阅读说明：本技术 一种提高西兰花营养品质的烹饪方法 (Cooking method for improving nutrition quality of broccoli ) 是由 周鹏 樊田利 刘若男 刘冬梅 王凤丽 于 2021-01-28 设计创作，主要内容包括：本发明公开了一种提高西兰花营养品质的烹饪方法,属于食品加工技术领域。本发明所述的方法包括如下步骤：(1)将西兰花修剪成规格统一的小花；(2)将步骤(1)处理后的西兰花摆放在蒸屉上；(3)在蒸锅内加水煮沸,之后将步骤(2)的蒸屉放置在蒸锅上,蒸制西兰花,其中蒸制的功率为100-2100W；待西兰花成熟,停止烹饪。本发明的方法中随着蒸制功率的增大,a*值呈现下降的趋势,即绿色强度增加；叶绿素、类胡萝卜素的含量整体呈现上升趋势；抗坏血酸和总酚含量越高,抗氧化活性越高；即本发明的方法不仅可以明显增加西兰花营养物质的保存率,也有效保存了西兰花的绿色。(The invention discloses a cooking method for improving the nutritional quality of broccoli, and belongs to the technical field of food processing. The method comprises the following steps: (1) cutting broccoli into small flowers with uniform specification; (2) placing the broccoli treated in the step (1) on a steaming drawer; (3) adding water into a steamer for boiling, then placing the steamer tray in the step (2) on the steamer for steaming broccoli, wherein the steaming power is 100-; and stopping cooking when the broccoli is mature. In the method, as the steaming power is increased, the a value shows a descending trend, namely the green intensity is increased; the contents of chlorophyll and carotenoid integrally show an increasing trend; the higher the ascorbic acid and total phenol content is, the higher the antioxidant activity is; the method of the invention not only can obviously increase the preservation rate of nutrient substances of the broccoli, but also can effectively preserve the green color of the broccoli.)

1. A cooking method for improving the nutritional quality of broccoli is characterized in that steam is adopted in the method, wherein the power adopted in the steam process is 100-2100W.

2. Method according to claim 1, characterized in that it comprises the following steps:

(1) cutting broccoli into small flowers with uniform specification;

(2) placing the broccoli treated in the step (1) on a steaming drawer;

(3) adding water into a steamer for boiling, then placing the steamer tray in the step (2) on the steamer for steaming broccoli, wherein the steaming power is 100-; and stopping cooking when the broccoli is mature.

3. The method according to claim 1 or 2, wherein step (1) is to trim broccoli into florets having a crown diameter of 3.5-4.5cm, a stem diameter of 1.0-1.5cm, and a small stem length of 1.0-1.5 cm.

4. The method according to any one of claims 1 to 3, wherein step (2) is performed in a circular arrangement on the steam drawer.

5. The method according to any one of claims 1 to 4, wherein the nutritional qualities include a value of a, chlorophyll, carotenoids, total phenolic compounds, ascorbic acid.

6. The method according to any one of claims 1 to 5, wherein the ripening in step (3) is no significant difference between the hardness value of broccoli and the hardness value of 1600W steamed for 3.5 min.

7. The method according to any one of claims 1 to 6, wherein the steaming in step (3) is performed using an induction cooker.

8. The method according to any one of claims 1-7, wherein the Michelia floribunda after trimming in step (1) is dried and placed.

9. Mature broccoli with good nutritional quality prepared by the method of any one of claims 1 to 8.

10. A steaming method for preparing broccoli with high antioxidant activity is characterized by comprising the following steps:

(1) pruning broccoli into florets with the diameter of corolla of 3.5-4.5cm, the diameter of scape of 1.0-1.5cm and the length of scape of florets of 1.0-1.5 cm; wiping water;

(2) placing the broccoli treated in the step (1) on a steaming drawer in a circular manner;

(3) adding water into a steamer for boiling, then placing the steamer tray in the step (2) on the steamer for steaming broccoli, wherein the steaming power is 1000-; and stopping cooking when the broccoli is mature.

Technical Field

The invention relates to a cooking method for improving the nutritional quality of broccoli, belonging to the technical field of food processing.

