A rose hip based peat flavored whiskey and process for its preparation

Abstract

The application discloses a rosehip-based peat-flavor whisky and a preparation process thereof, and belongs to the technical field of flavor regulation of distilled liquor. Fresh rosehips are washed, thorn-removed, sliced and dried to a moisture content of 15-20% in a wet base, and then subjected to heat treatment under verified short-time high-temperature conditions. After cooling, the rosehips are extracted with non-peat-type whisky base liquor with an alcohol content of 30-60%vol at a ratio of 1g:15-25mL at 18-25 DEG C for 15-30d, and then subjected to solid-liquid separation to obtain rosehip-flavored peat-flavor whisky liquor, which can be further aged in oak barrels and blended. The process combines the moisture content of rosehips, heat treatment conditions and alcohol extraction conditions, and takes into account the formation of peat-like smoke flavor, the retention of rosehip fruit flavor and the control of excessive heat treatment.

Description

Technical Field

[0001] This invention relates to the field of distilled spirit processing and flavor control technology, specifically to a peat-flavored whisky based on prickly pear and its preparation process, and more specifically to a preparation process that selectively changes the volatile flavor composition of prickly pear by controlling the material state, degree of heat treatment and subsequent alcohol extraction conditions when the prickly pear enters the high-temperature treatment stage, and introduces the resulting complex flavor into a non-peaty whisky base spirit. Background Technology

[0002] Peated flavor is a highly recognizable style characteristic of some whisky products. Traditional peated whisky is usually smoked during the malting process using the smoke produced by burning peat. This allows volatile phenols and other aroma compounds in the smoke to be absorbed by the malt and then enter the whisky during subsequent saccharification, fermentation, distillation, and aging, thus forming a complex flavor profile including smoky, woody, and medicinal notes.

[0003] Traditional peat smoking processes are highly dependent on the source of peat, its combustion state, and the degree of smoking. Different raw materials and smoking conditions can all lead to changes in the final volatile phenolic composition. Existing technologies can also introduce volatile phenols, aromatic aldehydes, and furans formed during the heat treatment of oak and other woody materials into the whisky, thereby obtaining smoky, woody, vanilla, and toasty aromas.

[0004] The heat behavior of fruit-based plant materials differs significantly from that of low-moisture wood materials such as oak. Fruits contain a high amount of water, as well as sugars, organic acids, polyphenols, and various volatile or semi-volatile flavor components. While directly increasing the processing temperature can promote the formation of some roasting or smoking flavors, it can also easily lead to the loss of the original fruit aroma and enhance non-target flavors such as burnt and pungent notes.

[0005] Prickly pear has a distinct fruity and acidic aroma, and its current uses are mainly concentrated in fermentation, maceration, juice production, or blending. When prickly pear is heated, different flavor components undergo varying degrees of transformation, volatilization, or redistribution. However, simply drying or raising the roasting temperature cannot automatically produce the complex smoky flavor suitable for whisky systems.

[0006] Therefore, when using plant-based raw materials for non-peat smoking and aroma enhancement, it is still necessary to take into account the formation of smoky flavor, the preservation of the raw material's own unique aroma, and the control of excessive thermal reactions, so that the aroma enhancement process has good controllability and reduces problems such as indistinct smoky characteristics caused by insufficient treatment and loss of fruit aroma, scorching, and irritation caused by excessive treatment. Summary of the Invention

[0007] In view of this, the present invention proposes a peat-flavored whisky based on prickly pear and its preparation process. By combining the control of the state of prickly pear material, short-time high-temperature heat treatment and alcohol extraction, the problem of the difficulty in simultaneously achieving the formation of smoky flavor, the preservation of the characteristic fruity aroma of raw materials and the control of excessive heat reaction during the process of plant-derived smoking and aroma enhancement is solved.

[0008] The technical solution of the present invention is implemented as follows: The present invention provides a preparation process for peat-flavored whisky based on prickly pear, including prickly pear pretreatment, heat treatment, flavor extraction and solid-liquid separation steps; prickly pear-flavored peaty whisky liquid is obtained through solid-liquid separation, and the obtained liquid can be further aged in oak barrels and blended.

