阅读说明：本技术 一种低温速溶琼脂糖的制备方法 (A kind of preparation method of low-temperature instant agarose ) 是由 罗凯文 徐卓越 谢小玲 于 2019-08-30 设计创作，主要内容包括：本发明涉及琼脂生产技术领域,具体涉及一种低温速溶琼脂糖的制备方法,所述制备方法包括将普通琼脂粉在有机溶剂的保护下,使用复合有机酸进行糖苷键的水解,使小分子琼脂果胶溶解在溶液中,过滤,取滤渣用碱水解,再使用碳酸二甲酯进行甲酯化、过离子交换树脂。本发明具有制备简单、纯度高、带电荷少、低温溶解性好的优点。(The present invention relates to agar production technical fields; more particularly to a kind of preparation method of low-temperature instant agarose; the preparation method include by plain agar powder under the protection of organic solvent; the hydrolysis of glycosidic bond is carried out using composite organic acid; make small molecule agar pectolysis in the solution; filtering, takes filter residue basic hydrolysis, reuses dimethyl carbonate and carries out esterification, crosses ion exchange resin.The present invention have the advantages that preparation simple, purity is high, it is electrically charged less, dissolution in low temperature it is good.)

1. a kind of preparation method of low-temperature instant agarose, which comprises the steps of:

(1) raw material organic solvent is handled: organic solvent and water is added in plain agar powder, obtains mixed solution；

(2) acidolysis: mixed solution and organic acid are mixed, and filtering obtains filter residue 1；

(3) basic hydrolysis: by filter residue 1 plus water, add alkali, obtain solution 2；

(4) esterification: being added dimethyl carbonate in solution 2, obtains solution 3；

(5) cross ion exchange resin: by solution 3 by ion exchange resin, it is dry to get.

2. preparation method according to claim 1, which is characterized in that organic solvent described in step (1) is ethyl alcohol, isopropyl At least one of alcohol, n-butanol, isobutanol, the tert-butyl alcohol, ethyl acetate, toluene, acetone；Organic acid described in step (2) is At least one of acetic acid, propionic acid, tartaric acid, citric acid, sulfamic acid, oxalic acid, lactic acid, amion acetic acid, stearic acid；Step (3) alkali described in is sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, carbonic acid At least one of hydrogen potassium.

3. preparation method according to claim 2, which is characterized in that organic acid described in step (2) is sulfamic acid, lemon The Compound-acid of lemon acid and oxalic acid；Alkali described in step (3) is the compound alkali of sodium hydroxide, calcium hydroxide and sodium carbonate.

4. preparation method according to claim 3, which is characterized in that the quality of the sulfamic acid, citric acid and oxalic acid Than for 1:2-4:3-5；The mass ratio of the sodium hydroxide, calcium hydroxide and sodium carbonate is 0.5-2:1:1-4.

5. preparation method according to claim 1, which is characterized in that plain agar powder described in step (1) and organic molten The mass volume ratio of agent is 1:40-80g/mL；The mass volume ratio of the plain agar powder and water is 1:10-20g/mL；Step (2) mass volume ratio of organic acid described in and mixed solution is 0.0001-0.001:1g/mL；Filter residue 1 described in step (3) Mass volume ratio with water is 1:20-40g/mL；The mass volume ratio of the alkali and water is 0.0001-0.001:1g/mL；Step (4) volume ratio of solution 2 described in and dimethyl carbonate is 6-12:1.

6. preparation method according to claim 1, which is characterized in that the step (2) includes the following steps: to mix molten Liquid and organic acid mix at 70-100 DEG C, time 60-120min, ultrasonic wave added acidolysis, ultrasonic power 800-1500w, filters pressing, Pressure 0.1-1.0MPa obtains filter residue 1.

7. preparation method according to claim 1, which is characterized in that the step (3) includes the following steps: filter residue 1 Add water, add alkali, be heated to 90-100 DEG C, time 60-120min obtains solution 2；The step (4) includes the following steps: in solution Dimethyl carbonate is added in 2,80-100 DEG C of temperature, time 60-120min obtains solution 3.

