阅读说明：本技术 一种在烘烤过程中保持麦片纤维完整性的方法 (Method for maintaining integrity of oatmeal fibers during baking process ) 是由 姚婧 王汝佳 陈海桂 徐雪 吕佳慧 汪烁硕 于 2020-11-25 设计创作，主要内容包括：本发明涉及食品加工领域,尤其涉及一种在烘烤过程中保持麦片纤维完整性的方法,包括以下步骤：配制前处理液,并将晒干的燕麦浸泡在前处理液中一定时间后,再向其中加入脱乙酰甲壳质继续浸泡一定时间后,过滤并用去离子水洗涤后沥干,最后将经过浸渍处理后的燕麦进行烘烤,得到烘烤燕麦片。本发明克服了现有技术中的燕麦在烘烤过程中其中的膳食纤维会发生断裂的缺陷,通过在燕麦烘烤前经过前处理液浸渍,使得燕麦纤维中的氢键能够被破坏,并通过其余原料与氢键断裂处进行结合,防止了氢键的二次形成,使得纤维素的韧性大大提升,从而在高温的烘烤下能够承受更大的应力而不会断裂,在烘烤过程中有效保持了保持麦片纤维完整性。(The invention relates to the field of food processing, in particular to a method for maintaining the integrity of oatmeal fibers in a baking process, which comprises the following steps: preparing a pretreatment liquid, soaking dried oats in the pretreatment liquid for a certain time, adding deacetylated chitin, continuously soaking for a certain time, filtering, washing with deionized water, draining, and baking the soaked oats to obtain baked oatmeal. The invention overcomes the defect that dietary fiber in oat in the baking process can be broken in the prior art, hydrogen bonds in oat fiber can be destroyed by dipping the oat in the pretreatment liquid before baking, and secondary formation of the hydrogen bonds is prevented by combining other raw materials with the broken parts of the hydrogen bonds, so that the toughness of cellulose is greatly improved, the oat fiber can bear larger stress without breaking under high-temperature baking, and the integrity of the oat fiber is effectively maintained in the baking process.)

1. A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 10-15 parts of sodium acetate, 1-5 parts of disodium hydrogen phosphate, 1-5 parts of sodium citrate, 10-30 parts of glycerol, 1-3 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking the dried oat in the pretreatment solution for a certain time, adding deacetylated chitin, continuously soaking for a certain time, filtering, washing with deionized water, and draining;

(3) baking: and (3) carrying out sectional stepped heating baking on the soaked oat groats to obtain baked oatmeal with complete fibers.

2. The method of claim 1, wherein the oat flour of step (2) is added in an amount of 20-40% by weight of the pretreatment liquid.

3. The method for maintaining the fiber integrity of the oatmeal during the baking process as claimed in claim 1 or 2, wherein the temperature of the pretreatment liquid is always kept between 70-80 ℃ and the time of the first soaking is between 30-120 min.

4. The method of claim 3, wherein the chitosan is added in an amount of 1-5% by weight of the oat flour.

5. A method of preserving fiber integrity of oatmeal during baking as claimed in claim 1 or 2 or 4 wherein the time for said 2 nd soak is between 10 and 45 min.

6. A method of preserving fiber integrity during baking as claimed in claim 5 wherein sonication is used in the 2 nd soaking after the addition of deacetylated chitin.

7. The method of claim 6, wherein the ultrasonic frequency is 25 to 35 KHz.

8. The method of claim 1, wherein step (3) is preceded by freeze drying prior to baking.

9. A method for preserving fiber integrity of oatmeal during toasting as claimed in claim 1 or 8 wherein the step-wise ramp-up toasting sequence in step (3) is as follows:

and (3) low-temperature baking: baking for 30-45 min at 90-95 ℃;

baking at medium temperature: baking for 30-60 min at 110-125 ℃;

and (3) high-temperature baking: baking at 150-180 ℃ for 10-20 min.

Technical Field

The invention relates to the field of food processing, in particular to a method for maintaining the integrity of oatmeal fibers in a baking process.

Background

Dietary fiber is a polysaccharide that is neither digested nor absorbed by the gastrointestinal tract, nor produces energy. Therefore, once considered a "nutrient-free" has not been adequately appreciated for long periods of time.

