All-component peanut butter and preparation method thereof

Abstract

The invention provides all-component peanut butter and a preparation method thereof, and relates to the technical field of food processing. According to the method, the bioactive substances and the proteins in the peanut shells and the peanut coats can be extracted by combining enzymolysis treatment with an alkali-solution and acid-precipitation method and alcohol precipitation treatment without adding other organic solvents, so that effective utilization of the peanut shells and the peanut coats is achieved, high-value utilization of peanuts is achieved, and the method is suitable for industrial production. Meanwhile, the safety in the food processing process is also ensured.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, in particular to a full-component peanut butter and a preparation method thereof. Background Art

[0002] Peanuts are one of the world's four most important oil crops. Peanut oil is not only produced from peanuts, but peanut butter is also a popular product. However, the peanut butter processing process produces a large number of byproducts, including peanut shells and skins, which account for approximately one-third of the peanut weight. Studies have shown that adding peanut shells and skins directly to peanut butter increases the stability of the peanut butter, but also increases negative sensory perceptions such as excessive bitterness and woody flavors. Therefore, peanut shells and skins, as low-value byproducts, are either discarded or used as a minor ingredient in animal feed after they are removed.

[0003] However, other studies have shown that peanut shells and skins are rich in protein and dietary fiber, which have antioxidant and blood sugar-lowering properties. They also contain many edible functional compounds, such as polyphenols and flavonoids, which have anti-inflammatory and antioxidant effects. Therefore, effectively utilizing peanut shells and skins in peanut butter processing has become a key area for increasing the value of peanuts. Current research tends to use organic solvents to extract bioactive compounds from peanut shells and skins, but the presence of organic solvents reduces safety during food processing.

[0004] Therefore, it is urgent to provide a solution to solve the above problems. Summary of the Invention

[0005] The present invention aims to provide a full-component peanut butter and a preparation method thereof. The method extracts bioactive substances and proteins in peanut shells and peanut skins through enzymatic hydrolysis combined with alkali dissolution, acid precipitation and alcohol precipitation, thereby realizing the utilization of full-component peanuts.

[0006] In a first aspect, the present invention provides a full-component peanut butter, which includes 4%-10% of an oil phase, 1%-3% of protein, 1%-3% of soluble dietary fiber, 1%-3% of white sugar, 1%-3% of salt and 78%-92% of peanut kernels.

[0007] Using peanut oil to extract bioactive substances in peanut shells and peanut skins can avoid the addition of other organic solvents and ensure safety during food processing.

[0008] In a second aspect, the present invention provides a method for preparing a full-component peanut butter, comprising the following steps:

[0009] S1. Mix peanut shells and peanut skins with water and peanut oil, add cellulase for enzymatic hydrolysis, and centrifuge to obtain an oil phase, an aqueous phase, and a precipitate;

[0010] S2, dissolving the precipitate in the aqueous phase, treating with alkali dissolution and acid precipitation to obtain protein and supernatant, and taking the supernatant for alcohol precipitation to obtain soluble dietary fiber;

[0011] S3. Grinding the oil phase, protein and soluble dietary fiber obtained above with roasted peanut kernels, sugar and salt to obtain a full-component peanut butter.

[0012] Optionally, the peanut shells and peanut skins in step S1 need to be pre-crushed and passed through a 60-200 mesh sieve before being mixed with water and oil.

[0013] Optionally, in step S1, the mixing ratio of peanut shells and peanut skins, water, and peanut oil is 1 g: (5-20) mL: (2-10) mL.

[0014] Optionally, the enzymatic hydrolysis in step S1 includes: adding cellulase and performing enzymatic hydrolysis for 2 h to 4 h at a temperature of 40° C. to 70° C. and a pH of 3.0 to 6.0.

[0015] Optionally, the cellulase accounts for 0.1%-0.5% of the mass of the peanut shells and peanut skins.

[0016] Enzymatic hydrolysis can promote the release of bioactive substances and proteins in peanut shells and peanut skins, achieve efficient transfer of bioactive substances from peanut shells and peanut skins to peanut oil, and at the same time improve the protein extraction rate.

[0017] Optionally, the centrifugation in step S1 includes: centrifuging at 5000 rpm-6000 rpm for 10 min-15 min.