8. preparation method according to claim 1, which is characterized in that ion exchange resin described in step (5) be sun from At least one of sub-exchange resin, anion exchange resin.

9. preparation method according to claim 1, which is characterized in that the step (5) includes the following steps: solution 3 It is cooled to 60-70 DEG C, neutralization pH is 6.0-8.0, crosses cation exchange resin, and temperature is down to 45-55 DEG C, crosses anion exchange tree Rouge, it is dry to get.

10. the low-temperature instant agarose that any one of the claim 1-9 preparation method is prepared is in food, daily chemical product Application.

Technical field

The present invention relates to agar production technical fields, and in particular to a kind of preparation method of low-temperature instant agarose.

Background technique

Agar, scientific name agar-agar also known as agar, agar, agar-agar, delicacy made from bird's nests essence, agel-agal, cold day, big dish slice, are the one of natural plant gum Kind, it is the hy-drophilic polysaccharide class colloid extracted from the marine red algas such as agar, fragrant plant mentioned in ancient texts dish, seaweed, main component is The sulfuric acid ester of poly galactolipin is current one of widest seaweed glue of purposes in the world, because agar is in thickening property, stabilization Property, conformality, gelation, film forming etc. there is significant superiority, can be used as thickener, coagulator, suspending agent, Emulsifier, antistaling agent and stabilizer.Even if the concentration of agar remains to form quite stable gel down to 1%.In field of food, Agar is the food additives of generally acknowledged safety, furthermore in many aspects such as medical industry, daily-use chemical industry, bioengineering, agar Also there is extensive and far-reaching application.

Agar is made of agarose (agarose) and agar pectin (agaropectin).Agarose is linear more Polymers, agar pectin are by the heterogeneous mixture of many smaller molecular compositions.Their structure is similar, but agar pectin band sulphur Acid group and carboxyl group, gelling ability are poor.

Agarose is linear polymer, and basic structure is in the β-D- galactolipin of 1,3 connections and 3,6- of Isosorbide-5-Nitrae connection The long-chain that ether-L- galactolipin alternately connects, agarose containing sulfate radicals are fewer than agar, have special gelling property, especially have Significant stability and hysteresis quality, and easily absorb moisture, there is special stabilizing effect, have been widely used for biology, food, The fields such as medicine, chemical industry, weaving, national defence.Agarose is generally heated to 90 DEG C or more in water and dissolves, and temperature drops to 35-40 DEG C when form the gel of good semi-solid, this is the main feature and basis that it serves many purposes.

The gelation of agarose is caused by existing hydrogen bond, and all factors that can destroy hydrogen bond lead to gelation It destroys.Agarose has hydrophily, and charged group is almost not present, and seldom causes to become to sensitive large biological molecule Property and absorption, are ideal inert carriers.It needs agar pectin to remove as far as possible in agarose preparation process, otherwise agarose It there may be denier sulfate radical and pyruvic acid replace ionizing group, cause electroendosmosis (EEO), movement of the electroendosmosis to particle It has an impact.The preferable agarose sulfate radical content of quality is relatively low, usually 0.2% hereinafter, electroendosmosis is smaller, usually exists 0.13 or less.

The production technology of plain agar are as follows:

1, pre-process: seaweed raw material is rinsed in washing, to remove asparagus, silt particle and other sundries in fragrant plant mentioned in ancient texts, as far as possible The interference of despumation.

2, alkali process: pretreated asparagus is placed in NaOH solution, and lye dosage is generally to cover asparagus Algae is preferred, with preference temperature heated at constant temperature certain time.

3, it cleans: the good asparagus of alkali process sufficiently being washed with water, after cleaning up, is washed till pH between 7-8.

