Peeled corn kernels, peeled corn food capable of being stored at normal temperature and processing technology of peeled corn kernels

Abstract

The invention discloses peeled corn kernels, a peeled corn food capable of being stored at normal temperature and a processing technology of the peeled corn kernels. The processing technology of the peeled corn kernels comprises the following steps: peeling quick-frozen corn kernels with peels to obtain the peeled corn kernels; the center temperature of the quick-frozen corn kernels with the husks is less than or equal to-18 DEG C; the environment temperature for peeling is less than or equal to-18 DEG C; the number of times of peeling is 3-7. The processing technology of the peeled corn food capable of being stored at the normal temperature comprises the following steps: cooking raw materials of the peeled corn food capable of being stored at the normal temperature, wherein the raw materials comprise the peeled corn kernels; the sterilization coefficient F0 value of the cooking process is greater than or equal to 30. According to the processing technology of the peeled corn kernels, the husks of the corn kernels can be removed to the greatest extent, the corn kernels are easier to process and boil when being prepared into corn foods, and the prepared peeled corn foods are higher in solid content.

Description

Technical Field

[0001] The invention relates to a dehulled corn kernel, a dehulled corn food which can be stored at room temperature and a processing technology thereof. Background Art

[0002] Fresh corn is a common grain used as a side dish because it is rich in nutrients, including protein, fat, lutein and other nutrients. It has a sweet and soft taste and is often the best choice for healthy people and children. Corn porridge stored at room temperature now uses glutinous corn or sweet corn with skin. The corn porridge has distinct grains in the taste, and the corn skin will not decompose with the extension of storage time, affecting the taste. On the other hand, the cortex of corn kernels is not easy to digest.

[0003] Moreover, due to the presence of corn husk, the contents in the corn kernels are not easily released during the cooking process. Although there are some reports on the peeling process of corn kernels in the prior art, the effects of the peeling process on taste, retention of nutrients, etc. are not studied, and there are few reports on the cooking process of peeled corn kernels. There are certain technical difficulties in realizing the industrialized mass production of peeled corn kernel food. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of corn foods stored at room temperature in the prior art, that is, corn husks are left on the food, the taste is poor, or nutrients are seriously lost, and to provide a dehulled corn kernel, a dehulled corn food that can be stored at room temperature, and a processing technology thereof.

[0005] The fresh corn kernel peeling process provided by the present invention can peel fresh corn (such as white glutinous corn and yellow glutinous corn) cleanly while keeping the shape intact and the nutrient content stable.

[0006] The processing technology of the peeled corn food (such as peeled corn soup) that can be stored at room temperature provided by the present invention can produce corn food (such as peeled corn soup) with a soft and sticky taste, bright color, and high solid and soluble solid contents. It can meet the standard requirements of corn soup products on the basis of reducing the amount of corn kernels added, thereby reducing costs. In addition, after the peeled corn kernels are steamed at high temperature, the content of nutrients can be effectively guaranteed.

[0007] The present invention provides a processing technology for peeled corn kernels, which comprises the following steps:

[0008] Peeling the quick-frozen corn kernels with husks to obtain peeled corn kernels;

[0009] The central temperature of the quick-frozen corn kernels with skin is ≤-18°C;

[0010] The environmental temperature of the peeling is ≤-18°C;

[0011] The number of peeling is 3-7 times.

[0012] Since fresh corn is tender and juicy, has a high moisture content, and is not easy to peel, the present invention peels the corn kernels after quick freezing (for example, using a peeling machine to peel), thereby solving the problem that fresh corn kernels are not easy to peel, and the epidermis of corn kernels of different varieties can be completely peeled off, while retaining the shape of complete corn kernels, and the nutritional components are stable, without loss of nutritional components due to grinding and filtering. At the same time, it also solves the problem that the corn husk is difficult to digest and affects the taste of the product.

[0013] The processing technology of the dehulled corn kernels in the present invention can remove the corn kernel husks to the greatest extent, making it easier to process and cook corn food, and the prepared corn food (such as corn soup) has a higher solid content. It can be seen that the output rate of dehulled corn kernels is higher.

[0014] In some embodiments of the present invention, the quick-frozen corn kernels with husk are obtained by quick-freezing corn kernels with husk.

[0015] In some embodiments of the present invention, the quick freezing temperature is ≤-25°C.

[0016] In some embodiments of the present invention, the quick freezing time is ≥ 6 min.

[0017] In some embodiments of the present invention, the core temperature of the corn kernels after quick freezing is ≤-18°C.

[0018] In some embodiments of the present invention, the freezing rate of the quick freezing is 3.0-3.6°C / min.

[0019] In some embodiments of the present invention, the core temperature of the quick-frozen corn kernels with skin is ≤-19°C.

[0020] In the present invention, when the peeling environment temperature is greater than -18°C, continuous peeling is impossible because the machine relies on high-speed grinding to peel the skin. When the sample enters the machine, it will cause a certain temperature rise and easily become muddy, causing internal blockage and inability to discharge the material.

[0021] In some embodiments of the present invention, the peeling environment temperature is ≤-20°C.

[0022] In some embodiments of the present invention, during the peeling process, the central temperature of the quick-frozen corn kernels with skin is ≤-18°C.

[0023] In some embodiments of the present invention, the peeling is performed 5-7 times.

[0024] The invention also provides a dehulled corn kernel, which is prepared by adopting the processing technology of the dehulled corn kernel.

[0025] The present invention also provides a processing technology for a peeled corn food that can be stored at room temperature, which comprises the following steps:

[0026] The raw materials of the dehulled corn food which can be stored at room temperature are prepared by steaming, wherein:

[0027] The raw materials include the dehulled corn kernels as described above;

[0028] The sterilization coefficient F0 value of the cooking process is ≥30.