However, with the intensive development of nutrition and related sciences, dietary fiber has been increasingly found to have a considerable physiological role. So that dietary fiber is more interesting to academia and common people today as the diet becomes more refined, and is recognized as a seventh group of nutrients by the nutrition community, in parallel with the traditional six groups of nutrients-protein, fat, carbohydrate, vitamin, mineral and water.

Oats are gramineous herbaceous plants, have a long planting history in China, and have a cultivation history for three thousand years. The dietary cellulose which is the main component has special physiological function in human body, can absorb a large amount of substances harmful to human body, promotes the reproduction of beneficial flora in intestinal tract and the normal peristalsis of the intestinal tract, and prevents the canceration of the intestinal tract. In addition, the health-care food also has the functions of preventing the human body from absorbing cholesterol and reducing cholesterol, is an indispensable raw material of health-care food for reducing blood sugar, blood fat, relaxing bowels, losing weight and the like, and can be widely applied to the food industry. However, oats have been subject to breakage of the otherwise intact dietary fiber during processing (e.g., baking and puffing), resulting in the breakdown of the otherwise long chain fibers into several smaller segments. Although the difference between the long-chain molecules and the short-chain molecules does not influence the absorption of other beneficial ingredients in the oat, the short-chain dietary fibers are easily taken away by gastrointestinal movement, so that the retention time in the stomach is reduced, the satiety time of eaters after eating is shorter, and more oat can be eaten, so that the human body is fattened more easily, and the health is not facilitated.

Disclosure of Invention

The invention aims to overcome the defect that dietary fiber of oat is broken in the baking process in the prior art, so the invention provides a method for maintaining the integrity of oat fiber in the baking process.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 10-15 parts of sodium acetate, 1-5 parts of disodium hydrogen phosphate, 1-5 parts of sodium citrate, 10-30 parts of glycerol, 1-3 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking the dried oat in the pretreatment solution for a certain time, adding deacetylated chitin, continuously soaking for a certain time, filtering, washing with deionized water, and draining;

(3) baking: and (3) carrying out sectional stepped heating baking on the soaked oat groats to obtain baked oatmeal with complete fibers.

The dietary fiber is one of cellulose, is macromolecular polysaccharide consisting of glucose, and has a rigid structure due to hydrogen bonds in molecules and among molecules, so that the toughness of the dietary fiber is poor. Oat is baked at a high temperature in the baking process, and the oat is also subjected to certain internal stress due to factors such as expansion in the baking process, so that the oat is easy to break at a high temperature, and the original long-chain cellulose is decomposed into a plurality of short chain links. The principle of the method is that the pretreatment liquid contains sodium acetate, disodium hydrogen phosphate, sodium citrate and other components, and after the components are dissolved in water, the pretreatment liquid has certain alkalinity and can destroy hydrogen bonds among cellulose molecules and in the cellulose molecules, and at the moment, micromolecular glycerol and xanthan gum can be combined with hydrogen bond fracture positions in the cellulose, so that the hydrogen bonds cannot be formed again in the cellulose molecules, the flexibility of the cellulose molecules is increased, and the cellulose molecules have better toughness, and can bear larger stress without fracture under high-temperature baking.

Although sodium acetate, disodium hydrogen phosphate and sodium citrate can be added to food as food additives, the oat needs to be washed after soaking for the reasons of food safety, oat flavor maintenance and the like, and glycerin and xanthan gum in the ingredients have insufficient binding force with cellulose and are easily dissolved in the washing process, so that hydrogen bonds in the cellulose are formed again. Therefore, the invention also adds micromolecular deacetylated chitin into the pretreatment liquid in the latter half of the impregnation process, and the micromolecular deacetylated chitin has good attraction effect with cellulose, so that after the deacetylated chitin is added, the surface of the cellulose can be stably coated with a layer of deacetylated chitin, and the formation of hydrogen bonds among and in the cellulose molecules can be prevented. Even after washing, deacetylated chitin prevents the formation of hydrogen bonds in cellulose.

