CN101040712A - Compound containing DAG and the method for preparing the same - Google Patents

Abstract

The invention provides a method for preparing a compound with diacylglyceride, via enzyme catalysis. The inventive compound comprises aliphatic acid glyceride as main component, wherein the diacylglyceride comprises 20-50% diacylglyceride, 20-40% oleic acid acyl-linolic acid acyl glycerin, 15-40% 2-oleic acid acyl glycerin, 3-10% linolenic acid acyl-linolic acid acyl glycerin, and 0-3% 2-glyceryl palmitate. And the content of diacylglyceride of inventive product is higher than 94%, with high unsaturated degree of fatty acid, lower than 3% of 2-santuraed acyl glycerin, and lower than 5% 3-acyl glycerin, while the compound is clear and transparent at normal temperature or lower temperature. And the invention uses 1-acyl glycerin as material with low cost, wide resource and low producing lost.

Description

The composition and method of making the same that contains DG

Technical field

The present invention relates to a kind of composition that contains DG, especially have the product of higher DG content, high degree of unsaturation; The invention still further relates to the preparation method of said composition.

Background technology

Except be applied to fields such as food, medicine, feed and cosmetics as important additive, DG receives increasing concern because of its remarkable physiologically active at field of food.With the traditional plant oil phase ratio that is rich in triacylglycerol, DG can also prevent obesity, reduce blood fat effectively for human body provides heat, essential fatty acid, liposoluble vitamin etc. on the basis that guarantees the grease mouthfeel.This mainly be because triacylglycerol and DG absorbs in human body and the difference of metabolism due to: triacylglycerol is hydrolysis generation β-an acylglycerol in small intestine, and the DG hydrolysis generates α (or α ')-an acylglycerol, the latter is low by the efficient that metabolism enters tissue, has limited the accumulation of fat at tissue; And DG oxidation as quick as thought in vivo can improve the energy i (in vivo) balance, prevents obesity and other bad illness.So, be exactly the raising of DG content in the composition and the reduction of triacylglycerol content to one of major criterion of the quality improvement of DG product.

Another important parameter of decision DG product quality is into the degree of unsaturation of the fatty acid residue of ester, and saturated fatty acid content is high more, and degree of unsaturation is low more.This parameter determines the physicochemical property and the nutritional quality of DG product to a great extent.The saturated fatty acid that distributes in the DG product, especially long carbochain saturated fatty acid (14～22 carbon) content is high more, and the freezing point/fusing point of product is also high more.When the content of two saturated glyceride in the DG product greater than 3% the time, product at normal temperatures or be solid or semisolid in the human body temperature scope uses very inconvenience, the absorptivity in human body or animal body also reduces greatly.In addition, the absorption of saturated fatty acid also can increase the danger of diseases such as suffering from high fat of blood, artery sclerosis.

The production of DG mainly contains chemical method and biological enzyme.The reaction condition gentleness of enzymatic synthesis of diacyl glycerine; product special flavour is good; the efficiency of pcr product height; the product purity height is saved the energy, meets environmental requirement; can satisfy industrial requirement again; these all are traditional incomparable advantages of chemical method, so enzyme catalysis method is widely applied to (grain and food industry, 2006 the 6th phases the 13rd volume: 12～14 pages) in the industrial production of DG.

Glycerine solution or esterification synthetic method are the methods of the enzymatic synthesis of diacyl glycerine used always:

The former can be under certain water content, and lipase-catalyzed grease glycerine is separated, and after reaction a period of time, reduces reaction temperature, DG is separated out, the efficiency of pcr product height.But product polyunsaturated fatty acid content height, two saturated acylglycerol content height, fusing point or freezing point height; Reaction time is long, needs usually more than 2 days, and reaction system viscosity is big during low temperature, is not suitable for suitability for industrialized production; Also lower alcohol and grease can be reacted under fixed lipase catalyzed, product separate DG, obtain accessory substance aliphatic acid low-carbon-ester simultaneously.This reaction is rapider, and product separates easily, but product DG yield is low, and 1 mole of triacylglycerol is just won 1 mole of DG; Saturated fatty acid residue content and two saturated acylglycerol content are also high in the products obtained therefrom, thereby the product fusing point is higher, is solid-state or semisolid under the room temperature; Lower alcohol also makes the lipase inactivation easily simultaneously, shortens the biocatalyst life-span, improves production cost.

The enzymatic esterification synthetic method exists raw material of fatty acid preparation and the more problem of side reaction, obtains the product complexity, purification process complex process, energy consumption height, cost height.

And no matter glycerine solution or esterification synthetic method, in the reaction system between reactant compatibility poor, operation difficulty height, the yield of target product DG is limited, can not control the content of byproduct one acylglycerol, triacylglycerol in the product effectively; On the other hand, these react products therefrom, are the DG product that raw material reacts gained with the vegetable oil that is rich in triacylglycerol especially, the degree of unsaturation of the fatty acid residue of one-tenth ester is often lower, influence product form on the one hand, be solid or semisolid under the normal temperature, inconvenience is taken; Product polyunsaturated fatty acid content height is unfavorable for health on the other hand.

Summary of the invention

The object of the present invention is to provide a kind of high-purity, high unsaturated fatty acid residue content and low two saturated fatty acid acyl glycerol contents, the composition product that contains DG that is in a liquid state at normal temperatures.

Another object of the present invention is to provide a kind of method for preparing above-mentioned composition with enzymic catalytic reaction.