[0029] The processing technology of the dehulled corn food (such as corn soup) that can be stored at room temperature in the present invention can increase the soft, glutinous and elastic taste of the corn soup and increase the solid content of the product. Compared with the corn kernels with skin, the solid content of the dehulled corn soup is higher when the same amount of corn kernels is added.

[0030] In some embodiments of the present invention, the raw materials include, by weight: 20-50 parts of the dehulled corn kernels, 2-4 parts of sugar, and 46-78 parts of water.

[0031] In some embodiments of the present invention, the cooking temperature is ≥ 115°C.

[0032] In some embodiments of the present invention, the cooking time is ≥ 20 min.

[0033] In some embodiments of the present invention, the cooking pressure is 0.18-0.22 MPa.

[0034] In some embodiments of the present invention, the cooking temperature is ≥115° C., the cooking time is ≥20 min, and the cooking pressure is 0.18-0.22 MPa.

[0035] In some embodiments of the present invention, the sterilization coefficient F0 value of the cooking process is ≥35.

[0036] In some embodiments of the present invention, the raw materials of the dehulled corn food (such as corn soup) that can be stored at room temperature are filled into packaging materials and then steamed.

[0037] In the prior art, the corn raw material boiling process generally sterilizes the raw material first and then fills it. The present invention can adopt a process of filling the raw material first and then sterilizing it, which has high requirements for sterilization intensity and needs to ensure that the raw material and packaging material are sufficiently sterilized. The processing technology of the peeled corn food (such as corn soup) that can be stored at room temperature in the present invention does not cause loss of nutrients, and at the same time obtains a higher sterilization F0 value, which can be stored at room temperature, and also solves the cost of sterilizing the packaging material separately and the equipment configuration cost, saving production time, equipment cost, site cost, and optimizing the production process.

[0038] In some embodiments of the present invention, the mass content of soluble solids in the dehulled corn food (such as corn soup) that can be stored at room temperature is ≥6.00%.

[0039] In some embodiments of the present invention, the mass content of solids in the dehulled corn food (such as corn soup) that can be stored at room temperature is ≥60.00%.

[0040] In some embodiments of the present invention, the protein content of the dehulled corn food (such as corn soup) that can be stored at room temperature is ≥ 0.8 g / 100 g.

[0041] In some embodiments of the present invention, the fat content of the dehulled corn food (such as corn soup) that can be stored at room temperature is ≥ 0.0g / 100g.

[0042] The invention also provides a dehulled corn food that can be stored at room temperature, which is prepared by using the processing technology of the dehulled corn food that can be stored at room temperature.

[0043] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0044] The reagents and raw materials used in the present invention are commercially available.

[0045] The positive and progressive effects of the present invention are:

[0046] (1) Due to the presence of corn husk, the contents in corn kernels are not easily released during the cooking process. The present invention improves the yield of corn food (higher solid content) and enhances the unique taste of the product by quick freezing and peeling the corn kernel raw materials. The processing technology of peeled corn kernels in the present invention can completely peel the husk of corn kernels (such as white glutinous corn kernels and yellow glutinous corn kernels) while maintaining a complete shape and a stable nutrient content.

[0047] (2) Compared with the corn soup product made from unpeeled corn kernels, the corn soup product made from the peeled corn kernels of the present invention has a higher content of solids and soluble solids when the same amount of corn is added. The corn soup product can meet the standard requirements of corn soup products on the basis of reducing the amount of corn added, thereby reducing costs and improving the sensory indicators of corn food such as color and taste.

[0048] (3) The processing technology of the corn food (such as corn soup) of the present invention has a sterilization coefficient F0 value ≥ 30 and can be stored at room temperature. In addition, the processing technology of the dehulled corn food (such as corn soup) that can be stored at room temperature in the present invention can also adopt a process of heating the raw materials and the packaging material together, which has a high sterilization intensity, an F0 value of ≥ 30, a small nutritional loss, and a smooth taste. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is the appearance of the peeled glutinous corn kernels obtained by peeling three times in Example 1.

[0050] Figure 2 This is the appearance of the peeled glutinous corn kernels obtained by peeling twice in Comparative Example 4.

[0051] Figure 3 This is the appearance of the peeled glutinous corn kernels obtained by peeling 9 times in Comparative Example 5.

[0052] Figure 4 This is the appearance of the peeled corn soup that can be stored at room temperature prepared in Example 1.

[0053] Figure 5 This is the appearance of the peeled corn soup that can be stored at room temperature prepared in Comparative Example 4.

[0054] Figure 6 This is the appearance of the peeled corn soup that can be stored at room temperature prepared in Comparative Example 5.

[0055] Figure 7 This is a comparison diagram of the appearance of peeled glutinous corn kernels in Example 1 (left side) and the appearance of unpeeled quick-frozen corn kernels in Comparative Example 7 (right side).

[0056] Figure 8 This is the appearance picture of the peeled glutinous corn kernels in Example 1.

[0057] Fig. 9 This is the appearance picture of the peeled glutinous corn kernels in Example 2.

[0058] Fig.10 This is the appearance picture of the peeled glutinous corn kernels in Comparative Example 7.

[0059] Fig.11 This is a diagram showing the temperature change at the center of the corn kernel during the peeling process in step (2) of Example 1. DETAILED DESCRIPTION

[0060] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0061] In the present invention, the term "quick freezing" refers to freezing food rapidly to form extremely small ice crystals without seriously damaging cell tissues. For example, reaching a specified temperature below -18°C in the shortest possible time can quickly pass through the ice crystal formation zone, avoid puncturing cell walls, and reduce nutrient loss.

[0062] In the present invention, the term F0 value is the standard sterilization time, which is the equivalent sterilization time given to a product at 121° C. during the sterilization process. That is, the F0 value represents the sterilization intensity, and the higher the value, the safer the product is stored at room temperature and the lower the microbial risk.

