Paper support for confectionery products and method of making same

Abstract

A paper stick or support for confectionery products, in particular lollipops, is described, characterized by having optimal adhesion properties to edible parts and a high degree of compatibility with high-speed production lines. Also described is a method of making said paper rod or support, comprising a heat treatment stage before or after a stage of applying a lubricating substance.

Description

[0001] The invention relates to a paper support in the form of a rod or stick, a process for its preparation and its use in the production of lollipops. Background Art

[0002] Sticks made from paper material are known, see for example US 2218525 which describes a method of making sticks or rods from rolled paper (or similar material) which are suitable for use in confectionery products and have the required flexibility and resistance to breakage.

[0003] The paper material used to form the sticks described in US 2218525 ensures that the edible portion is optimally fixed by the paper pores, but such pores may generate greater friction during the production process, causing some steps of the continuous process to slow down.

[0004] In practice it is common to distribute a lubricating substance on the surface of such a rod, thereby allowing better machinability and thus speeding up the production process of the rod itself and possibly of related products.

[0005] Several methods are already known, such as the one described in US20220314570, in which, in addition to a method for producing paper sticks for different uses, possible treatments are generally described which, together with other process stages, are suitable for solving the technical problems of accelerating large-scale production while maintaining the possibility of obtaining a wide variety of end products depending on the intended use.

[0006] Although it is mentioned that the method can be used to produce sticks for lollipops, there is no mention of the problem of potential detachment of the edible portion as it is fixed, at the stage immediately after the product is formed and before the edible mass has cooled.

[0007] In cases where the rods fail to ensure adequate heat setting as measured by appropriate dynamic metrology methods, the product is deemed not to meet the expected quality standards and therefore non-compliant.

[0008] It is also known to note that the application of certain lubricating substances to the surface of sticks is widely used to improve the workability / machinability of the sticks, in such a way that the adhesion of the edible substance to the stick is lower than to an untreated paper stick.

[0009] Therefore, there is a need to make available paper sticks which ensure optimal adhesion to the edible portion and which are compatible with the high speed production lines typically used to produce lollipops and related products. Detailed Description of the Invention

[0011] The solution of the invention consists in preparing a stick of paper and resin, which is coated with wax as a lubricating substance and has an outer surface characterized by a predetermined roughness and / or a predetermined surface tension.

[0012] Therefore, a first subject of the present invention is a paper and resin stick to which at least one wax is applied as a lubricating substance, characterized in that the roughness measured by confocal microscopy with chromatic aberration is >4.1 μm, preferably in the range of 4.3 μm to 5 μm, or characterized in that the contact angle measured by the dynamic Wilhelmy method is in the range of 60° to 82° and has a moisture content of not more than 6%.

[0013] The roughness value is expressed as the standard deviation of the surface height and is determined by confocal microscopy with chromatic aberration, for example using an FRT MicroProf® instrument.

[0014] More particularly, an average scale value of 0.0624 to 2 mm is considered. Conventional roughness values ​​for paper are in the range of 3.8 to 4.1 μm.

[0015] The second subject of the present invention is a method for producing the stick, which comprises applying wax as a lubricating substance to a prefabricated paper and resin stick and drying it at a temperature above 40°C for a period of 1 minute to 72 hours, but not necessarily in this order. The drying is preferably carried out at a temperature of 70 to 150°C, until the moisture content is no more than 6% by weight of the stick. In particular, the moisture content is preferably 3.5 to 5.5% by weight of the stick.

[0016] In addition to the defined roughness, the surface of the rod can also be characterized by its surface tension, which is determined using the contact angle technique.

[0017] Surface tension is considered a measure of the rod's surface polarity, influenced by the ratio between the lubricant (non-polar) and cellulose (polar) when exposed on the surface. Therefore, the contact angle is a measure of the rod's surface tension and is an indirect result of the heat treatment described above, which allows the lubricant to penetrate the cellulose matrix, exposing more fibers, thereby increasing polarity and wettability, resulting in a lower contact angle. The increased polarity promotes interaction with the polar sugars of the edible portion, increasing adhesion, which is also expressed as detachment force and can be measured according to the method described below.