Purpose of the present invention is achieved through the following technical solutions:

A kind of composition that contains DG, the DG in the said composition (molar percentage) composed of the following components:

Dilinoleic acid acylglycerol 20～50%

Oleic acid acyl group-linoleic acid acylglycerol 20～40%

Two oleic acid acylglycerols 15～40%

Leukotrienes acyl group-linoleic acid acylglycerol 3～10%

Two palmitic acid acylglycerols 0～3%

In the above-mentioned composition that contains DG, the quality percentage composition of DG is higher than 94%, and is preferred 94～98%, and the quality percentage composition of triacylglycerol is lower than 5%, and preferred 1～4.5%; The molar percentage that saturated fatty acid residues accounts for the TFA residue is lower than 6%, preferably is lower than 5%.

Fusing point/the freezing point that contains the composition of DG depends on its aliphatic acid composition and the distribution of aliphatic acid on glycerine.The fusing point of fatty glyceride of the same race has following rule: one acylglycerol＞DG＞triacylglycerol.Be raw material with large vegetable oil directly, the DG composition fusing point that obtains by glycerolysis reaction is far above 15～20 ℃ of the fusing points of material plant oil.So, production room temperature or more be transparent aqueous DG composition under the low temperature must guarantee that its saturated fatty acid content and two saturated acylglycerol content are low.

The composition that contains DG provided by the present invention; the molar content of total saturated fatty acid residues is lower than 6%; two saturated acylglycerol content are lower than 3%, and the fusing point/freezing point of product is-15 ℃～15 ℃, to guarantee that product is in a liquid state under normal temperature condition.

For strengthening the stability that contains the composition of DG of the present invention, improve oxidation resistance, can also add some natural or synthetized oxidation preventive agents.Antioxidant is selected from one or more of following substances: TBHQ (TBHQ), n-propyl gallate (PG), butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), synthesising complex E, natural VE, Rosmarinus officinalis extract, Tea Polyphenols, phosphatide, sodium phytate, licorice, ascorbic acid, ascorbyl palmitate, citric acid; The addition of antioxidant is 0.01～0.05% of a product quality.

In addition, for strengthening the nutritive value of composition, can also add the food additives of product quality 0～0.5% to composition.Such as flavoring, sterol, sterol ester, CLA, eicosapentaenoic acid (EPA), DHA (DHA), the brilliant agent of resistance or the mixture etc. of more than one materials wherein.

Another object of the present invention provides the above-mentioned preparation of compositions method that contains DG, comprises the steps:

1. reaction raw materials one acylglycerol is joined in the reactor, be heated to 60～70 ℃, the fatty acid residue that constitutes raw material one acylglycerol consists of (molar percentage):

Palmitic acid 0～10%

Stearic acid 0～5%

Oleic acid 20～60%

Linoleic acid 20～65%

Leukotrienes 3～12%

2. specific lipase catalytic reaction: can be to add the specific lipase catalyst according to 5～15% of an acylglycerol raw material quality, stirring reaction 10～15 minutes, after having reacted, isolated by filtration product and catalyst; Perhaps reactant is reacted by the successive reaction post that is filled with the specific lipase catalyst, reactant is 3～10 minutes holdup times in post;

Described specific lipase is selected from following any one or more than one enzyme and mixes the mixture of forming with arbitrary proportion: geotrichum candidum lipase (Geotrichum candidum), aspergillus niger lipase (Aspergillusniger), Aspergillus lipase (Aspergillus sp), wrinkle Zhe lipase from candida sp (Candida rugosa), antarctic candidia lipase (Candida antarctica), Candida lipolytica lipase (Candidalypolytica), Candida parapsilosis lipase (Candida parapsilosis), look bacillus lipase (Chromobaterium viscoum), geotrichum candidum lipase (Geotrichum candidum), mucor javanicus lipase (Mucor javanicus), oat lipase (Avena s aliva) (Oatis), the blue or green mould lipase of bacterium (Penicillium sp), penicillium cammenberti lipase (camemberti) (Penicilliumcamembertii), penicillium roqueforti lipase (roqueforti) (Penicillium roquefortii), flash of light palpus mould lipase (nitens) (Phycomyces nites), pseudomonad lipase (Pseudomonas sp), the false unit cell lipase (Pseudomonas fluorescens) of fluorescence, mucor lipase (Rhizomucor), Dai Shi rizolipase (Rhizopus delemar), Java rizolipase (Rhizopus javanicus), Japan's rizolipase (Rhizopus japonicus), snow-white rizolipase (Rhizopus niveus), Rhizopus oryzae lipase (Rhizopus oryzae), Rhizopus arrhizus lipase (Rhizopus arrhizus), cotton shape is thermophilic hyphomycete lipase (Thermomyces lanuginosa);

3. product purification: remove a glycerine and an acylglycerol in the product, obtain product.

In the above-mentioned preparation of compositions method that contains DG, described specific lipase preferred immobilization geotrichum candidum lipase or immobilized candida antarctica lipase.Described reactor is selected from the tank reactor of stirring, a plurality of serial or parallel connection tank reactor and flow reactor.Flow reactor is the equipment that filler column reactor, membrane reactor etc. can carry out continuous enzymic catalytic reaction.

It is by being that the ester exchange reaction of raw material, specific lipase catalysis realizes with an acylglycerol that the present invention prepares DG.Component and proportioning as an acylglycerol of reaction raw materials are most important to the quality of finished product.In order to realize goal of the invention; obtain being under the normal temperature of high DG content, high degree of unsaturation, low two saturated acylglycerol ester contents the DG product of liquid condition, the aliphatic acid of raw material one acylglycerol of the present invention is formed should meet the percentage composition of following mole:

Palmitic acid 0～10%

Stearic acid 0～5%

Oleic acid 20～60%

Linoleic acid 20～65%

Leukotrienes 3～12%

An acylglycerol product that meets this composition can directly obtain from market, also can be to prepare voluntarily.One of preparation method divides extract body or mixture of the two and glycerine esterification with soybean/pair low vegetable seed aliphatic acid, and preparation comprised for two steps:

1. grease hydrolysis: the hydrolysis catalyst can be acid, alkali, fat hydrolase etc.The aliphatic acid that obtains of acid or basic hydrolysis needs rectification process, to improve the quality of aliphatic acid.For reducing the saturated acid content in the aliphatic acid, aliphatic acid should carry out classification to be handled.Stage division comprises that the dry method branch is carried, the solvent method branch is carried, the surfactant method branch is carried, urea bag method is separated, and the combination of their two or more methods;

2. lipase-catalyzed aliphatic acid and glycerine esterification.

