Onion seasoning oil prepared by taking rice oil as oil base and adding grape seed polyphenol

Abstract

The invention provides a method for preparing onion seasoning oil by taking rice oil as an oil base and adding grape seed polyphenol, and relates to the technical field of oil processing. According to the onion seasoning oil, water in onions is completely stirred and mixed with grape seed polyphenols, and flavor in the onions is extracted by a hot dipping method, so that the onion seasoning oil which is rich in fragrance and rich in nutrition can be obtained, and the shelf life is also obviously prolonged. The innovation point of the method is that the water-soluble grape seed polyphenol is dissolved in water through onions, the antioxidant effect is obviously improved, the method is simple in process, and the prepared onion seasoning oil is convenient to use, can enhance aroma, remove greasy taste, remove fishy smell and endow flavor and is convenient to store.

Description

Technical Field

[0001] The invention belongs to the field of food processing, relates to oil processing technology, and in particular to a method for preparing onion seasoning oil by taking rice oil as an oil base and adding grape seed polyphenol. Background Art

[0002] Onions have rich nutritional value and unique flavor. Onion oil, as a condiment or functional food raw material, has broad application prospects. However, the existing onion oil preparation methods have problems such as complex process, low oil yield, and unstable quality. At present, the more common extraction methods in China are solvent extraction, steam distillation, and supercritical CO2 extraction. At present, the consumption of onions in my country is still mainly cooking and eating fresh, with few processed products and still in the primary processing stage. There is no real deep-processed onion product, and this method is to prepare a convenient onion seasoning oil.

[0003] The fatty acid composition of rice oil is balanced, with a high content of unsaturated fatty acids. It is rich in various biologically active substances, such as oryzanol, phytosterols, squalene, vitamin E, etc., especially oryzanol, which only exists in grains. It not only has the functions of nerve regulation, lowering serum cholesterol, and preventing cardiovascular diseases, but is also an excellent natural antioxidant that can improve the oxidative stability of rice oil.

[0004] Onions are rich in nutrients and have a unique flavor, while rice oil is rich in various nutrients and has good stability. Combining onions with rice oil to prepare onion seasoning oil can not only give full play to the flavor and nutritional value of onions, but also utilize the excellent properties of rice oil to provide a new type of seasoning oil for food processing. Water-soluble grape seed polyphenols, which have important nutritional value and antioxidant effects, can be effectively dissolved in onion seasoning oil with the help of the water contained in onions. The onion seasoning oil prepared in this way not only has a strong onion flavor and the excellent properties of rice oil, but also integrates the antioxidant effect of grape seed polyphenols, providing a new type of seasoning oil with higher added value for the field of food processing. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art. Excessive moisture content in onions will not only have an adverse effect on the stability of the product during processing, but may also lead to problems in subsequent process links such as difficulty in controlling the frying temperature, affecting the quality of the oil, and prolonging the processing time. Through the innovative method of the present invention, the heat pump drying technology can effectively reduce the negative impact of excessive moisture in onions, thereby ensuring that the preparation process of onion seasoning oil is more stable. Second, as a substance with extremely high nutritional value and antioxidant effect, the insoluble property of grape seed polyphenols in oil has always been a problem that plagues the field of food processing. Traditional preparation methods make it difficult to effectively integrate grape seed polyphenols into oil, thereby limiting its application in products such as seasoning oil. The onion seasoning oil prepared by this method can be directly applied to products such as salads, soups, seasonings, etc., and has a strong cooked onion flavor. The production process is simple, suitable for large-scale production, and has a high cost performance.

[0006] The present invention solves the technical problem by adopting the following technical solutions: A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, wherein the specific steps are as follows: Select fresh, mold-free onions as raw materials, peel and wash the fresh onions, chop them into pieces with a length of 1cm-2cm, and dry them through a heat pump at 55℃ for 14 hours until the moisture content is about 10% (the initial moisture content is about 91%, and after 14 hours, the moisture content can reach less than 10%. The specific data is as follows Figure 1 As shown. ), add grape seed polyphenol (0.1g / kg), mix well and set aside. Heat the rice oil to about 180℃, mix the processed fresh onion with grape seed polyphenol, and then mix the heated rice oil with the prepared raw materials and stir evenly. After cooling for 72 hours in a sealed container, filter out the clear and transparent onion seasoning oil through a plate and frame.

