CA1242106A - Smoke flavor concentrate - Google Patents
Smoke flavor concentrateInfo
- Publication number
- CA1242106A CA1242106A CA000460368A CA460368A CA1242106A CA 1242106 A CA1242106 A CA 1242106A CA 000460368 A CA000460368 A CA 000460368A CA 460368 A CA460368 A CA 460368A CA 1242106 A CA1242106 A CA 1242106A
- Authority
- CA
- Canada
- Prior art keywords
- smoke
- solution
- concentrated aqueous
- smoke solution
- carbonyls
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Food Preservation Except Freezing, Refrigeration, And Drying (AREA)
Abstract
Abstract of the Disclosure A method of producing a concentrated aqueous smoke solution which comprises evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
A concentrated aqueous smoke solution, produced by the method, containing active carbonyls to give a browning index of at least about 15 and up to about 35.
A method of imparting smoke flavor to an edible product comprising contacting an edible product with a sufficient amount of the described concentrated aqueous smoke solution to impart smoke flavor to the edible product.
A concentrated aqueous smoke solution, produced by the method, containing active carbonyls to give a browning index of at least about 15 and up to about 35.
A method of imparting smoke flavor to an edible product comprising contacting an edible product with a sufficient amount of the described concentrated aqueous smoke solution to impart smoke flavor to the edible product.
Description
This invention relates to processes for producing aqueous smoke solutions for smoke flavoring edible products, and the aqueous smoke solutions so produced. More particu-larly, this invention is concerned with the evaporative vacuum concentration of liquid smoke solutions, the concen-trate so produced and use of the concentrate in smoking edible products.
Background of the Invention Aqueous smoke Elavorings are routinely used as a substitute for vaporous smoking in the meat and food industry. The elimination of polycyclic aromatic hydrocarbons and particulate emissions, and the uniformity of the smoke flavor, are the major advantages that processors experience with the use of liquid smoke.
At the present time, liquid smoke solutions are applied to edible products by (1) direct addition to meat emulsions or other food products, (2) spraying with, or dipping the edible product in, liquid smoke, or (3) vaporizing or atomizing the liquid smoke and exposing the product to the smoke vapors. After applying the smoke solution, the food product is usually heated so that the smoke components react with the food product. This produces the same typical smoked flavor normally produced with the traditional vaporous smoking process.
When the commercially available aqueous smoke solutions produced by burning wood with a limited amount ox air (U.S. patents 3,106,473 and 3,873,741) are used, several problems are experienced which limit use of the liquid smoke. Some of the liquid smoke organic components are marginally soluble in aqueous solutions and tend to `.~
react and form polymeric solids in the aqueous smoke solu-tions. These solids cause problems in handling when attempt ing to atomize s~.oke solutions and, also, they create dark tar-like specs on the smoked edible products.
Another feature ox currently available aqueous smoke solutions is the limited amount oE smoke components that are absorbed into the water during the extraction process of smoke flavoring manufacture. As the concentration of liquid smoke surpasses 12~ total acidity, as acetic acid, the absorption of phenolic substances from smoke increases dramatically thus causing an imbalance of smoke components in the final product. With high phenolic contents in smoke solutions, the flavor becomes very harsh and medicinal in nature. These high phenolic smoke solutions also have poor stability and tend to lose color forming potential fairly rapidly.
Another disadvantage in the currently available methods of producing aqueous smoke flavorings is that as the concentration of smoke solution increases in the production system, the efficiency of the recovery system decreases. The cost of production of hither concentrations of aqueous smoke solutions increases disproportionately with increase in flavor and intensity.
Also, quite often currently available aqueous smoke solutions have a concentration of smoke components too low to allow for proper smoke color and flavor to develop using the s-tandard smoke application systems.
Because of the amount of water present in aqueous smoke solutions, sufficient smoke solids are not always deposited on meat products, with atomization or vaporization, to produce the desired smoke color or flavor intensity.
U.S. patent No. 4,112,133 discloses a method of eliminating the precipitated solids in aqueous smoke solutions by admixing a natural liquid smoke solution with an acidulating agent and a solubilizing agent. The process eliminates the precipitation of solids in solution but it creates an imbalance in the ratio of acid to smoke coloring components, thus reducing the browning potential of the resulting smoke solution.
Several methods of concentrating liquid smoke flavorings have been reported in the patent literature.
In U.S. patent No. 4,278,694, to Chiu, a method of concen-trating liquid smoke solutions by boiling in the presence of a water soluble alcohol solubilizing agent is described.
The resultant concentrated solution contains a higher level of some of the smoke constituents but it is greatly reduced in acid concentration. These smoke concentrates are specifically designed for application to food casings where acid causes detrimental effec-ts on the cellulose polymeric structure of the casing. however, the concentrated smoke produced by the Chiu method is not practical for external application to meat and food products due to the significant quantity of alcohol solubilizing agent present and needed in the concentrate to keep the smoke constituents in solution. Also, by concentrating the liquid smoke as described in his method, a significant reduction in color forming potential of the smoke concentrate is experienced.
U.S. patent No. 4,359,481, to Smits and rrimmermans, discloses a method of producing a liquid smoke concentrate which uses Eractional separation by step-wise cooling of vaporous smolce to obtain the concentrate. With the temperature ranyes used in condensing the smoke vapors, the majority oE the smoke flavor phenols are lost in the -two tar fractions since most of the smoke flavor phenols have boiling points near or higher than 200C. The smoke flavor phenols are the compounds normally responsible for the antioxidant and antimicrobial properties of smoke and certainly would be desired in a whole smoke flavor concentrate. In fact, Smits et al recommend adding BRA
(butylated hydroxy anisole) or BUT (butylated hydroxy toluene) to the liquid smoke concentrate for increased keepability.
Other smoke flavor concentrates produced according to U.S. patent Nos. 3,806,609; 3,903,2~7; 4,136,206; 4,154,866;
and 4,250,199 are designed primarily to concentrate the smoke flavor phenols and they do not contain the proportionate level of smoke carbonyls or browning components that are present in vaporous smoke or commercially available liquid smoke solutions. These smoke concentrates are designed as flavor additives and are not suitable for external application to meat and other food or edible products, via atomization or vaporization.
Preparation of a concentrated aqueous smoke flavoring with browning ability, flavor, antioxidant and antimicrobial properties proportionate to commercially available aqueous smoke flavorings would be highly desirable.
The advantages of such a smoke concentrate would be tha-t in its application to meat products, shorter atomization periods wound be needed, thus reducing production costs.
Less humidity would result from the atomization, which would allow shorter time to dry the products and better color formation. Also, a reduction in transportation 3~
and packaging costs per unit of flavor in the aqueous smoke flavoriny could be achieved by its being more concen-trated.
summary ox -the Invention With the present invention, aqueous smoke concen-trates, having a balanced proportion of smoke components that can provide the aforementioned advantages, are produced from commercial aqueous liquid smoke. The concentrates also have the unique characteris-tic of being essentially free of settable tars or precipitates normally experienced in commercially available liquid smoke solutions and a disproportionately high level ox active carbonyls compared to acid content which is reduced during the evaporative concentration method of the invention. When applied exter-nally to meat products, a significant improvement in color formation is observed in the final processed meat product over thaw ox commercial liquid smokes.
According to one aspect of the invention, a method of producing a concentrated aqueous smoke solution is provided which comprises evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
Also provided is a concentrated aqueous smoke solution produced by the method, and especially a concentrate containing at least about 25 mg/ml ox phenolic compounds and up to about 55 mg/ml of these compounds, wormed by increasing the phenolic compounds content 1.5 to 5 times f r~O~
that of a star ting aqueous smoke solution containing about 8 to 20 mg/ml oE phenolic compounds. A smoke flavoring concentrate having the stated phenolic concentrations will have a browning index level from about 15 to about 35 and is obtained by concentrating starting aqueous smoke solutions with browning indices of about 5 to about 13.
