Laboratory Automation System Syringe lO uL, Hamilton 701N

Operation A. MethYlation Methyl esters of the peanut oil and the reference standards are prepared by transesterification using sodium methoxide. The methyl esters are diluted with hexane (to a concentration of 1%) and then injected into the instrument.

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,5 B. Instrument Condit10ns Set up the instrument conditions for the Hewlett-Packard 5880A as in the following Table I.

Septum Purge - l mL/min Inlet Pressure - 15 psi Vent Flow (Split) - 60 mL/min Make-up Carrier - 30 mL/min lQ H2 - 30 mL/min A1r - 400 mL/min 20~0~64 Table I
INSTRUMENTAL CONDITIONS

LIST
S OVEN TEMP 8 150C SETPT~150C LIMIT ~ 405C
EQUIB TIME - 0.10 MIN.
OVEN TEMP PROFILE: (ANNOTATION Off) INITIAL VALUE # lSOC
INITIAL TIME - 0.00 MIN.

PRGM RATE - 1.30C/MIN.

FINAL TIME - 10.00 MIN.

POST TIME ~ 0.00 MIN.

DET 1 TEMP - 210C SETPT ~ 210C LIMIT ~ 405C
2Q DET 2 TEMP - 0C SETPT - 50C(OFF) LIMIT D 405C
INJ 1 TEMP - 210C SETPT ~ 210C LIMIT - 405C

AUX 1 TEMP - 0C SETPT - 50C(OFF) LIMIT - 405C
AUX 2 TEMP - 0C SETPT ~ 50C(OFF) LIMIT ~ 405C
DEVICE 2: GC TERMINAL 1 SIGNAL ~ B
PLOT - ???
CHART SPEED - 1.00 CM/MIN

7~FFSET - 10 ZERO - 4.73 DEVICE S: (hp) LOOP 1 SIGNAL - B
PLOT - ???

%OFFSET - O
ZERO - 4.73 DETECTOR B: FLAME IONlZATION

_ 2020~A

C. Calibration Unity response factors are used for this analysis.

D. Sample AnalYsis Inject approximately l uL of the methyl ester mixture.

Calculations This analysis normalizes all the fatty acid methyl esters lQ (FAME) which elute from the column so the sum is 100%. The determination of the proper composition of the FAME mixture from this capillary column analysis is dependent on adequate resolution of components into discrste peaks, proper quantitation of the eluted peaks, and prnper assignment of the lS peak indentities.

Fatt~ Acid Composition The fatty acid composition of the peanut oil is reconstructed 2Q by summing the isomers together. For example, all Cl8-l cis and trans isomers are summed together to produce the total C18-l composition. The same is true for Cl8-2. Unlisted components are reported as "OTHER THAN A80VE~. If the ~OTHER~
in the report is greater than 1%, the reported composition is in error because of unidentified peaks. Ident1fied peaks with a composition of less than 0.1% are not listed in the report but are counted in the "OTHER THAN ABOVE~.

The following examples are intended only to further illustrate the invention and are not intended to limit the scope of the invention which is defined by the claims.
._ ,.

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ExamDle 1 A peanut butter according to the present invention is prepared as follows.
The following ingredients are used:
s Ingred1ent Weiaht % Pounds (lbs.) Peanuts~ 90.0 225 Sugar (12x) 5.8 14.5 Salt 1.2 3.0 lQ Molasses 0.5 l.25 Soybean and rapeseed hardstock1.35 3.375 Mono- and diglyceride emulsifier 0.7 1.75 Standard peanut oil 0.45 1.125 lO0.0 250 *The peanuts are ~435-2--l" peanuts as described hereinabove, obta1ned from the Un1versity of Florida.
The peanut oil has the following fatty acid composition:
2Q 6.6% Cl6 0~ 0.1% C16 1, 3.0Y C18:0- 76-0X Cl8:1- 4-2%
Clg 2, 1.7% C20 0, 2.1% C20 l~ 3.9% C22:0- 0-2% C22:1-1.9% C24 0, and 0.4X others. The ole1c~11noleic acid rat10 is 18:1.