[0018] More particularly, the rods of the present invention are characterized by a contact angle, measured according to the dynamic Wilhelmy method, during a first immersion in a range of 60° to 82°, preferably 67° to 79°, and / or a contact angle during a second immersion of <20°, preferably <10°. Rods made according to the prior art are characterized by a higher contact angle during the first immersion.

[0019] The contact angle is measured according to the dynamic Wilhelmy method, wherein immersion in distilled or deionized water, such as Milli-Q®, is performed using known instruments, such as or Tensiometer, or Sigma 700 / 701 Attension® tensiometer, or DataPhysics DCAT 15. Water absorption can also be measured by measuring the difference in weight between the rod before and after soaking. The rods of the present invention are characterized in that after the second soak, the water absorption per rod is >0.040 g, preferably >0.045 g. Alternatively, the rods of the present invention are characterized in that after the second soak, the water absorption is >10.7 wt %, preferably >12 wt %.

[0020] Therefore, it was found that the amount of surface wax, the residual moisture content in the stick, the thermal release force of the stick at the edible portion as described below, the contact angle, and the water absorption are interrelated. Compared with sticks prepared according to the prior art, the sticks subjected to the drying process as described above have less wax on the surface, less moisture, a smaller contact angle, greater water absorption, and a higher thermal release force at the edible portion (Example 9).

[0021] Another subject of the invention relates to the use of a stick having the above characteristics and obtained by the method described in the method for producing lollipops, wherein the stick is immersed in a molten mass constituting the edible part of the confectionery product.

[0022] The paper that can be used in the present invention is any type of paper suitable for the food industry. Preferably, a paper having a basis weight of about 60 to 90 g / m 2 and paper having a thickness of 70 to 120 microns, comprising hardwood (HW) fibers or softwood (SW) fibers having a length typically of 0.5 to 5 mm.

[0023] Available resins can be classified into three broad groups: urea-formaldehyde resins, melamine-formaldehyde resins, and polyamidoamine-epichlorohydrin resins. Other options include vinyl glues such as polyvinyl acetate. Other options include polyethyleneimine, dialdehyde starch, polyacrylamide with glyoxal substituents (GPAM), alkyl ketene dimer (AKD), and alkenyl succinic anhydride (ASA).

[0024] Polyamide epichlorohydrin (also known as PAE) is a cationic resin belonging to the large group of polyamidoamine-epichlorohydrin resins; several types are commercially available, for example under the trade name Kimene®.

[0025] The resin is part of a paper roll that has been pre-treated with water. This water treatment is necessary to ensure that the wound paper remains closed and does not unwind. Water can be added in multiple steps. In one method, most of the winding process can be dry, with only the final part of the winding process involving the addition of water drops. In an alternative method, water is added before the paper is wound, so the entire winding operation is performed with wet paper. The resin can be added simultaneously with the water in the form of an aqueous emulsion, as is the case with PAE or vinyl acetate emulsions. A drying stage is necessary to evaporate excess water and to help the resin harden and bond to the paper fibers (crosslinking), optionally through covalent bonds, as is the case with PAE.

[0026] The wax, as a lubricating substance, must be present on the outer surface of the sticks, the purpose of which is to promote sliding between the sticks during the step of loading the machine for producing lollipops, as well as on the metal or other material parts of the machine itself.

[0027] The waxes that can be used in the process of the invention can be of any compatible type, in particular carnauba wax, beeswax, polyolefin waxes. These waxes are applied by conventional methods. The waxes can be used as mixtures with one another or carried in more complex formulations containing, for example, oils and / or additives.