In the preparation of compositions method that contains DG of the present invention, the selection of lipase, response parameter determine and DESIGN OF REACTOR to the content that improves DG in the product, reduce the triacylglycerol composition and play a very important role.

The ester exchange reaction generation DG of one acylglycerol and an acylglycerol and glycerine (MAG+MAG → DAG+Gly).Low amounts of product glycerine and DG intermiscibility are poor, easily separated, and molecular balance is shifted to the right, help the generation of product DG.

For accelerated reaction MAG+MAG → DAG+Gly carries out, avoid the generation of accessory substance triacylglycerol, reduce the content of two saturated acylglycerols, need select suitable lipase-catalyzed dose for use.Compare with chemical catalysis, the major advantage of lipase-catalyzed ester exchange reaction is the selectivity of lipase.So-called selectivity is meant the catalytic rate otherness of some reactions.The selectivity of lipase mainly refers to its position specific, Substratspezifitaet, aliphatic acid selectivity and stereocpecificity.The aliphatic acid selectivity of lipase refers to that some lipase have preferential catalytic action to certain class aliphatic acid or the acylglycerol that contains such aliphatic acid, and isopreference catalysis contains the acylglycerol of the two key unrighted acids of cis-9 as geotrichum candidum lipase (Geotrichum candidum).The aliphatic acid selectivity of lipase is by the molecular characterization of lipase and reaction system decision.When lipase-catalyzed acylglycerols such as geotrichum candidum esterase are converted into DG; the acylglycerol that preferential catalysis contains the two keys of cis-9 is converted into DG; as oleic acid one acylglycerol, linoleic acid one acylglycerol, leukotrienes one acylglycerol; the DG of preparation is rich in the unrighted acid residue that oleic acid, linoleic acid, leukotrienes etc. contain the two keys of cis-9; corresponding two saturated DG content are extremely low, and this also is to guarantee to contain the essential condition that the composition product of DG is in a liquid state at normal temperatures.Satisfy condition of the present invention specific lipase can be any one or more than one lipase of mixing of narrating in the content of the present invention.Preferred geotrichum candidum lipase or antarctic candidia lipase.

The lipase that is used to react can be that dissociate or fixing.Because immobilized lipase easily separates with product with reactant, good stability, can reuse and adorn the post successive reaction, more selecting for use in industrial production.Be applicable to that commercial immobilized lipase of the present invention has Lipozyme RM IM (immobilization mucor lipase), Lipozyme TL IM (the thermophilic hyphomycete lipase of the cotton shape of immobilization), Novozym 435 (immobilized candida antarctica lipase) etc.

To be converted into the enzymatic reaction system of DG single for an acylglycerol among the present invention, and an acylglycerol molecule is little, easily contacts with the active site of lipase, and reaction speed is fast, and it is short that an acylglycerol is converted into the time of DG, only 5～15 minutes.

In addition, by product composition, aliphatic acid composition, saturated fatty acid composition, fusing point and frying effect detection are learnt, use the product of this method preparation to meet the demands.

Compare with the production method of existing DG product or this series products, the composition and method of making the same that contains DG of the present invention has following advantage:

1. DG quality percentage composition is higher than 94% in the composition of the present invention, becomes the index of unsaturated fatty acid height of ester, and two saturated acylglycerol content are lower than 3%, and composition is in normal temperature or more clarification, transparent, easy to use under the low temperature;

2. triacylglycerol quality percentage composition is lower than 5% in the composition of the present invention, and human body or animal more can effectively suppress fat and pile up in vivo after taking in, product have better reducing blood lipid, hypotensive, prevent arteriosclerotic function.

3. production method of the present invention is a raw material with an acylglycerol, as the food emulsifying agent of consumption maximum, the large-scale industrialization production technology of an acylglycerol is simple, product purity height (＞90%), therefore this raw material cheapness, be easy to get, corresponding production cost reduces greatly;

According to above characteristics, the composition that contains DG of the present invention will can be used as the important source material of food, edible oil and fat, medicine, health products and feed.

The specific embodiment

Below by embodiment content of the present invention is further specified, among the following embodiment product analysis method is comprised:

(1) the quality percentage composition of an acylglycerol, DG, triacylglycerol in the mensuration product, employed method are U.S. oil chemistry man association's analytical methods (AOCS Official Method cd11b-91),

(2) aliphatic acid of measuring product is formed, and assay method is a gas chromatography:

Sample esterification method adopts the boron trifluoride esterification method of IUPAC;

The fatty acid compositional analysis of product adopts the IUPAC method;

Chromatographic condition:

Instrument: day U.S.'s company's 7900 gas chromatographs (N2000 binary channels chromatographic work station)

Detector: hydrogen flame ionization detector (FID)

Chromatographic column: FFAP capillary column

Column temperature: 190 ℃ of temperature of vaporization chamber: 230 ℃

Detector temperature: 230 ℃ of nitrogen flow rate: 50mL/min

Hydrogen flow rate: 50mL/min air velocity: 500mL/min

With the standard specimen qualitative analysis, quantitatively calculate with standard specimen and normalization method.