Background

Cruciferae plants are highly popular among consumers due to their high nutritional value, and broccoli, which is known as "vegetable crown", is the top place of vegetables of the same kind. China is the largest producer of broccoli, followed by india, usa, spain, mexico and italy. Over the past decade, broccoli has been consumed several times, mainly because of the awareness that its abundance of chlorophyll, carotenoids, polyphenols, ascorbic acid, and glucosinolates, among others, can reduce the incidence of many chronic diseases, including cancer, cardiovascular disease, neurodegenerative disease, metabolic disorders and their pathological sequelae, and autoimmune dysfunction. According to the cooking tradition, broccoli is subjected to heat treatment in different ways before eating.

Disclosure of Invention

[ problem ] to

The beneficial effects of the heat treatment include: but are not limited to, enhancing food safety and digestibility by inactivating microorganisms, enhancing nutrient extractability and bioavailability by softening the food matrix. However, the simultaneous heat treatment can have undesirable consequences, such as thermal degradation of the nutrient substances, formation of toxic compounds, and a reduction in the color acceptance.

[ solution ]

In order to solve at least one problem, the invention provides a cooking method for improving the nutritional quality of broccoli, which effectively preserves the nutritional quality of the broccoli by high-steam steaming and realizes balance of color and nutrition.

The first purpose of the invention is to provide a cooking method for improving the nutritional quality of broccoli, which adopts steam steaming, wherein the power adopted in the steaming process is 100-2100W.

In one embodiment of the present invention, the power used in the steaming process is 1000-1600W, and more preferably 1600W.

In one embodiment of the invention, the method comprises the steps of:

(1) cutting broccoli into small flowers with uniform specification;

(2) placing the broccoli treated in the step (1) on a steaming drawer;

(3) adding water into a steamer for boiling, then placing the steamer tray in the step (2) on the steamer for steaming broccoli, wherein the steaming power is 100-; and stopping cooking when the broccoli is mature.

In one embodiment of the present invention, step (1) is to trim broccoli into florets with a crown diameter of 3.5-4.5cm, a stem diameter of 1.0-1.5cm and a small stem length of 1.0-1.5 cm.

In one embodiment of the present invention, step (2) is performed by placing the steaming tray in a circular arrangement.

In one embodiment of the present invention, the steaming in step (3) is performed by using an induction cooker.

In one embodiment of the invention, the nutritional qualities include a value, chlorophyll, carotenoids, total phenolic compounds, ascorbic acid.

In one embodiment of the invention, the Michelia floribunda after trimming in step (1) needs to be wiped to remove water and then placed.

In one embodiment of the present invention, the ripening in step (3) is no significant difference between the hardness value of broccoli and the hardness value of 1600W steamed for 3.5min (97.36 ± 10.68).

The second purpose of the invention is to prepare the mature broccoli with good nutritional quality by the method.

A third object of the present invention is a steaming method for preparing broccoli having high antioxidant activity, the method comprising the steps of:

(1) pruning broccoli into florets with the diameter of corolla of 3.5-4.5cm, the diameter of scape of 1.0-1.5cm and the length of scape of florets of 1.0-1.5 cm; wiping water;

(2) placing the broccoli treated in the step (1) on a steaming drawer in a circular manner;

(3) adding water into a steamer for boiling, then placing the steamer tray in the step (2) on the steamer for steaming broccoli, wherein the steaming power is 1000-; and stopping cooking when the broccoli is mature.

In one embodiment of the present invention, the steaming power in step (3) is 1600W.

[ advantageous effects ]

(1) The method can effectively preserve the green appearance of the broccoli, and the content of the chlorophyll can reach more than 125.11 +/-3.40 mg/100g of dry basis and can reach 146.38 +/-3.26 mg/100g of dry basis; the carotenoid content can reach more than 32.74 +/-1.28 mg/100g dry basis and can reach 38.27 +/-0.79 mg/100g dry basis.

(2) The method can obviously reduce the loss of nutrient substances, and when the broccoli steamed at different powers reaches the same maturity, the a value shows a descending trend along with the increase of the steaming power, namely the green strength is increased; the contents of chlorophyll and carotenoid integrally show an increasing trend; the total phenol content of broccoli steamed at different powers is higher than that of fresh unprocessed broccoli, and the higher the steaming power is, the higher the total phenol content is (773 mg/100g dry base and 868mg/100g dry base for 100W and 1600W respectively); the content of the ascorbic acid after steaming is reduced, but more ascorbic acid content is kept compared with that of 1600W and 100W (the 100W and 1600W are 669.31mg/100g dry basis and 821.76mg/100g dry basis respectively); the oxidation resistance is closely related to the total phenol content and the ascorbic acid content, and the higher the steaming power is, the higher the ascorbic acid and total phenol content is, and the higher the oxidation resistance activity is. Therefore, the larger the steam amount is, the greener the surface color of the broccoli is, the higher the retention rate of the contents of chlorophyll, carotenoid, total phenol and ascorbic acid is, and the higher the corresponding antioxidant activity is.

