Method for making a liquid smoke coloring agent solution

A liquid smoke coloring agent solution having total water miscibility, a benzopyrene content under about 5 ppb, and a pH above about 11, and a related method for making same by contacting liquid smoke with water and an alkaline agent. The liquid smoke coloring agent solution may be made from commercially existing liquid smoke compositions.

TECHNICAL FIELD
 The present invention relates, in general, to a liquid smoke composition.
 Such liquid smoke compositions are used to color and flavor edible
 foodstuffs. More particularly, the present invention relates to a
 precipitate from a liquid smoke composition, which precipitate provides an
 improved coloring agent solution.

Table of Abbreviations
 NH.sub.4 OH ammonium hydroxide
 B(a)P benzo(a)pyrene
 Ca(OH).sub.2 calcium hydroxide
 C Centigrade
 F Fahrenheit
 g gram
 mg milligram
 ml milliliter
 ppb parts per billion
 PAH polynuclear aromatic hydrocarbons
 KOH potassium hydroxide
 NaOH sodium hydroxide
 BACKGROUND OF THE INVENTION
 Foods have been smoked, since humans first used fire to prepare meals, to
 provide flavor, color, and preservation. Initially, preservation was the
 ultimate reason to smoke foods, but as food preservation techniques
 advanced, flavor and color became the main reasons to smoke foods. As
 societies became more industrialized, the shift from home or individual
 smoking to processing in specialized plants led the need for improved
 control of smoking procedures, including consistent smoke application
 techniques.
 Consequently, liquid smoke compositions (also known as liquid smoke
 solutions, and colloquially referred to as liquid smokes) were developed
 as a replacement for smoking of food by direct contact with smoke in a
 smokehouse. Such compositions have become a standard industry practice.
 When applied to the surface of meats and other proteinaceous foodstuffs,
 such as various types of sausages, frankfurters, bolognas, beef rolls,
 hams, and the like, liquid smoke gives the item a characteristic smokey
 flavor and produces a dark smoked color. The achievement of a
 smokehouse-like product by application of an aqueous smoke solution to a
 foodstuff requires control and balancing of many variables such as the
 food composition, temperature, humidity, processing time, contact time,
 amount of liquid smoke, and concentration of liquid smoke.
 It is well known to those skilled in the art that liquid smoke compositions
 contain a wide array of chemical compounds, and over 400 such compounds
 have been identified. Nevertheless, it is also well known to those skilled
 in the art that liquid smoke compositions are characterized by their
 content of certain classes of compounds, namely, acids (% titratable
 acidity), phenols, and carbonyls.
 The acids are preservatives, and, of course, pH control agents, as a result
 of which commercial liquid smoke compositions typically have a pH under
 about 2.5, and more typically under about 2.3, and a % titratable acidity
 by volume from about 3% to about 18%. The phenols give flavor, and also
 aroma, to liquid smoke compositions, and commercial compositions typically
 have a phenols content from about 10 to about 45, and more typically, from
 about 14 to about 30 mg/ml. The carbonyls impart the brown color to liquid
 smoke compositions. The phenols and the carbonyls can be measured as
 described in the below-mentioned U.S. Pat. No. 4,431,032 to Nicholson. The
 browning potential of liquid smoke compositions can be measured by the
 well-known in the art Browning Index procedure described in the
 below-mentioned U.S. Pat. No. 4,994,297 to Underwood or by the well-known
 in the art Staining Index procedure involving reaction of liquid smoke
 with glycine. It is noted that the acids and carbonyls are secondary in
 contributing to the flavor of liquid smoke compositions. The color value
 can be measured as described in the below-mentioned U.S. Pat. No.
 5,681,603 to Underwood. The'603 Patent to Underwood also describes how to
 measure B(a)P, which is carcinogenic and thus should be under 10 ppb.
 As general background, improved liquid smoke compositions and techniques
 for their manufacture are described in U.S. Pat. No. 4,154,866 to Dainus,
 Dane, and O'Hara (assignee Stange Co.) and U.S. Pat. No. 4,994,297 to
 Underwood (assignee Ensyn Engineering Associates, Inc.).
 As the advent of liquid smoke compositions has significantly improved meat
 processing, attempts have been made over the last 20 years or so to deal
 with the precipitate problem of liquid smoke. Upon storage of a liquid
 smoke product, the precipitate settles out forming a water insoluble,
 sticky, viscous residue on the bottom of the container for the liquid
 smoke.
