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Double wall tank OTK-6 for milk fermentation

  • Added: 03.07.2014
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Contents

INTRODUCTION

KEFIR PREPARATION TECHNOLOGY

LINE DESCRIPTION

PROCESS EQUIPMENT

Dairy tank B2-OMG-

Centrifugal pump NMU-

Automated plate pasteurization and cooling unit PLOP-

Plate pasteurizer

OMA-3M milk separator-cleaner

Homogenizer A1-OGM

Tank G6-OPB-1000 for pasteurized milk maintenance

NRM-2 gear pump with internal engagement

Double wall tank OTK-6 for milk fermentation

Packing and packing machine M6-OPZ-E

PROCESS CALCULATION

Raw material consumption and output of finished product

Calculation and selection of process equipment

Calculation of workshop area

DESIGNATIONS FOR EQUIPMENT AND MACHINE DIAGRAM OF KEFIR PRODUCTION LINE

DESIGNATIONS FOR MACHINE AND HARDWARE DIAGRAM OF KEFIR SHOP

CONCLUSION

LIST OF LITERATURE USED

Introduction

Kefir is one of the most popular sour milk diet drinks and rightfully occupies a dominant position among all milk processing products.

The birthplace of kefir is the North Caucasus, where it was made for a long time in burduks or in wooden cadets. The technology of its manufacture in bottles is simple - kefir fungi are poured with steamed milk cooled to 1820 0C, during the process of fermentation and ripening, the product is periodically whipped. When kefir ripens, due to increased aeration, yeast actively develops, which affects the taste and consistency of the product: the consistency becomes liquid, sour cream, the taste is specific, acidic, acquires sharpness.

In Russia, kefir was produced back in 18661867. artisanal method on fungi brought from the Caucasus in dry form. Kefir fungi were revived in boiled chilled defatted milk and used to prepare starters. The kefir milk was heated to 1623 0C and fermented with starter directly fused from the fungi. After obtaining the clot, the bottles were agitated to accelerate the process of beverage formation and kept indoors at a temperature of 1416 0C for a day, and sometimes for a longer time.

According to the same technology, kefir was produced at city dairy plants, while pasteurization of milk and bottling of the drink into bottles with a sealed closure were used.

As a result of the duration of the technological process, the labor intensity of many operations, the production of kefir was limited and the demand of the population for it was not satisfied, so in the 30s of the twentieth century. the technology of kefir was changed: it began to be produced in an accelerated way, which later received the name of the thermostat .

Milk going to the production of kefir began to be bored at high temperatures in thermostats without shaking and corresponding accumulation of yeast fermentation products. As a result of the change in technology, instead of a soft semi-liquid drink with a characteristic refreshing taste, factories began to produce a product with a dense clot, which tastes like downtown.

As a result of a number of research works, a reservoir method for the production of kefir has been developed, which is now widely recognized and widely introduced in the dairy industry.

The purpose of my work is to consider a typical process line for the production of kefir by a tank method with the cooling of the product in a milk fermentation tank and packing into polyethylene bags. This process line is widely used for the production of kefir both at enterprises of the Sverdlovsk region and throughout the country and allows you to obtain a product with good taste and organoleptic qualities that meet the requirements of regulatory documents.

Kefir preparation technology

There are two methods for the production of kefir - reservoir and thermostat. The reservoir production method differs from the thermostatic one in that milk is bored in a large capacity and a product with mixed clot is sent for bottling. The technological process consists of the following operations: acceptance and preparation of raw materials, normalization, homogenization, pasteurization and cooling, fermentation in special tanks, clot cooling, clot ripening, packing.

Raw materials.

Kefir is produced by reservoir method from whole natural normalized milk not lower than the second grade, with acidity not more than 19 0T, density not less than 1.0278 kg/m3, with different weight fraction of fat, therefore initial milk is normalized to the required weight fraction of fat. When whole milk is normalized by fat, there can be two options: fat in whole milk is more than is required in production, and fat in whole milk is less than is required. In the first version fat is partially taken by separation or fat-free is added to initial milk. In second version cream is added to increase fat content of initial milk. One of the simplest methods of fat normalization is normalization by mixing calculated amounts of normalized milk and a normalizing component (cream or defatted milk) in a container while thoroughly mixing the mixture.

Heat treatment and homogenization.

Pasteurization of milk is carried out in order to eliminate vegetative forms of microflora, including pathogenic ones. The most common method in the production of fermented milk products is short-term pasteurization at a temperature of 8587 0C with holding for 510 minutes or at 9092 0C with holding for 2-3 minutes with subsequent cooling to the fermentation temperature. The pasteurization regime should ensure that the desired properties of the finished product are obtained, in particular organoleptic indices (taste, desired viscosity and clot density). High pasteurization temperatures cause denaturation of serum proteins, while increasing the hydration properties of casein. This contributes to the formation of a denser clot that holds moisture well, which prevents the separation of serum during storage .

Homogenization is the fragmentation (dispersion) of fat beads by exposing milk to significant external forces. During processing, the size of the fat beads and the rate of surfacing are reduced. The shell substance of the fat ball is redistributed, the fat emulsion is stabilized, and homogenized milk is not settled. Currently, two-stage homogenization is used, which prevents sticking of particles of fat balls at the outlet of the valve slot of the homogenizing head. Homogenization is carried out at a temperature of 6065 0C and a pressure of 1517.5 MPa (125175 atm). After pasteurization and homogenization, the mixture is cooled to the fermentation temperature.