[0009] In some embodiments, the prickly pear is a mature, fresh prickly pear fruit free from rot and mold, which is washed, de-thorned, and then cut into slices. The thickness of the slices is 3–8 mm, preferably 4–6 mm. Controlling the size of the slices helps to reduce differences in heat and mass transfer during subsequent drying and heat treatment processes within the same batch of prickly pears.

[0010] In some embodiments, the prickly pear is dried at 30–50°C, so that the wet basis moisture content of the prickly pear entering the high-temperature treatment step is 10%–30%. Experiments show that a wet basis moisture content of 15%–20% can better balance the subsequent formation of smoky flavor and the control of over-charring; therefore, 15%–20% is preferred, and more preferably 16%–19%. Wet basis moisture content refers to the percentage of the mass of water in the sample to the total mass of the wet sample.

[0011] In some embodiments, the prickly pears that have reached the target moisture content are subjected to high-temperature heat treatment. To investigate the effects of temperature and time on the heat treatment behavior of the prickly pears, this invention sets up single-factor experiments for temperature and time: the temperature single-factor experiment examines the effects at 180–230°C with a fixed treatment time of 10 min; the time single-factor experiment examines the effects at 5–30 min with a fixed temperature of 220°C. The above-mentioned ranges are used to determine suitable treatment conditions and do not imply that any combination between 180–230°C and 5–30 min will have the same technical effect.

[0012] In some embodiments, based on the results of the single-factor experiments described above, suitable heat treatment conditions are selected from 200°C for 10 min, 210°C for 10 min, and 220°C for 5–15 min; more preferably, 210°C for 10 min or 220°C for 5–15 min, and even more preferably, 220°C for 10 min. The heat treatment equipment is preheated to the set temperature before adding the prickly pear. The prickly pear is laid out in a single layer or with minimal stacking. Timing begins after the equipment temperature returns to the set value, and the equipment is cooled promptly after treatment.

[0013] In some embodiments, heat-treated prickly pear is extracted using a non-peated whiskey base spirit. The alcohol content of the non-peated whiskey base spirit can be adjusted within the range of 30% to 60% vol; the ratio of heat-treated prickly pear to the base spirit is 1 g: 15 to 25 mL; the extraction temperature is 18 to 25°C; and the extraction time is 15 to 30 days. The above-mentioned ratio and extraction time are adjustable process conditions for the flavor migration stage and can be selected according to the flavor intensity of the target spirit. Furthermore, a base spirit of 36% to 40% vol, a ratio of 1 g: 20 mL, and an extraction time of 15 to 18 days have good process adaptability; even further, a 36% vol base spirit can be used at a ratio of 1 g: 20 mL at 20 ± 2°C for 15 days.

[0014] In some embodiments, the non-peated whisky base spirit referred to in this invention refers to a whisky base spirit whose malt or grain raw material processing stage was not peat-smoked. All base spirits with different alcohol contents used in the experiment were adjusted to the set alcohol content using purified water from the same batch of non-peated whisky base spirits to reduce the interference of differences in the initial spirit volume on the evaluation of smoky flavor. Alcohol content gradient experiments showed that increasing the alcohol content generally facilitates the entry of some volatile phenols and aromatic aldehydes into the spirit, but the overall harmony does not increase synchronously with the alcohol content. 36%–40% vol can better balance the extraction of smoky aroma components, the expression of prickly pear fruit aroma, and the control of irritation.

[0015] In some embodiments, solid-liquid separation is performed after extraction to obtain a prickly pear-infused peaty whisky liquid. This liquid already possesses smoky and complex fruity aromas contributed by heat-treated prickly pear before aging in oak barrels; therefore, oak barrel aging is not a necessary condition for the formation of the core aroma system of this invention.