 Furthermore, even though liquid smoke is aqueous, liquid smoke is not
 totally water soluble, which exacerbates the precipitate problem. More
 specifically, the precipitate will occur upon dilution of liquid smoke
 with water.
 Nevertheless, the precipitate can be kept in emulsion. For instance, U.S.
 Pat. No. 4,442,868 to Smith and Kearby (assignee Teepak) discloses the
 treatment of liquid smoke with alkaline agents to a pH of 10 or higher to
 dissolve precipitates so they stay in solution and to produce a
 coloring/flavoring agent for casing use. Moreover, not only does U.S. Pat.
 No. 4,446,167 to Smith and Kearby (assignee Teepak, Inc.) disclose the
 formation of a basic smoke flavorant/colorant from natural wood smoke,
 along with food casings and food products utilizing the
 flavorant/colorant, but also this U.S. patent is closely related to the
 disclosure of '868 to Smith and Kearby. Also, as described in U.S. Pat.
 No. 5,690,977 to Hammer, Mans, and Winter (assignee Hoechst AG), disclosed
 is a modified liquid smoke solution that contains an unmodified aqueous
 liquid smoke solution and an alkaline neutralizing agent. The composition
 also includes a synthetic or natural oil, a viscosity increasing component
 and one or more emulsifiers. The liquid smoke mixture is disclosed as
 containing the alkaline neutralizing agent in an amount such that the
 mixture has a pH of about 8 to about 14, and preferably of about 8.5 to
 about 12.
 Alternatively, the precipitate can be removed, which may be achieved by a
 solvent extraction process used on liquid smoke to create a desirable
 tar-depleted liquid smoke supernatant fraction and an undesirable
 tar-containing fraction, followed by gravity separation of the two
 fractions, as is described in U.S. Pat. No. 4,431,032 to Nicholson
 (assignee Union Carbide Corporation). Also, U.S. Pat. No. 4,604,309 to
 Goldberg (assignee Teepak, Inc.) discloses a method for producing a liquid
 smoke solution which includes the step of neutralizing liquid smoke with a
 base such as sodium hydroxide to a pH of 6 to 7, which causes tar to
 precipitate. The precipitate is discarded. The aqueous portion can be
 extracted with organic solvents before or after treatment with the base.
 Furthermore, U.S. Pat. No. 4,834,993 to Chiu (assignee Viskase
 Corporation) discloses a liquid smoke solution that is prepared by
 precipitating tars via neutralizing an acidic liquid smoke composition
 followed by subsequent discarding of the tars. The neutralized liquid
 smoke composition preferably retains a pH of 5 to 9. Additionally, U.S.
 Pat. No. 5,637,339 to Moeller (assignee Hickory Specialties, Inc.)
 discloses treating liquid smoke with activated carbon particles to remove
 tars and create a tar-depleted liquid smoke that is totally water
 miscible.
 Of more particular interest in relation to the present invention is the
 process of U.S. Pat. No. 4,278,694 to Chiu (assignee Union Carbide
 Corporation), which discloses methods for preparing aqueous liquid smoke
 compositions, including a concentrated aqueous liquid smoke composition.
 The concentrated aqueous liquid smoke composition is prepared by
 substantially neutralizing a liquid smoke solution containing smoke
 coloring and flavoring constituents to a pH of greater than about 4 with
 an alkaline neutralizing agent to form a precipitate of smoke tars. The
 smoke tars precipitate is then separated from the supernatant liquid and
 is then subsequently dissolved in a water soluble alcohol solubilizing
 agent to form a smoke tars liquid smoke composition having greater than
 about 15% by weight of dissolved smoke tars. The stated pH range for
 neutralized compositions is from about 4 to about 8. The precipitate is
 derived from a substantially unrefined liquid smoke source and thus
 includes a high concentration of tars, including high levels of
 undesirable components of tar, including benzo(a)pyrene, now known to be a
 carcinogen. An improvement is shown in the more recent U.S. Pat. No.
 5,681,603 to Underwood (assignee Red Arrow Products). More specifically,
 Underwood discloses making a coloring/flavoring composition by contacting
 water insoluble tar by-product (from liquid smoke) with an alkaline
 solution to an end pH above 10. The tar solution is then contacted with
 certain non-ionic aromatic hydrocarbon-based resins to reduce the
 benzo(a)pyrene content to 10 ppb or less.
 The disclosures of all of the above-mentioned patents are incorporated
 herein by reference.