The peanuts are roasted at 420F (216C) to a Hunter L
color of about 47, and then cooled to ambient temperature. The cooled peanuts are blanched, colorsorted, ground into a paste, and fed 1nto a kettle heated to 145F (63C). Next the hardstock, emulsifier, molasses, and peanut oil are melted together 1n a steam bath, and then added to the peanut paste and mixed for 5 minutes. The sugar and salt are then added, - and mixed for an add1t10nal 30 minutes.
The hot peanut butter ts homogenized to ach1eve a Hageman particle size of 5Ø The homogeni~ed peanut butter 1s then dearated under vacuum to remove oxygen and prevent oil 20~0~64 separation. The dearated peanut butter is then chilled in two scraped surface heat exchangers to achieve a final temperature of 86F (30C). The chilled peanut butter is then agitated in two pickers operating at nominally 50 rpm before packing into 12 ounce plastic jars. The product is then tempered at 80F
(27C) for 48 hours before use.

Example 2 Two peanut butters are made, one from high oleic/low linoleic peanuts according to the present invention, and the other from conventional southeastern Runner peanuts. The following ingredients are used to make both peanut butters:

Inqredient Wei~ht % Amount Peanuts* 90.1 36.0 lbs.
Sugar (12x) 5.8 2.32 lbs.
Salt 1.1 0.44 lbs.
Molasses 0.5 90.7 9.
Soybean and rapeseed hardstock1.20217.7 9.
Mono- and diglyceride emulsifier 0.7 127.0 9.
Conventional peanut oil 0.60 108.9 9.
100 .0 *The high oleic/low linoleic peanuts have the following fatty acid compositlon: 6.6X Cl6 o~ 2-9% C18:0- 76-6%
C18:1- 4-7% C18:2- and 3.6X C22 0~

The conventional southeastern Runner peanuts have the following fatty acid composition: 10.2% C16 0~ 2.3%
0 -Clg 0, 50.5% C18 1~ 2g.9% C18 2~ 1.2% C20 o~ 1-4% C20:1-2.8X C22 0~ 0.1% C22 1~ and 1.5% C24 0.

Both peanut butters are processed by the same method, which is substantially the same as the method described in Example 1.

2020~64 Shortly after the peanut butters are made, flavor testing is done by expert panelists who are requested to grade the peanut butters in blind tests. A higher average score indicates that the peanut butters taste more peanuty and less stale, while a lower average score indicates more staleness and less peanuty flavor. The high oleic/low linoleic peanut butter receives an average flavor score of 6.50, while the conventional peanut butter receives an average score of 6.11.
It is concluded that the peanut butter made according to the lQ present invention is comparable in flavor to the conventional peanut butter.

Example 3 An experiment is conducted to compare the shelf stability of the peanut butter of Example 1 with that of two control peanut butters.
The first control peanut butter is made from Span1sh Pronto peanuts, us~ng the same ingredient amounts and substantially the same processing conditions as in Example 1.
The peanut oil of the Spanish Pronto peanuts has the following fatty acid composition: 12.3X C~6 o~ 3.4% C18:0- 39-6% C18:1-35-7% C18:2- 1-7% C20:0- 1.0% C20 1, 3.6X C22 0, and 2.8%
others. The oleic/l~noleic acid ratio is 1.1.
The second control peanut butter is made from southeastern Runner peanuts, again using the same ingredient amounts and substant~ally the same processing cond~t~ons as in Example 1. The peanut oil of the southeastern Runner peanuts has the following fatty acid composition: 10.3% C16 o~ 2.SX
C18:0- 52-2% C18:1- 27.1X C1g 2, 3.0% C22 o~ and 4.9% others.
3Q The oleic/linoleic acid rat~o is 1.8.
The peanut butter of Example 1 and the two control peanut _ butters are packed under air into jars, and then jars of each peanut butter are stored at 90F (32C) and 100F (38C).
The jars are aged and tested for flavor after 0, 1, 2, 3, 4 and 6 months. Flavor testing is done by expert panelists as 2020~6~

described in Example 2, with a higher average score indicating that the peanut butters taste more peanuty and less stale, and vice versa.
The results of the flavor testing are shown below in Table 1:

~able 1 Age Flavor Grade (Averaael lQ TemDerature(mos.) SDanish Runner ExamDle I
90F (32C) 0 6.6 7.2 6.3 n 1 6.3 6.4 5.9 " 2 5.9 6.1 6.6 3 S.9 5.9 6.1 4 5.8 5.6 6.0 6 4.7 4.9 5.1 100F (38C) 0 6.6 7.2 6.3 1 5.7 6.6 6.1 ~ 2 5.4 5.7 6.2 ~ 3 4.8 5.0 5.4 4* --- .