[0018] Optionally, the alkali dissolution and acid precipitation treatment in step S2 includes:

[0019] After the precipitate is dissolved in the aqueous phase, sodium hydroxide solution is added to adjust the pH of the system to 8.0-10.0, and the mixture is extracted at a temperature of 30-60°C for 1-4 hours, and the supernatant is collected by centrifugation;

[0020] A hydrochloric acid solution is added to the supernatant 1 to adjust the pH of the system to 3.0-5.0, and the mixture is precipitated at a temperature of 0° C.-30° C. for 1 h-3 h, and freeze-dried to obtain protein and supernatant 2.

[0021] Optionally, the concentration of the sodium hydroxide solution and the hydrochloric acid solution is 0.1 mol / L.

[0022] Optionally, the alcohol precipitation treatment in step S2 includes:

[0023] The supernatant is vacuum concentrated to 1 / 4-1 / 3 of the original volume, and then 4-6 times the volume of ethanol is added for precipitation for 20h-24h, and the precipitate is obtained by centrifugation. The precipitate is dried to obtain soluble dietary fiber powder.

[0024] Optionally, the drying includes drying in an oven at 60° C.-80° C. for 1 hour-2 hours.

[0025] In a third aspect, the present invention provides an application of the above-mentioned preparation method in processing peanut butter using whole-component peanuts.

[0026] When the preparation method is applied to the processing of peanut butter, peanut shells and peanut skins can be effectively utilized, thereby achieving high-value utilization of peanuts. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly introduce the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0028] Figure 1 The method is to determine the yield of protein, polyphenols and soluble dietary fiber in the peanut shells and peanut skin powders of Examples 1 to 4 in the performance test of the present invention;

[0029] Figure 2 This is the determination of the protein, polyphenol and soluble dietary fiber contents in the peanut butters prepared in Examples 1 to 4 and Comparative Examples 1 to 4 in the performance test of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described through the following examples in conjunction with the accompanying drawings. However, the following examples are illustrative and are only used to specifically describe the present invention, rather than to limit the present invention.

[0031] The invention provides a full-component peanut butter, which comprises 4%-10% of an oil phase, 1%-3% of protein, 1%-3% of soluble dietary fiber, 1%-3% of white sugar, 1%-3% of salt and 78%-92% of peanut kernels.

[0032] The present invention also provides a method for preparing a full-component peanut butter, comprising the following steps:

[0033] S1. Mix peanut shells and peanut skins with water and peanut oil, add cellulase for enzymatic hydrolysis, and centrifuge to obtain an oil phase, an aqueous phase, and a precipitate;

[0034] S2, dissolving the precipitate in the aqueous phase, treating with alkali dissolution and acid precipitation to obtain protein and supernatant, and taking the supernatant for alcohol precipitation to obtain soluble dietary fiber;

[0035] S3. Grinding the oil phase, protein and soluble dietary fiber obtained above with roasted peanut kernels, sugar and salt to obtain a full-component peanut butter.

[0036] In some embodiments, when performing step S1, the peanut shells and peanut skins are pre-crushed and passed through a 60-200 mesh sieve before being mixed with water and oil.

[0037] In some embodiments, when performing step S1, the mixing ratio of peanut shells and peanut skins, water, and peanut oil is 1 g: (5-20) mL: (2-10) mL.

[0038] In some embodiments, when performing step S1, the enzymatic hydrolysis includes: adding cellulase and performing enzymatic hydrolysis for 2 h to 4 h at a temperature of 40° C. to 70° C. and a pH of 3.0 to 6.0.

[0039] In some embodiments, when performing step S1, the cellulase accounts for 0.1%-0.5% of the weight of the peanut shells and peanut skins.

[0040] In some embodiments, when performing step S1, the centrifugation includes: centrifuging at 5000 rpm-6000 rpm for 10 min-15 min.

[0041] In fact, when executing step S2, the following sub-steps are included:

[0042] S2.1. Dissolve the precipitate in the aqueous phase, add sodium hydroxide solution to adjust the pH of the system to 8.0-10.0, extract at 30-60°C for 1-4 hours, and centrifuge to obtain the supernatant.

[0043] S2.2. Add hydrochloric acid solution to the supernatant 1 to adjust the pH of the system to 3.0-5.0, precipitate at 0°C-30°C for 1-3 hours, and lyophilize to obtain protein and supernatant 2;

[0044] S2.3. After vacuum concentrating the supernatant to 1 / 4-1 / 3 of the original volume, add 4-6 times the volume of ethanol and precipitate for 20h-24h, centrifuge to obtain a precipitate, and dry the precipitate to obtain soluble dietary fiber powder.