 Despite the above-discussed procedures to use the removed precipitate
 components of liquid smoke (such as using tar as described in '694 to Chiu
 and '603 to Underwood), nevertheless, problems still exist with such
 procedures. For instance, the process of '603 to Underwood has a shortfall
 in that the process includes a time-consuming contact step with the resin
 to remove the carcinogenic benzo(a)pyrene.
 Thus, it is desirable to find an improved liquid smoke composition that is
 made from precipitate and a method for the manufacture thereof, which
 composition and method obviate the above-mentioned problems.
 SUMMARY AND OBJECTS OF THE INVENTION
 Accordingly, the present invention provides a method for making a liquid
 smoke coloring agent solution. The method comprises the step of contacting
 with water and an alkaline agent a starting-material liquid smoke
 composition. The starting-material liquid smoke composition includes an
 organic component, which will fall out as an organic precipitate when the
 starting-material liquid smoke composition is contacted with water. The
 contacting with water and an alkaline agent produces a liquid smoke
 coloring agent solution that has an alkaline pH above about 11, that is
 totally water miscible, and that possesses a benzo(a)pyrene content less
 than about 5 parts per billion free of treatment of the liquid smoke
 coloring agent solution for benzo(a)pyrene removal.
 Additionally, the present invention provides for a liquid smoke coloring
 agent solution comprising a totally water-miscible liquid smoke coloring
 agent solution, which (i) possesses a benzo(a)pyrene content less than
 about 5 parts per billion absent treatment for removal of benzo(a)pyrene,
 (ii) has a pH above about 11, and (iii) is derived from a
 starting-material liquid smoke composition containing an organic
 component, wherein the organic component will fall out as an organic
 precipitate from contacting the starting-material liquid smoke composition
 with water.
 Preferably, the final liquid smoke coloring agent solution has a phenols
 content above about 35 mg/ml and/or a color value above about 500.
 The present invention also contemplates a food casing treated with the
 liquid smoke coloring agent solution. The treatment may be by spraying the
 solution onto a surface of the casing, or in the event that the casing is
 of extruded polymeric plastic film, the solution may be sprayed onto a
 surface of the film or may be incorporated into the extruder with the
 polymeric resin beads and thus blended into the resultant plastic film.
 The present invention also contemplates a proteinaceous foodstuff, such as
 various types of sausages, frankfurters, bolognas, beef rolls, hams, and
 the like, treated with the novel liquid smoke coloring agent solution.
 Accordingly, it is an object of the present invention to provide a liquid
 smoke coloring agent solution and related method of manufacture, wherein
 the solution will not form tar precipitate upon dilution with water.
 Hence, it is an advantage of the present invention that the liquid smoke
 coloring agent solution is totally water miscible since when it is applied
 to foodstuffs or food casings it may be diluted with water but will not
 form tar precipitates that gum the piping system of the application
 apparatus.
 It is a further advantage that the liquid smoke coloring agent solution of
 the present invention is extremely low in B(a)P and thus is not
 carcinogenic, absent treatment for removal of B(a)P.
 Some of the objects and advantages of the invention having been stated
 above, other objects, as well as other advantages, will become evident as
 the description proceeds, when taken in connection with the Laboratory
 Examples and detailed description below.

DETAILED DESCRIPTION OF THE INVENTION
 Traditionally, the water-insoluble precipitate, after isolation from the
 liquid smoke composition, is discarded. As demonstrated hereafter, the
 present invention is directed to a method of preparing a smoke coloring
 and flavoring from this water-insoluble precipitate, thereby providing a
 commercially useful product and substantially reducing the volume of
 discarded precipitate.
 The present invention is directed to a liquid smoke coloring agent solution
 manufactured by contacting a starting-material liquid smoke composition
 with water to cause an organic component of the starting-material liquid
 smoke composition to precipitate out. Then, the pH of the organic
 precipitate is adjusted to above about 11.0, more preferably about 11.4 or
 more, and even more preferably about 11.8 or more, with an alkaline agent
 (such as NaOH, KOH, Ca(OH).sub.2, or NH.sub.4 OH), resulting in a liquid
 smoke coloring agent solution. Optionally, a portion of the alkaline agent
 may be added to the liquid smoke composition prior to the addition of the
 water, as further explained below. The resultant liquid smoke coloring
 agent solution of the invention has a low B(a)P under about 5 ppb, more
 preferably under about 3 ppb, and even more preferably under about 1 ppb,
 free of any treatment of the resultant liquid smoke coloring agent
 solution to remove B(a)Ps. Moreover, the resultant liquid smoke coloring
 agent solution of the invention possesses excellent color capability as
 well as flavoring capability.