4, bleach: the pH of NaClO solution is adjusted to about 9 with hydrochloric acid by the NaClO solution of certain volume, certain effective chlorine, The asparagus for being washed till neutral is placed in bleaching liquid, bleaching liquid is usually to cover asparagus to be preferred, certain time is bleached, in order to Bleaching uniformly, when asparagus is put into bleaching liquid, be stirred rapidly sufficiently, be then allowed to stand to the stipulated time.

5, it is acidified: the asparagus after bleaching is placed in certain density HCl solution, HCl solution dosage is generally with covering Firmly asparagus algae is preferred, acidification 5min or so；In order to be acidified uniformly, when asparagus is put into hydrochloric acid solution, to stir rapidly and fill Point, it is then allowed to stand to the stipulated time.

6, it cleans: the asparagus after acidification sufficiently being washed with water, is washed till pH 7.5 or so.

7, it mentions glue: mentioning glue about 50min in boiling water having rinsed to neutral asparagus frond, water consumption is asparagus weight 20 times, and observe plastic emitting feelings and wish, after having mentioned glue, filter while hot, natural cooling solidification.

8, lyophilization: room temperature agar after cooling being freezed, agar fully charge is made, dehydration of then thawing.

9, dry and crushing: agar is dried, is crushed.

Main production plain agar powder domestic at present, processing technology is cumbersome, and big using soda acid amount, water consumption is big, but institute The economic benefit of generation is lower；Occupied by overseas enterprise, foreign countries, which develop, to be had for the processing technology of opposite high added value The agar of different physical properties or different chemical property has low-freezing system for example, external agar sugar product just has numerous series Column, dissolution in low temperature series, high-melting-point series, high-resolution series, high intensity etc., and external agarose price is domestic common 20 times to 200 times of agar powder price differ, so be badly in need of proposing a kind of preparation method of low-temperature instant agarose.

106957375 A of Chinese patent application CN discloses a kind of production technology for refining low-temperature instant agarose, packet Include following steps: 1, low-temperature instant agar is improved under traditional agar production technology using plain agar as raw material, will Agar carries out purification purification；2,95% alcohol treatment；3, alkali process；4, it cleans；5, it is acidified；6, it cleans: will be after acidification with water Agar sufficiently washs, and is washed till pH 7.0 or so；7, glue is mentioned；8, centrifugation removal of impurities；9, granulating and drying；10, microwave disinfection；11, at Product.The agarose appearance color that the patent is prepared is shallow compared with plain agar, and impurity is few, as clear as crystal after dissolution, lower At a temperature of also can quickly dissolve.Most agar can be dissolved in 45 DEG C, 5min.But step is more complex, need into Row is cleaned multiple times, and soda acid processing carries out in aqueous solution, is unfavorable for the separation of agarose and agaropectin, the purity of agarose has Wait further increase.

103936890 A of Chinese patent CN discloses a kind of preparation method of low setting temperature agarose, including following step Rapid: agarose and deionized water press (w/v) 20:1~30:1 Hybrid Heating colloidal sol；NaBH is added after colloidal sol₄, it is 80 DEG C in temperature Lower reaction 15min；0.5M NaOH activated agarose hydroxyl is added, dressing agent dimethyl suflfate is then added；It uses after reaction Salt acid for adjusting pH is to neutrality, then uses ethanol precipitation.Dimethyl suflfate is used in the patent, is more toxic, safety is lower, simultaneously The purity of agarose also needs to be further increased.

Therefore, a kind of preparation method for the low-temperature instant agarose that can solve above-mentioned technical problem of exploitation is very must It wants.

Summary of the invention

There is provided the purpose of the present invention is overcome the deficiencies in the prior art it is a kind of prepare it is simple, with high purity, electrically charged less, it is low The preparation method of the good low-temperature instant agarose of warm dissolubility.