(3) The method can indirectly represent the size of the steam quantity through the change of the nutrition quality, namely the broccoli reaching the same maturity is steamed, and the higher the retention rate of the nutrient substances is, the larger the corresponding steam quantity is; the more nutrients are lost, the smaller the corresponding amount of steam.

Drawings

FIG. 1 shows how broccoli florets are placed on a steaming drawer.

FIG. 2 shows the effect of different steaming powers on the color of broccoli when steaming to the same maturity.

FIG. 3 is a graph showing the effect on the total phenol content of broccoli when different steaming powers were used to achieve the same maturity.

FIG. 4 is a graph showing the effect of different steaming power on the ascorbic acid content of broccoli when the same maturity is achieved.

Detailed Description

The following description of the preferred embodiments of the present invention is provided for the purpose of better illustrating the invention and is not intended to limit the invention thereto. The maturity in the examples is that the hardness value of broccoli and the hardness value of 1600W steamed for 3.5min (97.36 +/-10.68) have no significant difference.

Test method

1. Method for determining color difference: the color space was chosen as CIE L, a, b using a Coriolis Minnetda CM-700d colorimeter. The color of each small flower crown of broccoli was randomly measured, and data L, a, b were read, wherein the value of L represents the brightness (black 0, white 100), the value of a represents the red-green value (red >0, green <0), and the value of b represents the yellow-blue value (yellow >0, blue <0), and a was used to characterize the change in color of broccoli during processing.

2. Method for determining texture: cooling broccoli taken out from a steamer to room temperature, cutting 1cm of small stems of the broccoli, measuring the central hardness value of the broccoli by adopting TA.XTPLUS of British SMS company and selecting a puncture probe P/2N with the diameter of 2mm, wherein the measurement parameters are the speed before measurement of 2mm/s, the speed during measurement of 1mm/s, the speed after measurement of 1mm/s, the pressing distance of 5mm and the trigger force of 5 g.

3. Method for determining total phenol content:

extraction of broccoli polyphenol: taking 0.2g of freeze-dried and ground broccoli, putting the broccoli into a 50mL triangular flask, adding 20mL of ethanol solution with the volume fraction of 60%, leaching for 1h in a sealed water bath (55 ℃), filtering by qualitative filter paper to a 10mL brown EP tube for later use.

Preparation of a gallic acid standard curve: accurately weighing 0.1000g of gallic acid, dissolving in a 100mL volumetric flask, metering to a certain volume with 60% ethanol solution, shaking up (1000 mug/mL, for use in preparation at present); transferring 1.0mL, 2.0mL, 4.0mL and 5.0mL into a 100mL volumetric flask, and diluting with 60% ethanol to constant volume to a scale mark to obtain gallic acid working solution: 10. mu.g/mL, 20. mu.g/mL, 30. mu.g/mL, 40. mu.g/mL, 50. mu.g/mL, 60. mu.g/mL, 70. mu.g/mL, 80. mu.g/mL, 90. mu.g/mL, 100. mu.g/mL, 110. mu.g/mL, 120. mu.g/mL.

4. And (3) measuring the polyphenol content: transferring 2.5mL of the extractive solution, gallic acid working solution, and 60% ethanol into 25mL test tube with plug, adding 10mL 10% Folin phenol reagent, shaking, reacting for 3-8min, adding 10 mL7.5% NaCO₃The solution was made to a volume of 25mL with deionized water, protected from light at room temperature for 60min, its absorbance value was measured at 765nm and taken into a standard curve to calculate the polyphenol content (mg/100g dry basis).

4. Method for determining ascorbic acid content:

sample extraction: weighing 0.2g broccoli powder into a 50mL lightproof centrifuge tube, homogenizing with 40mL20 g/mL metaphosphoric acid solution for 1min, transferring into a 50mL brown volumetric flask, and fixing the volume. Shaking, transferring all the mixture into a 50mL centrifuge tube, performing ultrasonic extraction for 5min, and centrifuging at 5000r/min for 10 min. Accurately sucking 20mL of supernatant into a 50mL centrifuge tube, adding 10mL of 40 g/L-cysteine solution, adjusting the pH to 7.0-7.2 by using 100g/L trisodium phosphate solution, and oscillating for 5min at 200 times/min. And adjusting the pH value to 2.5-2.8 by using phosphoric acid, completely transferring the test solution into a 50mL volumetric flask by using water, and fixing the volume to the scale. After mixing, the test solution is taken out, filtered by a 0.45 mu m water phase filter membrane and then put into a brown liquid phase bottle for HPLC detection.