 As is well known, water-insoluble precipitates from liquid smoke
 compositions typically contain in excess of 100 ppb of B(a)P. Many
 polynuclear aromatic hydrocarbon compounds, including B(a)P, are known
 carcinogens. Thus, up to now, it was important to reduce the PAH content
 of any composition (made from precipitate and used to contact a foodstuff)
 as much as possible. Specifically it was important to reduce the
 concentration of B(a)P, which is known as a potent carcinogen, to about 10
 ppb or less, and preferably to about 1 ppb or less, but such treatment is
 unnecessary with the present invention.
 In the Laboratory Examples below, in order to produce a liquid smoke
 coloring agent solution, a liquid smoke composition (containing an organic
 component that precipitates out from contact with water) treated by the
 method of the present invention was Code 10 as the starting material. Code
 10 is commercially available from Hickory Specialties, Inc., of Brentwood,
 Tenn. Additionally, the liquid smoke composition starting material
 employed may be SUPERSMOKE, also commercially available form Hickory
 Specialties, Inc., and manufactured by a well known vacuum evaporation
 process that concentrates Code 10 by removing some of the water from Code
 10. As a result, SUPERSMOKE has a typical acidity of about 16%, whereas
 Code 10 has a typical acidity of about 11%. Other commercially available
 liquid smoke compositions also may be employed as the starting material
 with the method of the present invention to produce a liquid smoke
 coloring agent solution, as long as the starting-material liquid smoke
 composition is not totally miscible with water (i.e., a precipitate falls
 out when water is added), and has a low B(a)P under about 10, more
 preferably under about 5, and even more preferably under about 1 ppb.
 Moreover, as can be seen from the Laboratory Examples below, the inventive
 method produced a resultant liquid smoke coloring agent solution and when
 the resultant was then diluted with water, no tar precipitated. Thus, the
 resultant was totally miscible with water.
 With the present invention, the contact of the starting-material liquid
 smoke composition with water and the alkaline agent in order to produce a
 liquid smoke coloring agent solution should be under ambient conditions of
 temperature and pressure. Furthermore, the time of contact is not
 particularly long, and depending on the particular type and amount of
 ingredients, the contact time only needs to be sufficient to cause the
 organic precipitate to fall out and then go into aqueous solution.
 Batch processes, wherein the liquid smoke composition is placed in a
 container with stirring, followed by filtration to separate the organic
 precipitate from the liquid smoke composition, may be employed. Besides
 filtration, the method to separate the organic precipitate may include
 gravity decanting, liquid cycloning, and centrifugal decanting.
 The resultant liquid smoke coloring agent solution of the present invention
 typically has a phenols content (indicative of flavor) of at least about
 35, more preferably at least about 40, and even more preferably about 45
 or more mg/ml, and a color value of at least about 500, more preferably at
 least about 600, and most preferably about 650 or more.
 Additionally, food casings may be treated with the liquid smoke coloring
 agent solution. In the event that the casing is the fibrous type, the
 treatment may be by spraying the solution onto a surface of the casing.
 Typical fibrous casings are cellulosic in nature. In the event that the
 casing is of extruded polymeric plastic film, the solution may be sprayed
 onto the surface of the film. Alternatively, the solution may be
 incorporated into the extruder with the polymeric resins beads and thus
 blended into the resultant plastic film. Typical polymeric plastic films
 include, but are not limited to, films of polymers selected from the group
 consisting of ethylene vinyl acetate, ethylene acrylic acid, ethylene
 methacrylic acid, linear low density polyethylene, very low density linear
 low density polyethylene (sometimes referred to as ultra low density
 polyethylene), and combinations of the polymers.
 Additionally, a proteinaceous foodstuff may be treated with the liquid
 smoke coloring agent solution, such as by spraying on the surface of the
 proteinaceous foodstuff. Examples of various types of proteinaceous
 foodstuffs include, but are not limited to, sausages, frankfurters,
 bolognas, beef rolls, hams, and combinations of the proteinaceous
 foodstuffs.