[0063] In the present invention, the term soluble solids (%) refers to the general term for all substances dissolved in water in a liquid or fluid food (such as the corn food (such as corn soup) that can be stored at room temperature in the present invention), including sugar, acid, minerals and soluble fiber, etc.; the percentage refers to the mass percentage of soluble solids in the liquid or fluid food.

[0064] In the present invention, the term solids (%) refers to edible substances insoluble in water in a liquid or fluid food (such as the corn food (such as corn soup) that can be stored at room temperature in the present invention); the percentage refers to the mass percentage of the solids in the liquid or fluid food.

[0065] In the present invention, protein (g / 100g) refers to the content of protein in every 100 grams of corn food (such as corn soup) that can be stored at room temperature, that is, the percentage of the mass of protein in the total mass of the corn food that can be stored at room temperature.

[0066] In the present invention, fat (g / 100g) refers to the fat content in every 100 grams of corn food (such as corn soup) that can be stored at room temperature, that is, the percentage of the mass of fat to the total mass of the corn food that can be stored at room temperature.

[0067] In some embodiments of the present invention, the quick-frozen corn kernels with husk are obtained by quick-freezing the corn kernels with husk.

[0068] In some embodiments of the present invention, the corn kernels with husk may be conventional corn kernels in the art, such as glutinous corn kernels, yellow glutinous corn kernels, white glutinous corn kernels, white sweet and glutinous corn kernels, or yellow sweet and glutinous corn kernels.

[0069] In the present invention, the corn kernels with husk can be obtained by conventional methods in the art, for example:

[0070] After removing the corn husk and silk, the corn cobs are threshed by a corn thresher.

[0071] In some embodiments of the present invention, the corn kernels with husk are sequentially subjected to air separation to remove impurities, double-layer screening to remove impurities, washing, and single-layer screening to remove impurities before being quick-frozen.

[0072] In some embodiments of the present invention, the winnowing and impurity removal process is: using winnowing and impurity removal equipment to winnow corn kernels to remove light-density foreign matter such as corn silk and corn husks.

[0073] In some embodiments of the present invention, the double-layer screening and impurity removal process is: use a rotary impurity removal device to screen the corn kernels, pass through a 2-layer rolling screen, the inner aperture is about 1.5-2cm round hole, the outer screen is about 0.5cm wide and 1cm long elliptical aperture, large-sized foreign matter remains on the inner screen, small-sized foreign matter is discharged through the outer screen, and the middle layer is the qualified size material, and large-sized foreign matter and small-sized foreign matter, especially broken corn kernels, are removed.

[0074] In some embodiments of the present invention, the cleaning process is: use a rotary cleaning machine to clean and screen the corn kernels, first drop them into a pool, a water nozzle in the pool blows water forward, and a water pipe drains water from the bottom to the pool to form a disturbance, so as to clean the surface of the corn kernels, and foreign matter with relatively small density is discharged because it floats on the water surface.

[0075] In some embodiments of the present invention, the single-layer screening and impurity removal process is as follows: the cleaned corn kernels fall into a single-layer sieve and are rinsed by water spraying. The aperture of the sieve is divided into two sections. The small-sized sieve holes at the first end are about 0.5 cm wide and 1 cm long elliptical apertures that screen out small-sized foreign objects. The aperture size of the rear section is about 1.5-2 cm round holes. Qualified materials leak down into the water pool, and large-sized foreign objects remain in the sieve and are discharged.

[0076] In some embodiments of the present invention, the corn kernels with husk are blanched in hot water before being quick-frozen.

[0077] The temperature of the hot water blanching may be 90-100°C, for example 97°C.

[0078] The blanching time in hot water may be 1-15 min, for example 10 min.

[0079] After blanching with hot water, the corn kernels may be cooled and drained, and a vibrating spreading machine may be used to spread the drained corn kernels, and the thickness of the corn kernels may be less than 4 cm.

[0080] In the present invention, the quick freezing can be carried out in conventional quick freezing equipment.

[0081] In some embodiments of the present invention, the quick freezing may be performed in a quick freezing tunnel.

[0082] In some embodiments of the present invention, the quick freezing temperature is ≤-25°C, such as ≤-30°C, and also such as -32°C, -31°C or -32°C.

[0083] In some embodiments of the present invention, the quick freezing time is ≥6 min, such as ≥10 min, and also such as 12 min, 15 min or 13 min.

[0084] In some embodiments of the present invention, after the quick freezing is completed, the central temperature of the corn kernels with husk is ≤ -18°C, for example, -18°C, -20°C or -19°C.

[0085] In some embodiments of the present invention, the freezing temperature of the quick-frozen corn kernels with skin is ≤-18°C, such as -18°C, -20°C or -19°C.

[0086] In some embodiments of the present invention, the freezing rate of the quick freezing is 3.0-3.6°C / min, such as 3.6°C / min, 3.0°C / min or 3.4°C / min.

[0087] In some embodiments of the present invention, the core temperature of the quick-frozen corn kernels with skin is ≤-19°C, such as -20°C or -19°C.

[0088] In some embodiments of the present invention, the peeling is performed 3-7 times.

[0089] In some embodiments of the present invention, the peeling is performed 3-5 times.

[0090] In some embodiments of the present invention, the peeling is performed 5-7 times.

[0091] In some embodiments of the present invention, the peeling is performed 3 times, 5 times or 7 times.

[0092] In some embodiments of the present invention, the peeling method is high-speed grinding peeling.

[0093] In some embodiments of the present invention, the peeling process is performed by a peeling machine. The peeling machine can be a conventional peeling machine in the art, such as a peeling machine model FTPW-20 purchased from Shandong Jinyouliang Peeling and Flour Milling Equipment Co., Ltd.

[0094] In some embodiments of the present invention, the peeling power of the peeling machine is 10-20 KW, for example, 15 KW.

[0095] In some embodiments of the present invention, the peeling speed is 6-7 kg / min, that is, 6-7 kg of the quick-frozen corn kernels with skin can be processed per minute.