[0028] Heat treatment of the paper sticks can be performed before or after wax application. If heat treatment is performed before wax application, heating is performed during the paper stick production process. Drying is already performed during paper stick production to remove some of the water (typically along with the resin) introduced from previous production steps. However, in the present method, the temperature is raised to >60°C, preferably >90°C, and even more preferably to approximately 100°C. Drying temperatures are preferably <180°C; higher temperatures can damage the paper and cause yellowing. The sticks are dried in an efficient system, such as a drying tunnel or screw conveyor, where they are exposed to heat and / or forced air in a very efficient manner. When the air temperature is adjusted as described, it takes 1 to 30 minutes, preferably 5 to 15 minutes, to heat and dry them and accelerate the curing of the resin. In continuous production, the hot sticks are fed into a waxing unit for surface treatment. Because the sticks are hot, the wax dissolves and penetrates more deeply into the cellulose matrix, leaving some cellulose exposed on the surface, resulting in better grip. This phenomenon results in a greater amount of polar cellulose being present on the surface in the process according to the invention compared to non-processes according to the invention, thereby increasing the overall polarity of the paper stick surface. This increase is demonstrated by the fact that the contact angle of the paper stick according to the invention in water is lower than that of a paper stick prepared according to the prior art (Example 8). The paper stick can then be collected and stored for further use.

[0029] The production method of paper sticks is conventional in the case of heat treatment after waxing. Before being introduced into the production line for sweet products (lollipops), the waxed paper sticks can be exposed to a hot environment for a period of 15 minutes to 72 hours at a temperature of >40°C, preferably 70°C to 150°C. Particularly advantageous conditions are: temperature >45°C and time >36 hours. In this case, the sticks are exposed for a longer time because there is less air flow and less effective heat conduction. The end result is the same in any case: the wax is applied to the surface of the stick, penetrates into the interior of the cellulose matrix, and a part of the cellulose fibers is exposed on the surface, thereby determining the desired characteristics. After heating, the sticks are sent to the lollipop production line.

[0030] To characterize the heating effect, conventional rods and rods treated according to the present invention were examined using confocal Rayman microscopy. Confocal Rayman microscopy (CRM) allows the characterization and mapping of the distribution of different compounds within a sample. This technique can pinpoint different compounds (in this case, represented by lines) located on the surface of an object (mapping a specific area) or within it (within the object) to within tens of microns.

[0031] In the images obtained by surface mapping mode, the rods of the present invention showed that the cellulose fibers were evenly distributed on the surface, while the conventional rods had less cellulose exposed on the surface, and it was only on some small areas of the surface ( Figure 1 The rods of the present invention show how the wax and cellulose are at equal depths relative to the surface due to the heat treatment described above, which allows the wax to penetrate the cellulose matrix; whereas in conventional rods the wax is located on the surface, above the cellulose material ( Figure 2 ).

[0032] The sticks of the present invention exhibit acceptable or optimal breakaway forces after insertion into the lollipop. The breakaway forces were measured using a 500N load cell in traction mode on a vertical dynamometer within 6 minutes of exiting the cooling tunnel after the sticks were inserted, while the central volume of the edible material of the lollipop was still hot, i.e., above room temperature.

[0033] More particularly, the lollipop is characterized in that the detachment force of the stick of the invention from the edible part is ≥ 90 N (acceptable), preferably ≥ 150 N (optimal), when measured within 6 minutes of exiting the cooling tunnel after the stick is inserted into the edible part of the lollipop.

[0034] More particularly, the stick of the invention is characterized by a roughness of > 4.1 μm, measured as described above, or by a contact angle measured by the dynamic Wilhelmy method in the range 60° to 82°, and has a moisture content of not more than 6%, and has an acceptable detachment force after being inserted into a lollipop, i.e. a detachment force > 90 N.

[0035] When the sticks of the invention have a contact angle of 68 to 79° determined by the dynamic Wilhelmy method and a moisture content of 3.5 to 5.5%, they show the best detachment force after being inserted into a lollipop, ie a detachment force >150 N. Example

[0036] Example 1: Preparation of paper sticks according to prior art

[0037] Paper having the properties shown in Table 1 below was processed in a method according to the prior art, the paper rolls being cut to the rod length, an emulsion of water and PAE resin being applied, the paper being wound and the excess water being dried in a spiral dryer at a temperature of <50° C., and then a wax layer being applied according to the prior art, to give rods having the macroscopic parameters shown in Table 2.