The present invention is achieved by the following technical programs:

A kind of preparation method of low-temperature instant agarose, includes the following steps:

(1) raw material organic solvent is handled: organic solvent and water is added in plain agar powder, obtains mixed solution；

(2) acidolysis: mixed solution and organic acid are mixed, and filtering obtains filter residue 1；

(3) basic hydrolysis: by filter residue 1 plus water, add alkali, obtain solution 2；

(4) esterification: being added dimethyl carbonate in solution 2, obtains solution 3；

(5) cross ion exchange resin: by solution 3 by ion exchange resin, it is dry to get.

Water used in the present invention uses reverse osmosis membrane filtration technical treatment, without pure water, pure water is referred both under specified otherwise Ask conductivity less than 5 μ s/cm.

Plain agar powder described in step (1) is to extract to obtain from marine red alga, such as agar, fragrant plant mentioned in ancient texts dish or purple Dish.

Preferably, organic solvent described in step (1) is ethyl alcohol, isopropanol, n-butanol, isobutanol, the tert-butyl alcohol, acetic acid second At least one of ester, toluene, acetone.The agaropectin of small-molecular-weight is dissolved in certain polar organic solvent, and agarose is then not It is dissolved in organic solvent.

It is highly preferred that organic solvent described in step (1) is ethyl alcohol, in isopropanol, n-butanol, ethyl acetate, acetone It is at least one.

Preferably, the mass volume ratio of plain agar powder described in step (1) and the organic solvent is 1:40-80g/ mL。

Preferably, the mass volume ratio of plain agar powder described in step (1) and water is 1:10-20g/mL.

It is highly preferred that the step (1) includes the following steps:

(1) raw material organic solvent handle: by plain agar powder respectively according to mass volume ratio be 1:40-80g/mL and 1: Organic solvent and water is added in 10-20g/mL, obtains mixed solution.

Preferably, organic acid described in step (2) is acetic acid, propionic acid, tartaric acid, citric acid, lactic acid, oxalic acid, amino sulphur At least one of acid, amion acetic acid, stearic acid.

It is highly preferred that organic acid described in step (2) is at least one of citric acid, sulfamic acid, oxalic acid.

It is highly preferred that organic acid described in step (2) is the Compound-acid of sulfamic acid, citric acid and oxalic acid.

It is highly preferred that the mass ratio of the sulfamic acid, citric acid and oxalic acid is 1:2-4:3-5.

Preferably, the mass volume ratio of organic acid described in step (2) and mixed solution is 0.0001-0.001:1g/mL.

It is highly preferred that step (2) includes the following steps:

Organic acid and mixed solution are mixed at 70-100 DEG C according to mass volume ratio for 0.0001-0.001:1g/mL, Time 60-120min, ultrasonic wave added acidolysis, ultrasonic power 800-1500w, filters pressing, pressure 0.1-1.0MPa obtain filter residue 1.

Hydrolysis of glycoside bond in agar can mainly be hydrolyzed 1,3 glycosidic bonds and Isosorbide-5-Nitrae glycosidic bond by organic acid, so that Agar molecular weight becomes smaller.The agaropectin of small-molecular-weight is dissolved in certain polar organic solvent, and agarose does not dissolve in then organic molten Agent, while pyruvic acid group is also more likely to be hydrolyzed and remove in acid, by filters pressing, can preferably remove agaropectin, The purity of agarose is improved, sulphates content is reduced.Especially when the Compound-acid that organic acid is sulfamic acid, citric acid and oxalic acid When, glycosidic bond and pyruvic acid group in agar can hydrolyze under the acidic environment of low concentration, and energy consumption is lower, and The degree of hydrolysis of agar is higher.

Preferably, alkali described in step (3) is sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium carbonate, carbon At least one of sour potassium, sodium bicarbonate, saleratus.

It is highly preferred that alkali described in step (3) is at least one of sodium hydroxide, calcium hydroxide and sodium carbonate.

It is highly preferred that alkali described in step (3) is the compound alkali of sodium hydroxide, calcium hydroxide and sodium carbonate.

It is highly preferred that the mass ratio of the sodium hydroxide, calcium hydroxide and sodium carbonate is 0.5-2:1:1-4.