[0016] In some implementations, the prickly pear-infused peaty whisky is placed in oak barrels and aged for 12 months at 15–22°C in the dark. Aging primarily promotes the integration of the prickly pear's smoky and fruity aromas with the whisky's own grain, woody, and vanilla notes. After aging, the whisky is filtered. When the measured alcohol content at 20°C is higher than 43% vol, purified water is added; when the measured alcohol content is lower than 40% vol, a non-peaty whisky base spirit with an alcohol content higher than 43% vol is added. Alternatively, both methods can be used simultaneously, depending on the measured alcohol content, to achieve a final alcohol content of 40%–43% vol at 20°C.

[0017] The applicant's research revealed that different volatile phenols exhibited varying trends during heat treatment. While guaiacol generally increased with increasing heat treatment intensity, 4-vinylguaiacol did not increase proportionally and even decreased within a certain treatment range. Therefore, this invention does not simply increase all smoky aroma components, but rather regulates the volatile flavor composition by coordinating the moisture content of the prickly pear with the degree of heat treatment.

[0018] The present invention has the following advantages over the prior art: By controlling the moisture content of the prickly pear during the high-temperature treatment stage in conjunction with the heat treatment temperature, time, and subsequent alcohol extraction conditions, the present invention retains the aroma of the prickly pear while forming a distinct peat-like smoky characteristic, and provides a process window for controlling the scorching and irritating flavor caused by over-treatment; compared with the apple and pear raw materials in the comparative test of this application, the prickly pear can obtain a more obvious smoky aroma contribution under the same heat treatment and extraction conditions, and can maintain a more obvious fruity aroma characteristic compared with the oak aroma system used in this application, thus forming a complex flavor that harmonizes the smoky aroma and the aroma of the prickly pear. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments and experimental examples. The following embodiments are used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Unless otherwise stated, all embodiments and experimental examples use the same batch of ripe, unrotten and mold-free fresh prickly pear fruit and the same batch of non-peaty whisky base spirit; except for the factors under investigation, the operating conditions of each comparative group are kept consistent.

[0020] I. Raw materials, equipment and general operating conditions Fresh prickly pear fruit was washed with running water to remove thorns and inedible parts, then cut longitudinally into slices 5±1 mm thick. The prickly pear slices were laid in a single layer in a hot air drying device, with a layer thickness controlled at 10–20 mm, and dried at 35–40°C. During the drying process, samples were periodically taken to measure the wet-basis moisture content; drying was stopped once the target range was reached. Unless otherwise specified, the wet-basis moisture content of the prickly pear was controlled at 17.0%±0.5% in each embodiment.

[0021] The wet basis moisture content of prickly pear refers to the percentage of water mass in the sample relative to the total wet sample mass. It is determined according to the distillation method of GB 5009.3-2016, with each sample measured in triplicate and the average value taken.

[0022] High-temperature heat treatment is carried out in an electric thermostatic drying oven under an air atmosphere. Before treatment, the equipment is preheated to the target temperature. The prickly pear material is evenly spread in a single layer on a tray and then placed into the equipment. Timing begins after the equipment temperature returns to the set value. After treatment, the material is immediately removed and cooled to 18-25°C in a clean, light-proof environment before extraction.

[0023] The non-peated whisky base spirits used in the experiment were from the same production batch, and their malt processing was not peat-smoked. All alcohol content groups were adjusted to the set alcohol content using purified water from the same batch of base spirits. Unless otherwise stated, 36% vol non-peated whisky base spirits were used, with a ratio of 1g prickly pear to 20mL base spirits, and macerated for 15 days at 20±2℃, in the dark, and in a sealed environment, gently shaken once every 24 hours.

[0024] When aging was required, all groups used new 5L American white oak barrels with moderately toasted inner walls, aged for 12 months at 15–22°C in the dark. By using oak barrels of the same material, capacity, toasting degree, and number of uses, the impact of barrel differences on inter-group comparisons was reduced.