[0038] Table 1 - Paper properties

[0039]

[0040] Table 2 - Rod properties

[0041]

[0042] Example 2: Preparation of paper sticks according to the present invention

[0043] Paper sticks were prepared as described in Example 1, except that the drying temperature was 98°C and the drying time was greater than 1 minute. The paper properties are shown in Table 1, and the macroscopic properties of the sticks are shown in Table 2.

[0044] Example 3: Instrumental Characterization of Rods Prepared in Example 1 (Prior Art) and Example 2 (Invention) - Surface Roughness

[0045] The residual moisture content of the bars produced in Examples 1 and 2 was measured at 105°C for 3 hours according to ASTM D644-99. Initial bending stiffness was measured according to ISO 5628 - UNI 10184. Roughness was measured using an FRT MicroProf® instrument over a length of 42 mm, obtaining 12,000 values. The roughness is reported in µm as the standard deviation of the maximum and minimum values ​​on a scale (0.06-2 mm).

[0046] Table 3 - Rod Properties

[0047]

[0048] The sticks made according to Example 2 of the present invention had less moisture, higher stiffness, and were rougher than the sticks made according to Example 1 of the prior art.

[0049] Example 4: Preparation of edible material for lollipops

[0050] According to the prior art, water, sugar, and glucose syrup are brought to a boil to obtain a concentrated solution of sugars and carbohydrates. A certain amount of a milk derivative mixture is added to this solution. The resulting solution is then cooked under vacuum to a moisture content of less than 4%, resulting in a molten mass. To this molten mass, known amounts of strawberry flavoring, strawberry juice concentrate, and citric acid are added, and the resulting molten mass is heated to a temperature greater than 100°C to obtain a final hard candy molten mass, which has not yet formed into a hard candy.

[0051] Example 5: Production of lollipops according to prior art

[0052] In a continuous process, the material from Example 4 was cooled and reduced to small pieces according to the prior art. Simultaneously with or immediately after the individual pieces of edible material were obtained, the lollipops from Example 1 were inserted using a high-speed machine. These lollipops were immediately fed into a cooling tunnel. The lollipops were then obtained according to the prior art, as shown in Table 4. Three technical experts evaluated the overall efficiency of the process, using a quality rating of insufficient, adequate, or excellent. In this specific case, the efficiency rating was "excellent."

[0053] Example 6: Production of lollipops according to the present invention

[0054] The procedure described in Example 5 was repeated, but using the sticks from Example 2. Thus, lollipops according to the invention were obtained, as shown in Table 4. Three technical experts evaluated the overall efficiency of the process, using a quality rating of insufficient, adequate, or excellent. In this particular case, the efficiency rating was "excellent."

[0055] Therefore, the use of the rods according to the invention does not reduce the efficiency of the method compared to the use of rods according to the prior art.

[0056] Table 4 - Macroscopic properties of lollipop

[0057]

[0058] Example 7: Measuring the Release Force of a Heated Rod

[0059] Ten (10) lollipops obtained according to Example 5 were taken out at the exit of the cooling tunnel and analyzed over a period of 6 minutes using a vertical dynamometer with a 500 N load cell. The sticks were attached to the upper clamps while the edible portion was inserted into the lower sleeve to secure them. The dynamometer was operated in a tensile mode and the force required to detach the edible portion or to break the stick was recorded. The detachment force values ​​are expressed as mean values ​​and Table 5 lists the minimum, mean, maximum and standard deviation of the 10 values.

[0060] This process was repeated multiple times in the same manner to obtain 10 lollipops obtained according to Example 6 to prepare multiple samples. The values ​​of the detachment force are expressed as average values. Table 5 lists the minimum value, average value, maximum value and standard deviation of the 10 values.

[0061] Table 5 - Breakaway force of rods according to the invention and according to the prior art

[0062]

[0063] The lollipops of Example 6 all have values ​​higher than the threshold value of 90N, while the lollipops of Example 5 have minimum, average and maximum values ​​lower than the threshold value.