Preferably, the mass volume ratio of filter residue 1 described in step (3) and water is 1:20-40g/mL.

Preferably, the mass volume ratio of alkali described in step (3) and water is 0.0001-0.001:1g/mL.

It is highly preferred that step (3) includes the following steps:

Basic hydrolysis: filter residue 1 is added into water according to mass volume ratio 1:20-40g/mL, the mass volume ratio according to alkali and water is 0.0001-0.001:1g/mL adds alkali, is heated to 90-100 DEG C, and time 60-120min obtains solution 2.

The main component of filter residue 1 is agarose, and side chain has a small amount of sulfate and galacturonic acid, and there are also a small amount of agar fruits Glue, filter residue 1 dissolve by heating in water, and agar is made to be untwisted by double-spiral structure, become disordered state, and alkali is added and is hydrolyzed, fine jade The groups such as acetyl group, methoxyl group, the sulfate of rouge glue side chain are more likely to slough under the alkaline condition, and sulfate group Hydrolysis is changed into 3,6- inner ether-L- galactolipin, to eliminate the charged groups such as sulfate.3,6- inner ether-L- galactolipin is fine jade One important indicator of rouge, the gel strength that content increases agar also will increase.

Preferably, the volume ratio of solution 2 described in step (4) and dimethyl carbonate is 6-12:1.

It is highly preferred that step (4) includes the following steps:

Dimethyl carbonate is added according to volume ratio 6-12:1 in solution 2,80-100 DEG C of temperature, time 60-120min is obtained Solution 3.

After step (3) basic hydrolysis, agar while sloughing the strong ionic groups such as sulfate, can also slough methoxyl group, The groups such as ethyoxyl, acetyl group simultaneously form electrically charged carboxyl, and under alkaline condition, dimethyl carbonate obtains step (3) Solution 2 carries out esterification, is esterified in agar the carboxyl that generates after the galacturonic acid of script and hydrolysis, can play neutralization carboxylic The effect of acid, while reducing charge.And dimethyl carbonate is compared with other dimethyl esters, such as dimethyl suflfate, and toxicity is lower, It is safer, and non-toxic product is classified as by Europe.

Show galacturonic acid esterification and methylation using dimethyl carbonate and agar by experiment, introduces first Oxygroup, methyl, the methyl being introduced into that methylates replace the hydrogen of hydroxyl in agar to form methoxyl group.The first that agarose is introduced, generated Oxygroup is different from naturally occurring methoxyl group in agar, and solution temperature and freezing point do not rise anti-drop.It may be the double spiral shells of agarose The supination of structure solution is revolved, derivative methoxyl group is produced due to its site, and when agarose being made to form double-spiral structure again Raw " steric hindrance ", but do not destroy its main chain, still keeps its gel characteristic, while when agarose dissolves again is required Heat greatly reduces.

Preferably, ion exchange resin described in step (5) be cation exchange resin, in anion exchange resin extremely Few one kind.

It is highly preferred that solution 3 is first passed through cation exchange resin in the step (5), then pass through anion exchange tree Rouge.

It is highly preferred that the anion exchange resin is strong-basicity styrene series anion exchange resin, macroporous strong basic Styrene series anion exchange resin, macroreticular weakly base acrylic acid type anion exchange resin and macroreticular weakly base polystyrene yin At least one of ion exchange resin.

It is highly preferred that the cation exchange resin is sulfonic group polystyrene gel-type strong-acid cation exchange tree Rouge, sulfonic group polystyrene macroporous type storng-acid cation exchange resin, carboxylic acid group's macropore acidulous acrylic acid's cation At least one of exchanger resin.

It is highly preferred that the step (5) includes the following steps: for solution 3 to be cooled to 60-70 DEG C, neutralization pH is 6.0- 8.0, cross cation exchange resin, temperature is down to 45-55 DEG C, crosses anion exchange resin, it is dry to get.

It is highly preferred that the drying mode is spray drying.