Practically, the browning index of the concentrate is raised at least by about 5, desirably by about 10, browning indices from the starting solution.
The invention also provides a method of imparting smoke flavor to an edible product comprising contacting an edible product wi-th a sufficient amount of a concentrated aqueous smoke solution to impart smoke flavor to the edible product; and the concentrated aqueous smoke solution being produced by evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
Even though there is a reduction in acidity by evaporative concentration according to -the described method, there is no otherwise to be expected reduction in browning index in the concentrates. While some browning ingredients boil at a temperature lower than water and would be expected to be lost by evaporation, there is nevertheless a desirable increase ln browning index of the concentrates produce by the invention, rather than a browning index decrease Furthermore, the stability of the concentrates is substantially greater than that of the starting aqueous smoke solutions. This is unexpected since it would have been expected that concentrating the smoke solution, which concentrates reactive ma-terials which could polymerize, would have led to products which settle out in increased amount and quicker Brief Description of the Drawings Figure 1 is a graph which plots the increase in concentrate viscosity with increase in concentration as measured in Brix units; and Figure 2 is a graph which plots browning index and carbonyl content of a commercial liquid smoke heated to various temperatures.
Detailed Description of the Invention Although most aqueous smoke solutions can be suitably concentrated by vacuum evaporative concentration according to the invention, it is presently considered most advantageous to use as a starting material an aqueous smoke solution obtained by contacting natural wood smoke with water in countercurrent flow as disclosed in Hollenbeck U.S. patent No. 3,106,473. Products produced according to that method are available commercially in various grades from Red Arrow Products Company, Manitowoc, Wisconsin under -the trademark CHARSOL conkaining different concentra-tions of acids, phenols and carbonyls, the key components in liquid smoke solutions.
While the starting solution need not contain any minimum amount of smoke flavors, it is generally more efficient to use an aqueous smoke solution containing active carbonyl substances giving a browning index ox at least 5, and desirably at least 7~ as the starting Lo solution. Furthermore, while there is no maximum amount of active carbonyls which can be present, it i5 generally best to employ as a starting solution, one which has active carbonyls giving a maximum browning index ox about 13, since that is the practical maximum concentration in solutions obtained by the process o the Hollenbeck U.S. patent No. 3,106,473.
No specific type of vacuum evaporator need be used to concentrate the aqueous solution. Rotary evaporators, sin91e effect and multiple effect evaporators are suitable.
Conventional evaporators now used commercially to concentrate various products can be used to concentrate aqueous smoke solutions.
The evaporative concentration process of the invention is readily effected by heating the starting aqueous smoke solution under vacuum in an evaporator to a temperature sufficiently high to vaporize water which is then removed until the product is concentrated to the desired amount. At present, it is considered optimum to employ a high vacuum, such as about 23 to 29 in. of ~g, and a vapor temperature of about 75 to 150F. Obviously, the lower the temperature of evaporation the better, but the very high vacuum necessary to evaporate at low temperature is not practical in most commercial evaporators. Temperatures above 150F are not necessary and, in general, should be avoided, especially in systems with prolonged residence time, to limit possible polymerization reactions among the smoke components during concentration.
The evaporation is continued until the desired increase in concentration is obtained. In general, the concentration is continued until the initial active carbonyl concentration of the smoke solution has been increased about 1.5 to 5 times (X), with the grea-test increase in concentration generally being effected with starting solutions having lower active carbonyl concentration. Especially useful concentrates are -those having a browning index of at least 15 such as can be produced by two-fold concentra-tion of a starting smoke solution with a 7.5 browning index. Furthermore, it is generally unnecessary to produce a concentrate having greater than a 35 browning index.
One of the important Eactors in preparing a concentrate for ease of application without dilution is the viscosity ox the solution. Figure 1 shows the increase in viscosity on concentrating a smoke solution from a s solids content of 25 Brix (CharSol C-10; Example 4) to about 68 Brix (Example 4; Run No. 2). With this concentra-tion, the viscosity increases to about 65 centipoises.
Above 65 centipoises, the solution becomes too viscous to be applied by atomization without considerable difficulty or without making special adaptations.
While the water vapor exiting the evaporator contains mainly acids and some minor levels of other compo-nents from the smoke solution, it need not be recovered and be reintroduced into the concentrate since the concen-trated smoke solution retains a very desirable balance of acids, phenols and carbon~ls for smoke Elavoring foods and imparting a desirable brown color.
Residence time in the evaporator, at the elevated temperatures, should be as short as possible to limit possible polymerization reactions. After the concentrate is discharged from the evaporator, it should be cooled to 70F as soon as possible to maintain the browning potential of the liquid smoke.
-I fr~l de rh 3~5 The liquld smoke concentrate, produced by the present invention, has a balanced proportion of smoke components that is fairly similar to that of commercial liquid smoke solutions. Accordingly, the flavor concentrates can be used in the same flavor application processes as commercial liquid smoke solutions without any major processing changes. Usage levels of the smoke concentrate, however, would be substantially less as the rate of concentration increases.
In the present invention, the recovery of the critical smoke constituents, phenols, total carbonyls, and active browning carbonyls in the concentrate is good.
The unique feature of this concentration process is the recovery of the browning carbonyls. This recovery is substantially greater than would be predicted, based on boiling points of the active carbonyls. For example, two of the important active carbonyls of wood smoke, glyoxal and pyruvaldehyde, boil at temperatures well below that o-E the boiling point of water. Yet the recovery of active carbonyls giving good browning indices in the concentrates produced by this process is unexpectedly high.
Another unique feature of this process is that in spite of a disproportionate loss of the acidic components, good solubility of the phenolic and carbonyl substances is still maintained, giving freedom from tar and providing the necessary functional properties for meat and food processing procedures. If desired, additional edible acid may be added to the concentrate to bring the level of acids up to the concentration needed to match the acid:
phenol: carbonyl ratio of the original ]iquid smoke solution which is evaporatively concentrated. The addition of acid to the concentrate generally allows more dilution of the concentrate before tarry substances start to precipi-tate.
The liquid smoke concentrate, produced by the present invention, can be used in the standard liquid smoke application systems, e.g. atomization, vaporization, spraying, dipping, or direct addition to the emulsion or food product. The level of usage could be dispropor-tionately less as the concentration of the active components increases. In other words, for a 2:1 concentrate of a 10~ acidic commercial liquid smoke, one could use less than 1/2 as much of the concentrate as of the 10~ acidic liquid smoke. With the concentrate, a greater concentration of active smoke components can be applied to the meat and food products, with less water as a carrier.
One of the uniyue features of the smoke flavor concentrate of this invention is the improved browning or color-formation of meat and other food products when the concentrated smoke is applied to the external surface of the Good product and heat processed. When equal concen-trations of smoke components from commercial liquid smoke, boiled smoke concentrates, distilled smoke concentrates, or freeze concentrated smoke solutions, are applied to the external surface of meat products, the smoke concentrate of this invention yields Ein;shed products with a darker smoked color than any of the other smoke solutions. This improved brown.ing potential in a concentrated liquid smoke product will provide the processor with a) greater potential for producing darker colored smoked products, b) savings on packaging and shipping costs of liquid smoke flavor solutions, and a shortening the smoke application times for atomization and vaporization of smoke flavorings.
The hollowing examples are presented to furthef illustrate, but not restrict, the invention. All percentages in this application and examples are by weight unless otherwise stated.
With respect to the hollowing examples, the absolute browning index of a concentrate can be calculated by multiplying the starting material browning index by the percent recovery browning index times the concentration factor. Absolute acidic, phenolic and carbonyl contents are similarly calculated.