[0096] In the present invention, the peeled corn kernels obtained by the processing technology of the peeled corn kernels can obtain complete peeled corn kernel raw materials (such as yellow glutinous peeled corn kernel raw materials or white glutinous peeled corn kernel raw materials). By adopting the processing technology of the peeled corn kernels of the present invention, the corn skin can be completely removed, and the grains are complete without broken grains, the shape of the corn kernels is retained, and the nutritional components such as protein and fat are stable; the technical problem that the corn skin cannot be absorbed and the taste is poor can be effectively solved.

[0097] In some embodiments of the present invention, the dehulled corn kernels are screened, graded, color-sorted, and metal-detected before being steamed.

[0098] The screening and grading may be to use a grading vibrating screen to grade and collect corn kernels of different sizes.

[0099] The color sorting may be to use a color sorter to automatically sort out particles of different colors.

[0100] The metal detection can be to remove metal foreign bodies that may be introduced during the processing, such as nuts, screws, welding slag, etc., through metal detection equipment. The metal detection can reduce the risk of food safety.

[0101] In some embodiments of the present invention, the raw materials include: the blanched corn kernels, sugar, and water.

[0102] The weight proportion of the dehulled corn kernels may be 20-50 parts, such as 20 parts, 25 parts or 50 parts.

[0103] The sugar may be conventional sugar in the art, such as white granulated sugar.

[0104] The weight proportion of the sugar may be 2-4 parts, such as 2 parts, 4 parts or 2.5 parts.

[0105] The water may be conventional water in the art, such as purified water.

[0106] The weight proportion of the water may be 46-78 parts, such as 78 parts, 46 parts or 72.5 parts.

[0107] In a specific embodiment of the present invention, the raw materials include, by weight: 20 parts of the dehulled corn kernels, 2 parts of sugar, and 78 parts of water.

[0108] In a specific embodiment of the present invention, the raw materials include, by weight: 50 parts of the dehulled corn kernels, 4 parts of sugar, and 46 parts of water.

[0109] In a specific embodiment of the present invention, the raw materials include, by weight: 25 parts of the blanched corn kernels, 2.5 parts of sugar, and 7.25 parts of water.

[0110] In some embodiments of the present invention, the sugar and the water are first mixed to prepare sugar water, and then the sugar water is mixed with the blanched corn kernels.

[0111] The sugar and the water may be mixed for a conventional time in the art, such as 10-20 min, or 15 min.

[0112] In some embodiments of the present invention, the cooking temperature is ≥ 115°C, such as 119°C, 117°C or 125°C.

[0113] In some embodiments of the present invention, the cooking time is ≥ 20 min, such as 40 min, 30 min or 36 min.

[0114] In some embodiments of the present invention, the cooking pressure is 0.18-0.22 MPa, for example, 0.22 MPa, 0.18 MPa or 0.216 MPa.

[0115] In some embodiments of the present invention, the sterilization coefficient F0 value of the cooking process is ≥35, such as ≥37, ≥39 or ≥40.

[0116] In some embodiments of the present invention, the sterilization coefficient F0 value of the cooking process is 37, 39 or 40.78.

[0117] In a specific embodiment of the present invention, the cooking process is 119° C., 40 min, and 0.22 MPa.

[0118] In a specific embodiment of the present invention, the cooking process is 117° C., 30 min, and 0.18 MPa.

[0119] In a specific embodiment of the present invention, the cooking process is 125° C., 36 min, and 0.216 MPa.

[0120] In some embodiments of the present invention, the cooking method is water bath heating.

[0121] In the present invention, the filling may be conventional filling in the art.

[0122] In the present invention, the filling is generally followed by vacuum heat sealing.

[0123] In the present invention, after filling, quality inspection is generally performed before steaming. The quality inspection indexes may include whether there is water leakage, whether there is water remaining in the seal, whether the seal is uneven, whether the vacuum value is low, etc.

[0124] In some embodiments of the present invention, the box dropping time for filling is 2.0-4.0s, for example 3.0s.

[0125] In the present invention, the box dropping time of filling generally refers to the time interval from the start of filling to the end of filling.

[0126] In some embodiments of the present invention, the filling time is 1.0-2.0 s, for example 1.3 s.

[0127] In the present invention, the filling time refers to the time of the actual filling operation.

[0128] In some embodiments of the present invention, the sealing time after filling is 4.0-6.0 s, for example 5.5 s.

[0129] In some embodiments of the present invention, a cooling process is further included after the cooking.

[0130] In some embodiments of the present invention, the cooling process includes two steps of cooling, the first step of cooling is: temperature 35-45°C and time 10-30 min, and the second step of cooling is: temperature 20-30°C and time 10-20 min.

[0131] In some embodiments of the present invention, the primary cooling temperature is 35°C, 45°C or 40°C.

[0132] In some embodiments of the present invention, the time for the first cooling is 10 min, 20 min or 30 min.

[0133] In some embodiments of the present invention, the secondary cooling temperature is 20°C, 28°C or 30°C.

[0134] In some embodiments of the present invention, the secondary cooling time is 10 min, 15 min or 20 min.

[0135] In a specific embodiment of the present invention, the cooling process is: a primary cooling temperature of 35° C. and a time of 30 min, and a secondary cooling temperature of 20° C. and a time of 20 min.

[0136] In a specific embodiment of the present invention, the cooling process is: a primary cooling temperature of 45° C. and a time of 10 min, and a secondary cooling temperature of 30° C. and a time of 10 min.

[0137] In a specific embodiment of the present invention, the cooling process is: a primary cooling temperature of 40° C. and a time of 20 min, and a secondary cooling temperature of 28° C. and a time of 15 min.

[0138] In some embodiments of the present invention, the processing technology of the dehulled corn food that can be stored at room temperature is:

[0139] The dehulled corn kernels are screened, color-sorted, and metal-detected, and then sugar water is prepared;

[0140] Mixing the dehulled corn kernels and the syrup, filling and quality inspection;

[0141] The product after quality inspection is steamed and cooled to obtain the product.