[0025] II. Detection of Volatile Flavor Components Guaiacin, 4-methylguaiacin, 4-ethylguaiacin, 4-vinylguaiacin, eugenol, and vanillin in the wine were determined by headspace solid-phase microextraction-gas chromatography-mass spectrometry. 5.0 mL of wine sample was added to a 20 mL headspace vial, along with 1.5 g of sodium chloride, and the vial was sealed. A 50 / 30 μm DVB / CAR / PDMS solid-phase microextraction fiber was used. After equilibration at 70 °C for 10 min, headspace extraction was performed for 50 min. Following extraction, desorption was carried out at 250 °C for 5 min.

[0026] Gas chromatography was performed using a DB-FFAP capillary column (60 m × 0.25 mm × 0.25 μm). The initial temperature was 50 °C, held for 2 min, then increased to 240 °C at a rate of 5 °C / min and held for 1 min. The injection port temperature was 250 °C. The carrier gas was helium with a purity of not less than 99.99%. Mass spectrometry was performed using an electron impact ion source with an electron energy of 70 eV and an ion source temperature of 230 °C. The scan range was 40–550 amu. For each target compound, corresponding standards were used to prepare a standard series in an ethanol-water system with the same alcohol content as the analyte, and an external standard curve was established. The correlation coefficient R0 was [not specified]. 2 All values ​​were not less than 0.995. Each sample was measured in triplicate, and the average value of the three measurements is shown in the table.

[0027] III. Detection of furfural and 5-HMF Furfural and 5-hydroxymethylfurfural were determined by high-performance liquid chromatography (HPLC). A C18 reversed-phase column (4.6 mm × 250 mm, 5 μm) was used. The mobile phase was methanol-water (v / v) 10:90, the flow rate was 1.0 mL / min, the column temperature was 30 °C, the detection wavelength was 285 nm, and the injection volume was 10 μL. The wine sample was filtered through a 0.22 μm filter suitable for water-ethanol systems before injection. An external standard curve was established using the corresponding standards. R0 2 All are not less than 0.995.

[0028] IV. Sensory Evaluation A panel of five evaluators with experience in sensory evaluation of alcoholic beverages and who had received standardized training was formed. 20 mL of each sample was placed in the same tasting glass, equilibrated at 20±2℃, and then blind-tasted using a random three-digit code in a random order. Different samples were rinsed with room-temperature drinking water before being tested. Evaluation indicators included peaty smoky aroma, prickly pear fruit aroma, burnt flavor, irritation, and overall harmony, each scored on a scale of 0 to 10. Each evaluator scored independently, and the results in the table are the average scores from the five evaluators.

[0029] Example 1 The prickly pear was dried to a wet basis moisture content of 17.2%, treated at 220°C for 10 minutes, and then cooled to approximately 20°C. A 36% vol non-peaty whisky base was extracted at a ratio of 1g:20mL at 20±2°C for 15 days. The resulting whisky was filtered to obtain a prickly pear-infused peaty-flavored spirit. This spirit was aged in the aforementioned oak barrels for 12 months. After aging, it was filtered and blended to a 20°C alcohol content of 40%–43% vol according to the aforementioned blending method. The resulting spirit has a distinct and mellow peaty smoky aroma, with a still discernible prickly pear fruitiness, accompanied by vanilla and woody notes.

[0030] Example 2 The treatment was essentially the same as in Example 1, except that the wet base moisture content of the prickly pear was 17.4%, and the high-temperature heat treatment conditions were 200°C for 10 minutes. The resulting wine had a weaker smoky aroma than in Example 1, but significantly stronger than the untreated group, and the prickly pear fruit aroma was well preserved.

[0031] Example 3 The process was essentially the same as in Example 1, except that the wet base moisture content of the prickly pear was 17.0%, it was treated at 210°C for 10 minutes, and extracted with a 40% vol non-peaty whisky base at a ratio of 1 g: 20 mL for 18 days. The resulting spirit had a distinct smoky aroma while retaining the fruity fragrance of the prickly pear.