In addition, because the molecular weight of the chitosan is higher than that of glycerol and the bonding strength with cellulose is higher, the chitosan cannot enter cellulose molecules and intermolecular interiors if being added when hydrogen bonds are not completely broken, so that the chitosan can only form a protective layer on the cellulose surface when being adsorbed to the cellulose surface, and sodium acetate, disodium hydrogen phosphate and sodium citrate are prevented from breaking the hydrogen bonds in the cellulose. Therefore, the chitosan of the present invention should be added after the dipping treatment for a certain period of time until the hydrogen bonds are completely broken, so that the toughness of the treated cellulose can be maximized.

In addition, the oat baking process adopts the step-by-step heating baking process, and the stress of the oat during the baking process can be slowly released, so that the concentrated release of the stress is prevented, and the damage to cellulose is reduced.

Preferably, in the step (2), the addition amount of the oat is 20-40% of the mass of the pretreatment liquid.

Preferably, the temperature of the pretreatment liquid is kept between 70 and 80 ℃ all the time, and the time for the first soaking is between 30 and 120 min.

According to the invention, the oat is soaked at the temperature of 70-80 ℃, so that hydrogen bonds in cellulose can be quickly destroyed, and the oat can not be gelatinized at high temperature to influence the final taste.

Preferably, the amount of the chitosan added is 1 to 5% by mass of the oat.

Preferably, the 2 nd soaking process after the deacetylation chitin is added is assisted by ultrasonic treatment.

After ultrasonic treatment, deacetylated chitin can be combined with fibers more quickly, and the modification efficiency is improved.

Preferably, the ultrasonic frequency is 25-35 KHz.

Preferably, step (3) is first freeze-dried prior to baking.

After freeze-drying, originally, moisture in the oat can be sublimated to leave holes, and air in the holes can expand in the baking process, so that the freeze-dried oat is more crisp.

Preferably, the step-by-step heating baking procedure in step (3) is as follows:

and (3) low-temperature baking: baking for 30-45 min at 90-95 ℃;

baking at medium temperature: baking for 30-60 min at 110-125 ℃;

and (3) high-temperature baking: baking at 150-180 ℃ for 10-20 min.

Therefore, the invention has the following beneficial effects:

according to the invention, the oat is soaked in the pretreatment liquid before baking, so that hydrogen bonds in oat fibers can be destroyed, and the rest raw materials are combined with the hydrogen bond fracture part, so that secondary formation of the hydrogen bonds is prevented, the toughness of cellulose is greatly improved, and the oat fiber can bear larger stress without fracture under high-temperature baking, and the integrity of the oat fiber is effectively maintained in the baking process.

Detailed Description

The invention is further described with reference to specific examples. Those skilled in the art will be able to implement the invention based on these teachings. Moreover, the embodiments of the present invention described in the following description are generally only some embodiments of the present invention, and not all embodiments. Therefore, all other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort shall fall within the protection scope of the present invention.

Example 1

A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 10 parts of sodium acetate, 1 part of disodium hydrogen phosphate, 1 part of sodium citrate, 10 parts of glycerol, 1 part of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking dried oat 20% of pretreatment liquid in pretreatment liquid at 70 deg.C for 30min, adding deacetylated chitin 1% of oat under ultrasonic condition with frequency of 25KHz, soaking for 10min, filtering, washing with deionized water, and draining;

(3) baking: carrying out sectional stepped heating baking on the oat after the soaking treatment,

the step heating baking procedure comprises the following steps:

and (3) low-temperature baking: baking at 90 deg.C for 30 min;

baking at medium temperature: baking at 110 deg.C for 30 min;

and (3) high-temperature baking: baking at 150 deg.C for 10min, and air cooling to obtain baked oatmeal with intact fiber.

Example 2

A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 15 parts of sodium acetate, 5 parts of disodium hydrogen phosphate, 5 parts of sodium citrate, 30 parts of glycerol, 3 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking dried oat 40% of pretreatment liquid in 80 deg.C pretreatment liquid for 120min, adding deacetylated chitin 5% of oat under 35KHz ultrasonic condition, soaking for 45min, filtering, washing with deionized water, and draining;

(3) baking: carrying out sectional stepped heating baking on the oat after the soaking treatment,

the step heating baking procedure comprises the following steps:

and (3) low-temperature baking: baking at 95 deg.C for 45 min;

baking at medium temperature: baking at 125 deg.C for 60 min;

and (3) high-temperature baking: baking at 180 deg.C for 20min, and air cooling to obtain baked oatmeal with intact fiber.