[0142] In some embodiments of the present invention, the mass content of soluble solids in the dehulled corn food that can be stored at room temperature is ≥ 6.00%, for example, 6.33%, 13.70% or 8.13%.

[0143] In some embodiments of the present invention, the mass content of solids in the dehulled corn food that can be stored at room temperature is ≥ 60.00%, for example, 65.00%, 97.00% or 76.80%.

[0144] In some embodiments of the present invention, the protein content of the dehulled corn food that can be stored at room temperature is ≥ 0.8 g / 100 g, for example, 0.8 g / 100 g, 2.0 g / 100 g or 1.1 g / 100 g.

[0145] In some embodiments of the present invention, the fat content of the dehulled corn food that can be stored at room temperature is ≥ 0.0 g / 100 g, for example, 0 g / 100 g, 0.9 g / 100 g or 0.5 g / 100 g.

[0146] In some embodiments of the present invention, the color of the blanched corn food that can be stored at room temperature is white or yellow.

[0147] In some embodiments of the present invention, the dehulled corn food that can be stored at room temperature has a soft, waxy and elastic taste.

[0148] In some embodiments of the present invention, the sensory evaluation score of the blanched corn food that can be stored at room temperature is ≥20, such as 21, 25 or 27.

[0149] In the present invention, the dehulled corn food that can be stored at room temperature can be conventional dehulled corn food in the art, such as dehulled corn porridge, dehulled corn soup or dehulled corn steamed cake.

[0150] In the following embodiments and comparative examples, the sensory evaluation score table of the peeled corn soup is shown in Table 1 below.

[0151] Table 1 Sensory evaluation score sheet

[0152]

[0153] The soluble solids (%) content is determined by the refractometer method, specifically:

[0154] For undiluted samples, when the measuring temperature is below 20°C, the refractometer reading minus the correction value is the soluble solid content of the sample; when the measuring temperature is above 20°C, the refractometer reading plus the correction value is the soluble solid content of the sample.

[0155] The detection method of solid content (%) refers to QB 1007-1991 "Determination of net weight and solid content of canned food".

[0156] The detection method of protein (g / 100g) content refers to GB 5009.5-2016 "National Food Safety Standard Determination of Protein in Food".

[0157] The detection method of fat (g / 100g) content refers to GB 5009.6-2016 "National Food Safety Standard Determination of Fat in Food".

[0158] Color: Visual observation.

[0159] Taste: Taste method.

[0160] Corn kernel peeling machine, purchased from Shandong Jinyouliang Peeling and Flour Milling Equipment Co., Ltd., model FTPW-20.

[0161] Example 1: A process for processing peeled corn soup that can be stored at room temperature

[0162] This embodiment provides a peeled corn soup that can be stored at room temperature, and its ingredients are, by weight, 20 parts of peeled glutinous corn kernels, 2 parts of white sugar, and 78 parts of purified water. The specific preparation method is as follows:

[0163] (1) Production of quick-frozen corn kernels: The inspected corn is peeled with a corn husking machine to remove the corn husk and silk, and the corn cobs are threshed with a special corn thresher. The corn kernels are winnowed and impurities are removed with an air separation and impurity removal device to remove light foreign matter such as corn silk and corn husk. The corn kernels are then screened with a rotary impurity removal device through a two-layer rolling screen with an inner hole diameter of about 1.5-2cm and an outer screen with an elliptical hole diameter of about 0.5cm wide and 1cm long. Large foreign matter is retained on the inner screen, and small foreign matter is discharged through the outer screen. The middle layer is the qualified size material, and large and small foreign matter, especially broken corn kernels, are removed. A rotary cleaning machine is used to clean and screen the corn kernels. They first fall into a pool of water, where a nozzle blows water forward. A water pipe drains water from the bottom of the pool to form a disturbance, so as to clean the surface of the corn kernels. Foreign matter with relatively small density is discharged because it floats on the water surface. The cleaned corn kernels fall into a single-layer sieve and are rinsed by water spray. The aperture of the sieve is divided into two sections. The small-sized sieve holes at the first end are about 0.5cm wide and 1cm long. The elliptical aperture screens out small-sized foreign matter. The aperture size of the rear section is about 1.5-2cm. Qualified materials leak into the pool, and large-sized foreign matter remains in the sieve and is discharged. Then blanch the corn kernels in hot water at 97℃ for 10 minutes, cool and drain them after blanching, and use a vibrating spreading machine to spread the drained corn kernels. The thickness of the corn kernels is less than 4cm. They enter the quick freezing tunnel for quick freezing. The temperature of the quick freezing tunnel is -32℃ and the quick freezing time is 12 minutes. After quick freezing, the center temperature of the corn kernels is -18℃ and the freezing rate is 3.6℃ / min. They are stored for freezing at a frozen storage temperature of -18℃.

[0164] (2) Peeling of quick-frozen corn kernels: Use the quick-frozen corn kernels in step (1), and the central temperature of the quick-frozen corn kernels is -18°C. The peeling environment temperature must be controlled at -18°C, and the central temperature of the corn kernels during the peeling process is ≤ -18°C (the temperature change of the center of the corn kernels during the peeling process is as follows: Fig.11 ), start the machine (the model of the corn peeling machine is FTPW-20, purchased from Shandong Jinyouliang Peeling and Flour Making Equipment Co., Ltd.), put the quick-frozen corn kernels into the feeding port, peel 3 times (peeling power of the peeling machine: 15KW; peeling speed is 6-7kg of quick-frozen corn kernels per minute), peeled corns of different sizes are transported to the grading screen through the elevator conveyor belt, sieved, and the corn is screened and graded to obtain peeled corn kernels. The type of quick-frozen corn kernels that can be peeled in this embodiment is glutinous corn kernels, and the peeled glutinous corn kernels are obtained, and their appearance is as shown in the figure Figure 1 shown.

