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CN-122004393-A - Preparation method of oat cereal powder for improving brewing performance and reducing GI (food and beverage)

CN122004393ACN 122004393 ACN122004393 ACN 122004393ACN-122004393-A

Abstract

The application belongs to the technical field of deep processing of grains, and discloses a preparation method of oat cereal powder for improving the brewing property and reducing the GI, which comprises the steps of firstly dispersing cured oat flour according to a feed-liquid ratio of 1:4, adjusting the pH value to 4.8, adding mixed enzyme with total enzyme activity of 2.5-7.5U/g at 50deg.C for enzymolysis for 6 hr, centrifuging, washing, and drying to obtain enzymolysis oat flour, mixing enzymolysis oat flour with citric acid solution, balancing at room temperature, drying, heating, washing, and drying to obtain modified oat flour. The fourier infrared spectrum of oat flour treated by the method of the application shows a remarkable ester bond characteristic peak at 1744cm ‑1 , which proves that citric acid and starch are successfully esterified and crosslinked. The modified oat flour has the advantages of remarkably improved water retention, effectively improved hydration and dispersibility during brewing, remarkably reduced brewing caking rate, improved quick solubility and brewing quality, and remarkably reduced estimated glycemic index, which is shown by in vitro digestion simulation experiments, and has digestion slowing characteristics.

Inventors

  • LIU JIANHUA
  • JIN HAORAN
  • HE JIANFEI
  • TANG WEI

Assignees

  • 浙江工业大学

Dates

Publication Date
20260512
Application Date
20260326

Claims (9)

  1. 1. A preparation method of oat cereal powder for improving the brewing property and reducing the GI is characterized by comprising the following steps, (1) Dispersing cured oat flour in pure water according to a feed liquid ratio of 1:4, regulating pH to 4.8, magnetically stirring in a 50 ℃ water bath for 10min, adding mixed enzyme with total enzyme activity of 2.5-7.5U/g, performing enzymolysis for 6h at 50 ℃ and 150rpm, adding absolute ethyl alcohol with an enzymolysis liquid volume of 12.5% after the enzymolysis is finished, stopping the reaction, centrifuging the enzymolysis liquid, collecting precipitate, washing, drying and crushing to obtain enzymatic oat flour, 2 mixing the enzymatic oat flour with citric acid solution with a concentration of 0.01-0.05 g/mL, magnetically stirring, spreading the mixed solution in a tray, balancing for 6h at room temperature, drying overnight at 40 ℃, crushing the dried product, heating for 5h at 130 ℃, washing the product with pure water, collecting the precipitate, drying and crushing to obtain the final modified oat flour.
  2. 2. The method of claim 1, wherein the mixed enzyme in step (1) is a complex enzyme of alpha-amylase and glucanase, and the enzyme activity ratio of alpha-amylase to glucanase is 1:3.
  3. 3. The method of claim 1, wherein in step (1), the total enzyme activity of the enzyme mixture is 2.5-7.5U/g.
  4. 4. The method of claim 1, wherein in step (2), the citric acid solution is at a concentration of 0.01-0.05g/mL.
  5. 5. The method for preparing oat cereal flour of claim 1, wherein the centrifugation conditions are centrifugation at 5000rpm for 15min, the washing is 3 times with pure water, the drying is at 40 ℃ for 12h, and the comminution is by sieving through a 100 mesh sieve.
  6. 6. The method for preparing oat cereal flour with improved brewing and reduced GI according to claim 1, wherein in step (2), the pH of the citric acid solution is adjusted to 3.5, the ratio of the enzymatic oat flour to citric acid solution is 50g to 100ml, and the mixing time is 5min.
  7. 7. An oat cereal flour prepared by the method of any one of claims 1-6, characterized in that the fourier infrared spectrum has a characteristic peak at 1744cm -1 attributed to an ester bond formed by esterification cross-linking reaction of citric acid with oat starch molecules.
  8. 8. Oat cereal flour according to claim 7, characterized in that it has a water retention of more than 150%, a overrun of less than 25% and a glycemic index, EGI, lower than the standard calculated with reference to white steamed bread.
  9. 9. Use of the oat cereal flour of claim 7 in the preparation of meal replacement foods, medical use formulas, foods dedicated to diabetic people.