(3) utilize high performance liquid chromatograph (HPLC) that the composition product component that contains DG is analyzed and measured:

Efficient liquid chromatography instrument: Waters 600 HPLC Pump, Waters 600 HPLC Controller, WatersIn-line degasser (U.S. Waters company)

Detector: Alltech 2000ES EISD (ELSD) (U.S. Alltech company), ELSD detector: 65 ℃ of drift tube temperatures, detector gas flow rate 1.60SLPM

Chromatographic column Waters Nova-Pak C-18 Column, 3.9 * 150mm, granularity 4 μ m

Column temperature: 25 ℃

Phase flows: methyl alcohol, 1.0mL/min

Sample size: 5 μ L (5mg/ml)

Carry out qualitative and quantitative analysis with equivalent carbon number (ECN) and standard specimen.ECN=CN-2n (wherein, CN is the acyl group carbon number, and n is the unsaturated bond number on the acyl chain).

(4) Measurement of melting point

Measure the fusing point of product according to the analytical method Cc1-25 of association of U.S. oil chemistry man.

Embodiment 1

Step 1: the preparation of aliphatic acid and classification

16 kilograms of NaOH (purity 96%) are dissolved in 70 kg of water, and be added in the retort, add 100 kilograms of soybean oils, be heated to 85 ℃, stir (rotating speed 200rpm), behind the reaction 4h, add 50 kilograms of hot water, slowly add hydrochloric acid (6mol/L), with pH detection paper system pH, maintenance system acidity is dissolved (about pH5) fully until soap, continues to stir 1 hour.Standing demix takes out upper strata aliphatic acid, repeatedly washs to neutrality with 80 ℃ of hot water of 30% (mass ratio), and 80 ℃ of rotating thin film dehydration by evaporation 1 hour promptly get croude fatty acids.Croude fatty acids temperature (160 ℃), vacuum (＜10Pa) under, the acid of short-path distillation corps.

With soya bean fatty acid 60 ℃ of fusings, add solvent (acetone) in proportion and shake up (aliphatic acid/acetone, 1: 3), be incubated (15 ℃ of backs in uniform temperature, 30 minutes), progressively cooling (5 ℃/min) to temperature required (2 ℃), insulation, stir (60rpm) after a period of time (4h) obtain the paste mixture of crystallization.The crystallization paste mixture is carried out vacuum filtration.After suction filtration finished, the employing rotary evaporation removed the solvent in the liquid, promptly gets soya bean fatty acid and divides the extract body.

Step 2: the preparation of an acylglycerol

360 gram glycerine divide the extract body to mix with 2000 gram soya bean fatty acids, stir (250rpm), be heated to 60 ℃, add 200 gram immobilization mucor esterases (Rhizomucor miehei, trade name Lipozyme RMIM), vacuum (＜100Pa), reacted 40 minutes; Add 1000 gram soya bean fatty acids and divide extract body, 160 gram Lipozyme RM IM, reacted 20 minutes; The isolated by vacuum filtration catalyst, product liquid 130 ℃, vacuum (＜10Pa) remove dereaction remaining fatty acid and glycerine down, promptly get an acylglycerol raw material A, after testing, its aliphatic acid composition is as table 1:

The aliphatic acid of table 1 an acylglycerol raw material A is formed

The aliphatic acid kind	16:0	18:0	18:1	18:2	18:3	Other
							Content (mole %)	4.9	1.1	26.9	61.0	5.6	0.5

Step 3: an acylglycerol is converted into DG

In stirring reactor, add 1000 grams, one acylglycerol raw material A, be heated to 65 ℃, add 100 gram immobilization geotrichum candidum esterases (Geotrichum candidum, resin carrier), stir (200rpm), reacted 15 minutes.Isolated by filtration product and lipase-catalyzed dose, catalyst is recycling, and product is carried out purification process.100 ℃ and vacuum (＜10Pa) under the distillation condition, remove glycerine in the product; 190 ℃ and vacuum (＜5Pa) under the distillation condition, remove an acylglycerol in the product, product I.

Step 4: product analysis

(1) by mass percentage, DG quality percentage composition is 94.2%, one acylglycerol 1.7%, triacylglycerol 4.1% in the product I;

(2) molar content of saturated aliphatic acid is 4.7% in the product I;

(3) in the product I, according to molar percentage, DG consists of:

Dilinoleic acid acylglycerol 40%

Oleic acid acyl group-linoleic acid acylglycerol 31%

Two oleic acid acylglycerols 22%

Leukotrienes acyl group-linoleic acid acylglycerol 6%

Two palmitic acid acylglycerols 1%

(4) fusing point of product I :-5.2 ℃.

Embodiment 2

Method according to embodiment 1 step 1 and step 2 prepares an acylglycerol raw material, and an acylglycerol raw material A that makes is carried out following operation;

Step 1: an acylglycerol is converted into DG

500 grams, one acylglycerol A is heated to 65 ℃, and reactant is with the pillar flow reactor (strap clamp cover glass column: L=38cm, o.d.=5cm, i.d.=2.6cm, 65 ℃) of 3.0ml/min flow velocity by being filled with immobilization geotrichum candidum lipase.Product 100 ℃ and vacuum (＜10Pa) under the distillation condition, remove glycerine in the product; 190 ℃ and vacuum (＜5Pa) under the distillation condition, remove an acylglycerol in the product, product I I.