[0165] (3) Screening and grading: using a grading vibration screen to grade and collect the dehulled waxy corn kernels of different sizes in step (2);

[0166] (4) Color sorting: Use a color sorter to automatically sort out the different-colored particles from the peeled waxy corn kernels after screening and grading;

[0167] (5) Metal detection: Metal foreign matter that may be introduced during the processing, such as nuts, screws, welding slag, etc., can be removed from the peeled glutinous corn kernels after screening, grading and color sorting through metal detection equipment to reduce food safety risks;

[0168] (6) Dissolving sugar: Pour the white sugar and water into a mixing bucket according to the weight ratio of 20 parts of peeled glutinous corn kernels, 2 parts of white sugar, and 78 parts of purified water, and dissolve for 15 minutes to form sugar water for later use;

[0169] (7) Filling: Use automatic filling equipment to fill the product and set the filling parameters (box drop time 3.0s, filling time 1.3s, sealing time 5.5s). Put 20 portions of peeled glutinous corn kernels and 80 portions of syrup into the filling packaging material after setting the parameters. After preparation, start the equipment. The robot arm opens the packaging material and the filling pump adds materials. After adding 20 portions of peeled glutinous corn kernels and 80 portions of syrup, the peeled glutinous corn kernels and syrup enter the vacuum chamber for vacuum heat sealing.

[0170] (8) Selection: The canned samples are selected and discarded according to the conditions such as water leakage, water residue in the seal, uneven seal, and low vacuum value.

[0171] (9) High-temperature cooking: The selected products are neatly placed on a plate and pushed into the sterilizer for sterilization at 119°C, heating time 40 minutes, and heating pressure 0.22 MPa.

[0172] (10) Cooling: Cooling is carried out in two steps, the first cooling temperature is 35℃ and the time is 30 min, and the second cooling temperature is 20℃ and the time is 20 min.

[0173] (11) Storage: After sterilization, the samples are manually sorted and placed in bags according to bag bulging and other factors, and then packed and stored.

[0174] The sterilization conditions, F0 value and various parameters of the corn soup that can be stored at room temperature in this embodiment are shown in Table 2 below.

[0175] Table 2

[0176]

[0177] Example 2: A process for processing peeled corn soup that can be stored at room temperature

[0178] Compared with Example 1, this example provides a peeled corn soup that can be stored at room temperature, and its ingredients are, by weight, 50 parts of peeled glutinous corn kernels, 4 parts of white sugar, and 46 parts of purified water.

[0179] Except for the following parameters, the other steps and parameters of the specific preparation method are the same as those in Example 1.

[0180] (1) Preparation of quick-frozen corn kernels: quick-freezing tunnel temperature is -31°C, quick-freezing time is 15 min, the center temperature of the corn kernels after quick-freezing is -20°C, the freezing rate is 3.0°C / min, and the kernels are put into storage for freezing, and the frozen storage temperature is -20°C. The remaining conditions of step (1) are the same as those in Example 1.

[0181] (2) Peeling quick-frozen corn kernels: The quick-frozen corn kernels in step (1) are used, and the central temperature of the quick-frozen corn kernels is -20°C. The peeling environment temperature needs to be controlled at -20°C, and the central temperature of the corn kernels during the peeling process is ≤-18°C. The machine is started, and the quick-frozen corn kernels are put into the feeding port, and peeled for 7 times to obtain peeled glutinous corn kernels. The remaining conditions of step (2) are the same as those in Example 1.

[0182] Step (3) to step (5) are the same as in Example 1.

[0183] (6) Dissolving sugar: Pour the white sugar and water into a mixing bucket according to the weight ratio of 50 parts of peeled glutinous corn kernels, 4 parts of white sugar, and 46 parts of purified water, and dissolve for 15 minutes to form sugar water for later use;

[0184] (7) Filling: Use automatic filling equipment to fill the product, set the filling parameters (same as in Example 1), add 50 parts of peeled glutinous corn kernels and 50 parts of syrup, put in the filling packaging material after setting the parameters, and start the equipment after preparation. The robot arm opens the packaging material, and the filling pump adds materials, 50 parts of peeled glutinous corn kernels and 50 parts of syrup. After the peeled glutinous corn kernels and syrup are added, enter the vacuum chamber and vacuumize and heat seal.

[0185] Step (8) is the same as in Example 1.

[0186] (9) High-temperature steaming: The selected products are neatly placed on a plate and pushed into the sterilizer for sterilization. The heating temperature is 117°C, the heating time is 30 minutes, and the heating pressure is 0.18 MPa.

[0187] (10) Cooling: Cooling is carried out in two steps, the first cooling temperature is 45℃ and the time is 10 min, and the second cooling temperature is 30℃ and the time is 10 min.

[0188] Step (11) is the same as in Example 1.

[0189] The sterilization conditions, F0 value and various parameters of the corn soup that can be stored at room temperature in this embodiment are shown in Table 3 below.

[0190] Table 3

[0191]

[0192] Example 3: A process for processing peeled corn soup that can be stored at room temperature

[0193] Compared with Example 1, this example provides a peeled corn soup that can be stored at room temperature, and its ingredients are, by weight, 25 parts of peeled glutinous corn kernels, 2.5 parts of white sugar, and 72.5 parts of purified water.

[0194] Except for the following parameters, the other steps and parameters of the specific preparation method are the same as those in Example 1.

[0195] (1) Preparation of quick-frozen corn kernels: quick-freezing tunnel temperature is -32°C, quick-freezing time is 13 min, the center temperature of the corn kernels after quick-freezing is -19°C, the freezing rate is 3.4°C / min, and the kernels are put into storage for freezing, and the frozen storage temperature is -19°C. The remaining conditions of step (1) are the same as those in Example 1.