[0032] Example 4 The prickly pear was dried to a wet basis moisture content of 15.3% and treated at 220°C for 15 minutes. It was then extracted with a 36% vol non-peaty whisky base at a ratio of 1 g:20 mL for 15 days. The resulting spirit exhibited more pronounced smoky and toasty characteristics, and while the prickly pear fruit aroma was still discernible, the degree of caramelization was higher than in Example 1.

[0033] Example 5 The prickly pear was dried to a wet basis moisture content of 19.8% and treated at 220℃ for 10 minutes. A 40% vol non-peaty whisky base was used for extraction at a ratio of 1g:20mL for 15 days. The resulting spirit exhibited a pronounced smoky aroma, well-preserved fruit flavors, and an overall smooth character.

[0034] Comparative Example 1: Low Temperature Treatment The prickly pear was dried to a wet basis moisture content of approximately 17%, treated at 85°C for 30 minutes, and then extracted with a 36% vol non-peaty whisky base spirit at a ratio of 1 g: 20 mL for 15 days, and aged under the same conditions as in Example 1. The resulting spirit is dominated by prickly pear and ripe fruit aromas, with a relatively weak peaty smoky aroma.

[0035] Comparative Example 2: Without high-temperature treatment After drying the prickly pear to approximately 17% wet-basis moisture content, it was not subjected to high-temperature heat treatment. Instead, it was directly extracted with a 36% vol non-peaty whisky base at a ratio of 1g:20mL for 15 days, with the remaining treatments being the same as in Example 1. The resulting spirit had a pronounced fruity aroma, but the typical peaty smoky flavor was not prominent.

[0036] The main volatile flavor components of Examples 1, 2 and Comparative Examples 1-2 after aging in the same oak barrels are shown in Table 1.

[0037] Table 1. Main volatile flavor components of the examples and comparative examples.

[0038] As shown in Table 1, high-temperature treatment did not simultaneously increase the content of all volatile phenols. In particular, as the degree of treatment increased, guaiacol increased overall, while 4-vinylguaiacol decreased overall, indicating that the high-temperature treatment of prickly pear resulted in a redistribution of volatile flavor components, rather than simply increasing the content of all smoky phenols.

[0039] Experimental Example 1: The Effect of Heat Treatment Temperature The same batch of prickly pears was dried to a wet basis moisture content of 17.0% ± 0.5%, and treated at 180℃, 190℃, 200℃, 210℃, 220℃, and 230℃ for 10 min each. All groups were extracted with 36% vol non-peaty whisky at a ratio of 1 g: 20 mL for 15 days. This experiment was used to evaluate the effect of temperature changes when the treatment time was fixed at 10 min, and was not intended to prove that different temperatures could be arbitrarily combined with other treatment times. To eliminate the influence of oak barrels on the test results, all tests were conducted after extraction and before the oak barrels were placed in the barrels. The results are shown in Tables 2 and 3.

[0040] Table 2. Main volatile flavor components at different heat treatment temperatures.

[0041] The units for all chemical components in Table 2 are μg / L.

[0042] Table 3 Sensory evaluation results at different heat treatment temperatures

[0043] The results showed that guaiacol generally increased with increasing heat treatment temperature, while 4-vinylguaiacol generally decreased. When the temperature was further increased to 230℃, although the peat-like smoky aroma remained strong, furfural and 5-HMF increased significantly, while the prickly pear fruit aroma decreased and the scorching and pungent sensation increased. Under a fixed treatment time of 10 min, 200℃, 210℃, and 220℃ all effectively balanced the formation of smoky flavor with the preservation of fruit aroma, with 210–220℃ showing the best overall effect.

[0044] Experimental Example 2: The Influence of Water Content on Prickly Pear The prickly pears were dried to approximately 10%, 15%, 17%, 20%, 25%, and 30% moisture content on a wet basis, respectively, and then treated at 220°C for 10 min. They were subsequently extracted with 36% vol non-peaty whisky at a ratio of 1 g: 20 mL for 15 days, and the results were measured before casking. The results are shown in Tables 4 and 5.

[0045] Table 4. Main volatile flavor components of prickly pear at different moisture contents.

[0046] The units for all chemical components in Table 4 are μg / L.