Example 3

A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 12 parts of sodium acetate, 3 parts of disodium hydrogen phosphate, 3 parts of sodium citrate, 20 parts of glycerol, 2 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking dried oat in pretreatment solution at 75 deg.C for 60min according to 30% of the pretreatment solution, adding deacetylated chitin 2% of the oat under 30KHz ultrasonic condition, soaking for 30min, filtering, washing with deionized water, and draining;

(3) baking: carrying out sectional stepped heating baking on the soaked oat

The step heating baking procedure comprises the following steps:

and (3) low-temperature baking: baking at 92 deg.C for 35 min;

baking at medium temperature: baking at 120 deg.C for 35 min;

and (3) high-temperature baking: baking at 160 deg.C for 15min, and air cooling to obtain baked oatmeal with intact fiber.

Example 4

A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 12 parts of sodium acetate, 2 parts of disodium hydrogen phosphate, 4 parts of sodium citrate, 15 parts of glycerol, 1.5 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking dried oat in pretreatment solution at 75 deg.C for 40min according to 25% of the pretreatment solution, adding deacetylated chitin 1.5% of the oat under ultrasonic condition of 25KHz, soaking for 40min, filtering, washing with deionized water, and draining;

(3) baking: carrying out sectional stepped heating baking on the oat after the soaking treatment,

the step heating baking procedure comprises the following steps:

and (3) low-temperature baking: baking at 90 deg.C for 35 min;

baking at medium temperature: baking at 115 deg.C for 45 min;

and (3) high-temperature baking: baking at 160 deg.C for 15min, and air cooling to obtain baked oatmeal with intact fiber.

Example 5

A method of maintaining the integrity of oat fiber during baking comprising the steps of:

(1) preparing a pretreatment liquid: preparing 14 parts of sodium acetate, 4 parts of disodium hydrogen phosphate, 2 parts of sodium citrate, 25 parts of glycerol, 2.5 parts of xanthan gum and 1000 parts of water into a solution;

(2) dipping treatment: soaking dried oat 35% of pretreatment liquid in pretreatment liquid at 78 deg.C for 100min, adding deacetylated chitin 4.5% of oat under 35KHz ultrasonic condition, soaking for 20min, filtering, washing with deionized water, and draining;

(3) baking: carrying out sectional stepped heating baking on the oat after the soaking treatment,

the step heating baking procedure comprises the following steps:

and (3) low-temperature baking: baking at 95 deg.C for 40 min;

baking at medium temperature: baking at 120 deg.C for 45 min;

and (3) high-temperature baking: baking at 175 deg.C for 12min, and air cooling to obtain baked oatmeal with intact fiber.

Comparative example 1

Comparative example 1 the same as the conventional oat baking process, i.e. baking directly at 150 ℃ for 30min, resulted in baked oatmeal.

Comparative example 2

The baking process of comparative example 2 is substantially the same as that of comparative example 1, except that the baking process of comparative example 2 adopts step-by-step temperature rise baking, and the step-by-step temperature rise baking procedure is as follows:

and (3) low-temperature baking: baking at 95 deg.C for 40 min;

baking at medium temperature: baking at 120 deg.C for 45 min;

and (3) high-temperature baking: baking at 175 deg.C for 12min, and air cooling to obtain baked oatmeal.

The baked oatmeal and the unbaked oat obtained in examples 1 to 5 and comparative documents 1 to 2 were extracted according to GB/T5009.88-200 "determination of dietary fiber in food", and the average length of the fiber was measured, and the data thereof were as follows:

TABLE 1 comparison of average length of dietary fiber in oats of the examples

Item	Length of fiber
		Example 1	~3.55mm
Example 2	~3.48mm
		Example 3	~3.60mm
Example 4	~3.58mm
		Example 5	~3.65mm
Comparative example 1	~1.56mm
		Comparative example 2	~1.92mm
Unbaked oats	~3.76mm

From the above, it can be seen that the average fiber lengths of the baked oatmeal prepared in examples 1-5 are closer to those of the unbaked oats, and compared with comparative examples 1 and 2, the integrity of the fiber in the baked oats can be effectively ensured by the method, so that satiety can be prolonged after eating, and a person eating the oat can be prevented from eating more oats in a short time, thereby being beneficial to health.