CN104059897A

CN104059897A - Plantrennet and application thereof

Info

Publication number: CN104059897A
Application number: CN201410312404.4A
Authority: CN
Inventors: 黄艾祥; 陶亮; 张亚丽
Original assignee: Yunnan Agricultural University
Current assignee: Yunnan Agricultural University
Priority date: 2014-07-02
Filing date: 2014-07-02
Publication date: 2014-09-24

Abstract

The invention relates to plantrennet and the application thereof, and belongs to the technical field of food science. The molecular weight of the plantrennet is 30 KDa and 26 KDa. Sulfydryl is the main functional group of an enzyme. The enzymatic characteristics of the plantrennet are that curd activity and protein decomposition activity are provided, the optimum temperature of the enzyme is 85 DEG C, the optimum protein decomposition activity temperature ranges from 75 DEG C to 80 DEG C, the enzyme activity pH value ranges from 4.0 to 11.0, the optimum enzyme activity pH value is 8.0, oxidation resistance and reducing capacity of the enzyme are weak, and metal ions influence enzyme activity. In mass, 60% of plantrennet, 30% of calcium chloride and 10% of citric acid are mixed to prepare a 0.15% water solution according to the mass ratio, and the water solution is used as a milk coagulant and is applied into cheese processing with the mass accounting for 30% of raw milk mass. The plantrennet has the advantages of being high in yield, good in quality, safe, efficient, stable in enzymatic property, wide in application range, simple in using method, capable of being applied into chess processing and wide in prospect in biological agent development.

Description

A kind of plant protease and application thereof

Technical field:

The present invention relates to a kind of plant protease and application thereof, belong to technical field of food science.

Background technology:

Yunnan is famous Kingdom of Animals and Plants, and strong province of Biological resources is Yunnan Province's development strategic objective.According to investigations, in Northwest Yunnan, there is a kind of popular name (to record according to Yunnan plant will the natural vine plant of " Herba seu Radix Metaplexis hemsleyanae ", belong to Asclepiadaceae, South Mountain Calamus, climb woody climber, grow in 500～3000 meters of montanes of height above sea level or thicket), break its stem into pieces the rear aqueous solution with warm water soaking and there is curdled milk function, local milk goat raiser is milk coagulant processing goat milk cake with it, and product has special fragrant, is of high nutritive value.Breast cake is one of national milk-product of Yunnan three great traditions (newborn cake, breast fan, butter), conventionally fresh milk is after heat-sterilization, add milk coagulant, make protein condenses, then enter after moulding is squeezed in mold pressing and make, some foreigner is called " sino type cheese " visually, and advantages for development are obvious, market outlook are wide.

Along with the concern of people to food-safety problem, living contaminants problem, the rennin shortage of cheese starter and the safety problem of chemosynthesis milk coagulant of traditional acid cure agent of processing for newborn cake, milk coagulant is had higher requirement, and development of new milk coagulant is imperative." Herba seu Radix Metaplexis hemsleyanae " research is the inevitable of Yunnan Biological resources exploitation as milk coagulant, the inventor " is passed through muscle rattan milk-clotting mechanism research (31160331) " as relying on taking state natural sciences fund, complete the research to " Herba seu Radix Metaplexis hemsleyanae " main curdling component, character and utilisation technology thereof, now proposed patent application.

By literature search, have no the open report identical with the present invention.

Summary of the invention:

The object of the invention is to develop Yunnan plant resource, a kind of stdn, safe and efficient, simple and practical plant protease and application thereof be provided.

Plant protease of the present invention is prepared according to a conventional method, and molecular weight and enzymatic property are as follows:

The molecular weight of this plant protease is 30KDa and 26KDa, and sulfydryl is the major function group of enzyme;

The enzymatic property of this plant protease: there is curdled milk vigor and Proteolytic activity, 85 DEG C of the optimum temperutures of enzyme, optimum protein decompose 75-80 DEG C of vigor temperature, enzyme pH value alive 4.0-11.0, optimal pH 8.0, anti-oxidant, the reducing power of enzyme a little less than, metal ion affects enzyme activity.

The application of plant protease of the present invention: get in mass ratio plant protease 60%, calcium chloride 30%, citric acid 10% and mix, then be mixed with in mass ratio 0.15% aqueous solution; This aqueous solution is applied in newborn cake processing by 30% of raw milk quality as milk coagulant.

The invention has the advantages that:

A. the Herba seu Radix Metaplexis hemsleyanae resource that develops rich brown, plant protease cost is low.

B. can realize the standardized production of product, the advantage such as that proteolytic enzyme has is safe and efficient, zymologic property is stable, applied range, using method are simple.