[0047] Table 5 Sensory evaluation results under different moisture contents of prickly pear

[0048] The results showed that at higher moisture content, the degree of smoky aroma formation decreased under the same temperature and time; at lower moisture content, although guaiacol was higher, 5-HMF and char flavor increased, while fruit aroma decreased. Under the conditions of this experiment, a wet basis moisture content of 15%–20% could better balance smoky aroma formation, fruit aroma retention, and over-charring control.

[0049] Experimental Example 3: Effect of Heat Treatment Time Prickly pear with a wet basis moisture content of approximately 17% was treated at 220°C for 5, 10, 15, 20, and 30 minutes, respectively, with the remaining extraction conditions consistent with Example 1. This experiment was used to evaluate the effect of treatment time when the heat treatment temperature was fixed at 220°C, and is not intended to prove that 5–15 minutes can be directly applied to other heat treatment temperatures. The results are shown in Tables 6 and 7.

[0050] Table 6. Main volatile flavor components under different heat treatment times.

[0051] The units for all chemical components in Table 6 are μg / L.

[0052] Table 7 Sensory evaluation results under different heat treatment times

[0053] When the processing time is extended to 10–15 min, the smoky aroma becomes more pronounced. However, with further extension, the increase in the target flavor slows down, while the fruity aroma decreases and the indicators of charring and excessive heat reaction continue to increase. Therefore, at 220℃, 5–15 min can produce good peat-like smoky characteristics, with 10–15 min showing the best overall effect and 10 min showing the best overall coordination.

[0054] Experimental Example 4: The Effect of Alcohol Content on Non-Peated Whisky Base Spirits Prickly pears treated at 220℃ for 10 min were extracted with non-peaty whisky base spirits of the same batch at 30%, 36%, 40%, 50%, and 60% vol, respectively, at a solid-liquid ratio of 1 g:20 mL, for 15 days. The alcohol content groups were adjusted to the set values ​​using purified water from the same batch of base spirits. The results are shown in Tables 8 and 9.

[0055] Table 8. Main volatile flavor components at different base alcohol contents.

[0056] Table 9 Sensory evaluation results for different base spirits with different alcohol contents

[0057] The results showed that, overall, higher alcohol content facilitated the incorporation of some nicotinic phenols and aromatic aldehydes into the wine, but the overall harmony did not improve in tandem with alcohol content. A concentration of 36%–40% vol provided a better balance between smoky aromas, fruity notes, and pungent notes.

[0058] Experimental Example 5: Comparison of Different Fragrance Raw Materials Prickly pear, apple, pear, and oak were selected as flavoring ingredients. Each ingredient was controlled to have similar moisture content and size, treated at 220°C for 10 minutes, and then extracted with a 36% vol non-peaty whisky base at a ratio of 1 g: 20 mL for 15 days. All samples were tested before entering the oak barrels. The results are shown in Tables 10 and 11.

[0059] Table 10 Main volatile flavor components of different flavoring raw materials

[0060] The units for all chemical components in Table 10 are μg / L.

[0061] Table 11 Sensory evaluation results of different fragrance ingredients

[0062] The results showed that the oak raw material used in this experiment could form strong smoky and woody characteristics, but weak fruity aroma; apple and pear could retain strong fruity aroma, but insufficient smoky aroma. While not all smoky flavor indicators were highest in prickly pear, it could simultaneously maintain a relatively obvious peat-like smoky aroma and fruity aroma characteristics, with overall better harmony than other comparative raw materials in this experiment. Therefore, the effect obtained by this invention is not simply due to the high-temperature treatment of any plant material, but is related to the flavor system of the prickly pear raw material itself and its heat treatment behavior in the stated material state.

[0063] Experimental Example 6: Flavor Contribution at Different Processing Stages S0 was a non-peaty whisky base spirit without prickly pear treatment; S1 was the spirit after 15 days of prickly pear maceration without high-temperature treatment; S2 was the spirit after 15 days of prickly pear maceration with treatment at 220℃ for 10 minutes and before being placed in oak barrels; and S3 was the spirit of S2 after 12 months of aging in oak barrels. The results are shown in Table 12.