Example 1 A sample of commercial liquid smoke CharSol C-10 (Red Arrow Products Company) having 11.2% acids, 16 mg/ml of phenols, 12u4% carbonyls and a browning index of 9.4, was divided into 3 lots and concentrated in a laboratory rotary evaporator under the following conditions:
Final _atch NumberProcess Conditions Concentra-tion 1Heating hath temp. = 140F 2.6X
Vapor temp. = 117F
Vacuum, in. Hg = 26.7 2Heating bath temp. = 140F 2.0X
Vapor temp. = 117F
Vacuum, in. Hg = 26.7 3Heating bath temp. = 149F 2.0X
Vapor temp. = 125F
Vacuum, in. Hg = 26.0 Residence time in the evaporator ranged from 1.5 to 3.0 hrs. The concentrates were cooled to 70F
as soon as they were pulled from the evaporator Elask and then analyzed.
The recovery of smoke components in the concentrates was as Eollows:
a X
m Us :~ O oo a o .a' co co Jo l 1--f O l o X
O
o O
E' o O O O
Q' I' I` 1-- us (a l l En C) O ,~
The solution color of the satch 3 concentra-te was slightly darker than the concentrates Erom Batches 1 and 2. This is due to the increase in polymerization reactions of the smoke components in liquid smoke when held at the higher heating bath temperature. All three concentrates showed no evidence of polymeric precipitation or tarring in the concentrates after 6 months storage.
When diluted with water, the concentrates could be diluted back to l.lX the original concentration before dilution tar was formed and haziness was observed in the diluted smoke concentrate samples.
Analytical Procedure for Determining Browning Index of Liquid Smoke Solutions The Browning Index is a measure of the quantity of potential colox forming substances present per unit of liquid smoke flavoring.
A. Reagents 1. Phthalate bufEer, pal 5.5. Dilute the indicated quantities of the solutions to 1 liter with distilled water. 0.1 M potassium hydrogen phthalate - 500 ml. and 0.5 M NaOH 76 ml.
Background of the Invention Aqueous smoke Elavorings are routinely used as a substitute for vaporous smoking in the meat and food industry. The elimination of polycyclic aromatic hydrocarbons and particulate emissions, and the uniformity of the smoke flavor, are the major advantages that processors experience with the use of liquid smoke.
At the present time, liquid smoke solutions are applied to edible products by (1) direct addition to meat emulsions or other food products, (2) spraying with, or dipping the edible product in, liquid smoke, or (3) vaporizing or atomizing the liquid smoke and exposing the product to the smoke vapors. After applying the smoke solution, the food product is usually heated so that the smoke components react with the food product. This produces the same typical smoked flavor normally produced with the traditional vaporous smoking process.
When the commercially available aqueous smoke solutions produced by burning wood with a limited amount ox air (U.S. patents 3,106,473 and 3,873,741) are used, several problems are experienced which limit use of the liquid smoke. Some of the liquid smoke organic components are marginally soluble in aqueous solutions and tend to `.~
react and form polymeric solids in the aqueous smoke solu-tions. These solids cause problems in handling when attempt ing to atomize s~.oke solutions and, also, they create dark tar-like specs on the smoked edible products.
Another feature ox currently available aqueous smoke solutions is the limited amount oE smoke components that are absorbed into the water during the extraction process of smoke flavoring manufacture. As the concentration of liquid smoke surpasses 12~ total acidity, as acetic acid, the absorption of phenolic substances from smoke increases dramatically thus causing an imbalance of smoke components in the final product. With high phenolic contents in smoke solutions, the flavor becomes very harsh and medicinal in nature. These high phenolic smoke solutions also have poor stability and tend to lose color forming potential fairly rapidly.
Another disadvantage in the currently available methods of producing aqueous smoke flavorings is that as the concentration of smoke solution increases in the production system, the efficiency of the recovery system decreases. The cost of production of hither concentrations of aqueous smoke solutions increases disproportionately with increase in flavor and intensity.
Also, quite often currently available aqueous smoke solutions have a concentration of smoke components too low to allow for proper smoke color and flavor to develop using the s-tandard smoke application systems.
Because of the amount of water present in aqueous smoke solutions, sufficient smoke solids are not always deposited on meat products, with atomization or vaporization, to produce the desired smoke color or flavor intensity.
U.S. patent No. 4,112,133 discloses a method of eliminating the precipitated solids in aqueous smoke solutions by admixing a natural liquid smoke solution with an acidulating agent and a solubilizing agent. The process eliminates the precipitation of solids in solution but it creates an imbalance in the ratio of acid to smoke coloring components, thus reducing the browning potential of the resulting smoke solution.
Several methods of concentrating liquid smoke flavorings have been reported in the patent literature.
In U.S. patent No. 4,278,694, to Chiu, a method of concen-trating liquid smoke solutions by boiling in the presence of a water soluble alcohol solubilizing agent is described.
The resultant concentrated solution contains a higher level of some of the smoke constituents but it is greatly reduced in acid concentration. These smoke concentrates are specifically designed for application to food casings where acid causes detrimental effec-ts on the cellulose polymeric structure of the casing. however, the concentrated smoke produced by the Chiu method is not practical for external application to meat and food products due to the significant quantity of alcohol solubilizing agent present and needed in the concentrate to keep the smoke constituents in solution. Also, by concentrating the liquid smoke as described in his method, a significant reduction in color forming potential of the smoke concentrate is experienced.
U.S. patent No. 4,359,481, to Smits and rrimmermans, discloses a method of producing a liquid smoke concentrate which uses Eractional separation by step-wise cooling of vaporous smolce to obtain the concentrate. With the temperature ranyes used in condensing the smoke vapors, the majority oE the smoke flavor phenols are lost in the -two tar fractions since most of the smoke flavor phenols have boiling points near or higher than 200C. The smoke flavor phenols are the compounds normally responsible for the antioxidant and antimicrobial properties of smoke and certainly would be desired in a whole smoke flavor concentrate. In fact, Smits et al recommend adding BRA
(butylated hydroxy anisole) or BUT (butylated hydroxy toluene) to the liquid smoke concentrate for increased keepability.
Other smoke flavor concentrates produced according to U.S. patent Nos. 3,806,609; 3,903,2~7; 4,136,206; 4,154,866;
and 4,250,199 are designed primarily to concentrate the smoke flavor phenols and they do not contain the proportionate level of smoke carbonyls or browning components that are present in vaporous smoke or commercially available liquid smoke solutions. These smoke concentrates are designed as flavor additives and are not suitable for external application to meat and other food or edible products, via atomization or vaporization.
Preparation of a concentrated aqueous smoke flavoring with browning ability, flavor, antioxidant and antimicrobial properties proportionate to commercially available aqueous smoke flavorings would be highly desirable.
The advantages of such a smoke concentrate would be tha-t in its application to meat products, shorter atomization periods wound be needed, thus reducing production costs.
Less humidity would result from the atomization, which would allow shorter time to dry the products and better color formation. Also, a reduction in transportation 3~
and packaging costs per unit of flavor in the aqueous smoke flavoriny could be achieved by its being more concen-trated.
summary ox -the Invention With the present invention, aqueous smoke concen-trates, having a balanced proportion of smoke components that can provide the aforementioned advantages, are produced from commercial aqueous liquid smoke. The concentrates also have the unique characteris-tic of being essentially free of settable tars or precipitates normally experienced in commercially available liquid smoke solutions and a disproportionately high level ox active carbonyls compared to acid content which is reduced during the evaporative concentration method of the invention. When applied exter-nally to meat products, a significant improvement in color formation is observed in the final processed meat product over thaw ox commercial liquid smokes.
According to one aspect of the invention, a method of producing a concentrated aqueous smoke solution is provided which comprises evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
Also provided is a concentrated aqueous smoke solution produced by the method, and especially a concentrate containing at least about 25 mg/ml ox phenolic compounds and up to about 55 mg/ml of these compounds, wormed by increasing the phenolic compounds content 1.5 to 5 times f r~O~
that of a star ting aqueous smoke solution containing about 8 to 20 mg/ml oE phenolic compounds. A smoke flavoring concentrate having the stated phenolic concentrations will have a browning index level from about 15 to about 35 and is obtained by concentrating starting aqueous smoke solutions with browning indices of about 5 to about 13.
