CN102987183B - Starch-pectin composite and preparation method thereof - Google Patents

Abstract

A starch-pectin compound in the field of food technology and a preparation method thereof, the method for preparing the compound is: adding starch to pectin in a ratio of 1:0.4 to 1:0.8 in mass ratio to an aqueous solution, fully Stir, mix evenly, place the mixture in a boiling water bath, stir to fully gelatinize the starch; add sodium trimetaphosphate, adjust the pH value to 10-11 with sodium hydroxide, and react at 80°C-90°C for 1-2 hours Use hydrochloric acid to adjust the pH value to 6-7, add 8-10 times the volume of ethanol, let stand overnight, collect the precipitate, dialyze, and freeze-dry to obtain the starch-pectin complex. The preparation method of the invention has low raw materials and simple process, and the content of the resistant starch in the product is more than 62%.

Description

A kind of starch-pectin compound and preparation method thereof

technical field

The invention relates to a compound in the field of food technology and a preparation method thereof, in particular to a starch-pectin compound and a preparation method thereof.

Background technique

As the main component of human staple food, starch can provide carbohydrates among the seven nutrients required by human daily. Therefore, it can be said that human health is closely related to daily starch intake. As a kind of starch, resistant starch has important physiological functions: lower blood sugar, prevent and treat diabetes; lower serum cholesterol, prevent and treat cardiovascular diseases; prevent constipation and intestinal cancer, prevent hemorrhoids; prevent stones; Beneficial microbial reproduction; promote the absorption of micronutrients such as minerals; inhibit obesity, control weight, etc. In addition, resistant starch has a low water holding capacity and a better taste than dietary fiber. It does not affect the flavor of the food when used in processed foods. On the contrary, it can improve the texture, that is, it has better appearance, texture and taste than traditional fiber, and can improve The expansion and brittleness of some foods have been widely used in food processing.

Pectin has good emulsifying, thickening, stabilizing and gelling effects, and is widely used in food, textile, printing and dyeing, tobacco, metallurgy, cosmetic production and water treatment and other fields. In the field of food, pectin is an important soluble dietary fiber, which has the functions of antibacterial, hemostasis, detumescence, detoxification, lowering blood fat, and anti-radiation.

As a food additive, sodium trimetaphosphate is often used in the preparation of cross-linked phosphate starch. Sodium trimetaphosphate is used as a reactant to cross-link pectin and starch with good functions to prepare starch-pectin complex with high nutritional value. This preparation method will be able to significantly increase the content of resistant starch in the compound, so that the compound has the dual advantages of resistant starch and pectin.

After searching the literature of the prior art, there is no report related to the method of the present invention.

Contents of the invention

The purpose of the present invention is to integrate the dual advantages of resistant starch and pectin, and provide a starch-pectin compound and a preparation method thereof. The preparation method of the present invention has low raw materials, simple process, few side reactions, few residues of by-products, high product quality, and the content of resistant starch in the product is above 62%; the starch-pectin compound prepared by the present invention can be used as a A functional food additive.

The preparation method of the starch-pectin complex involved in the present invention, comprises the steps:

a. Add starch to the aqueous solution at a ratio of 1:0.4 to 1:0.8 by mass to pectin, so that the mass fraction of the aqueous solution of the mixture of starch and pectin is 5% to 6%, then fully stir and mix After uniformity, place the mixture in a boiling water bath and stir to fully gelatinize the starch;

b. Add sodium trimetaphosphate so that the mass ratio of sodium trimetaphosphate to the mixture of starch and pectin is 1:4 to 1:6, then adjust the pH value to 10 to 11 with sodium hydroxide. ℃ reaction for 1 to 2 hours;

c. Adjust the pH value to 6-7 with hydrochloric acid, add 8-10 times the volume of ethanol, let stand overnight, collect the precipitate, dialyze with a dialysis bag with a molecular cut-off of 12,000 for 24-48 hours, and freeze-dry.

The invention uses starch, pectin and phosphate as raw materials, combines physical modification and chemical modification, and rapidly prepares high-quality starch-pectin compound through simple heating reaction under controllable humidity.

The invention has the following beneficial effects: raw materials are cheap, the process is simple, side reactions are few, residues of by-products are few, and product quality is high; the content of resistant starch in the product of the invention is more than 62%; the starch-fruit prepared by the invention As a functional food additive, the gum compound can be used in food-related fields including bread, biscuits, muffins, and pastries. It has the characteristics of improving food texture, increasing nutritional value, and increasing the added value of products. It is suitable for use in Develop new functional foods.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Fig. 2 is a thermogravimetric curve diagram of the starch-pectin complex.