[0064] Table 12 Main volatile flavor components at different processing stages

[0065] Table 12 lists all components in μg / L. The results indicate that heat treatment of the prickly pear extract before aging in oak barrels significantly altered various volatile phenols and vanillin associated with smoky aromas in the wine. Therefore, the core aroma-enhancing effect of this invention is not solely formed by subsequent oak barrel aging; oak barrel aging is primarily used to further integrate and mature the wine's flavor profile.

[0066] Experimental Example 7: Comparison of volatile flavor composition with typical peaty single malt whisky To further evaluate the composition of volatile components related to smoky flavor in the prickly pear-infused spirit obtained in this invention, and to provide a reference for a typical peaty flavor spirit, two reference tests were conducted on commercially available Laphroaig 10-year-old single malt whisky, designated as Typical Peated Flavor Reference Sample 1 and Typical Peated Flavor Reference Sample 2, respectively. Simultaneously, a prickly pear group without high-temperature treatment and a prickly pear group treated at 220℃ for 10 min were selected for comparison. All samples were measured using the aforementioned method for detecting volatile flavor components, and the results are shown in Table 13.

[0067] Table 13 Comparison of volatile flavor components between the sample of this invention and a typical peat flavor reference sample

[0068] Table 13 lists all components in μg / L. As shown in Table 13, the contents of guaiacol, 4-methylguaiacol, and 4-ethylguaiacol in the typical peat-flavored reference sample are significantly higher than those in the prickly pear-flavored spirit of this invention, indicating that the spirit obtained in this invention is not a simple replication of the high-volatile phenol composition of traditional peat-smoked whisky. Compared to the untreated prickly pear group, the contents of guaiacol, 4-methylguaiacol, 4-ethylguaiacol, eugenol, and vanillin in the spirit after treatment at 220℃ for 10 min are significantly increased, while 4-vinylguaiacol decreases, further demonstrating that heat treatment causes selective changes in the composition of different flavor components. Meanwhile, guaiacol, 4-methylguaiacol, 4-ethylguaiacol, eugenol, and 4-vinylguaiacol, all volatile phenols related to smoky flavor, were detected in both the 220℃-treated group and the typical peat-flavored reference sample, with 4-vinylguaiacol being in the same order of magnitude. Based on the aforementioned sensory evaluation, it can be seen that the spirit obtained by this invention has formed a flavor base composed of a variety of volatile phenols related to smoky flavor, but its absolute composition of volatile phenols is still significantly different from that of typical strongly peated single malt whisky.

[0069] Comprehensive analysis The above results indicate that the pretreatment, heat treatment, and alcohol extraction of prickly pear are not simply a combination of independent routine steps. The moisture content of the prickly pear during the heat treatment stage affects its heating process; the heat treatment temperature and time jointly affect the compositional relationship between different volatile phenols and thermal reaction products; and the alcohol content of the non-peaty whisky base spirit affects the extent to which the flavor substances formed during heat treatment enter the spirit.

[0070] When the treatment level is insufficient, the formation of peat-like smoky flavor is limited; when the treatment level is excessive, although some smoky phenols can still increase, the prickly pear fruit aroma is lost, and negative properties such as furfural, 5-HMF, scorching, and irritation are enhanced. Single-factor experiments show that when the heat treatment time is fixed at 10 min, 200℃, 210℃, and 220℃ are all feasible, with 210–220℃ showing the best overall effect; when the heat treatment temperature is fixed at 220℃, 5–15 min can form good peat-like smoky characteristics. Therefore, the preferred heat treatment conditions of this invention are 200℃ for 10 min, 210℃ for 10 min, and 220℃ for 5–15 min, with 220℃ for 10 min showing the best overall effect. During the alcohol extraction stage, a base spirit of 30%–60% vol non-peaty whisky, a material-to-liquid ratio of 1g:15–25mL, and an extraction time of 15–30 days can be used as the range for process adjustment. Among them, a base spirit of 36%–40% vol with a material-to-liquid ratio of 1g:20mL and an extraction time of 15–18 days can be considered as the preferred combination, and an extraction time of 1g:20mL for 15 days with a base spirit of 36% vol is a further preferred condition.