Practically, the browning index of the concentrate is raised at least by about 5, desirably by about 10, browning indices from the starting solution.
The invention also provides a method of imparting smoke flavor to an edible product comprising contacting an edible product wi-th a sufficient amount of a concentrated aqueous smoke solution to impart smoke flavor to the edible product; and the concentrated aqueous smoke solution being produced by evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
Even though there is a reduction in acidity by evaporative concentration according to -the described method, there is no otherwise to be expected reduction in browning index in the concentrates. While some browning ingredients boil at a temperature lower than water and would be expected to be lost by evaporation, there is nevertheless a desirable increase ln browning index of the concentrates produce by the invention, rather than a browning index decrease Furthermore, the stability of the concentrates is substantially greater than that of the starting aqueous smoke solutions. This is unexpected since it would have been expected that concentrating the smoke solution, which concentrates reactive ma-terials which could polymerize, would have led to products which settle out in increased amount and quicker Brief Description of the Drawings Figure 1 is a graph which plots the increase in concentrate viscosity with increase in concentration as measured in Brix units; and Figure 2 is a graph which plots browning index and carbonyl content of a commercial liquid smoke heated to various temperatures.
Detailed Description of the Invention Although most aqueous smoke solutions can be suitably concentrated by vacuum evaporative concentration according to the invention, it is presently considered most advantageous to use as a starting material an aqueous smoke solution obtained by contacting natural wood smoke with water in countercurrent flow as disclosed in Hollenbeck U.S. patent No. 3,106,473. Products produced according to that method are available commercially in various grades from Red Arrow Products Company, Manitowoc, Wisconsin under -the trademark CHARSOL conkaining different concentra-tions of acids, phenols and carbonyls, the key components in liquid smoke solutions.
While the starting solution need not contain any minimum amount of smoke flavors, it is generally more efficient to use an aqueous smoke solution containing active carbonyl substances giving a browning index ox at least 5, and desirably at least 7~ as the starting Lo solution. Furthermore, while there is no maximum amount of active carbonyls which can be present, it i5 generally best to employ as a starting solution, one which has active carbonyls giving a maximum browning index ox about 13, since that is the practical maximum concentration in solutions obtained by the process o the Hollenbeck U.S. patent No. 3,106,473.
No specific type of vacuum evaporator need be used to concentrate the aqueous solution. Rotary evaporators, sin91e effect and multiple effect evaporators are suitable.
Conventional evaporators now used commercially to concentrate various products can be used to concentrate aqueous smoke solutions.
The evaporative concentration process of the invention is readily effected by heating the starting aqueous smoke solution under vacuum in an evaporator to a temperature sufficiently high to vaporize water which is then removed until the product is concentrated to the desired amount. At present, it is considered optimum to employ a high vacuum, such as about 23 to 29 in. of ~g, and a vapor temperature of about 75 to 150F. Obviously, the lower the temperature of evaporation the better, but the very high vacuum necessary to evaporate at low temperature is not practical in most commercial evaporators. Temperatures above 150F are not necessary and, in general, should be avoided, especially in systems with prolonged residence time, to limit possible polymerization reactions among the smoke components during concentration.
The evaporation is continued until the desired increase in concentration is obtained. In general, the concentration is continued until the initial active carbonyl concentration of the smoke solution has been increased about 1.5 to 5 times (X), with the grea-test increase in concentration generally being effected with starting solutions having lower active carbonyl concentration. Especially useful concentrates are -those having a browning index of at least 15 such as can be produced by two-fold concentra-tion of a starting smoke solution with a 7.5 browning index. Furthermore, it is generally unnecessary to produce a concentrate having greater than a 35 browning index.
One of the important Eactors in preparing a concentrate for ease of application without dilution is the viscosity ox the solution. Figure 1 shows the increase in viscosity on concentrating a smoke solution from a s solids content of 25 Brix (CharSol C-10; Example 4) to about 68 Brix (Example 4; Run No. 2). With this concentra-tion, the viscosity increases to about 65 centipoises.
Above 65 centipoises, the solution becomes too viscous to be applied by atomization without considerable difficulty or without making special adaptations.
While the water vapor exiting the evaporator contains mainly acids and some minor levels of other compo-nents from the smoke solution, it need not be recovered and be reintroduced into the concentrate since the concen-trated smoke solution retains a very desirable balance of acids, phenols and carbon~ls for smoke Elavoring foods and imparting a desirable brown color.
Residence time in the evaporator, at the elevated temperatures, should be as short as possible to limit possible polymerization reactions. After the concentrate is discharged from the evaporator, it should be cooled to 70F as soon as possible to maintain the browning potential of the liquid smoke.
-I fr~l de rh 3~5 The liquld smoke concentrate, produced by the present invention, has a balanced proportion of smoke components that is fairly similar to that of commercial liquid smoke solutions. Accordingly, the flavor concentrates can be used in the same flavor application processes as commercial liquid smoke solutions without any major processing changes. Usage levels of the smoke concentrate, however, would be substantially less as the rate of concentration increases.
In the present invention, the recovery of the critical smoke constituents, phenols, total carbonyls, and active browning carbonyls in the concentrate is good.
The unique feature of this concentration process is the recovery of the browning carbonyls. This recovery is substantially greater than would be predicted, based on boiling points of the active carbonyls. For example, two of the important active carbonyls of wood smoke, glyoxal and pyruvaldehyde, boil at temperatures well below that o-E the boiling point of water. Yet the recovery of active carbonyls giving good browning indices in the concentrates produced by this process is unexpectedly high.
Another unique feature of this process is that in spite of a disproportionate loss of the acidic components, good solubility of the phenolic and carbonyl substances is still maintained, giving freedom from tar and providing the necessary functional properties for meat and food processing procedures. If desired, additional edible acid may be added to the concentrate to bring the level of acids up to the concentration needed to match the acid:
phenol: carbonyl ratio of the original ]iquid smoke solution which is evaporatively concentrated. The addition of acid to the concentrate generally allows more dilution of the concentrate before tarry substances start to precipi-tate.
The liquid smoke concentrate, produced by the present invention, can be used in the standard liquid smoke application systems, e.g. atomization, vaporization, spraying, dipping, or direct addition to the emulsion or food product. The level of usage could be dispropor-tionately less as the concentration of the active components increases. In other words, for a 2:1 concentrate of a 10~ acidic commercial liquid smoke, one could use less than 1/2 as much of the concentrate as of the 10~ acidic liquid smoke. With the concentrate, a greater concentration of active smoke components can be applied to the meat and food products, with less water as a carrier.
One of the uniyue features of the smoke flavor concentrate of this invention is the improved browning or color-formation of meat and other food products when the concentrated smoke is applied to the external surface of the Good product and heat processed. When equal concen-trations of smoke components from commercial liquid smoke, boiled smoke concentrates, distilled smoke concentrates, or freeze concentrated smoke solutions, are applied to the external surface of meat products, the smoke concentrate of this invention yields Ein;shed products with a darker smoked color than any of the other smoke solutions. This improved brown.ing potential in a concentrated liquid smoke product will provide the processor with a) greater potential for producing darker colored smoked products, b) savings on packaging and shipping costs of liquid smoke flavor solutions, and a shortening the smoke application times for atomization and vaporization of smoke flavorings.
The hollowing examples are presented to furthef illustrate, but not restrict, the invention. All percentages in this application and examples are by weight unless otherwise stated.
With respect to the hollowing examples, the absolute browning index of a concentrate can be calculated by multiplying the starting material browning index by the percent recovery browning index times the concentration factor. Absolute acidic, phenolic and carbonyl contents are similarly calculated.