[0045] In some embodiments, when performing step S2.1 and step S2.2, the concentration of the sodium hydroxide solution and the hydrochloric acid solution is 0.1 mol / L.

[0046] In some embodiments, when performing step S2.3, the drying includes drying in an oven at 60° C.-80° C. for 1 hour-2 hours.

[0047] The present invention also provides an application of the preparation method in processing peanut butter using whole-component peanuts.

[0048] The cellulase used in the examples of the present invention was purchased from Novozymes (China) Biotechnology Co., Ltd.

[0049] Example 1

[0050] Example 1 of the present invention provides a method for preparing full-component peanut butter, wherein the peanut variety selected is Jihua No. 19, the peanut weight is 223.5 grams, and the peanut skin is light pink, comprising the following steps:

[0051] S1. Shell the peanuts, select full-grained, pest-free peanut kernels for roasting, peel the peanut kernels after cooling, crush the peanut skins and shells, and pass them through a 150-mesh sieve to obtain a mixed powder. Mix 10 g of the mixed powder with 100 mL of water and 50 mL of peanut oil, add 0.08 g of cellulase, and perform enzymatic hydrolysis at 50° C. and pH 3.5 for 2 h. Then, centrifuge at 5500 rpm for 10 min to obtain an upper oil phase, an intermediate aqueous phase, and a precipitate.

[0052] S2.1. Redissolve the precipitate in the aqueous phase, adjust the pH of the system to 8.5 with 0.1 mol / L sodium hydroxide, perform alkaline dissolution at 40°C for 2 h, and then centrifuge at 8000 rpm for 10 min to obtain the peanut shell and peanut skin residue and supernatant.

[0053] S2.2. Adjust the pH of the supernatant 1 to 3.5 with 0.1 mol / L hydrochloric acid, subject to acid precipitation at 20°C for 1 hour, and centrifuge at 8000 rpm for 10 minutes. Freeze-dry to obtain the protein and supernatant 2.

[0054] S2.3. Concentrate the supernatant to 50 mL in vacuo, add 200 mL of anhydrous ethanol, and precipitate for 24 h. Centrifuge at 4000 rpm for 10 min to obtain a precipitate. Dry the precipitate in an oven at 60°C for 2 h to obtain soluble dietary fiber powder.

[0055] S3. Grind 8 g of the oil phase, 3 g of protein, and 2 g of soluble dietary fiber obtained in the above steps with 2 g of white sugar, 1 g of salt, and 84 g of roasted peanut kernels, and homogenize to obtain a full-component peanut butter.

[0056] Example 2

[0057] Example 2 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 1 in that:

[0058] The peanut variety used is Fenghua No. 1, with a peanut weight of 240 grams and a light pink skin.

[0059] The amount of peanut oil added in step S1 is 30 mL;

[0060] The temperature of the enzymatic hydrolysis in step S1 is 55°C;

[0061] In step S2.1, the pH is adjusted to 9.0 with sodium hydroxide, and the temperature of the alkaline dissolution is 45°C;

[0062] The temperature of the acid precipitation in step S2.2 is 15°C;

[0063] In step S3, the amount of protein added is 2 g, the amount of white sugar added is 1 g, and the amount of peanuts added is 86 g.

[0064] Example 3

[0065] Example 3 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 1 in that:

[0066] The peanut variety used is Heifeng No. 1, with a peanut weight of 250 grams and black peanut skin.

[0067] The sieve mesh size of the peanut skins and shells crushed in step S1 is 100 mesh;

[0068] In step S1, the amount of water added is 150 mL, the amount of peanut oil added is 100 mL, and the amount of cellulase added is 0.06 g;

[0069] In step S1, the enzymatic hydrolysis temperature is 60°C, the pH during enzymatic hydrolysis is 4.5, and the enzymatic hydrolysis time is 3 hours;

[0070] In step S2.1, the pH is adjusted to 9.0 with sodium hydroxide, and the temperature of the alkaline dissolution is 45°C;

[0071] In step S2.2, the acid precipitation temperature is 15°C and the acid precipitation time is 2 hours;

[0072] In step S3, the amount of oil phase added is 6 g, the amount of protein added is 1 g, the amount of white sugar added is 1 g, and the amount of peanuts added is 89 g.