Step 4: product analysis

(1) by mass percentage, DG quality percentage composition is 95.1%, one acylglycerol 1.6%, triacylglycerol 3.2% among the product I I;

(2) molar content of saturated aliphatic acid is 4.6% among the product I I;

(3) among the product I I, according to molar percentage, DG consists of:

Dilinoleic acid acylglycerol 39%

Oleic acid acyl group-linoleic acid acylglycerol 33%

Two oleic acid acylglycerols 20%

Leukotrienes acyl group-linoleic acid acylglycerol 7%

Two palmitic acid acylglycerols 1%

(4) fusing point of product I I :-5.4 ℃.

Embodiment 3

Step 1: the preparation that two low vegetable seed aliphatic acid divide the extract body

Method is with the step 1 among the embodiment 1, and wherein soybean oil is replaced by two low rapeseed oils, promptly obtains two low vegetable seed aliphatic acid and divides the extract body.

Step 2: the preparation of an acylglycerol

360 gram glycerine divide the extract body to mix with the two low vegetable seed aliphatic acid of 2000 grams, stir (250rpm), be heated to 60 ℃, add 200 gram catalyst Lipozyme RM IM, vacuum (＜100Pa), reacted 40 minutes; Add the two low vegetable seed aliphatic acid of 1000 grams and divide extract body, 160 gram Lipozyme RM IM, reacted 20 minutes; The isolated by vacuum filtration catalyst, product liquid 130 ℃, vacuum (＜10Pa) remove dereaction remaining fatty acid and glycerine down, promptly get an acylglycerol raw material B, its aliphatic acid composition is as table 2.

The aliphatic acid of table 2 an acylglycerol raw material B is formed

The aliphatic acid kind	16:0	18:0	18:1	18:2	18:3	Other
							Content (mole %)	3.2	1.0	56.5	28.3	9.5	1.5

Step 3: an acylglycerol is converted into DG

In stirring reactor, add 1000 grams, one acylglycerol raw material B, be heated to 65 ℃, add 100 gram immobilized candida antarctica lipases (Candida antarctica, trade name Novozym 435), stir (200rpm), reacted 15 minutes.Isolated by filtration product and lipase-catalyzed dose, catalyst is recycling, and product is carried out purification process.100 ℃ and vacuum (＜10Pa) under the distillation condition, remove glycerine in the product; 190 ℃ and vacuum (＜5Pa) under the distillation condition, remove an acylglycerol in the product, product I II.

Step 4: product analysis

(1) by mass percentage, DG quality percentage composition is 96.1%, one acylglycerol 1.4%, triacylglycerol 2.5% among the product I II;

(2) molar content of saturated aliphatic acid is 3.4% among the product I II;

(3) among the product I II, according to molar percentage, DG consists of:

Dilinoleic acid acylglycerol 25%

Oleic acid acyl group-linoleic acid acylglycerol 36%

Two oleic acid acylglycerols 30%

Leukotrienes acyl group-linoleic acid acylglycerol 8.1%

Two palmitic acid acylglycerols 0.9%

(4) fusing point of product I II :-6.1 ℃.

Embodiment 4

Prepare an acylglycerol raw material by the step 1 of embodiment 3 and the method for step 2, an acylglycerol raw material B who makes carries out following step;

Step 3 acylglycerol is converted into DG

1000 grams, one acylglycerol raw material B is heated to 65 ℃, and reactant is with the pillar flow reactor (strap clamp cover glass column: L=38cm, o.d.=5cm, i.d.=2.6cm, 65 ℃) of 3.0ml/min flow velocity by being filled with Novozym 435.Product 100 ℃ and vacuum (＜10Pa) under the distillation condition, remove glycerine in the product; 190 ℃ and vacuum (＜5Pa) under the distillation condition, remove an acylglycerol in the product, product I V.

Step 4: product analysis

(1) by mass percentage, DG quality percentage composition is 97.1%, one acylglycerol 1.9%, triacylglycerol 1.0% among the product I V;

(2) molar content of saturated aliphatic acid is 3.3% among the product I V;

(3) among the product I V, according to molar percentage, DG consists of:

Dilinoleic acid acylglycerol 24%

Oleic acid acyl group-linoleic acid acylglycerol 37.3%

Two oleic acid acylglycerols 29.4%

Leukotrienes acyl group-linoleic acid acylglycerol 8.4%

Two palmitic acid acylglycerols 0.9%

(4) fusing point of product I V :-6.2 ℃.

Embodiment 5

Step 1: prepare an acylglycerol raw material

Respectively according to the step 1 of embodiment 1 and embodiment 3,2 preparation one acylglycerol raw material A and raw material B, the raw material A that makes and raw material B are mixed, evenly by mass ratio at 1: 1, make an acylglycerol raw material C.

Step 2: an acylglycerol is converted into DG

800 grams, one acylglycerol raw material C is heated to 65 ℃, and reactant is with the pillar flow reactor (strap clamp cover glass column: L=38cm, o.d.=5cm, i.d.=2.6cm, 65 ℃) of 3.0ml/min flow velocity by being filled with immobilization geotrichum candidum lipase.Product 100 ℃ and vacuum (＜10Pa) under the distillation condition, remove glycerine in the product; 190 ℃ and vacuum (＜5Pa) under the distillation condition, remove an acylglycerol in the product, product V.

Step 4: product analysis

(1) by mass percentage, DG quality percentage composition is 96.8%, one acylglycerol 2.1%, triacylglycerol 1.2% among the product V;

(2) molar content of saturated aliphatic acid is 3.6% among the product V;

(3) among the product V, according to molar percentage, DG consists of:

Dilinoleic acid acylglycerol 40%

Oleic acid acyl group-linoleic acid acylglycerol 28%

Two oleic acid acylglycerols 23%

Leukotrienes acyl group-linoleic acid acylglycerol 8%

Two palmitic acid acylglycerols 1%

(4) fusing point of product V :-5.8 ℃.