It is highly preferred that after the drying mode passes sequentially through cation exchange resin and anion exchange resin for solution 3, Be cooled to 30-35 DEG C, filters pressing obtains filter residue, filter residue is dried in vacuo, 60-105 DEG C of temperature, pressure 5-20KPa, crush to get.

Solution 3 is first passed through cation exchange resin by the present invention, then can successively remove band by anion exchange resin The cation of charge and the anionic group of hydrolysis make the charge of agar keep neutral, to reach the requirement of agarose.

The invention further relates to low-temperature instant agarose the answering in food, daily chemical product that above-mentioned preparation method is prepared With.

The beneficial effects of the present invention are:

(1) organic solvent is added in acid hemolysis process, obtained agarose purity is higher.Organic acid can be by agar main chain Hydrolysis of glycoside bond, so that agar molecular weight becomes smaller.The agaropectin of small-molecular-weight is dissolved in the organic solvent containing a small amount of water, agarose Then insoluble in organic solvent, by filters pressing, agaropectin can be preferably removed, sulphates content is reduced, improves agarose Purity.If it is in the solution system of only water heating carry out acidolysis, agaropectin and agarose or be all dissolved in water, Huo Zhedou It is not soluble in water, it cannot achieve good separation, be unfavorable for improving the purity of agarose, while sulphates content greatly improves.This Invention carries out acidolysis in organic solvent system, and the agaropectin of only small-molecular-weight is dissolved in organic solvent, realizes agaropectin With the good separation of agarose, the purity of agarose is improved.Especially when organic acid is answering for sulfamic acid, citric acid and oxalic acid Close acid when, the glycosidic bond and pyruvic acid group of agar pectin under the acidic environment of low concentration can fast hydrolyzing, energy consumption compared with It is low, and agaropectin is hydrolyzed to the maximum extent, and be dissolved in low-concentration organic solvent to greatest extent.

(2) acidolysis of the present invention is preceding, and basic hydrolysis by the sequencing both limited, is not needed in acidolysis and alkali rear Addition water-washing step is neutralized after hydrolysis, directly provides alkaline condition after basic hydrolysis for esterification, step is simpler.And When using compound alkali of the invention, it can be hydrolyzed with a small amount of alkali.

(3) present invention is added to esterification step, and for dimethyl carbonate compared with other dimethyl esters, toxicity is lower, Er Qiejia Esterification is modified agarose, reduces freezing point.After step (3) basic hydrolysis, agar is to slough sulfate etc. strong ionic While group, it can also slough the groups such as methoxyl group and form electrically charged carboxyl, under alkaline condition, dimethyl carbonate is to step (3) solution 2 that obtains carries out esterification, is esterified the carboxyl generated after the galacturonic acid of script in agar and hydrolysis, can be with Play the role of neutralizing carboxylic acid, while reducing charge.

(4) by the present invention in that with cation exchange resin and anion exchange resin, can remove electrically charged sun from Son and the anionic group of hydrolysis make the charge of agar keep neutral, meanwhile, it is suitable by the use for limiting ion exchange column Sequence, avoids the hydroxyl for first passing through anion exchange resin generation and cation is generated and precipitated, contaminated ion column, to reach The requirement of agarose.

Detailed description of the invention

Fig. 1 is the FT-IR figure of embodiment 4 and commercially available agarose.Wherein, a is 4 agarose of embodiment, and b is commercially available agar Sugar.

Fig. 2 is the influence diagram of 4 low-temperature instant agarose of embodiment and different proportion card wave to cosmetics series viscosity.

Specific embodiment

The invention will now be further described with reference to specific embodiments, the advantages and features of the present invention will be with description and It is apparent.But examples are merely exemplary for these, and it is not intended to limit the scope of the present invention in any way.Those skilled in the art Member it should be understood that without departing from the spirit and scope of the invention can details to technical solution of the present invention and form into Row modifications or substitutions, but these modifications and replacement are fallen within the protection scope of the present invention.