Example 1 A sample of commercial liquid smoke CharSol C-10 (Red Arrow Products Company) having 11.2% acids, 16 mg/ml of phenols, 12u4% carbonyls and a browning index of 9.4, was divided into 3 lots and concentrated in a laboratory rotary evaporator under the following conditions:
Final _atch NumberProcess Conditions Concentra-tion 1Heating hath temp. = 140F 2.6X
Vapor temp. = 117F
Vacuum, in. Hg = 26.7 2Heating bath temp. = 140F 2.0X
Vapor temp. = 117F
Vacuum, in. Hg = 26.7 3Heating bath temp. = 149F 2.0X
Vapor temp. = 125F
Vacuum, in. Hg = 26.0 Residence time in the evaporator ranged from 1.5 to 3.0 hrs. The concentrates were cooled to 70F
as soon as they were pulled from the evaporator Elask and then analyzed.
The recovery of smoke components in the concentrates was as Eollows:
a X
m Us :~ O oo a o .a' co co Jo l 1--f O l o X
O
o O
E' o O O O
Q' I' I` 1-- us (a l l En C) O ,~
The solution color of the satch 3 concentra-te was slightly darker than the concentrates Erom Batches 1 and 2. This is due to the increase in polymerization reactions of the smoke components in liquid smoke when held at the higher heating bath temperature. All three concentrates showed no evidence of polymeric precipitation or tarring in the concentrates after 6 months storage.
When diluted with water, the concentrates could be diluted back to l.lX the original concentration before dilution tar was formed and haziness was observed in the diluted smoke concentrate samples.
Analytical Procedure for Determining Browning Index of Liquid Smoke Solutions The Browning Index is a measure of the quantity of potential colox forming substances present per unit of liquid smoke flavoring.
A. Reagents 1. Phthalate bufEer, pal 5.5. Dilute the indicated quantities of the solutions to 1 liter with distilled water. 0.1 M potassium hydrogen phthalate - 500 ml. and 0.5 M NaOH 76 ml.
2. 1% Glycine buffer solution. Dissolve 1 9. of glycine in 100 ml. of the pH 5.5 phthalate bufEer.
Prepare fresh weekly, store at 0C.
B. Procedure 1. One pair of 20 x 150 mm. test tubes is needed for each sample to be analyzed. Pipette 10 ml.
of the phthalate buffer (for unreacted control) ~L~2'~ 3~
into one tube of each pair of test tubes. Pipette 10 ml. of glycine buffer solution lnto the other tube oE each pair.
2. Cap the tubes with marbles and temper khe tubes in a boiling water bath for 5 minutes.
Prepare fresh weekly, store at 0C.
B. Procedure 1. One pair of 20 x 150 mm. test tubes is needed for each sample to be analyzed. Pipette 10 ml.
of the phthalate buffer (for unreacted control) ~L~2'~ 3~
into one tube of each pair of test tubes. Pipette 10 ml. of glycine buffer solution lnto the other tube oE each pair.
2. Cap the tubes with marbles and temper khe tubes in a boiling water bath for 5 minutes.
3. Then add 1.0 ml. of aqueous smoke solution (diluted 1:50 for CharSol C-10 and diluted 1:25 Eor CharSol C-6 and CharSol C-8.5) to both oE the tubes of each pair, one containing buffer only (unreacted control) and the other containing glycine solution (reaction tube.) Add 1.0 ml. of distilled water to a tube containing glycine solution to serve as a reagent blank.
4. Allow the color reac-tion to proceed at 100C
for exactly 20 minutes, after which the tubes are removed from the boiling water bath and cooled in an ice bath for 2 minutes.
for exactly 20 minutes, after which the tubes are removed from the boiling water bath and cooled in an ice bath for 2 minutes.
5. Determine the optical density of both the reacted samples and the unreacted controls at a wave length of 400 nm. Read against the glycine-water blank set at optical density of 0. (cuvettes -1/2" diameter, or equivalent).
C. Calculations - Browning Index of _harSol . _ Optical density (O.D.) reading of the unreacted control is substracted from the O.D. of the reacted sample to obtain the net increase in the optical density due to the color formed by -the browning reaction.
A correction must be made for non-linearity in the curve of the unreacted samples by adding the interceptr .14, to the O.D. dlifference. Browning index is deter-mined by the formula:
Brown ing i nd e x = (O . D . r . D . un factor x .65 Example 2 A commercial liquid smoke, CharSol C-10 containing 11.2% acids, 17.4 mg/ml phenols, 13.4~ carbonyls and having a browning index of 9.4, was used to produce smoke conc~n-trates by boiling and by the present invention using vacuum evaporation. A 2.02 X and 4.24 X concentrate was produced by boiling at atmospheric conditions, 30.6 in. Hg. A
2.5 X concentrate was then produced according to the present invention using a vacuum of 28.8 in. Hg and a vapor tempera-ture of 107F. Recovery of smoke components in the concen-trates was as follows:
Recover Browning Concentrate Acids Phenols Carbonyls Index 4.24 X (boiled) 38.3 76.5 49.3 47.3 2.02 X (boiled) 53.4 91.8 62.6 52.3 2.5 X (high vacuum, 49.8 90O3 79.1 80.2 low temp.) The recovery of smoke co~lponen-ts in the boiled concentrates is significantly less than in the concentrates produced by vacuum evaporation. The recoveries of the carbonyls and the browning index of the boiled concentrate indicate a significant loss in the proportion of smoke flavor phenols. This leads to concentrates with poor color-Eorming potential when used on surface applications for making smoked meats.
With the present invention, a concentrate is obtained by vacuum evalporation that has good recovery D
of carbonyls and a hign browning index so as Jo yield a smoke flavor concentrate with a balanced proportion ox active smoke components contributing to the flavor and color of smoked meats and other foods.
The concentrates produced were also evaluated for dilution tar by diluting the concentrates to 11~ solids, as determined with a refractometer. The amount of tar formed on dilution was determined gravimetrically and compared against that of the parent liquid smoke Increase in Concentrate Dilution Tar 4.24 X (boiled) 171 2.02 X (boiled) 137 2.5 X (high vacuum, 38 low temp.) Concentrates produced by boiling at atmospheric conditions show a signi-ficant increase in the quantity of tar formed on dilution. This is due to the fact that the high temperatures, used for concentrating, accelerate condensation reactions between the smoke components and the excessive loss of acids by boiling allow Eor reduced solubility of the smoke components in the concentrate.
With the present invention, the high vacuum and lower vapor temperatures allow for better recovery of smoke components and less chance for condensation reactions to take place between smoke components.
Example 3 Three commercial liquid smoke solutions having the following compositions:
ox A B C
Acid (~) 5.7 8.0 11.9 Phenols (mg/ml) 8.1 11.4 19.4 Carbonyls (~) 6.7 9.5 13.8 frowning Index 4.5 7.0 9.8 were concentrated on a laboratory rotary evaporator at a vacuum of 27 in. of Hg and a heating bath temperature of 122F. The vapor temperature during concentration was 115F. Samples were concentrated until the browning index of the concentrates was over 20. The concentrates were then cooled to 70~F and analyzed for acids and browning index. The concentrates were then diluted with water to produce a final smoke solution with 11% solids, as determined with a refractometer. The amount of tar formed on dilution was determined gravimetrically. Analyses oE the concentrates were as follows InitialAcids inBrowning Index dilution AcidsConcentrateof Concentrate Tar A.5.7% 15.7% 20.7 .58%
B.8.0 16.7 22.8 1.18 C.11.9 19.2 21.5 3.71 The results show that by using less concentrated liquid smoke solutions to produce the concentrate, a concen-trate with lower dilution tar is produced.