[0007] The advantages and positive effects of the present invention are: The invention adopts rice oil as an oil base to prepare onion seasoning oil and adds grape seed polyphenol, fully utilizing the advantage of rice oil being rich in oryzanol and vitamin E, and improving the nutritional value of onion seasoning oil. The prepared onion seasoning oil has a strong aroma and a good taste, can be used in cooking and food processing, and improves the taste and nutritional value of food. The method of the invention has simple steps, is easy to operate, and is suitable for large-scale production. Since the production process is simple, the cost is relatively low, and the product has high nutritional value and unique flavor, it has strong competitiveness in the market and is extremely cost-effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 The moisture content changes during the onion drying process. DETAILED DESCRIPTION

[0009] The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto. Example 1

[0010] A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, wherein the specific steps are as follows: (1) Prepare 6.6 kg of fresh onions (the weight of dried onions after drying is 1 kg), 5 kg of rice oil, and 0.1 g of grape seed polyphenols (0.1 g / kg); (2) Peel the onion, wash it, cut it into 1cm-2cm pieces, and heat pump dry it at 55℃ for more than 14 hours; (3) Mix 0.1 g of grape seed polyphenols with the dried onions; (4) Pour the rice oil into a pot, heat it to 180°C, and mix the heated rice oil with onions; (5) Wait for the onion seasoning oil to cool to room temperature and seal it for 72 hours; (6) Filter the onion seasoning oil through a plate and frame filter to separate the onion residue, put the onion seasoning oil into a sealed container, and store it in a cool place.

[0011] 1. The variation patterns of acid value and peroxide value of seasoning oils stored at 70℃ for different storage days were analyzed, and the oxidation kinetic model expressions of peroxide value and acid value were established based on the Arrhenius equation to predict the shelf life.

[0012] During the storage of seasoning oil, various physical and chemical changes will occur, following certain chemical kinetics. The oil oxidation reaction is a first-order reaction in kinetics, and its reaction equation is: C=C0e ±kt Where: k is the reaction rate constant; C is the final quality characteristic; t is the storage time; C0 is the initial quality characteristic.

[0013] The effect of temperature on oil oxidation can be evaluated using the Arrhenius equation to measure the relationship between reaction rate and temperature. According to the Arrhenius equation, the rate constant k of the change of oil peroxide value is a function of temperature T:

[0014] Where: k is the reaction rate constant; Ea is the activation energy; R is the gas constant (8.3145 kJ / mol); T is the thermodynamic temperature, K; k0 is the pre-exponential factor.

[0015] Take the logarithm of both sides:

[0016] Where: k is the reaction rate constant at temperature T; k0 is the pre-exponential factor, that is, the frequency factor / min-1; Eα is the activation energy / J / mol; T is the absolute temperature / K; R is the molar gas constant, 8.314 J / mol·K.

[0017] The Arrhenius curve of peroxide value and acid value was established with the inverse of temperature (1 / T) as the abscissa and the logarithm of the corresponding reaction rate constant k (lnk) as the ordinate.

[0018] Table 1 First-order kinetic model of onion seasoning oil

[0019] Table 2 First-order kinetic model of onion seasoning oil with added grape seed polyphenols

[0020] Table 3 Second-order kinetic model of onion seasoning oil

[0021] The shelf life prediction formula of grape seed polyphenol chili seasoning oil added to the finished product is obtained by calculation: .

[0022] Table 4 Second-order kinetic model of onion seasoning oil with added grape seed polyphenols

[0023] The shelf life prediction formula of hot dip seasoning oil with grape seed polyphenols was calculated as follows: .

[0024] Table 5 Predicted shelf life of seasoning oil Example 2

[0025] A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, wherein the specific steps are as follows: (1) Prepare 3.3 kg of fresh onions (the weight of dried onions after drying is 0.5 kg), 5 kg of rice oil, and 0.05 g of grape seed polyphenols (0.1 g / kg); (2) Peel the onion, wash it, cut it into 1cm-2cm pieces, and heat pump dry it at 55℃ for 14h; (3) Mix 0.05 g of grape seed polyphenols with the dried onions; (4) Pour the rice oil into a pot, heat it to 180°C, and mix the heated rice oil with onions; (5) Wait for the onion seasoning oil to cool to room temperature and seal it for 72 hours; (6) Filter the onion seasoning oil through a plate and frame filter to separate the onion residue, put the onion seasoning oil into a sealed container, and store it in a cool place.

[0026] 1. Reduce the moisture content of onions to below 10% through heat pump drying, and set the heat pump drying parameters to 55°C and more than 14 hours.