 Laboratory Examples
 In the Laboratory Examples below, the methods used to determine the phenols
 and the carbonyls are well known to those skilled in the art and are set
 out at columns 11 and 12 in the above-mentioned U.S. Pat. No. 4,431,032 to
 Nicholson. Furthermore, in the Laboratory Examples below, the methods used
 to determine the ppb of B(a)P and the color are well known to those
 skilled in the art and are set out, respectively, at columns 7 and 8 and
 at column 20 in the above-mentioned U.S. Pat. No. 5,681,603 to Underwood.
 Also, in the Laboratory Examples below, the methods used to determine the
 staining index and the acid percent are well known to those skilled in the
 art, and are set out as follows:
 Staining Index
 Reagent of 2.5% Glycine in 95% Acetic Acid. Slurry 2.50 gram of glycine
 (Eastman #445) with 5.0 ml distilled water in a 150 ml beaker. Add about
 70 ml glacial acetic and heat on a steam bath, stirring occasionally to
 dissolve the glycine. Transfer to a 100 ml volumetric flask, cool to room
 temperature, and make to volume with glacial acetic acid which is used to
 rise the original beaker. Filter the solution prior to use if any glycine
 crystallizes out. The solution is stable for at least 3 weeks, and
 probably indefinitely.
 5% Liquid Smoke Solution. Dilute 2.50 ml of liquid smoke to 50.0 ml with
 glacial acetic acid.
 Reaction
 1. Using two 25 ml graduated test tubes, add 1.0 ml of the 5% liquid smoke
 solution to 10.0 ml of glycine reagent and add 1.0 ml of the 5% liquid
 smoke solution to 10 ml of glacial acetic acid (blank).
 2. Cover each tightly with a square of parafilm, and mix by swirling and
 place in a water bath at 85.degree. C. for 30 minutes.
 3. Transfer each to a cold water bath and dilute partially with distilled
 water to speed cooling. When each is at room temperature, finish diluting
 each to the 25 ml mark and mix by inversion.
 4. Set a spectrophotometer to 0 using distilled water. Read the absorbance
 of each solution in a 0.5 inch cuvette using a spectrophotometer at 440
 millimicrons.
 5. Calculate the net absorbance by subtracting the reading of the blank
 (consisting of 1.0 ml of 5% liquid smoke solution, 10.0 ml glacial acetic
 acid, and distilled water to 25 ml) from the reading of the test sample.
 6. Calculate the staining index: Sl=Net Absorbance.times.100.
 Percentage of Acetic Acid
 Pour 250 ml of distilled water into a clean 400 ml beaker. Introduce 6 ml
 of liquid smoke. Standardize pH meter with pH 7 buffer solution. The pH
 meter should be on 7.00. If not, use control knob and place it there.
 Rinse off glass electrode with distilled water from spray bottle. Place
 beaker of water-smoke mixture on testing platform, and lower pH
 electrodes. Stir mixture, adding in standard 1.0 Normality sodium
 hydroxide solution. Add the sodium hydroxide until pH meter reads 7.00.
 The amount of milliliters of sodium hydroxide put into the water-smoke
 mixture is the percentage of acetic acid. For instance, 1 ml of sodium
 hydroxide entering into the smoke-water mixture will count 1 point acetic
 acid until the pH meter reaches a value of 7.00. In other words, if 9.4 ml
 of 1.0 N NaOH solution is introduced, the acetic acid reading will be 9.4%
 of acetic acid by volume. The calculations are as follows:
 % acetic acid=[(ml of NaOH).times.(Normality of NaOH).times.0.1 (correction
 to %).times.(equivalent weight of acetic acid)] divided by ml of liquid
 smoke. % acetic acid=[(9.4 ml of NaOH).times.(1.0
 Normality).times.(approximately 60)] divided by 6.0 ml of liquid smoke,
 and thus, % acetic acid=9.4.
 It is noted that some information was not taken in early tests since it was
 not typical of the type of product involved. The acidity and carbonyls
 cannot be measured or have no meaning in an alkaline environment. The
 color test is not run on low pH (acidic) smoke products since they are
 tested for stain index values.
 EXAMPLE 1
 A liquid smoke composition having a titratable acidity of 10.8% (Code 10
 from Hickory Specialties,Inc.) was placed in a container and mixed with
 water to a titratable acidity of 3.0%. The addition of water caused an
 organic fraction to precipitate and settle to the bottom of the container.
 (During this 1st test and repeats, the amount of precipitate ranged from 3
 to 15% by weight of the original amount of Code 10.) An aliquot of the
 precipitate was mixed with 50% NaOH and the reaction temperature was
 raised to 150.degree. F. (65.6.degree. C.). Then, the mixture was diluted
 with additional water to a final water content of 50% for viscosity
 control. The final coloring agent solution had a pH of 12 and is
 designated in Table 1 below as the 1st sample.