[0073] Example 4

[0074] Example 4 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 1 in that:

[0075] The peanut variety used is four red peanuts, with a peanut weight of 120 grams and red peanut skin;

[0076] The sieve mesh size of the peanut skins and shells crushed in step S1 is 100 mesh;

[0077] In step S1, the amount of water added is 100 mL, the amount of peanut oil added is 80 mL, and the amount of cellulase added is 0.07 g;

[0078] In step S1, the enzymatic hydrolysis temperature is 65°C and the enzymatic hydrolysis time is 3 hours;

[0079] In step S2.1, the pH is adjusted to 9.0 with sodium hydroxide, and the temperature of the alkaline dissolution is 55°C;

[0080] In step S2.2, the acid precipitation temperature is 15°C and the acid precipitation time is 2 hours;

[0081] In step S3, the amount of oil phase added is 7 g, the amount of protein added is 2 g, and the amount of peanuts added is 86 g.

[0082] Comparative Example 1

[0083] Comparative Example 1 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 1 in that:

[0084] No enzymatic hydrolysis is performed in step S1;

[0085] The acid precipitation, alkali dissolution and alcohol precipitation treatments in steps S2.1 to S2.3 are not performed;

[0086] In step S3, no protein or soluble dietary fiber is added.

[0087] In step S3, untreated peanut oil is added;

[0088] The mass of peanuts added in step S3 is 89 g.

[0089] Comparative Example 2

[0090] Comparative Example 2 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 2 in that:

[0091] No enzymatic hydrolysis is performed in step S1;

[0092] The acid precipitation, alkali dissolution and alcohol precipitation treatments in steps S2.1 to S2.3 are not performed;

[0093] In step S3, no protein or soluble dietary fiber is added.

[0094] In step S3, untreated peanut oil is added;

[0095] The mass of peanuts added in step S3 is 90 g.

[0096] Comparative Example 3

[0097] Comparative Example 3 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 3 in that:

[0098] No enzymatic hydrolysis is performed in step S1;

[0099] The acid precipitation, alkali dissolution and alcohol precipitation treatments in steps S2.1 to S2.3 are not performed;

[0100] In step S3, no protein or soluble dietary fiber is added.

[0101] In step S3, untreated peanut oil is added;

[0102] The mass of peanuts added in step S3 is 92 g.

[0103] Comparative Example 4

[0104] Comparative Example 4 of the present invention provides a method for preparing a full-component peanut butter, which differs from Example 4 in that:

[0105] No enzymatic hydrolysis is performed in step S1;

[0106] The acid precipitation, alkali dissolution and alcohol precipitation treatments in steps S2.1 to S2.3 are not performed;

[0107] In step S3, no protein or soluble dietary fiber is added.

[0108] In step S3, untreated peanut oil is added;

[0109] The mass of peanuts added in step S3 is 90 g.

[0110] Performance testing

[0111] (1) Protein yield of peanut shells and peanut powder and protein content in peanut butter

[0112] The protein yield of peanut shells and peanut skin powder in Examples 1 to 4 was calculated using the Kjeldahl method (GB 5009.5-2016 National Food Safety Standard - Determination of Protein in Food - Method 1). The results are as follows: Figure 1 The protein content of the peanut butter prepared in Examples 1 to 4 and Comparative Examples 1 to 4 was measured, and the results were as shown. Figure 2 shown.

[0113] (2) Determination of polyphenol yield in peanut shells and peanut skin powder and polyphenol content in peanut butter

[0114] 1 g of the peanut shell and peanut skin powder in Examples 1 to 4 and 1 g of the peanut butter prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were weighed and mixed with 30 mL of 70% ethanol solution, and then ultrasonicated at 47° C. and 240 W for 15 min. The supernatant was collected after centrifugation at 6000 rpm for 15 min. The precipitate was dissolved in 50 mL of 80% ethanol solution, ultrasonicated a second time, and centrifuged to obtain supernatant 2. Supernatant 1 and supernatant 2 were mixed, 1 mL was taken into a 10 mL centrifuge tube, 0.5 mL of forlin phenol was added, and the mixture was shaken and reacted for 3 min. Then, 2 mL of 7.5% (w / v) sodium carbonate solution and 6.5 mL of distilled water were added, and the mixture was shaken and reacted for 1 min. After the mixture was placed in the dark for 1 h, the absorbance at 765 nm was measured using an ultraviolet spectrophotometer, which represents the polyphenol yield of the peanut shell and peanut skin powder and the polyphenol content in the peanut butter. The results are as follows: Figure 1 and Figure 2 shown.