* The taste of the peanut butters is too poor for further flavor grading.
The data indicate that under oxidative conditions (high temperature, high oxygen content, long aging), the flavor of the control peanut butters deter;orates more than the flavor of the peanut butter of Example 1. This suggests that less 3Q oxidation is occurring in the peanut butter of Example 1.
The peroxide value of the peanut butters is also measured - after 4 and 6 months at 90F-~(32C). A higher peroxide valueindicates that more oxidat;4n occurs. The measurements are shown below ;n Table 2.
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Table 2 Age Peroxide Value Temperature Lmos.) Spanish Runner Example 1 S 90F (32C) 4 24.79 28.11 6.S6 90F (32C) 6 29.97 39.43 16.19 lQ The results show that the peanut butter of the present invention is much more resistant to oxidation than the control peanuts after aging at high temperature.

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Claims (15)

1. A peanut butter comprising a dispersion of finely divided peanut particles in a continuous oil phase, wherein the oil phase comprises peanut oil derived from peanuts in which the naturally occurring oil has a fatty acid composition such that the oleic:linoleic acid ratio is between about 6:1 and about 40:1.

2. A peanut butter according to Claim 1 wherein the oleic:linoleic acid ratio is between about 15:1 and about 40:1.

3. A peanut butter according to Claim l wherein the continuous oil phase comprises a blend of said naturally occurring oil with other peanut oil, and wherein the blend of oils has a combined fatty acid composition such that the oleic:linoleic acid ratio is between about 3:1 and about 40:1.

4. A peanut butter according to Claim 3 wherein the oleic:linoleic acid ratio of the oil blend is between about l5:1 and about 40:1.

5. A peanut butter according to Claim 1 or 3 wherein the fatty acid composition of the naturally occurring peanut oil includes between about 0.1% and about 10% linoleic acid.

6. A peanut butter according to Claim 5 wherein the linoleic acid composition of the naturally occurring peanut oil is between about 1% and about 5%.

7. A peanut butter according to Claim 1 or 3 wherein the fatty acid composition of the naturally occurring peanut oil includes between about 70% and about 90% oleic acid.

8. A peanut butter according to Claim 7 wherein the oleic acid composition of the naturally occurring peanut oil is between about 75% and about 85%.

9. A peanut butter according to Claim 1 or 3 comprising from about 30% to about 60% by weight continuous oil phase and from about 40% to about 70% by weight peanut particles.

10. A peanut butter according to Claim 9 comprising from about 35% to about 55% by weight continuous oil phase and from about 45% to about 65% by weight peanut particles.

11. A peanut butter according to Claim 9 comprising:
(a) from about 30% to about 60% by weight continuous oil phase;
(b) from about 40% to about 70% by weight peanut particles;
(c) from about 1% to about 5% by weight stabilizer;
(d) from about 0% to about 1.5% by weight emulsifier;
(e) from about 0% to about 12% by weight sweetener; and (f) from about 0% to about 1.5% by weight salt.

12. A process for making a peanut butter comprising roasting and then grinding peanuts to make a dispersion of finely divided peanut particles in a continuous peanut oil phase, wherein the peanuts contain peanut oil having a fatty acid composition such that the oleic:linoleic acid ratio is between about 6:1 and about 40:1.

13. A process according to Claim 12 wherein the oleic:linoleic ratio is between about 15:1 and about 40:1.

14. A process according to Claim 12 wherein the linoleic acid composition of the peanut oil is between about 0.1% and about 10%.

15. A process according to Claim 12 wherein the oleic acid composition of the peanut oil is between about 70% and about 90%.