The comparative example 1: the oxidation stability test that contains the composition of DG

With the refined soybean oil is contrast, utilizes active oxygen method (being called for short AOM) to estimate the oxidation stability of the composition of DG of the present invention.

Method: get respectively 20mL according to product V, the 20mL DG V of the preparation of the method for embodiment 5 and 100ppm antioxidant (TBHQ), 20mL refined soybean oil, 20mL refined soybean oil and 100ppm antioxidant (TBHQ) in the test tube of certain volume; under 97.8 ℃ temperature conditions, feed to do clean air (2.33ml/s), required time (title AOM value) when reaching 100meq/kg with the titration measuring peroxide value.The AOM value is high more, and is oxidation-stabilized good more.The AOM value of four kinds of samples the results are shown in Table 3.

The AOM value of table 3 product V and refined soybean oil

Sample	The AOM value (hour)
		Refined soybean oil refined soybean oil+100ppmTBHQ product V product V+100ppmTBHQ	6.3 17.4 5.9 17.1

As seen from the above table: the oxidation stability of composition product V that contains DG is slightly poor than refined soybean oil, but after adding antioxidant TBHQ, its oxidation stability and refining soybean close.

The comparative example 2: the frying test

(1) test objective: with traditional frying oil (palm oil) is benchmark, the frying performance when estimating the composition that contains DG of the present invention as edible oil, the product I V that product of the present invention adopts the method for press embodiment 4 to prepare.

Product I V and this product and palm oil were mixed with three kinds of frying experiments in 1: 1 and 3: 7 with oily by mass ratio, be labeled as a, b, c respectively, and interpolation antioxidant (TBHQ) 150ppm and 100ppm citric acid, the frying French fries are made analysis according to national standard (organoleptic analysis's method GB 12315-90) to the organoleptic quality of frying French fries.

(2) test method: three kinds of feedstock oils that are used for frying of a, b, c of 1500mL are heated to 150 ± 2 ℃ at the electric food warmer with attemperating unit, fried continuously every day 8 hours, fried altogether 4 days.Close fryer when finishing every day, and feedstock oil filters at once, after will filtering in second day oil pour in the pot, replenish green oil again and make in the pot identical oil mass is arranged every day.The frying time of every batch of French fries (25g) is 3 minutes, per hour fries 6 batches of French fries and amounts to 150g.Taking out the 50mL oil sample with 2 hours interval of continuous frying tests.

(3) analysis of experiments: sensory evaluation is with reference to GB 12315-90 organoleptic analysis method (ranking method).The fried ripe back of food drop oil, cooling are reduced to room temperature with what perform an analysis with the preservative film sealing.The organoleptic analysis forms hobby type sensory evaluation group by 10 valuation officers, check forward direction valuation officer illustrates purpose, the method for inspection and the decision criteria of check, so that each valuation officer has unified understanding to the criterion of checking, subsequently with at random order to every valuation officer's sampling, and provide can be for reference food, as shown in table 4.

Table 4 is with reference to the evaluation score of food

Texture characteristic	Mark	With reference to food
			Fragility (crisp brittleness)	0	Ripe noodles
10	Potato chips
		Hardness		0	Egg is white
10	Peanut
			Coherency	0	Cake
10	Raisins
		Oiliness		0	Watermelon
10	Cream

(4) variation of frying oil iodine value in the frying process

A, b, the iodine value variation in 4 days frying process of three kinds of fryings of c feedstock oil see Table 5.By test data as can be known, the iodine value of three kinds of frying feedstock oils all constantly reduces in whole frying process, but variation tendency is more or less the same, and the speed of reduction is roughly the same.

The iodine value of table 5 oil sample changes

The frying time (h)	IV(gI/100g)
				a	b	c
	2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32	133.00 130.08 128.07 127.32 127.57 124.72 120.65 121.09 121.30 121.78 120.21 119.37 114.43 118.98 112.34 115.27	83.13 83.66 83.76 78.29 80.60 76.12 78.19 75.56 73.78 71.97 72.44 69.10 64.14 67.13 62.62 65.28				64.41 61.65 59.79 58.69 62.22 56.83 58.77 55.12 54.53 53.70 55.93 52.45 52.77 51.28 49.37 50.01

(5) variation of frying oil peroxide value in the frying process

The variation of a, b, c three kinds of fryings feedstock oil peroxide value in 4 days frying process sees Table 6.By test data as can be known, along with the prolongation of frying time, peroxide value constantly increases, and the increase trend of feedstock oil b is a little more than feedstock oil a, c.

The peroxide value of feedstock oil in the table 6 frying process

The frying time (h)	POV(meq/kg)
				a	b	c
	2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32	7.29 7.56 8.20 9.00 11.52 12.78 12.91 14.20 13.81 15.79 15.21 16.79 17.34 16.69 17.55 17.59	9.50 8.65 10.27 11.20 13.00 14.34 15.69 17.91 17.20 18.66 21.37 19.84 23.96 22.45 23.12 25.05				7.92 8.98 10.21 11.62 12.26 11.74 13.01 12.14 14.39 15.92 16.10 16.45 17.28 18.73 20.13 18.19

(6) variation of frying oil anisidine value in the frying process

The variation of a, b, c three kinds of fryings feedstock oil anisidine value in 4 days frying process sees Table 7.By test data as can be known in the process of whole frying, anisidine value in time prolongation and increase, wherein the variation tendency of feedstock oil a and c is close substantially.