Description

Preparation method of oat cereal powder for improving brewing performance and reducing GI (food and beverage) Technical Field The application relates to the technical field of deep processing of grains, in particular to a preparation method of oat grain powder for improving the brewing property and reducing the GI. Background Oat (avenasativa) is rich in proteins, dietary fibers, bioactive polyphenols and flavonoids and is known as a "whole nutritional cereal". With the rise of the health consumption demands, whole grain meal replacement powders represented by oats are popular for their convenience. However, the technical bottleneck restricts the further development of the industry, on one hand, oat flour is easy to agglomerate during brewing, and the sensory experience is seriously affected, and on the other hand, the traditional processing results in higher glycemic index GI, and the traditional processing does not accord with the health trend of slow digestion and low burden. In addition, oat has the challenges of poor processing suitability and too fast digestion in beverages and reconstituted cereal products. Therefore, developing the preparation method of oat cereal powder with high brewing performance and GI reduction has important value for widening the application scene of oat and promoting industrial upgrading. Disclosure of Invention Aiming at the technical defects that the existing brewing oat flour is easy to agglomerate, has higher glycemic index GI value, limited application range and the like in the brewing process, the invention provides a processing method of enzymolysis-synergistic citric acid modified oat flour, which obviously improves the brewing dispersibility and digestion characteristics of the oat flour. The invention is based on biological enzymolysis and citric acid modification technology, improves the hydration capability of oat starch particles through specific enzyme treatment, ensures that water can be more uniformly distributed in the starch particles, promotes oat flour to be uniformly and fully swelled, effectively reduces caking phenomenon, and utilizes citric acid to induce starch molecule crosslinking and rearrangement, increases resistant starch content and reduces enzyme accessibility, thereby effectively reducing the GI value of the product. The method is simple and convenient to operate, stable in modification effect, good in brewing performance and low in digestion rate, is suitable for special people such as meal replacement, diabetes mellitus and the like, and has obvious industrial production advantages and wide market application prospects. The above object of the present invention is achieved by the following technical solutions: in one aspect, a method for preparing oat cereal flour with improved brewing and reduced GI is provided, comprising the steps of, (1) Dispersing cured oat flour in pure water according to a feed liquid ratio of 1:4, regulating pH to 4.8, magnetically stirring in a 50 ℃ water bath for 10min, adding mixed enzyme with total enzyme activity of 2.5-7.5U/g, performing enzymolysis for 6h at 50 ℃ and 150rpm, adding absolute ethyl alcohol with an enzymolysis liquid volume of 12.5% after the enzymolysis is finished, stopping the reaction, centrifuging the enzymolysis liquid, collecting precipitate, washing, drying and crushing to obtain enzymatic oat flour, 2 mixing the enzymatic oat flour with citric acid solution with a concentration of 0.01-0.05g/mL, magnetically stirring, spreading the mixed solution in a tray, balancing for 6h at room temperature, drying overnight at 40 ℃, crushing the dried product, heating for 5h at 130 ℃, washing the product with pure water, collecting the precipitate, drying and crushing to obtain the final modified oat flour. Further, the mixed enzyme in the step (1) is a complex enzyme of alpha-amylase and glucanase, and the enzyme activity ratio of the alpha-amylase to the glucanase is 1:3. Further, in the step (1), the total enzyme activity of the mixed enzyme is 2.5-7.5U/g. Further, in the step (2), the concentration of the citric acid solution is 0.01-0.05g/mL. Further, the centrifugation condition is centrifugation at 5000rpm for 15min, the washing is washing with pure water 3 times, the drying is drying at 40 ℃ for 12h, and the crushing is sieving with 100 mesh sieve. Further, in the step (2), the pH of the citric acid solution is adjusted to 3.5, the dosage ratio of the enzymatic oat flour to the citric acid solution is 50g to 100mL, and the mixing and stirring time is 5min. On the other hand, an oat cereal flour prepared by the preparation method is provided, wherein the Fourier infrared spectrum of the oat cereal flour has a characteristic peak at 1744cm -1, and the characteristic peak is attributed to an ester bond, and the ester bond is formed by esterification crosslinking reaction of citric acid and oat starch molecules. Further, the water retention is more than 150%, the brewing caking rate is less tha