[0115] (2) Determination of soluble dietary fiber yield from peanut shells and peanut skin powder and soluble dietary fiber content in peanut butter

[0116] The soluble dietary fiber yields of peanut shells and peanut skin powders in Examples 1 to 4 were calculated using the GB 5009.88-2023 National Food Safety Standard for the Determination of Dietary Fiber in Food. The results are as follows: Figure 1 As shown; the soluble dietary fiber content in the peanut butter prepared in Examples 1 to 4 and Comparative Examples 1 to 4 was measured, and the results were as follows Figure 2 shown.

[0117] The results showed that the whole-component peanut butter prepared by processing different varieties of peanuts using the method provided by the present invention had a polyphenol content increased by about 300%, a soluble dietary fiber content increased by about 400%, and a slightly increased protein content compared to the whole-component peanut butter processed by conventional methods.

[0118] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations of these embodiments are possible. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as set forth in the appended claims. Furthermore, the invention described herein is susceptible to other embodiments and may be practiced or implemented in a variety of ways.

Claims

1. A full-component peanut butter, characterized in that: The peanut butter comprises 4%-10% of oil phase, 1%-3% of protein, 1%-3% of soluble dietary fiber, 1%-3% of white sugar, 1%-3% of salt and 78%-92% of peanut kernels.

2. A method for preparing a full-component peanut butter, characterized in that: The following steps are involved: S1. Mix peanut shells and peanut skins with water and peanut oil, add cellulase for enzymolysis, and centrifuge to obtain an oil phase, an aqueous phase and a precipitate; S2, dissolving the precipitate in water, treating it by alkali dissolution and acid precipitation to obtain protein and supernatant, taking the supernatant and performing alcohol precipitation to obtain soluble dietary fiber; S3. Grinding the oil phase, protein and soluble dietary fiber obtained above with roasted peanut kernels, sugar and salt to obtain full-component peanut butter.

3. The preparation method according to claim 2, characterized in that: In step S1, the peanut shells and peanut skins need to be crushed in advance and passed through a 60-200 mesh sieve before being mixed with water and oil.

4. The preparation method according to claim 2, characterized in that: In step S1, the mixing ratio of peanut shells and peanut skins, water and peanut oil is 1 g: (5-20) mL: (2-10) mL.

5. The preparation method according to claim 2, characterized in that: The enzymatic hydrolysis in step S1 includes: adding cellulase and performing enzymatic hydrolysis for 2h-4h at a temperature of 40°C-70°C and a pH of 3.0-6.0; the cellulase accounts for 0.1%-0.5% of the mass of the peanut shell and peanut skin.

6. The preparation method according to claim 2, characterized in that: The centrifugation in step S1 includes: centrifuging at 5000 rpm-6000 rpm for 10 min-15 min.

7. The preparation method according to claim 2, characterized in that: The alkali dissolution and acid precipitation treatment in step S2 includes: After the precipitate is dissolved in the aqueous phase, sodium hydroxide solution is added to adjust the pH of the system to 8.0-10.0, and the mixture is extracted at a temperature of 30°C-60°C for 1h-4h, and centrifuged to obtain a supernatant; A hydrochloric acid solution is added to the supernatant 1 to adjust the pH value of the system to 3.0-5.0, and the mixture is precipitated at a temperature of 0° C.-30° C. for 1 h-3 h, and then freeze-dried to obtain protein and supernatant 2.

8. The preparation method according to claims 2 and 7, characterized in that: The alcohol precipitation treatment in step S2 includes: The supernatant is vacuum concentrated to 1 / 4-1 / 3 of the original volume, and then 4-6 times the volume of ethanol is added for precipitation for 20h-24h, and the precipitate is obtained by centrifugation, and the precipitate is dried to obtain soluble dietary fiber powder.

9. Use of the whole-ingredient peanut butter according to claim 1 or the whole-ingredient peanut butter prepared by the preparation method according to any one of claims 2 to 8 in processing peanut butter using whole-ingredient peanuts.

Images