5. Chlorophyll and carotenoid content determination: refer to "spectrophotometry for measuring chlorophyll content in fruits, vegetables and products thereof" NY/T3082-2017.

6. Determination of DPPH radical scavenging Rate:

the determination method comprises the following steps: respectively weighing 0.1g of broccoli freeze-dried powder in a 50mL centrifuge tube, adding 10mL of 60% ethanol solution for homogenizing (mass fraction is 2%), performing ultrasonic extraction at 60 ℃ for 30min, taking out, centrifuging for 3min under the condition of 7800r/min, and removing the supernatant for later use;

DPPH free radical clearance determination: diluting the supernatant with 60% ethanol to obtain 0.25% sample solution, adding 0.5mL of 0.2mmol/L DPPH solution (dissolved in 100% ethanol) into 0.5mL of the sample solution, oscillating, reacting at room temperature in the dark for 30min, and measuring the light absorption value (A) of the sample at 517nm_sample)；Blank set is absorbance at 517nm of 0.5mL of 100% ethanol and 0.5mL of sample solution (A)_blank) (ii) a Control group absorbance at 517nm of 0.5mL DPPH solution and 0.5mL 100% ethanol (A)_control). The formula for calculating the DPPH scavenging ability of the sample solution is as follows (1):

DPPH free radical clearance (%) [1- (Asample-Ablank)/(Acontrol-Ablank) ] × 100 (1)

Example 1

A cooking method for improving the nutritional quality of broccoli comprises the following steps:

(1) pruning broccoli into florets with the diameter of corolla of 3.5-4.5cm, the diameter of scape of 1.0-1.5cm and the length of scape of florets of 1.0-1.5 cm; wiping water;

(2) placing the broccoli treated in the step (1) on a steaming drawer according to a circle (shown in figure 1);

(3) adding 800g of water into a steamer to boil, then placing the steamer tray in the step (2) on the steamer to steam broccoli, wherein the steaming power is 100W; and stopping cooking when the broccoli is mature.

Example 2

The steaming power in step (3) of example 1 was adjusted to 500W, and the rest was kept the same as example 1, thereby obtaining mature broccoli.

Example 3

The steaming power in step (3) of example 1 was adjusted to 1000W, and the rest was kept the same as example 1, to obtain mature broccoli.

Example 4

The steaming power in step (3) of example 1 was adjusted to 1600W, and the rest was kept the same as example 1, to obtain mature broccoli.

Example 5

The steaming power in step (3) of example 1 was adjusted to 2100W, and the rest was kept the same as example 1, to obtain mature broccoli.

The matured broccoli obtained in examples 1 to 5 were subjected to the performance test, and the test results are shown in the following table 1:

table 1 results of color change tests for examples 1-5

TABLE 2 results of the oxidation resistance test of examples 1-5

As can be seen from tables 1 and 2: when the broccoli steamed at different powers reaches the same maturity, the a value shows a descending trend along with the increase of the steaming power, namely the green intensity is increased; the contents of chlorophyll and carotenoid integrally show an increasing trend; the total phenol content of broccoli steamed at different powers is higher than that of fresh unprocessed broccoli, and the higher the steaming power is, the higher the total phenol content is (773 mg/100g dry base and 868mg/100g dry base for 100W and 1600W respectively); the content of the ascorbic acid after steaming is reduced, but more ascorbic acid content is kept compared with that of 1600W and 100W (the 100W and 1600W are 669.31mg/100g dry basis and 821.76mg/100g dry basis respectively); the oxidation resistance is closely related to the total phenol content and the ascorbic acid content, and the higher the steaming power is, the higher the ascorbic acid and total phenol content is, and the higher the oxidation resistance activity is. Therefore, the larger the steam amount is, the greener the surface color of the broccoli is, the higher the retention rate of the contents of chlorophyll, carotenoid, total phenol and ascorbic acid is, and the higher the corresponding antioxidant activity is.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.