Detailed ways

The following examples will further illustrate the invention.

Example 1

Referring to the process flow diagram in Fig. 1, the starch-pectin gelatinized liquid is firstly prepared through a gelatinization reaction, and then a food-grade starch-pectin compound is obtained through a cross-linking reaction.

Mix 36g of starch and 14g of pectin, add 1000ml of distilled water, stir well at room temperature, mix evenly, then place the mixture in a boiling water bath at 100°C and stir to fully gelatinize the starch to obtain a starch-pectin gelatinized liquid.

Add 12.5 g of sodium trimetaphosphate, adjust the pH value to 10 with sodium hydroxide, and react at 80° C. for 2 hours.

Adjust the pH value to 6 with hydrochloric acid, add 8000ml of ethanol, stand overnight, dialyze with a dialysis bag with a molecular cut-off of 12000 for 24 hours, and freeze-dry to obtain the starch-pectin complex. This complex can be used as a functional food additive in food-related fields including bread, biscuits, muffins, and pastries.

The obtained product was identified by thermogravimetric analyzer. Figure 2 is a thermogravimetric analysis diagram of the starch-pectin complex. It can be seen from the figure that the thermal decomposition of the starch-pectin complex is carried out in three stages. The first stage is mainly the pyrolysis of residual water molecules. The composite starts to lose weight slowly from 63°C, and has 11% weight loss at 109°C; the second stage is the thermal decomposition process of the main skeleton of the composite, which starts to decompose rapidly from 271°C , there is 38% weight loss at 290°C, and the decomposition is the fastest at 283°C; the third stage begins at 306°C, the main structure of the composite has basically been thermally decomposed, and the decomposition rate becomes slow again, and the residual mass at 700°C is 33%.

Example 2

Mix 34g of starch and 21g of pectin, add 1000ml of distilled water, stir well at room temperature, mix evenly, then place the mixture in a boiling water bath at 100°C, stir to fully gelatinize the starch, and obtain a starch-pectin gelatinized liquid.

Add 11 g of sodium trimetaphosphate, adjust the pH value to 10.5 with sodium hydroxide, and react at 85° C. for 1.5 hours.

Adjust the pH value to 6.5 with hydrochloric acid, add 9000ml of ethanol, stand overnight, dialyze with a dialysis bag with a molecular cut-off of 12000 for 36 hours, and freeze-dry to obtain the starch-pectin complex. As a functional food additive, this starch-pectin complex can be used in food-related fields including bread, biscuits, muffins, and pastries.

Example 3

Mix 33g of starch and 27g of pectin, add 1000ml of distilled water, stir well at room temperature, mix evenly, then place the mixture in a boiling water bath at 100°C, stir to fully gelatinize the starch, and obtain a starch-pectin gelatinized liquid.

Add 10 g of sodium trimetaphosphate, adjust the pH value to 11 with sodium hydroxide, and react at 90° C. for 1 hour.

Adjust the pH value to 7 with hydrochloric acid, add 10,000ml of ethanol, let stand overnight, dialyze with a dialysis bag with a molecular cut-off of 12,000 for 48 hours, and freeze-dry to obtain a starch-pectin complex. As a functional food additive, this starch-pectin complex can be used in food-related fields including bread, biscuits, muffins, and pastries.

Claims (1)

1. a preparation method for Starch-pectin composite, is characterized in that the method has following process and step:

A, joins in the aqueous solution by starch in the ratio that the mass ratio with pectin is 1:0.4 ~ 1:0.8, to make the mass fraction of the aqueous solution of starch and pectin mixture for 5% ~ 6%, then fully stir, after mixing, mixture is placed in boiling water bath, stirs, make the abundant gelatinization of starch;

B, added sodium trimetaphosphate, to make the mass ratio of sodium trimetaphosphate and starch and pectin mixture for 1:4 ~ 1:6, is then 10 ~ 11 by NaOH adjust ph, 80 DEG C ~ 90 DEG C reactions 1 ~ 2 hour;

C is 6 ~ 7 with salt acid for adjusting pH value, adds 8 ~ 10 times of volume ethanol, left undisturbed overnight, collecting precipitation, dialyses 24 ~ 48 hours with the bag filter that molecule interception is 12000, freeze drying.