Example 4 A commercial liquid smoke, CharSol C-10 containing 12% acids, 15.2 mg/ml phenols, 12.5% carbonyls and having a browning index of 10.4, was concentrated on a Niro Atomizer a O
triple-effec-t, falling-film evaporator having a 1,000 lb./hr. evaporation capacity. In an a-ttempt to retain as much of the volatile material as possible, the evaporator was run in reverse flow. The feed material entered the evaporator at only 2-3F above the boiling point so the amount of "flash" would be reduced. Two runs were made under the following conditions:
Vapor Vacuum Final Run No.Temperature(in. Hg) Concentration 1 109F 27.25 1.98X
2 112F 27.25 3.18X
The residence time of the liquid smoke in the evaporator was less than 2 minutes. Upon discharge from the evaporator, the concentrate was cooled to 70F and analyzed. Recovery of the smoke components in the concentrate was as follows:
% Recovery Browning Run No. Concentration Acids Phenols Carbon~ls Index 1 1.98X 67.2 93.2 84.6 90.9 2 3.18X ~3.7 99.5 83.0 8~.3 The concentrates remained tar-free on storage at 70F.
Example 5 The same commercial liquid smoke, CharSol C-10, of Example 4 was concentrated on a Centritherm CT-lB evapo-rator. The liquid smoke was fed into the unit at 70F
and had a residence time in the evaporator of less than k 1 second. The evaporator was operated at a vacuum of 27.5-28.8 in. Hg and the product temperature of the concen-rate coming out of the unit was 105-108F. The concentrate was then cooled to 70F and analyzed. Recovery of smoke components in the concentrate was as follows:
% Recovery Browning Sample Concentration Acids Phenols Carbonyls Index 1 1.7x 63.1 95.6 80.1 83.9 2 2.~ 26.5 68.8 60.7 71.3 The smoke flavor concentrates remained tae-free during storage.
Example 6 To a sample of smoke concentrate from Batch No. 2 in Example 1, 7~ (w/v) glacial acetic acid was added to bring the acid level up to the level of 2 X the acid concentration of the original C-10. This simulated a 100% recovery of acetic acid in the concentrate.
With the addition of the acetic acid, the concen-trate could be diluted back to O.9X the original concentra-tion of liquid smoke before dilution tar was observed.
Accordingly, by adding edible acid to bring the acid concen-tration up to that oE the concentration factor times the original acids in the starting liquid smoke, one can produce a concentrate that can be diluted back to its starting concentration without formation of dilution tar.
Example 7 A commercial aqueous liquid smoke, CharSol C-10 having 11.2~ acids, 16 mg/ml phenols, 12.4~ carbonyls and a browning index of 9.4, was concentrated on a laboratory rotary evaporator to two concentrations, 2.0 X and 3.75 X
products. The concentration was carried out at a vacuum of 27.0 in. Hg and a vapor temperature of 115F.
Samples of the concentrates and liquid smoke were stored at 40C. They were evaluated, periodically, for the presence of tar that had precipitated with storage.
_ % (W/V) Storage Tar Storage TimeCharSol C-102.0 X Concentrate 3.75 X Concentrate 2 Weeks.52 0 0 1 Month1.02 0 0 2 Months 1.70 0 0 3 Months 2.28 0 0 These results show the improved storage stability of the concentrate over that of the parent liquid smoke solution.
Example 8 The 1.98X natural smoke concentrate as produced in Example 4 was applied to skinless wieners and smoked sausage at a rate of 2 oz. per cwt. with a commercial atomization system. Another lot of the skinless wieners and smoked sausage was atomized with 4 oz. per cwt. of commercial liquid smoke, CharSol C-10. Both lots were then heat processed with the same commercial schedule.
3~
The Einished smoked products were cooled, aged, and evaluated for general appearance. A tralned panel of five rated the sausages and wieners smoked with the 1.9~X concentrate significantly browner in color than those treated with the standard commercial liquid smoke.
Example 9 In a four cage smokehouse containing 32 lbs.
of beef and pork wieners, 64 oz. of a commercial liquid smoke, CharSol C-10, was atomized. This was repeated with 32 oz. of the 1.98X concentrate as prepared in Example 4.
The products were then processed out with the standard commercial schedule. The wieners were shower-cooled, chilled, packaged, and evaluated for intensity of brown color development 2~ hours later. A trained panel of seven evaluated both smoked wieners and found the concentrate treated wieners to be significantly darker than the regular liquid smoke treated wieners. The concentrate treated wieners were also darker than natural vaporous smoked wieners produced by the commercial plant using the same processing schedule.
Example 10 A sample of commercial liquid smoke, CharSol C-10 containing 11.2% acids, 17.4 mg/ml phenols and 13.4%
carbonyls and having a browning index of 9.4, was divided into five lots and held at various process temperatures for 2 hours. This time period was to simulate the average residence time of product in the small laboratory evaporator used in Examples 1, 2, 3 and 7. The heat treated liquid smokes were then analyzed for carbonyls and browning index.
The results are shown in Figure 2.
The results show the heat lability of liquid smoke solutions and the critical product temperatures required in the evaporations to retain a good concentration of the smoke carbonyls responsible for color formation in smoked foods. IE the product is held in the evaporator as long as 2 hours, temperatures above 150F are detrimental to the quality of process liquid smoke solutions. In commercial evaporators, the residence time of the solution is generally only a few minutes, so temperatures higher than 150F would not be nearly as detrimental to the product as indicated with a 2 hour residence time. To maintain evaporation temperatures below 150~, a vacuum of 23 inches ox Hg or more is needed.
The foregoing detailed description has been given for clearness oE understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.
- ~3 -
C. Calculations - Browning Index of _harSol . _ Optical density (O.D.) reading of the unreacted control is substracted from the O.D. of the reacted sample to obtain the net increase in the optical density due to the color formed by -the browning reaction.
A correction must be made for non-linearity in the curve of the unreacted samples by adding the interceptr .14, to the O.D. dlifference. Browning index is deter-mined by the formula:
Brown ing i nd e x = (O . D . r . D . un factor x .65 Example 2 A commercial liquid smoke, CharSol C-10 containing 11.2% acids, 17.4 mg/ml phenols, 13.4~ carbonyls and having a browning index of 9.4, was used to produce smoke conc~n-trates by boiling and by the present invention using vacuum evaporation. A 2.02 X and 4.24 X concentrate was produced by boiling at atmospheric conditions, 30.6 in. Hg. A
2.5 X concentrate was then produced according to the present invention using a vacuum of 28.8 in. Hg and a vapor tempera-ture of 107F. Recovery of smoke components in the concen-trates was as follows:
Recover Browning Concentrate Acids Phenols Carbonyls Index 4.24 X (boiled) 38.3 76.5 49.3 47.3 2.02 X (boiled) 53.4 91.8 62.6 52.3 2.5 X (high vacuum, 49.8 90O3 79.1 80.2 low temp.) The recovery of smoke co~lponen-ts in the boiled concentrates is significantly less than in the concentrates produced by vacuum evaporation. The recoveries of the carbonyls and the browning index of the boiled concentrate indicate a significant loss in the proportion of smoke flavor phenols. This leads to concentrates with poor color-Eorming potential when used on surface applications for making smoked meats.
With the present invention, a concentrate is obtained by vacuum evalporation that has good recovery D
of carbonyls and a hign browning index so as Jo yield a smoke flavor concentrate with a balanced proportion ox active smoke components contributing to the flavor and color of smoked meats and other foods.
The concentrates produced were also evaluated for dilution tar by diluting the concentrates to 11~ solids, as determined with a refractometer. The amount of tar formed on dilution was determined gravimetrically and compared against that of the parent liquid smoke Increase in Concentrate Dilution Tar 4.24 X (boiled) 171 2.02 X (boiled) 137 2.5 X (high vacuum, 38 low temp.) Concentrates produced by boiling at atmospheric conditions show a signi-ficant increase in the quantity of tar formed on dilution. This is due to the fact that the high temperatures, used for concentrating, accelerate condensation reactions between the smoke components and the excessive loss of acids by boiling allow Eor reduced solubility of the smoke components in the concentrate.
With the present invention, the high vacuum and lower vapor temperatures allow for better recovery of smoke components and less chance for condensation reactions to take place between smoke components.