 A second sample was prepared in a manner similar to the first sample.
 However, in this sample, the additional dilution water was added before
 the addition of NaOH, and also, the temperature was held below 125.degree.
 F. (51.6.degree.C.).
 The final coloring agent solution is designated in Table 1 below as the 2nd
 sample.
 The procedure of the second sample was repeated but the reaction
 temperature was raised to 160.degree. F. (71.degree. C). The final
 coloring agent solution is designated in Table 1 below as the 3rd sample.
 TABLE 1
 (%)
 (%) Carbonyls Phenols Water B(a)P
 Sample Acidity pH Color (g/100 g) (mg/ml) Dilution (ppb)
 Code 10 10.8 2.1 ** 18 17 -- 0.5
 (starting
 material)
 1st -- 12 656 -- -- 50 &lt;1
 2nd -- 12 650 -- -- 50 --
 3rd -- 12 697 -- 45 50 --
 **Instead of color, stain index was determined to be 85.
 EXAMPLE 2
 A liquid smoke composition having a titratable acidity of 11.0% (Code 10
 from Hickory Specialties, Inc.) was placed in a container and treated with
 50% NaOH until the pH was 6.0. The addition of NaOH caused an organic
 precipitate to form, which settled to the bottom of the container. An
 aliquot of the precipitate (38.8 g) was mixed with 17.5 ml of 25% NaOH
 solution. Then, 17.5 ml of dilution water was added to adjust viscosity.
 The final coloring agent solution had a pH of 12 and is designated in
 Table 2 below as the 1st sample.
 TABLE 2
 (%)
 (%) Carbonyls Phenols Water B(a)P
 Sample Acidity pH Color (g/100 g) (mg/ml) Dilution (ppb)
 Code 10 11.0 2.1 ** 19 17.5 -- 0.5
 (starting
 material)
 1st -- 11.8 673 -- -- 49.8 0.8
 **Instead of color, stain index was determined to be 85.
 EXAMPLE 3
 The procedure of Example 1 may be repeated but with SUPERSMOKE instead of
 Code 10. The results should be as reported in the following Table 3.
 TABLE 3
 (%)
 (%) Carbonyls Phenols Water B(a)P
 Sample Acidity pH Color (g/100 g) (mg/ml) Dilution (ppb)
 SUPER- 16.0 2.0 ** 37 38 -- 0.8
 SMOKE
 (starting
 material)
 1st -- 12 690 -- -- 50 &lt;1
 **Instead of color, stain index was determined to be 180.
 EXAMPLE 4 (TREATMENT OF FOODSTUFFS)
 Various proteinaceous foodstuffs may be treated with the liquid smoke
 coloring agent solutions from Example 1 (samples 1 through 3) and Example
 2 (sample 1).
 The foodstuffs that may be treated by applying each of the liquid smoke
 coloring agent solutions to the surface of the foodstuffs are sausages,
 frankfurters, bolognas, beef rolls, and hams.
 Excellent color and flavor should be obtained.
 EXAMPLE 5 (TREATMENT OF FOOD CASINGS)
 Food casings may be treated with the liquid smoke coloring agent solutions
 from Example 1(samples 1 through 3) and Example 2 (sample 1).
 Selected casings may be cellulosic fibrous casings and may be treated by
 individually spraying each liquid smoke coloring agent solution onto the
 surface of each respective casing.
 Selected casings may be extruded polymeric plastic films and may be treated
 by individually spraying each liquid smoke coloring agent solution onto
 the surface of each respective casing.
 Selected casings may be extruded polymeric plastic films and may be treated
 by individually incorporating each liquid smoke coloring agent solution
 with each respective kind of polymeric resin beads and thus blending each
 of the solutions into each of the resultant films.
 The polymeric plastic films may be of ethylene vinyl acetate, ethylene
 acrylic acid, ethylene methacrylic acid, linear low density polyethylene,
 very low density linear low density polyethylene, and combinations
 thereof.
 The same foodstuffs (either treated or untreated) as recited in Example 4
 may be packaged with the various treated casings, and the packaged
 foodstuffs should have excellent color and flavor.
 It will be understood that various details of the invention may be changed
 without departing from the scope of the invention. Furthermore, the
 foregoing description is for the purpose of illustration only, and not for
 the purpose of limitation--the invention being defined by the claims.