The anisidine value (p-A.V) of feedstock oil in the table 7 frying process

The frying time (h)	p-A.V
				a	b	c
	2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32	59.45 53.27 60.72 64.19 70.91 78.64 85.43 92.57 100.01 113.92 124.7 137.28 144.52 157.97 169.44 189.4	77.58 79.43 81.92 85.78 95.67 107.24 117.75 123.67 129.91 137.28 144.78 159.51 165.77 177.4 185.2 197.39				53.48 54.76 60.94 66.13 72.47 80.25 90.93 94.56 104.2 120.9 130.4 140.78 151.46 160.72 174.11 191.17

(7) variation of frying oil acid value in the frying process

A, b, the acid value variation in 4 days frying process of three kinds of fryings of c feedstock oil see Table 8.By test data as can be known, in the frying process, acid value prolongation in time constantly increases, and the acid value of three kinds of feedstock oils increases the trend basically identical.

The acid value (AV) of feedstock oil in the table 8 frying process

The frying time (h)	AV(mg KOH/g)
				a	b	c
	2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32	0.43 0.53 0.51 0.77 0.87 0.92 1.03 1.11 1.31 1.37 1.42 1.49 1.59 1.62 1.67 1.73	0.62 0.75 0.87 0.97 1.06 1.07 1.23 1.31 1.34 1.45 1.47 1.52 1.67 1.74 1.83 1.86				0.33 0.45 0.5 0.6 0.7 0.74 0.85 0.91 1.33 1.35 1.4 1.37 1.45 1.47 1.54 1.49

(8) fragility of fried food (crisp brittleness) sensory evaluation

Every valuation officer the results are shown in Table 9 for the rank of the ordering of food brittleness.

The rank and the sum of ranks of table 9 sample fragility (crisp brittleness)

The valuation officer	Sample			Sum of ranks
					a	b	c
	1 2 3 4 5 6 7 8 9 10	3 3 3 3 1 2 2 1 2 1	1 1 2 2 3 3 1 2 3 3					2 2 1 1 2 1 3 3 1 2	6 6 6 6 6 6 6 6 6 6
Every kind of sample sum of ranks				21	21	18	60

Use the Friedman check to whether there being the conspicuousness difference to decision making compute statistics F between the test sample: $F=\frac{12}{\mathrm{JP}(P+1)}({R_1}^2+{R_2}^2+\·\·\·+{R_P}^2)-3J(P+1)$

In the formula: J-valuation officer's number;

P-sample (or product) number;

R ₁, R ₂... R _pThe sum of ranks of-every kind sample.

As shown from the above formula, F=0.6, corresponding J=10, P=3, the critical value of a=0.05 is 6.20, so can think, the fragility of these 3 kinds of French fries (crisp brittleness) does not have the conspicuousness difference under 0.05 level of signifiance.

(9) fried food hardness sensory evaluation

Every valuation officer the results are shown in Table 10 to the rank of the ordering of food hardness:

The rank and the sum of ranks of table 10 sample hardness

The valuation officer	Sample			Sum of ranks
					a	b	c
	1 2 3 4 5 6 7 8 9 10	1 2 3 3 3 2 1 2 1 1	3 3 2 2 2 3 3 3 3 3					2 1 1 1 1 1 2 1 2 2	6 6 6 6 6 6 6 6 6 6
Every kind of sample sum of ranks				19	27	14	60

F=8.6, corresponding J=10, P=3, the critical value 8.60 of a=0.01, so can think, the hardness of these 3 kinds of French fries has certain difference on 0.01 level of signifiance.

Be arranged as from small to large according to various kinds product sum of ranks: c, a, b, calculate critical value γ (I, α), according to formula:

$\mathrm{\γ}(I,\mathrm{\α})=q(I,\mathrm{\α})\sqrt{\frac{\mathrm{JP}(P+1)}{12}}-$

γ(3，0.01)＝q(3，0.01)×3.16＝4.12×3.16＝13.0

γ(2，0.01)＝q(2，0.01)×3.16＝3.64×3.16＝11.5

Relatively with grouping:

R _B-R _C＝27-14＝13＝γ(3，0.01)＝13.0

R _B-R _A＝27-19＝12＞γ(2，0.01)＝11.5

R _A-R _C＝19-14＝5＜γ(2，0.01)＝11.5

More than Bi Jiao result is as follows:

Be divided into two groups at last: C ab

Presentation of results: the hardest with the French fries of the fried system of feedstock oil b on 1% the level of signifiance, French fries there was no significant difference on hardness of the fried system of feedstock oil a and c.

(10) fried food coherency sensory evaluation

Every valuation officer the results are shown in Table 11 for the rank of the coherent ordering of food.

Coherent rank of table 11 sample and sum of ranks

The valuation officer	Sample			Sum of ranks
					a	b	C
	1 2 3 4 5 6 7 8 9 10	1 2 1 3 1 2.5 2 2 2 3	2 3 3 2 3 2.5 3 3 3 2					3 1 2 1 2 1 1 1 1 1	6 6 6 6 6 6 6 6 6 6
Every kind of sample sum of ranks				19.5	26.5	14	60

Owing to there is the valuation officer can not distinguish two kinds of difference between the sample, two kinds of samples are ranked at same rank, use F ' replacement F this moment, and the computational methods of F ' are formula as follows:

$F^{\′}=\frac{F}{1-\{E/[\mathrm{JP}(P^2-1)\left]\right\}}$

F=7.85, thus F '=8.12, corresponding J=10, P=3, the critical value 6.20 of a=0.05, so can think, the coherency of these 3 kinds of French fries has the conspicuousness difference on 0.05 level of signifiance.