Example 3 Three commercial liquid smoke solutions having the following compositions:
ox A B C
Acid (~) 5.7 8.0 11.9 Phenols (mg/ml) 8.1 11.4 19.4 Carbonyls (~) 6.7 9.5 13.8 frowning Index 4.5 7.0 9.8 were concentrated on a laboratory rotary evaporator at a vacuum of 27 in. of Hg and a heating bath temperature of 122F. The vapor temperature during concentration was 115F. Samples were concentrated until the browning index of the concentrates was over 20. The concentrates were then cooled to 70~F and analyzed for acids and browning index. The concentrates were then diluted with water to produce a final smoke solution with 11% solids, as determined with a refractometer. The amount of tar formed on dilution was determined gravimetrically. Analyses oE the concentrates were as follows InitialAcids inBrowning Index dilution AcidsConcentrateof Concentrate Tar A.5.7% 15.7% 20.7 .58%
B.8.0 16.7 22.8 1.18 C.11.9 19.2 21.5 3.71 The results show that by using less concentrated liquid smoke solutions to produce the concentrate, a concen-trate with lower dilution tar is produced.
Example 4 A commercial liquid smoke, CharSol C-10 containing 12% acids, 15.2 mg/ml phenols, 12.5% carbonyls and having a browning index of 10.4, was concentrated on a Niro Atomizer a O
triple-effec-t, falling-film evaporator having a 1,000 lb./hr. evaporation capacity. In an a-ttempt to retain as much of the volatile material as possible, the evaporator was run in reverse flow. The feed material entered the evaporator at only 2-3F above the boiling point so the amount of "flash" would be reduced. Two runs were made under the following conditions:
Vapor Vacuum Final Run No.Temperature(in. Hg) Concentration 1 109F 27.25 1.98X
2 112F 27.25 3.18X
The residence time of the liquid smoke in the evaporator was less than 2 minutes. Upon discharge from the evaporator, the concentrate was cooled to 70F and analyzed. Recovery of the smoke components in the concentrate was as follows:
% Recovery Browning Run No. Concentration Acids Phenols Carbon~ls Index 1 1.98X 67.2 93.2 84.6 90.9 2 3.18X ~3.7 99.5 83.0 8~.3 The concentrates remained tar-free on storage at 70F.
Example 5 The same commercial liquid smoke, CharSol C-10, of Example 4 was concentrated on a Centritherm CT-lB evapo-rator. The liquid smoke was fed into the unit at 70F
and had a residence time in the evaporator of less than k 1 second. The evaporator was operated at a vacuum of 27.5-28.8 in. Hg and the product temperature of the concen-rate coming out of the unit was 105-108F. The concentrate was then cooled to 70F and analyzed. Recovery of smoke components in the concentrate was as follows:
% Recovery Browning Sample Concentration Acids Phenols Carbonyls Index 1 1.7x 63.1 95.6 80.1 83.9 2 2.~ 26.5 68.8 60.7 71.3 The smoke flavor concentrates remained tae-free during storage.
Example 6 To a sample of smoke concentrate from Batch No. 2 in Example 1, 7~ (w/v) glacial acetic acid was added to bring the acid level up to the level of 2 X the acid concentration of the original C-10. This simulated a 100% recovery of acetic acid in the concentrate.
With the addition of the acetic acid, the concen-trate could be diluted back to O.9X the original concentra-tion of liquid smoke before dilution tar was observed.
Accordingly, by adding edible acid to bring the acid concen-tration up to that oE the concentration factor times the original acids in the starting liquid smoke, one can produce a concentrate that can be diluted back to its starting concentration without formation of dilution tar.
Example 7 A commercial aqueous liquid smoke, CharSol C-10 having 11.2~ acids, 16 mg/ml phenols, 12.4~ carbonyls and a browning index of 9.4, was concentrated on a laboratory rotary evaporator to two concentrations, 2.0 X and 3.75 X
products. The concentration was carried out at a vacuum of 27.0 in. Hg and a vapor temperature of 115F.
Samples of the concentrates and liquid smoke were stored at 40C. They were evaluated, periodically, for the presence of tar that had precipitated with storage.
_ % (W/V) Storage Tar Storage TimeCharSol C-102.0 X Concentrate 3.75 X Concentrate 2 Weeks.52 0 0 1 Month1.02 0 0 2 Months 1.70 0 0 3 Months 2.28 0 0 These results show the improved storage stability of the concentrate over that of the parent liquid smoke solution.
Example 8 The 1.98X natural smoke concentrate as produced in Example 4 was applied to skinless wieners and smoked sausage at a rate of 2 oz. per cwt. with a commercial atomization system. Another lot of the skinless wieners and smoked sausage was atomized with 4 oz. per cwt. of commercial liquid smoke, CharSol C-10. Both lots were then heat processed with the same commercial schedule.
3~
The Einished smoked products were cooled, aged, and evaluated for general appearance. A tralned panel of five rated the sausages and wieners smoked with the 1.9~X concentrate significantly browner in color than those treated with the standard commercial liquid smoke.
Example 9 In a four cage smokehouse containing 32 lbs.
of beef and pork wieners, 64 oz. of a commercial liquid smoke, CharSol C-10, was atomized. This was repeated with 32 oz. of the 1.98X concentrate as prepared in Example 4.
The products were then processed out with the standard commercial schedule. The wieners were shower-cooled, chilled, packaged, and evaluated for intensity of brown color development 2~ hours later. A trained panel of seven evaluated both smoked wieners and found the concentrate treated wieners to be significantly darker than the regular liquid smoke treated wieners. The concentrate treated wieners were also darker than natural vaporous smoked wieners produced by the commercial plant using the same processing schedule.
Example 10 A sample of commercial liquid smoke, CharSol C-10 containing 11.2% acids, 17.4 mg/ml phenols and 13.4%
carbonyls and having a browning index of 9.4, was divided into five lots and held at various process temperatures for 2 hours. This time period was to simulate the average residence time of product in the small laboratory evaporator used in Examples 1, 2, 3 and 7. The heat treated liquid smokes were then analyzed for carbonyls and browning index.
The results are shown in Figure 2.
The results show the heat lability of liquid smoke solutions and the critical product temperatures required in the evaporations to retain a good concentration of the smoke carbonyls responsible for color formation in smoked foods. IE the product is held in the evaporator as long as 2 hours, temperatures above 150F are detrimental to the quality of process liquid smoke solutions. In commercial evaporators, the residence time of the solution is generally only a few minutes, so temperatures higher than 150F would not be nearly as detrimental to the product as indicated with a 2 hour residence time. To maintain evaporation temperatures below 150~, a vacuum of 23 inches ox Hg or more is needed.
The foregoing detailed description has been given for clearness oE understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.
- ~3 -
Claims (18)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of producing a concentrated aqueous smoke solution which comprises evaporating an aqueous smoke solution under a vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
2. A method according to claim 1 in which the aqueous smoke solution starting material contains acids and the vacuum evaporation raises the amount of active carbonyls at least about 1.5 times in the concentrated aqueous smoke solution.
3. A method according to claim 1 in which the aqueous smoke solution starting material contains active carbonyls to give a browning index of about 5 to 13 and the vacuum evaporation raises the amount of active carbonyls to about 1.5 to 5 times in the concentrated aqueous smoke solution.
4. A method according to claim 1 in which the high vacuum is about 23 to 29 in. of Hg and the evaporation temperature is about 75°F to 150°F.
5. A method according to claim 4 in which the concentrated aqueous smoke solution is rapidly cooled to a maximum of 70°F.