[0027] Table 6 Changes in moisture content during onion drying process Example 3

[0028] A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, wherein the specific steps are as follows: (1) Prepare 6.6 kg of fresh onions (the weight of dried onions after drying is 1 kg), 5 kg of rice oil, and 0.1 g of grape seed polyphenols (0.1 g / kg); (2) Peel the onion, wash it, cut it into 1cm-2cm pieces, and heat pump dry it at 55℃ for 14h; (3) Mix 0.1 g of grape seed polyphenols with the dried onions; (4) Pour the rice oil into a pot, heat it to 170°C, and mix the heated rice oil with onions; (5) Wait for the onion seasoning oil to cool to room temperature and seal it for 72 hours; (6) Filter the onion seasoning oil through a plate and frame filter to separate the onion residue, put the onion seasoning oil into a sealed container, and store it in a cool place.

[0029] 1. Refer to LS / T 6119-2017 Grain and Oil Inspection - Determination of Polyphenols in Vegetable Oils - Spectrophotometric Method to determine the polyphenols in onion oil added with grape seed polyphenols. The specific steps are as follows: Use a pipette to transfer 1 mL of gallic acid working solution (4.9), water (blank) and sample solution into a graduated test tube, add 0.5 mL of Folin phenol reagent (4.5), 2 mL of 7.5% sodium carbonate solution (4.6) and 6.5 mL of water, vortex for 1 min, react in a 70°C water bath for 30 min, and use a 10 mm cuvette to measure the absorbance (A) at a wavelength of 750 nm. If the absorbance is not between 0.1 and 0.8, the sample weight should be appropriately adjusted or the solution to be tested should be diluted, and then the measurement should be repeated.

[0030] A standard curve was drawn based on the absorbance (A) of the gallic acid working solution and the gallic acid concentration of each working solution.

[0031] The polyphenol content of onion oil without added grape seed polyphenol is 30 mg / kg, and the polyphenol content of onion oil with added grape seed polyphenol is 200 mg / kg.

[0032] Comparative Example 1

[0033] A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, wherein the specific steps are as follows: (1) Prepare 6.6 kg of fresh onions (the weight of dried onions after drying is 1 kg), 5 kg of rice oil, and 0.1 g of grape seed polyphenols (0.1 g / kg); (2) Peel the onion, wash it, cut it into 1cm-2cm pieces, and heat pump dry it at 55℃ for 13h; (3) Mix 0.1 g of grape seed polyphenols with the dried onions; (4) Pour the rice oil into a pot, heat it to 180°C, and mix the heated rice oil with onions; (5) Wait for the onion seasoning oil to cool to room temperature and seal it for 72 hours; (6) Filter the onion seasoning oil through a plate and frame filter to separate the onion residue, put the onion seasoning oil into a sealed container, and store it in a cool place.

[0034] Comparative Example 2

[0035] A method for preparing onion seasoning oil using rice oil as an oil base, wherein the specific steps are as follows: (1) Prepare 6.6 kg of fresh onions (the weight of dried onions is 1 kg after drying) and 5 kg of rice oil; (2) Peel the onion, wash it, cut it into 1cm-2cm pieces, and heat pump dry it at 50℃ for 16h; (3) Pour the rice oil into a pot, heat it to 180°C, and mix the heated rice oil with onions; (4) Wait for the onion seasoning oil to cool to room temperature and seal for 72 hours; (5) Filter the onion seasoning oil through a plate and frame filter to separate the onion residue, put the onion seasoning oil into a sealed container, and store it in a cool place.

[0036] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, characterized in that: The method comprises the following steps: selecting fresh, mildew-free onions as raw materials, peeling and washing the fresh onions, chopping them into pieces with a length of 1 cm-2 cm, setting the heat pump drying parameter to 55°C for 14 hours, drying them to a moisture content of about 10%, and adding 0.1 g / kg grape seed polyphenols, mixing them for standby use. The rice oil is heated to about 180°C, the treated fresh onions are mixed with the grape seed polyphenols, and the heated rice oil is mixed with the prepared raw materials and stirred evenly. After sealing and cooling for 72 hours, the clear and transparent onion seasoning oil is filtered out through a plate frame.

2. The method according to claim 1, characterized in that The onion moisture content needs to be dried to below 10%, and the water-soluble grape seed polyphenols need to be dissolved in oil.

3. A method for preparing onion seasoning oil by using rice oil as an oil base and adding grape seed polyphenols, characterized in that: The onion seasoning oil is prepared by the method according to claim 1 or 2.

Images