Be arranged as from small to large according to various kinds product sum of ranks: c, a, b, calculating critical value γ (I, α):

γ(3，0.05)＝q(3，0.05)×3.16＝3.31×3.16＝10.5

γ(2，0.05)＝q(2，0.05)×3.16＝2.77×3.16＝8.8

Relatively with grouping:

R _B-R _C＝26.5-14＝12.5＞γ(3，0.05)＝10.5

R _B-R _A＝26.5-19.5＝7＜γ(2，0.05)＝8.8

R _A-R _C＝19.5-14＝5.5＜γ(2，0.05)＝8.8

Be divided into three groups at last: c, a, b

Presentation of results: on 5% the level of signifiance, best with the French fries coherency of the fried system of feedstock oil b, feedstock oil a takes second place, and the French fries coherency of the fried system of feedstock oil c is the poorest.

(11) fried food oiliness sensory evaluation

Every valuation officer the results are shown in Table 12 for the rank of the ordering of food oiliness.

The rank and the sum of ranks of table 12 sample oiliness

The valuation officer	Sample			Sum of ranks
					a	b	c
	1 2 3 4 5 6 7 8 9 10	2 3 2 1 1 1 2.5 3 3 3	1 2 1 2 3 3 1 1 1 1					3 1 3 3 2 2 2.5 2 2 2	6 6 6 6 6 6 6 6 6 6
Every kind of sample sum of ranks				21.5	16	22.5	60

Owing to there is the valuation officer can not distinguish two kinds of difference between the sample, two kinds of samples are ranked at same rank, use F ' replacement F this moment, calculate F '=2.51 as can be known, corresponding J=10, P=3, the critical value 6.20 of a=0.05, so the oiliness of these 3 kinds of French fries does not have the conspicuousness difference on 0.05 level of signifiance.

(12) investigation of fried food shelf life

Preserve and the deterioration condition of high temperature (70 ℃) high humidity is investigated the rotten situation of the French fries after the frying respectively with normal temperature.

A. the shelf life of French fries is investigated under the normal temperature situation

Getting French fries drop oil, the cooling of a certain amount of same batch (frying the 4th hour sample continuously), place the beaker of 250mL, seal with preservative film, preserve under 10～20 ℃ room temperature, is the termination time when occurring going mouldy with it.Three kinds of samples mildew occurs when being saved in the 4th day, do not have notable difference on the time.

B. the shelf life of French fries is investigated under the deterioration condition

Getting French fries drop oil, the cooling of a certain amount of same batch (frying the 9th hour sample continuously), place the beaker of 250mL, seal with preservative film, preserve under 70 ℃ high temperature, and keep higher levels of humidity, is the termination time when the look change occurring with it.A sample color burn at first after preserving 7.5 hours, b, c sample generation look become after preserving 9 hours, and food is dark brown.

By above-mentioned sensory evaluation result of the test as can be known: frying performance and traditional frying oil (palm oil) no significant difference that contains the composition of DG of the present invention.

Claims (6)

1. a composition that contains DG is made up of an acylglycerol, DG and triacylglycerol, it is characterized in that: by mole percentage, described DG is composed of the following components:

Dilinoleic acid acylglycerol 20～50%

Oleic acid acyl group-linoleic acid acylglycerol 20～40%

Two oleic acid acylglycerols 15～40%

Leukotrienes acyl group-linoleic acid acylglycerol 3～10%

Two palmitic acid acylglycerols 0～3%

2. the composition that contains DG according to claim 1; the quality percentage composition that it is characterized in that DG in the said composition is higher than 94%; the quality percentage composition of triacylglycerol is lower than 5%; become in the TFA residue of ester, the molar content of saturated fatty acid residues is lower than 6%.

3. the composition that contains DG according to claim 1, the quality percentage composition that it is characterized in that DG in the said composition is 94～98%, the quality percentage composition of triacylglycerol is 1～4.5%; The molar percentage that saturated fatty acid residues accounts for the TFA residue is lower than 5%.

4. the preparation of compositions method that contains DG according to claim 1 comprises the steps:

1. reaction raw materials one acylglycerol is joined in the reactor, be heated to 60～70 ℃, the fatty acid residue that constitutes raw material one acylglycerol consists of (molar percentage):

Palmitic acid 0～10%

Stearic acid 0～5%

Oleic acid 20～60%

Linoleic acid 20～65%

Leukotrienes 3～12%

2. specific lipase catalytic reaction: can be to add the specific lipase catalyst according to 5～15% of an acylglycerol raw material quality, stirring reaction 10～15 minutes, after having reacted, isolated by filtration product and catalyst; Perhaps reactant is reacted by the successive reaction post that is filled with the specific lipase catalyst, reactant is 3～10 minutes holdup times in post;

Described specific lipase is selected from following any one or more than one enzyme and mixes the mixture of forming with arbitrary proportion: geotrichum candidum lipase, aspergillus niger lipase, Aspergillus lipase, wrinkle Zhe lipase from candida sp, antarctic candidia lipase, Candida lipolytica lipase, Candida parapsilosis lipase, look bacillus lipase, geotrichum candidum lipase, mucor javanicus lipase, oat lipase, the mould lipase of blue or green bacterium, penicillium cammenberti lipase, penicillium roqueforti lipase, the mould lipase of flash of light palpus, pseudomonad lipase, the false unit cell lipase of fluorescence, mucor lipase, the Dai Shi rizolipase, the Java rizolipase, Japan's rizolipase, snow-white rizolipase, Rhizopus oryzae lipase, Rhizopus arrhizus lipase, the thermophilic hyphomycete lipase of cotton shape;

3. product purification: remove a glycerine and an acylglycerol in the product, obtain product.

5. the preparation of compositions method that contains DG according to claim 4 is characterized in that described specific lipase is immobilization geotrichum candidum lipase or immobilized candida antarctica lipase.

6. the preparation of compositions method that contains DG according to claim 4 is characterized in that described reactor is selected from the tank reactor of stirring, a plurality of serial or parallel connection tank reactor and flow reactor.