[0196] (2) Peeling of quick-frozen corn kernels: The quick-frozen corn kernels used have a central temperature of -19°C. The peeling environment temperature needs to be controlled at -18°C. During the peeling process, the central temperature of the corn kernels is ≤ -18°C. The machine is started, and the quick-frozen corn kernels are put into the feeding port. The peeling is performed 5 times to obtain peeled glutinous corn kernels. The remaining conditions of step (2) are the same as those in Example 1.

[0197] Step (3) to step (5) are the same as in Example 1.

[0198] (6) Dissolving sugar: Pour the white sugar and water into a mixing bucket according to the weight ratio of 25 parts of peeled glutinous corn kernels, 2.5 parts of white sugar, and 72.5 parts of purified water, and dissolve for 15 minutes to form sugar water for later use;

[0199] (7) Filling: Use automatic filling equipment to fill the product, set the filling parameters (same as in Example 1), 25 parts of peeled glutinous corn kernels, 75 parts of syrup, after setting the parameters, put in the filling packaging material, and start the equipment after preparation. The robot arm opens the packaging material, and the filling pump adds the material, 25 parts of peeled glutinous corn kernels, 75 parts of syrup, and after the peeled glutinous corn kernels and syrup are added, enter the vacuum chamber and vacuumize and heat seal.

[0200] Step (8) is the same as in Example 1.

[0201] (9) High-temperature steaming: The selected products are neatly placed on a plate and pushed into the sterilizer for sterilization. The heating temperature is 125°C, the heating time is 36 minutes, and the heating pressure is 0.216 MPa.

[0202] Cooling: Cooling is divided into two steps, the first cooling temperature is 40℃ and the time is 20min, and the second cooling temperature is 28℃ and the time is 15min.

[0203] Step (11) is the same as in Example 1.

[0204] The sterilization conditions, F0 value and various parameters of the corn soup that can be stored at room temperature in this embodiment are shown in Table 4 below.

[0205] Table 4

[0206]

[0207] According to Examples 1-3, it can be seen that:

[0208] By quick-freezing and peeling the corn kernels, the product yield (solid content) is increased and the unique taste of the product is enhanced, overcoming the technical difficulty of the corn kernels’ contents being difficult to release during the cooking process due to the presence of the corn husk. Specifically:

[0209] The fresh corn kernels are quick-frozen to remove the husk of the fresh corn kernels. The parameters for removing the husk of the fresh corn kernels are determined to remove the husk of the white glutinous corn or the yellow glutinous corn cleanly and keep the shape intact with stable nutrient content.

[0210] The actual effect of dehulling is determined through the final corn soup product parameters. When the same amount of corn is added, the solid and soluble solid contents detected are higher when dehulled corn kernels are used as raw materials (for example, when the amount of dehulled corn kernels added is 20%, the soluble solid content reaches 6.33%). The standard requirements of corn soup products can be met on the basis of reducing the amount of corn kernels added, thus reducing costs.

[0211] In addition, the nutrient content of peeled glutinous corn kernels can be effectively guaranteed after high-temperature steaming.

[0212] Comparative Example 1

[0213] Compared with Example 1, this comparative example uses the room temperature corn kernels after being drained in step (1), without the quick freezing in step (1), and directly performs the peeling treatment in step (2).

[0214] In this comparative example, since the corn kernels have more juice and soft texture, after entering the peeling machine, the corn will be ground into mud, which will block the grinding space and the material will not come out.

[0215] Comparative Example 2

[0216] Compared with Example 1, in step (1) of this comparative example, corn kernels with a central temperature of -8°C are used. The steps for preparing the quick-frozen corn kernels in step (1) are as follows:

[0217] Put the glutinous corn kernels into the quick freezing tunnel with the tunnel temperature <-30℃ and the quick freezing time of 4 minutes. After the quick freezing, the center temperature of the corn kernels is about -8℃. Put the quick-frozen corn kernels into the freezer and adjust the storage temperature to -8℃ to -10℃.

[0218] After quick freezing, refer to Example 1 and perform the quick frozen corn kernel peeling process in step (2).

[0219] In this comparative example, since the corn kernels have more juice and soft texture, after entering the peeling machine, the corn will be ground into mud, which will block the grinding space and the material will not come out.

[0220] Comparative Example 3

[0221] Compared with Example 1, the peeling environment temperature in step (2) of this comparative example is -9°C, and the other parameters are the same as those in Example 1.

[0222] When the quick-frozen corn kernels are peeled in this comparative example, the friction heat generated inside the machine is very high when the quick-frozen corn kernels are ground. Therefore, when the corn kernels and the ambient temperature are not reached, they will melt and become muddy after entering the machine, and the machine will be blocked and unable to discharge. Continuous production is impossible in industry.

[0223] Comparative Example 4

[0224] Compared with Example 1, the number of peeling times in step (2) of this comparative example is 2, and the other parameters are the same as those in Example 1.

[0225] Comparative Example 5

[0226] Compared with Example 1, the number of peeling times in step (2) of this comparative example is 9, and the other parameters are the same as those in Example 1.

[0227] Observe the pictures of peeling 2 and 9 times in Comparative Example 4 and Comparative Example 5, as shown in FIG. Figure 2 (Peeling 2 times), Figure 3 As shown in (peeling 9 times), most of the epidermis remains on the upper part and both sides of the corn after peeling twice. Peeling more than 3 times and less than 7 times can complete the grinding and achieve the desired effect. Therefore, peeling 9 times will not only increase the workload of the factory, but the more times the corn is ground, the more fragments the grains will become, resulting in nutrient loss.

[0228] Table 5 is a comparison table of the peeled waxy corn kernels obtained in Example 1, Comparative Example 4, and Comparative Example 5.

[0229] Table 5

[0230]

[0231] Table 6 is a comparison table of the corn soups that can be stored at room temperature prepared in Example 1, Comparative Example 4, and Comparative Example 5.