C. enriched China's foodstuff additive kind, product decapacitation is applied in newborn cake, cheese, bean product, in the exploitation of biotechnological formulation, has a extensive future.

Embodiment:

1, plant protease of the present invention obtains through the following step:

(1) raw material and pre-treatment: take without going mouldy, without the air-dry Herba seu Radix Metaplexis hemsleyanae stem 10kg of dust, get express developed with clear water after cut-out, drain away the water, break into pieces and be 1-2cm ³particle

(2) soak: add 200kg distilled water, with 58 DEG C of water-baths immersion 30min.

(3) removal of impurity: by 4 layers of filtered through gauze, filtrate is again through the centrifugal fine impurity (5000r/min, 15min) of removing.

(4) concentrated: vacuum concentration is to 15% (55, DEG C-0.075MPa) of original volume in rotatory evaporator for filtrate, and concentrated solution is about 30kg, and is cooled to 0-4 DEG C.

(5) extract proteolytic enzyme: in cooling concentration liquid, slowly adding ammonium sulfate to saturation ratio is 20%, aging (4 DEG C, 20min), centrifugal (5000r/min, 5min); Getting supernatant liquor, again to add ammonium sulfate to saturation concentration be 60%, and aging (4 DEG C, 20min), centrifugal (5000r/min, 15min), abandon supernatant liquor.

(6) the dry purifying of proteolytic enzyme: abandon the phosphate buffer solution that adds 600mL pH8.0 in the proteolytic enzyme after supernatant liquor, put into dialysis tubing, dialysis tubing is immersed to the purifying 20h that dialyses in distilled water, every 4h changes water once.Proteolytic enzyme is put into plastics or stainless steel vessel-80 DEG C of refrigerator quick-frozens, vacuum lyophilization (vacuum tightness 1pa, condenser temperature-60 DEG C, sample temperature-40-20 DEG C), proteolytic enzyme dried powder.

(7) plant protease that the present embodiment obtains has following feature: finished product protease 3 4.38g, and 85 DEG C of its optimum temperutures, optimum protein decomposes vigor temperature 75-80 DEG C, enzyme pH value alive 4.0-11.0, optimal pH 8.0, metal ion affects enzyme activity, anti-oxidant, the reducing power of enzyme a little less than.

2, the application of plant protease

(1) preparation of plant protease milk coagulant

Take proteinase 9 g, calcium chloride 4.5g, citric acid 1.5g, add 9985g water, being mixed with 10kg concentration is 0.15% milk coagulant.

(2) newborn cake processing

1. fresh milk: select the raw goat milk 30kg of fresh high-quality of healthy milk goat secretion, acidity≤14 ⁰t;

2. filtering and impurity removing: be preheated to 40 DEG C, with the impurity in two-layer gauze filtering Ruzhong;

3. heat-sterilization: be heated to 90 ± 2 DEG C, kill the harmful microorganism in Ruzhong, notice preventing that sticky pot is charred.

4. add the solidifying agent of enzyme: after being cooled to 85 DEG C, add plant protease milk coagulant 9kg, mix;

5. curdled milk: 85 DEG C, insulation 10min, when smooth to grumeleuse, hard, tangent plane is neat;

6. discharging whey: grumeleuse chopping is to 4-5cm with cutters ³, whey is separated out;

7. extrusion molding: grumeleuse wraps up with fine cloth, extruding discharging whey, stone pressurization for tradition, this experiment adopts the extrusion molding of the newborn cake forming machine of self-control;

8. quality inspection: the heavy 4.155kg of newborn cake, yield rate 13.85%, and it is carried out to sense organ, physics and chemistry and sanitary index inspection, the results are shown in Table 1, table 2.

9. finished product

The organoleptic feature of the newborn cake of table 1

The physical and chemical index of the newborn cake of table 2

Claims

1. a plant protease, is characterized in that:

(1) molecular weight of this plant protease is 30KDa and 26KDa, and sulfydryl is the major function group of enzyme;

(2) enzymatic property of this plant protease: there is curdled milk vigor and Proteolytic activity, 85 DEG C of the optimum temperutures of enzyme, optimum protein decompose 75-80 DEG C of vigor temperature, enzyme pH value alive 4.0-11.0, optimal pH 8.0, anti-oxidant, the reducing power of enzyme a little less than, metal ion affects enzyme activity.

2. the application of plant protease claimed in claim 1, is characterized in that: get in mass ratio plant protease 60%, calcium chloride 30%, citric acid 10% and mix, then be mixed with in mass ratio 0.15% aqueous solution; This aqueous solution is applied in newborn cake processing by 30% of raw milk quality as milk coagulant.