Fermentation and fermentation of milk.

In the production of kefir, starter prepared on kefir fungi is usually used. Their main representatives are lactic acid sticks, lactic streptococci, including fragrance-forming and milk yeast of the Torula type. Random grain microflora consists of spore sticks, acetic acid bacteria, milk molds, film yeast, Coli group bacteria, etc.

To prepare kefir starter, dry kefir grains are kept in warm water (2530 0C) during the day, changing it 2-3 times during this time. Then water is drained, and swollen grains are poured with warm milk taken in tenfold amount relative to volume of fungi.

To produce kefir with characteristic taste and strong consistency, it is necessary to use a production starter aged after fermentation at a temperature of 1012 0C for 1224 hour. The starter, which is typically 5% by weight of the fermented mixture, is added to the mixture cooled to the fermentation temperature. The mixture is bored at a temperature of 2325 0C to form a milk-protein clot with acidity of 80100 0T (pH 4.54.65). During digestion, sourdough microflora multiplies, acidity increases, casein coagulates and a clot forms. After completion of the digestion, the product is immediately cooled.

Agitation and cooling of the clot.

After fermentation, the kefir is stirred and cooled to ripening temperature. The product is stirred after 6090 minutes after the start of its cooling time and is carried out for 1030 minutes. The clot mixed and cooled to a temperature of 20 0C was left alone.

Kefir maturation.

The duration of kefir maturation is 610 hours. During maturation, yeast is activated, alcohol fermentation occurs, as a result of which alcohol, carbon dioxide and other substances giving this product specific properties are formed in the product.

Stirring and bottling.

After the maturation time has elapsed, the kefir in the tank is stirred for 210 minutes before the start of dispensing.

Packing and marking shall be carried out in accordance with the requirements of the standard for this product. In order to improve the consistency of the finished product, it is recommended that the packed kefir be maintained in the refrigerating compartment before implementation. When the kefir reaches the required value of conditional viscosity and temperature of 6 0С, the technological process is considered completed and the product is ready for implementation .

Line Description

Let us consider the main process diagram of kefir production by tank method with cooling in tanks. According to this scheme, milk is supplied by pumps through pipes, and the packaged finished product is supplied by intra-plant transport (chain and belt conveyors, etc.).

In heat exchangers, milk and beverages are heat treated (heated and cooled) to a predetermined temperature. Milk is purified from mechanical impurities in separator-cleaners in flow and treated in homogenizers to obtain appropriate dispersion of fat and improve viscosity of beverage.

The beverage in the tank is mixed with a drive stirrer. Beverage is packed in film package or cardboard bags on casting machines and machines.

Process monitoring and control are automated.

We will analyze the specific production line.

The milk normalized on fat content cooled up to 4-6 0C from the molokokhranitelny V2OMG10 tank with a capacity of 10 thousand l the centrifugal pump NMU6 is served in a balancing tank of pasterizatsionnookhladitelny OPL5 installation and further the pump NMU6 goes to the I section of regeneration of the heat exchanger from where warmed up up to 3035 0C comes to the central tube of a separatoramolokoochistitel of OMA-3M. Purified milk under pressure created by the pressure disk of the separator is supplied to section II of heat exchanger regeneration, then it is sent to pasteurization section for heating up to 85 0С and supplied to tank G6OPB1000, where it is kept at this temperature for 510 minutes. Milk is sent from the tank by gravity to the A1OGM homogenizer, wherein at a pressure of 125175, the at is homogenized and fed to the second heat exchanger section to return heat to the counter milk flow. The milk cooled up to the temperature of a zakvashivaniye (2325 0C) comes to the double-walled OTK6 tank where previously by means of the pump HPM2 ferment gets. The digestion takes place to an acidity of 8590 0T, then the clot is mixed and immediately cooled with cold water to 20 0C. Subsequently, the clot is left at rest for ripening for 610 hours. After the ripening time, before the start of bottling, kefir in the tank is mixed for 210 minutes and supplied to the packing machine M6OPZE for packing. It is recommended to keep packed kefir in the refrigerating chamber before implementation until it reaches the required value of conditional viscosity and temperature of 6 0С.

This line includes the following process equipment: Dairy tank B2OMG10

capacity 10 thousand liters each 2

Pump centrifugal NMU6 with a performance of 6 thousand l/hour 1

Pasteurization and cooling unit PLOP5

with a capacity of 5 thousand l/h 1

OPL - 5 consists of:

OMA3M milk cleaner with a capacity of 5 thousand l/h.. . 2

Two-stage homogenizer A1OGM with working pressure

up to 200 at a capacity of 5 thousand l/h 1

Tank G6OPB1000 for pasteurized milk

capacity 1 thousand liters 1

Balancing tank 1

The centrifugal pump for milk 36MTs1020Shch 1

Boiler 1

Hot water pump 3K9 1

Pump centrifugal 36MTs612 1

NRM2 dosing pump for starter supply

2502000 L/hr. 1

Starter mixer with ball valve 1

Double wall tank OTK-6 for milk fermentation

6 thousand liters each. 4

Packing and packing machine M6OPZE 1

This process line for the production of sour milk beverages by tank method is designed for a capacity of 12 tons per day.

Technical characteristics of the line

Capacity l/d - 12000

Two-shift operation mode

Pasteurization temperature, 0С 85-90

Homogenization pressure, 125-175

Fermentation temperature, 0S20-25

Cooling temperature of finished beverage, 0С 6

Drawings content

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