[0232] Table 6

[0233]

[0234] Note: The soluble solids, solids, protein (g / 100g), fat (g / 100g), color, product pictures, taste, and sensory evaluation in Table 6 are all for the final product: corn soup that can be stored at room temperature;

[0235] The fat content in Table 6 is less than 0.5 g / 100g and is labeled as 0 (refer to GB 28050-2011 "National Food Safety Standard - General Rules for Nutrition Labeling of Pre-packaged Foods").

[0236] Comparative Example 6: A process for processing peeled corn soup that can be stored at room temperature

[0237] Compared with Example 2, the high-temperature cooking in step (9) of this comparative example is as follows: the selected products are neatly placed on a plate and pushed into a sterilizer for sterilization at a heating temperature of 105°C, a heating time of 40 min, and a heating pressure of 0.15 MPa.

[0238] Step (10): Cooling: One-step cooling, natural cooling for 50 minutes.

[0239] The remaining parameters are the same as those in Example 2.

[0240] The sterilization conditions, F0 value and various parameters of the corn soup that can be stored at room temperature in this comparative example are shown in Table 7 below.

[0241] Table 7

[0242]

[0243] The F0 value represents the sterilization intensity. The higher the value, the safer the product is stored at room temperature and the lower the microbial risk. By comparison, the F0 value in Comparative Example 6 is lower than that in Example 2. It can be seen that low-temperature cooking has an impact on the values ​​of soluble solids and solids. Under the same initial raw material addition amount, the higher the values ​​of soluble solids and solids in the corn soup that can be stored at room temperature in Example 2, the higher the intensity of raw material cooking and the higher the raw material yield (the higher the solid content).

[0244] Comparative Example 7

[0245] Compared with Example 3, this comparative example omits step (2) and uses unpeeled quick-frozen corn kernels. The appearance of the peeled glutinous corn kernels in Example 1 ( Figure 7 Left side) and the appearance of unpeeled quick-frozen corn kernels in Comparative Example 7 ( Figure 7 Right side) comparison chart Figure 7 shown.

[0246] The remaining parameters are the same as those in Example 3.

[0247] The sterilization conditions, F0 value and various parameters of the corn soup that can be stored at room temperature in this comparative example are shown in Table 8 below.

[0248] Table 8

[0249]

[0250] It can be seen from Comparative Example 7 and Example 3 that:

[0251] The peeling process affects the soluble solids content of corn kernels. When the initial raw material addition amount is the same, the soluble solids content in the corn soup that can be stored at room temperature in Example 3 is higher, and the corn soup has a better taste and a higher sensory score.

[0252] Table 9 is a comparison table of peeled glutinous corn kernels obtained by different peeling times in Example 1, Example 2 and Comparative Example 7.

[0253] Table 9

[0254]

[0255] It can be seen from Examples 1-2 and Comparative Example 7 that:

[0256] Peeling the corn kernels more than 3 times and less than 7 times can not only remove the skin of the corn kernels, but also maintain the complete shape of the corn kernels and ensure the nutritional content.

Claims

1. A process for processing peeled corn kernels, characterized in that: It includes the following steps: Peeling the quick-frozen corn kernels with husks to obtain peeled corn kernels; The central temperature of the quick-frozen corn kernels with skin is ≤-18°C; The environmental temperature of the peeling is ≤-18°C; The number of peeling is 3-7 times.

2. The process for processing dehulled corn kernels according to claim 1, characterized in that: The quick-frozen corn kernels with husk are obtained by quick-freezing the corn kernels with husk; The quick freezing temperature is ≤-25°C; The quick freezing time is ≥ 6 min; The freezing rate of the quick freezing is 3.0-3.6°C / min.

3. The processing technology of dehulled corn kernels as claimed in claim 1 or 2, characterized in that: The central temperature of the quick-frozen corn kernels with skin is ≤-19°C; The environmental temperature of the peeling is ≤-20°C; During the peeling process, the central temperature of the quick-frozen corn kernels with skin is ≤-18°C; The number of peeling is 5-7 times.

4. A dehulled corn kernel, characterized in that: The corn kernels are prepared by the processing technology of dehulled corn kernels as described in any one of claims 1 to 3.

5. A processing technology for peeled corn food that can be stored at room temperature, characterized in that: It includes the following steps: The raw materials of the dehulled corn food which can be stored at room temperature are prepared by steaming, wherein: The raw material includes the dehulled corn kernels as claimed in claim 4; The sterilization coefficient F0 value of the cooking process is ≥30.

6. The processing technology of the peeled corn food that can be stored at room temperature as claimed in claim 5, characterized in that: Calculated by weight, the raw materials include: 20-50 parts of the dehulled corn kernels, 2-4 parts of sugar, and 46-78 parts of water.

7. The processing technology of the dehulled corn food that can be stored at room temperature as claimed in claim 5 or 6, characterized in that: The cooking temperature is ≥115°C; the cooking time is ≥20min; the cooking pressure is 0.18-0.22MPa; And / or, the sterilization coefficient F0 value of the cooking process is ≥35.

8. The processing technology of the dehulled corn food that can be stored at room temperature as claimed in any one of claims 5 to 7, characterized in that: The raw materials of the dehulled corn food that can be stored at room temperature are filled into packaging materials and then steamed.

9. The processing technology of the dehulled corn food that can be stored at room temperature as claimed in any one of claims 5 to 8, characterized in that: In the dehulled corn food that can be stored at room temperature: The mass content of soluble solids is ≥ 6.00%; The mass content of solids is ≥ 60.00%; Protein content ≥ 0.8g / 100g; Fat content ≥0.0g / 100g.

10. A dehulled corn food that can be stored at room temperature, characterized in that: The dehulled corn food is prepared by the processing technology of the dehulled corn food that can be stored at room temperature as described in any one of claims 5 to 9.

Images