[0071] A comparison with typical peaty single malt whiskies further demonstrates that the spirit obtained in this invention does not aim to replicate the high volatile phenolic composition of traditional peaty whiskies. Instead, it forms a compositional system containing various volatile phenols associated with typical smoky flavors after heat treatment of the prickly pear, while retaining the fruity aromas characteristic of the prickly pear itself. Therefore, the spirit produced by this invention is a complex flavor system with distinct peaty-like smoky characteristics and prickly pear fruit aromas, and its flavor composition is identifiablely different from that of traditional strongly peaty single malt whiskies.

[0072] The above results also demonstrate that the technical contribution of this invention does not lie in the use of heat treatment alone, a known operation, but in the coordinated control of the water content before entering the high-temperature step, the heat treatment conditions verified in practice, and the subsequent alcohol extraction conditions, based on the material state and thermal reaction characteristics of prickly pear. This results in a complex flavor that is different from the apple, pear baking aroma and oak aroma systems tested in this application.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, equivalent substitutions or conventional adjustments to specific operating conditions based on the disclosure of the present invention, without departing from the technical concept of the present invention, shall fall within the protection scope of the corresponding claims of the present invention.

Claims

1. A process for preparing peat-flavored whisky based on prickly pear, characterized in that, Includes the following steps: (1) Wash the fresh prickly pear fruit, remove the thorns and slice it, and dry it until the wet basis moisture content is 15% to 20%; (2) The prickly pear obtained in step (1) is subjected to heat treatment. The heat treatment conditions are selected from one of 200℃ for 10 min, 210℃ for 10 min and 220℃ for 5 to 15 min, to obtain heat-treated prickly pear. (3) After cooling the heat-treated prickly pear to 18-25°C, mix it with a non-peaty whisky base spirit with an alcohol content of 30%-60%vol at a ratio of 1g:15-25mL and extract it at 18-25°C for 15-30 days. (4) After the extraction is completed, solid-liquid separation is carried out to obtain prickly pear-flavored whisky liquid.

2. The preparation process according to claim 1, characterized in that, In step (1), the prickly pear is cut into slices with a thickness of 3-8 mm and dried at 30-50°C to the wet basis moisture content.

3. The preparation process according to claim 2, characterized in that, The thickness of the sheet material is 4-6 mm, and the drying temperature is 35-40℃.

4. The preparation process according to claim 1, characterized in that, The heat treatment conditions in step (2) are 210℃ for 10 min or 220℃ for 5 to 15 min.

5. The preparation process according to claim 4, characterized in that, The heat treatment conditions in step (2) are 220℃ for 10 min.

6. The preparation process according to claim 1, characterized in that, The alcohol content of the non-peaty whisky base spirit in step (3) is 36% to 40% vol, the ratio of heat-treated prickly pear to non-peaty whisky base spirit is 1g:20mL, and the extraction time is 15 to 18 days.

7. The preparation process according to claim 6, characterized in that, The non-peaty whisky base spirit has an alcohol content of 36% vol, an extraction temperature of 20±2℃, and an extraction time of 15 days.

8. The preparation process according to claim 1, characterized in that, After the heat treatment in step (2) is completed, the heat-treated prickly pear is cooled to 18-25°C in air atmosphere before the extraction in step (3).

9. The preparation process according to claim 1, characterized in that, It also includes placing the prickly peat-flavored whisky obtained in step (4) in oak barrels and aging it for 12 months at 15-22°C in the dark, and then filtering it after aging.

10. The preparation process according to claim 9, characterized in that, After aging, the spirit is blended with purified water and / or a non-peaty whisky base spirit with an alcohol content higher than 43% vol, so that the resulting spirit has an alcohol content of 40% to 43% vol at 20°C.

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