[0064] Example 8: Instrumental Characterization of the Rods of Example 1 (Prior Art) and Example 2 (Invention) - Contact Angle

[0065] According to the following steps, use The contact angles of the rods obtained in Example 1 and Example 2 were measured using a tensiometer.

[0066] The instrument is loaded with Milli-Q® water.

[0067] It has been verified that the tension of water is 72mN / m.

[0068] The 15 bars to be measured were cut into lengths of 40-50 mm.

[0069] The rods are loaded into the instrument one at a time.

[0070] Immersion speed = 15mm / min.

[0071] Immersion depth = 20 mm.

[0072] Total readings per rod at each dip = 100 on 20 mm.

[0073] The rods are dipped for the first time.

[0074] The contact angle was obtained upon entry into the water during the first immersion and the average and standard deviation of all 1500 readings were obtained.

[0075] Then remove and soak for a second time.

[0076] The contact angle was obtained upon entry into the water during the second immersion and the average and standard deviation of all 1500 readings were obtained.

[0077] It is then removed, a water droplet is absorbed at the end, and the rod is removed from the apparatus.

[0078] The absorbed water was determined by the difference in weight of the bars before soaking and after the second soaking.

[0079] Table 6 - Contact Angle and Water Absorption

[0080]

[0081] Example 9 - Correlation between contact angle and breakaway force

[0082] Rods of Example 1 (prior art) and Example 2 (invention) were prepared in multiple successive batches, with slight variations in drying temperature. These batches were labeled 1-1, 1-2, 2-1, 2-2, 2-3, and 2-4, where the first digit represents the example number and the second digit represents the progressive batch number. The contact angles of these rods were measured as described in Example 8, and lollipops were produced using these rods as described in Examples 4, 5, and 6, while the efficiency of the process was evaluated. The breakaway force of each batch was measured as described in Example 7, and was rated as "acceptable" if the breakaway force was ≥ 90 N; "unacceptable" if the breakaway force was < 90 N; and "optimal" if the breakaway force was ≥ 150 N:

[0083] .

Claims

1. A paper and resin rod to which at least one lubricant is applied, said rod being characterized by a roughness of > 4.1 μm as determined by confocal microscopy with chromatic aberration.

2. The rod according to claim 1, wherein the roughness is in the range of 4.3 μm to 5 μm.

3. The rod according to claim 1 or 2, wherein the resin is epichlorohydrin polyamide.

4. The stick according to any one of claims 1 to 3, wherein the lubricating substance is wax.

5. The stick according to claim 4, wherein the wax is selected from polyolefin waxes.

6. Rod according to any one of the preceding claims, characterized in that The contact angles were in the range of 82° to 73°, as determined by the water immersion technique at the first immersion.

7. The rod according to claim 6, characterized in that The contact angle was <20° as determined by the water immersion technique during the second immersion.

8. The rod according to claim 7, characterized in that The water absorption is >10.7% by weight, as determined by the difference in weight after two immersions in water.

9. A method for preparing a rod comprising applying a lubricating substance to a preformed rod of paper and resin and subjecting it to a drying treatment, the method being characterized in that said treatment can be carried out before or after the application of the lubricating substance, in both cases resulting in cellulose fibers being evenly distributed on the surface of the rod.

10. Method for producing a rod according to claim 9, wherein the drying treatment is carried out at a temperature > 60°C for a period of 1 to 30 minutes, preferably at a temperature > 90°C, more preferably about 100°C, to a moisture content of not more than 6% by weight of the rod, and is carried out before applying a lubricating substance, preferably a wax.

11. Method for producing a rod according to claim 9, wherein the drying treatment is carried out at a temperature of >40°C, preferably 70°C to 150°C, for a period of 15 minutes to 72 hours, to a moisture content of not more than 6% by weight of the rod, and is carried out after applying a lubricating substance, preferably a wax.

12. Use of a stick according to claims 1 to 8 in a lollipop production factory.

13. Use according to claim 12, wherein the lollipop is characterized by a detachment force of the stick from the edible part of the lollipop of ≥ 90 N when tested within 6 minutes after the stick is inserted into the edible part and subsequently exiting the cooling tunnel.

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