6. A method according to claim 1 in which an edible acid is added to the concentrated aqueous smoke solution.
7. A method according to claim 6 in which the edible acid is acetic acid.
8. A method of imparting smoke flavor to an edible product comprising:
contacting an edible product with a sufficient amount of a concentrated aqueous smoke solution to impart smoke flavor to the edible product;
the concentrated aqueous smoke solution being produced by evaporating an aqueous smoke solution under a high vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
contacting an edible product with a sufficient amount of a concentrated aqueous smoke solution to impart smoke flavor to the edible product;
the concentrated aqueous smoke solution being produced by evaporating an aqueous smoke solution under a high vacuum at a temperature sufficiently high to produce water vapor, removing water vapor, and continuing the vacuum evaporation with water vapor removal until enough water is removed to produce a concentrated aqueous smoke solution.
9. A method according to claim 8 in which the concentrated aqueous smoke solution is produced by using a high vacuum of about 23 to 29 in. of Hg and an evaporation temperature of about 75°F to 150°F.
10. A method according to claim 9 in which the concentrated aqueous smoke solution contains active carbonyls to give a browning index of about 15 and up to about 35, and is produced by vacuum evaporation to increase the concentration about 1.5 to 5 times that of a starting aqueous smoke solution containing active carbonyls giving browning indices of about 5 to 13.
11. A method according to claim 8 in which the edible product is a meat product.
12. A method according to claim 11 in which the meat product is a sausage.
13. A concentrated aqueous smoke solution having a desirable balance of acids, phenols and carbonyls for smoke flavouring foods and imparting a desirable brown color, the solution having a browning index of at least about 15 and up to about 35 due to active browning carbonyls therein, produced by evaporation under vacuum.
14. A concentrated aqueous smoke solution according to claim 15 at least about 25 mg/ml, and up to about 55 mg/ml, of phenolic compounds.
15. A concentrated aqueous smoke solution accordng to claim 14 in which the starting material contains about 8 to 20 mg/ml of phenolic compounds.
16. A concentrated aqueous smoke solution having a desirable balance of acids, phenols and carbonyls for smoke flavoring foods and imparting a desirable brown color, the solution having a browning index of at least about 15 and up to about 35 due to active browning carbonyls therein; and, the concentrated aqueous smoke solution being dilutable with water to about 11% solids with a maximum of 3.7% tar formation.
17. A concentrated aqueous smoke solution having a desirable balance of acids, phenols and carbonyls for smoke flavoring foods and imparting a desirable brown color, the solution having a browning index of at least about 15 and up to about 35 due to active browning carbonyls therein; the concentrated aqueous smoke solution being produced from an aqueous smoke solution starting material having active carbonyls which give a browning index of about 5 to 13 and which by vacuum evaporation yields the concentrated solution; and the concentrated aqueous smoke solution being dilutable with water to about 11% solids with a maximum of 3.7% tar formation.
18. A concentrated aqueous smoke solution having a desirable balance of acids, phenols and carbonyls for smoke flavoring foods and imparting a desirable brown color, the solution having a browning index of at least 15 and up to about 35 due to active browning carbonyls therein; the concentrated aqueous smoke solution being produced from an aqueous smoke solution starting material having active carbonyls which give a browning index of about 5 to 13 and which by vacuum evaporation at a high vacuum of about 23 to 29 in. of Hg and an evaporation temperature of about 75°F to 150°F yields the concentrated solution; and with the concentrated aqueous smoke solution being dilutable with water to about 11% solids with a maximum of 3.7% tar formation.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US56923184A | 1984-01-09 | 1984-01-09 | |
| US569,231 | 1984-01-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1242106A true CA1242106A (en) | 1988-09-20 |
Family
ID=24274601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000460368A Expired CA1242106A (en) | 1984-01-09 | 1984-08-03 | Smoke flavor concentrate |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1242106A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0494966A1 (en) * | 1989-10-04 | 1992-07-22 | Red Arrow Prod Co | High browning liquid smoke composition and method of making a high browning liquid smoke composition. |
| EP0656753A4 (en) * | 1991-08-12 | 1995-02-08 | Red Arrow Prod Co | Impregnated casing and method of making the same. |
| CN110463893A (en) * | 2019-09-11 | 2019-11-19 | 中国热带农业科学院香料饮料研究所 | A kind of pepper smoke solution and preparation method thereof |
| CN115884687A (en) * | 2020-04-03 | 2023-03-31 | 凯瑞卢森堡有限责任公司 | Natural flavoring agent and natural smoke flavoring agent for enhancing function of buffering organic acid and preparation method thereof |
-
1984
- 1984-08-03 CA CA000460368A patent/CA1242106A/en not_active Expired
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0494966A1 (en) * | 1989-10-04 | 1992-07-22 | Red Arrow Prod Co | High browning liquid smoke composition and method of making a high browning liquid smoke composition. |
| EP0494966A4 (en) * | 1989-10-04 | 1992-11-04 | Red Arrow Products Co. Inc | High browning liquid smoke composition and method of making a high browning liquid smoke composition |
| EP0656753A4 (en) * | 1991-08-12 | 1995-02-08 | Red Arrow Prod Co | Impregnated casing and method of making the same. |
| EP0656753A1 (en) * | 1991-08-12 | 1995-06-14 | Red Arrow Products Co. Inc | Impregnated casing and method of making the same |
| CN110463893A (en) * | 2019-09-11 | 2019-11-19 | 中国热带农业科学院香料饮料研究所 | A kind of pepper smoke solution and preparation method thereof |
| CN110463893B (en) * | 2019-09-11 | 2022-04-22 | 中国热带农业科学院香料饮料研究所 | Pepper smoking liquid and preparation method thereof |
| CN115884687A (en) * | 2020-04-03 | 2023-03-31 | 凯瑞卢森堡有限责任公司 | Natural flavoring agent and natural smoke flavoring agent for enhancing function of buffering organic acid and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| SU897098A3 (en) | Method of producing smoking liquid | |
| CA2105658C (en) | Flavoring and browning materials by pyrolysis of sugars and starches | |
| US3873741A (en) | Air regulation in the pyrolysis of wood to produce liquid smoke for the treatment of food products | |
| US5270067A (en) | Impregnated casing and method of making the same | |
| US5135770A (en) | High browning liquid smoke composition and method of making a high browning liquid smoke composition | |
| FI77962B (en) | CONCENTRATIONS FOR EXPLORATORY FRAMEWORK FRAON VILKEN TJAERAN AVLAEGSNATS. | |
| US4956194A (en) | Method for accelerating the aging of distillates | |
| CA1242106A (en) | Smoke flavor concentrate | |
| US4604309A (en) | Food casing which will transfer a smoke color to food encased therein and extracted natural liquid smoke colorant for use therewith | |
| US4883676A (en) | Method of forming liquid smoke | |
| US5039537A (en) | High browning liquid smoke composition and method of making a high browning liquid smoke composition | |
| US6214395B1 (en) | Liquid smoke browning agent solution | |
| CA1193131A (en) | Freeze concentration of aqueous wood smoke flavor solutions and use thereof | |
| Ikins et al. | N-Nitrosamine formation in fried bacon processed with liquid smoke preparations | |
| US6261623B1 (en) | Method for making a liquid smoke coloring agent solution | |
| EP0121924A2 (en) | Tar-depleted liquid smoke solutions and method | |
| US4751097A (en) | Method of producing liquid smoke with enhanced staining capacity | |
| CN1070318A (en) | Emulsified taste-modifier composition and manufacture method thereof | |
| EP0859555A1 (en) | Method of removing hydrocarbons from liquid smoke and flavoring compositions | |
| CA1183390A (en) | Liquid smoke with enhanced staining capacity | |
| CA1227690A (en) | Tar-depleted liquid smoke solutions and methods | |
| WO1991014379A1 (en) | Process for producing hydroxyacetaldehyde | |
| Lantz et al. | Flavor effects of different woods on whitefish smoked in a kiln with controlled temperature, humidity, and air velocity | |
| CN116711766A (en) | Method for preparing smoke liquid from cyclobalanopsis glauca and application of smoke liquid | |
| AU592184B2 (en) | Liquid smoke |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |