Carya cathayensis with low furfural content and processing method thereof

Abstract

The invention provides a processing method of pecan with low furfural substances, which belongs to the field of food processing and mainly comprises the following steps: preparing materials, removing astringency, boiling sugar, frying, drying and baking. The processing method of the pecan with low furfural substances is simple and convenient in steps and relatively low in processing cost, and the rosemary extract is selected to reduce the content of the furfural substances in the pecan, so that the influence of high-content hot processing harmful substances is effectively regulated and controlled. The made rosemary extract hickory nut combines the flavors of hickory nut and rosemary, is crispy and delicious, and is rich in nutrition, and meanwhile, low-furfural substances meet the requirements of food health.

Description

Technical Field

[0001] The invention relates to low-furfural pecans and also relates to a processing method of low-furfural pecans. Background Art

[0002] Pecans are a type of nut with high production and sales in my country. As a healthy economic crop, their kernels are rich in protein and unsaturated fatty acids, as well as a variety of nutrients beneficial to human health, such as essential amino acids, minerals, polyphenols, and flavonoids. These nutrients in nuts readily undergo Maillard reactions at high temperatures, forming flavor compounds that contribute to their excellent taste and volatile properties.

[0003] However, high temperatures can also cause chemical reactions in certain food components, such as the Maillard reaction and caramelization. The Maillard reaction is a complex reaction between carbonyl compounds (reducing sugars) and amino compounds (amino acids and proteins), ultimately producing brown or even black macromolecular substances called melanoidins or pseudomelanins, hence the name carbonyl-amino reaction. Caramelization occurs when sugars, especially monosaccharides, are heated to temperatures above their melting point (generally above 140°C to 170°C) in the absence of amino compounds, leading to dehydration and degradation. Sugars react with intense heat to form two types of substances: one dehydrates to form caramel, while the other decomposes at high temperatures to form small molecule aldehydes and ketones. Further condensation and polymerization of these small molecule aldehydes and ketones also produce darker substances. Therefore, while heat processing can generate flavor and improve food quality, it can also produce harmful substances such as acrylamide and furfural, potentially creating harmful effects.

[0004] Furfurals are small molecules with furan rings, commonly found in thermally processed foods and foods high in sugar, such as bread, juice, coffee, and milk. Furfurals can be used as indicators of thermal processing, such as baking. The European Food Safety Authority (EFSA) has established an acceptable daily intake (ADI) of 0.5 mg / kg bw for furfural. Studies have shown that these substances can be toxic at higher concentrations. For example, oral administration of furfural is potentially carcinogenic, increasing the incidence of hepatocellular adenomas and liver cancer in mice. Orally ingested 5-hydroxymethylfurfural is also readily converted into 5-sulfomethylfurfural (SMF) in the body, making 5-HMF potentially genotoxic and mutagenic. Therefore, it is necessary to control the content of furfurals in food.

[0005] Many exogenous additives can inhibit the accumulation of furfurals by affecting reaction precursors or intermediates, such as glyoxal, methylglyoxal, and deoxyketose. Polyphenols, for example, generally possess significant antioxidant capacity, and several studies have shown that they have a certain influence on the formation of furfurals. For example, green rooibos tea and β-cyclodextrin extracts exhibit significant anti-browning activity in canned apples. Catechins can react with precursors and intermediates to form adducts, inhibiting the formation of furfural in sugarcane juice.

[0006] Rosemary, a plant of the genus Rosmarinus in the Lamiaceae family, contains phenolic compounds. Rosemary extracts derived from rosemary are widely used as food additives. Rosmarinic acid, a natural antioxidant found in rosemary extracts, is already used in the food industry and is a valuable natural resource with both edible and medicinal properties. Studies have shown that rosmarinic acid, a major component of rosemary extract, can significantly inhibit the formation of HMF. Summary of the Invention

[0007] In response to the harmful effects of high levels of furfural in the heat-processed pecans, the present invention aims to provide pecans low in furfural and a processing method thereof. By adding edible rosemary extract, the furfural formed during the processing of pecans is regulated, thereby obtaining a new type of pecan delicacy that is healthy, nutritious, and has the flavor of rosemary and pecans.

[0008] The present invention provides a low-furfural pecan. By adding edible rosemary extract, the furfural formed during the processing of pecan is regulated, thereby obtaining a healthy, nutritious, and novel pecan delicacy with the flavor of rosemary and pecan.

[0009] Specifically, a low-furfural pecan processing method includes the following steps:

[0010] Remove astringency: Boil the pecan kernels in water for 25 to 30 minutes, remove them and rinse with cold water for later use;

[0011] Boil sugar: weigh white sugar, salt, and rosemary extract, add 45-50 ml of water to dissolve and mix evenly, heat and boil until the volume of the syrup is concentrated to one-fourth of its original size;

[0012] Stir-frying: add the de-astringent pecan kernels into the syrup, stir-fry continuously for 15 minutes, so that the syrup containing rosemary extract evenly coats the pecan kernels to obtain a semi-finished product.

[0013] In the preferred embodiment, the raw material ratio (by weight) is: 45-50 g white sugar / kg pecan, 8-10 g salt / kg pecan, and 0.20-0.24 g rosemary extract / kg pecan.

[0014] The present invention also provides a method for processing pecans with low furfural content, comprising the following steps:

[0015] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0016] (2) removing astringency: boiling the pecan kernels obtained in step (1) in water at 80-110° C. for 25-30 minutes, stirring continuously during the process to completely remove astringency, removing the kernels and rinsing with cold water for later use;

[0017] (3) Boiling sugar: weigh a certain amount of white sugar, salt, and rosemary extract, add 45-50 ml of water to dissolve and mix evenly, and boil over low heat for 15-20 minutes;

[0018] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry over medium heat for about 5 to 10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, to obtain a semi-finished product.

[0019] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 50-60°C for 2-3 hours;

[0020] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130-135° C. for 50-60 minutes and then cooling to obtain processed pecans containing low furfural substances.

[0021] Preferably, the proportions (by weight) of the raw materials used are as follows: 45-50 g white sugar / kg pecan, 8-10 g salt / kg pecan, and 0.20-0.24 g rosemary extract / kg pecan.

[0022] Preferably, the low-fire temperature in step (3) is 80-130°C.

[0023] Preferably, the medium heat temperature in step (4) is 130-135°C.

[0024] The present invention provides low-furfural pecans obtained by processing using any of the above methods.

[0025] The present invention provides the following benefits: the processing method for low-furfural pecans is simple and cost-effective. The use of rosemary extract reduces the furfural content, effectively mitigating the effects of high levels of harmful substances from heat processing. The resulting rosemary extract pecans combine the flavors of pecans and rosemary, resulting in a crispy, delicious, and nutritious product. Furthermore, the low furfural content meets health requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The liquid chromatograms are of 5-hydroxymethylfurfural (HMF), furfural (FF), acetylfuran aldehyde (FMC) and 5-methylfurfural (MF).

[0027] Figure 2 The content of furfural substances generated by pecans without adding rosemary extract under different processing conditions. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, but the scope of protection claimed by the present invention is not limited to the scope described in the embodiments.

[0029] Example 1

[0030] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0031] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0032] (3) Boiling sugar: Weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C and boil for about 20 minutes, until the volume of the syrup is concentrated to about one-fourth of its original size;

[0033] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5 to 10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0034] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0035] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 1 hour, and cooling to obtain processed pecans containing low furfural substances.

[0036] The raw material ratios (by weight) used in this embodiment are as follows: 50 g white sugar / kg pecan, 10 g salt / kg pecan, and 0.20 g rosemary extract / kg pecan.

[0037] Example 2

[0038] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0039] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0040] (3) Boiling sugar: Weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C and boil for 20 minutes, until the volume of the syrup is concentrated to about one-fourth of its original size;

[0041] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5 to 10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0042] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0043] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 1 hour, and cooling to obtain processed pecans containing low furfural substances.

[0044] The raw materials (weight) used in this example are as follows: 50 g white sugar / kg pecan, 10 g salt / kg pecan, and 0.22 g rosemary extract / kg pecan.

[0045] Example 3

[0046] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0047] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0048] (3) Boiling sugar: weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C for 20 minutes, until the volume of the syrup is concentrated to about one-fourth of its original size;

[0049] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5 to 10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0050] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0051] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 1 hour, and cooling to obtain processed pecans containing low furfural substances.

[0052] The raw materials (weight) used in this example are as follows: 50 g white sugar / kg pecan, 10 g salt / kg pecan, and 0.24 g rosemary extract / kg pecan.

[0053] Example 4

[0054] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0055] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0056] (3) Boiling sugar: Weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C for 20 minutes, or until the syrup is concentrated to about a quarter of its original size;

[0057] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5-10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0058] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0059] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 0.5, 1, and 1.5 hours, and at 120, 130, and 140° C. for 1 hour, respectively, and cooling to obtain processed pecans containing low furfural substances.

[0060] The raw materials (weight) used in this embodiment are as follows: 25g / kg pecan sugar, 50g / kg pecan sugar, 75g / kg pecan sugar, 10g / kg pecan salt, and 0g / kg pecan rosemary extract.

[0061] Example 5

[0062] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0063] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0064] (3) Boiling sugar: Weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C for 20 minutes, or until the syrup is concentrated to about a quarter of its original size;

[0065] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5-10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0066] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0067] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 1 hour, and cooling to obtain processed pecans containing low furfural substances.

[0068] The raw materials used in this embodiment include, by concentration, 50 g white sugar / kg pecan, 10 g salt / kg pecan, and 0.18 g rosemary extract / kg pecan.

[0069] Example 6

[0070] (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity;

[0071] (2) removing astringency: the pecan kernels obtained in step (1) are slightly boiled in water for 30 minutes, stirring continuously during the process to completely remove astringency, and then removed and rinsed with cold water for later use;

[0072] (3) Boiling sugar: Weigh a certain amount of white sugar, salt, and rosemary extract, add 50 ml of water to dissolve and mix evenly, heat over low heat at 90°C for 20 minutes, or until the syrup is concentrated to about a quarter of its original size;

[0073] (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry continuously at medium heat at 130° C. for about 5-10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, thereby obtaining a semi-finished product.

[0074] (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 60°C for 3 hours;

[0075] (6) Baking: Baking the pecans obtained in step (5) in an oven at 130° C. for 1 hour, and cooling to obtain processed pecans containing low furfural substances.

[0076] The raw materials used in this example include, by concentration, 50 g white sugar / kg pecan, 10 g salt / kg pecan, and 0.26 g rosemary extract / kg pecan.

[0077] Experimental Example 1 Liquid Chromatography Results of Furfurals in Rosemary Extract Hickory

[0078] The method for determining the content of furfural substances in the pecans obtained in Examples 1, 2, and 3 of the present invention is as follows:

[0079] (1) Extraction: Weigh 2.00 g of sample, place it in a 10 mL centrifuge tube, add 5 mL of methanol, vortex vigorously for 2 minutes, and then centrifuge the extract at 11,000 r / min and 4°C for 10 minutes. Transfer the clear supernatant to a centrifuge tube, add 0.25 mL of Carrez I (15% potassium ferricyanide) solution and 0.25 mL of Carrez II (30% zinc sulfate) solution, let it stand for 5 minutes, wait for the protein to precipitate completely, centrifuge at 11,000 r / min and 4°C for 10 minutes, transfer the clear supernatant to a 10 mL round-bottom flask, and rotary evaporate the solvent at 52°C. The remaining residue is immediately re-dissolved with 1 mL of purified water for the next step of SPE purification and enrichment.

[0080] (2) Enrichment and purification: Before purification, activate the Oasis HLB SPE column with 5 mL of methanol and then 5 mL of purified water. Keep the SPE column moist, add the sample water extract, turn on the vacuum pump and adjust the flow rate valve so that the sample water extract passes through the SPE column at a rate of one drop per second. Add 5 mL of methanol and elute at the same rate. Discard the first 10 drops of eluent to avoid diluting the enriched eluent. Collect the eluent and perform rotary evaporation. The residue after rotary evaporation is redissolved in 1 mL of methanol and filtered through a 0.22 μm organic filter for subsequent high-performance liquid chromatography determination.

[0081] (3) High-performance liquid chromatography (HPLC) determination: chromatographic column: C18 ODS Hypersil column (250 mm × 4.6 mm, 5 μm); mobile phase: mobile phase A is acetonitrile, mobile phase B is pure water; gradient elution program: starting from 5% A and 95% B, A increases to 65% at 18 min, increases to 95% at 18–20 min, maintains 95% at 22 min, and then decreases to 5% from 23 min to end at 28 min; flow rate 0.6 mL / min; column temperature 30 °C; injection volume 5 μL; injection plate temperature 8 °C; UV detection wavelength 280 nm.

[0082] The experimental results are as follows Figure 1As shown, the retention time of HMF is 10.885 minutes, the retention time of FF is 13.692 minutes, the retention time of FMC is 15.329 minutes, and the retention time of MF is 16.716 minutes.

[0083] Experimental Example 2 Determination of furfural content in pecans with different concentrations of rosemary extract

[0084] The method for determining the content of furfural substances in the pecans obtained in Examples 1, 2, and 3 of the present invention is as follows:

[0085] (1) Extraction: Weigh 2.00 g of sample, place it in a 10 mL centrifuge tube, add 5 mL of methanol, vortex vigorously for 2 minutes, and then centrifuge the extract at 11,000 r / min and 4°C for 10 minutes. Transfer the clear supernatant to a centrifuge tube, add 0.25 mL of Carrez I (15% potassium ferricyanide) solution and 0.25 mL of Carrez II (30% zinc sulfate) solution, let it stand for 5 minutes, wait for the protein to precipitate completely, centrifuge at 11,000 r / min and 4°C for 10 minutes, transfer the clear supernatant to a 10 mL round-bottom flask, and rotary evaporate the solvent at 52°C. The remaining residue is immediately re-dissolved with 1 mL of purified water for the next step of SPE purification and enrichment.

[0086] (2) Enrichment and purification: Before purification, activate the Oasis HLB SPE column with 5 mL of methanol and then 5 mL of purified water. Keep the SPE column moist, add the sample water extract, turn on the vacuum pump and adjust the flow rate valve so that the sample water extract passes through the SPE column at a rate of one drop per second. Add 5 mL of methanol and elute at the same rate. Discard the first 10 drops of eluent to avoid diluting the enriched eluent. Collect the eluent and perform rotary evaporation. The residue after rotary evaporation is redissolved in 1 mL of methanol and filtered through a 0.22 μm organic filter for subsequent high-performance liquid chromatography determination.

[0087] (3) High-performance liquid chromatography (HPLC) determination: chromatographic column: C18 ODS Hypersil column (250 mm × 4.6 mm, 5 μm); mobile phase: mobile phase A is acetonitrile, mobile phase B is pure water; gradient elution program: starting from 5% A and 95% B, A increases to 65% at 18 min, increases to 95% at 18–20 min, maintains 95% at 22 min, and then decreases to 5% from 23 min to end at 28 min; flow rate 0.6 mL / min; column temperature 30 °C; injection volume 5 μL; injection plate temperature 8 °C; UV detection wavelength 280 nm.

[0088] The experimental results are shown in the following table:

[0089] Table 1 Content of furfural substances in pecans with different concentrations of rosemary extract

[0090]

[0091] High concentrations of furfurals are harmful to health. Data from the table show that compared to pecans without rosemary extract, the total furfural content in pecans with a rosemary extract concentration of 0.20 g / kg decreased by 35.65%, the total furfural content in pecans with a rosemary extract concentration of 0.22 g / kg decreased by 61.41%, and the total furfural content in pecans with a rosemary extract concentration of 0.24 g / kg decreased by 75.50%. The main furfural component is 5-hydroxymethylfurfural (HMF), accounting for 97.60%, 65.37%, 84.85%, and 80.06% of the total content, respectively. By inhibiting the production of HMF, rosemary extract effectively regulates the production of furfurals, and this effect increases with increasing rosemary extract concentration. The most preferred embodiment is the addition of 0.22 to 0.24 g / kg rosemary extract (RE) to pecan kernels.

[0092] Experimental Example 3 Determination of furfural content in pecans without RE addition under different processing conditions

[0093] The method for determining the content of furfural substances in the pecans obtained in Example 4 of the present invention is as follows:

[0094] (1) Extraction: Weigh 2.00 g of sample, place it in a 10 mL centrifuge tube, add 5 mL of methanol, vortex vigorously for 2 minutes, and then centrifuge the extract at 11,000 r / min and 4°C for 10 minutes. Transfer the clear supernatant to a centrifuge tube, add 0.25 mL of Carrez I (15% potassium ferricyanide) solution and 0.25 mL of Carrez II (30% zinc sulfate) solution, let it stand for 5 minutes, wait for the protein to precipitate completely, centrifuge at 11,000 r / min and 4°C for 10 minutes, transfer the clear supernatant to a 10 mL round-bottom flask, and rotary evaporate the solvent at 52°C. The remaining residue is immediately re-dissolved with 1 mL of purified water for the next step of SPE purification and enrichment.

[0095] (2) Enrichment and purification: Before purification, activate the Oasis HLB SPE column with 5 mL of methanol and then 5 mL of purified water. Keep the SPE column moist, add the sample water extract, turn on the vacuum pump and adjust the flow rate valve so that the sample water extract passes through the SPE column at a rate of one drop per second. Add 5 mL of methanol and elute at the same rate. Discard the first 10 drops of eluent to avoid diluting the enriched eluent. Collect the eluent and perform rotary evaporation. The residue after rotary evaporation is redissolved in 1 mL of methanol and filtered through a 0.22 μm organic filter for subsequent high-performance liquid chromatography determination.

[0096] (3) High-performance liquid chromatography (HPLC) determination: chromatographic column: C18 ODS Hypersil column (250 mm × 4.6 mm, 5 μm); mobile phase: mobile phase A is acetonitrile, mobile phase B is pure water; gradient elution program: starting from 5% A and 95% B, A increases to 65% at 18 min, increases to 95% at 18–20 min, maintains 95% at 22 min, and then decreases to 5% from 23 min to end at 28 min; flow rate 0.6 mL / min; column temperature 30 °C; injection volume 5 μL; injection plate temperature 8 °C; UV detection wavelength 280 nm.

[0097] The experimental results are as follows Figure 2 As shown:

[0098] Under different sucrose usage, baking time, and baking temperature conditions, the total amount of furfural substances can reach 36.32, 30.84, and 23.91 μg / g, and HMF accounts for 96.53%, 95.49%, and 94.90%, respectively, which is far higher than the furfural content in pecans obtained in Examples 1, 2, and 3, indicating that the addition of rosemary extract can effectively inhibit the formation of furfural substances in processed pecan kernels.

[0099] Experimental Example 3 RE concentration comparison experimental results

[0100] The total furfural content of the pecans obtained in Example 5 of the present invention was measured to be 26.17 μg / g, with HMF accounting for 65.72%, indicating failure to achieve effective regulation. The pecans obtained in Example 6 of the present invention had a poor flavor, with the rosemary flavor significantly masking the unique flavor of pecans. However, the pecans obtained in Examples 1, 2, and 3 had a better flavor fusion. The optimal embodiment is to add pecan kernels at a concentration of 0.22-0.24 g / kg of RE.

Claims

1. A low-furfural pecan, characterized in that: The preparation method is to add edible rosemary extract to regulate furfural substances formed during the processing of pecans, thereby obtaining a new type of pecan delicacy that is healthy, nutritious, and contains rosemary and pecan flavors.

2. The low-furfural pecan according to claim 1, wherein the pecan processing method comprises the following steps: Remove astringency: Boil the pecan kernels in water slightly, remove them and rinse with cold water for later use; Boil sugar: weigh white sugar, salt, and rosemary extract, add 45-50 ml of water to dissolve and mix evenly, heat at 80-100℃ and boil for 15-20 minutes; Stir-frying: add the de-astringent pecan kernels into the syrup, stir-fry at 130-135° C. for about 5-10 minutes, so that the syrup containing the rosemary extract evenly coats the pecan kernels to obtain a semi-finished product.

3. The low-furfural pecan according to claim 2, wherein the raw materials are as follows by weight: 45-50 g / kg of white sugar, 8-10 g / kg of salt, and 0.20-0.24 g / kg of rosemary extract.

4. The low-furfural pecan according to claim 2, wherein in the de-astringency step in the processing method, the slight boiling temperature is about 80-110°C and the duration is 25-30 minutes.

5. A method for processing pecans low in furfural, comprising the following steps: (1) Preparation: Pecan shelling, removing moldy, broken and irregular pecans, and selecting pecan kernels of similar size and integrity; (2) removing astringency: boiling the pecan kernels obtained in step (1) in water at 80-110° C. for 25-30 minutes, stirring continuously during the process to completely remove astringency, removing the kernels and rinsing with cold water for later use; (3) Boiling sugar: weigh a certain amount of white sugar, salt, and rosemary extract, add 45-50 ml of water to dissolve and mix evenly, and boil over low heat for 15-20 minutes; (4) Stir-frying: Add the de-astringent pecan kernels obtained in step (2) to the syrup, and stir-fry over medium heat for about 5 to 10 minutes, so that the syrup containing the rosemary extract obtained in step (3) evenly coats the pecan kernels. Turn off the heat until no syrup remains and a slight burnt aroma can be smelled, to obtain a semi-finished product. (5) Drying: Spread the semi-finished product obtained in step (4) evenly on a tray and dry in an oven at 50-60°C for 2-3 hours; (6) Baking: Baking the pecans obtained in step (5) in an oven at 130-135° C. for 50-60 minutes and then cooling to obtain processed pecans containing low furfural substances.

6. The method for processing low-furfural pecans according to claim 5, wherein: The raw materials used are as follows by weight: 45-50 g white sugar / kg pecan, 8-10 g table salt / kg pecan, and 0.22-0.24 g rosemary extract / kg pecan.

7. The method for producing low-furfural pecan nuts according to claim 5, wherein: The raw materials in step (3) are as follows by weight: 45-50 g / kg of white sugar per kg of pecans, 8-10 g / kg of salt per kg of pecans, and 0.20-0.24 g / kg of rosemary extract per kg of pecans.

8. The method for producing low-furfural pecans according to claim 4, wherein: The low heat temperature in step (3) is 80-100° C., and the mixture is heated and boiled for 15-20 minutes.

9. The method for producing low-furfural pecans according to claim 5, wherein: The medium heat temperature in step (4) is 130-135°C.

10. The low-furfural pecan obtained by processing according to any one of claims 5 to 9.

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