Milk is the food which exclusively sustains us during the first few months of life.
In addition to being a nutritious food for humans, milk provides a favorable environment for the growth of microorganisms. Yeasts, moulds and a broad spectrum of bacteria can grow in milk, particularly at temperatures above 16°C.
Microbes can enter milk via the cow, air, feedstuffs, milk handling equipment and the milker.
Raw milk :
The lacteal secretion , practically free from colostrum, obtained by the complete milking of one or more healthy cows(PMO).
BEST AND MOST COMPLETE OF ALL FOODS.
IT’S THE FIRST FOOD WE TASTE.
GOOD SOURCE OF PROTEINS, FATS, SUGARS, VITAMINES AND MINERALS.
CONTAINS ALL NUTRIENTS NECESSARY FOR GROWTH AND DEVELOPMENT.
Dairy Microbiology. Methods of preservation of milk and Milk ProductsSaugat Bhattacharjee
A vivid description of all the preservation methods of milk and milk products is present in the slides. Very useful for Microbiology, Dairy technology students.
Clean Milk Production Practices and its Management in India by Sunil Meenasunil meena
Milk is the main product from a dairy enterprise, produced basically as food for human consumption. A dairy farmer must, therefore, aim at maximising on milk output from his/her dairy herd. At the same time the farmer must ensure that milk is produced in clean and hygienic conditions so that it is fit for human consumption.
From public’s health point of view, milk is a very good media for bacterial and other micro-organisms development. As such, disease hazard in public can easily be predisposed by infected milk during production, handling and marketing.
Clean Milk Production Practices
Source Hygiene and Preparations
Check for mastitis with a strip cup or any other method.
Isolate sick animals and milk them last (Their milk should not be mixed with good milk).
Wash udder, teats and flank of the animal with clean water preferably add a disinfectant. Wipe with a clean cloth.
Always groom and cut the hair around the under.
Dispose fore-milk
Tie tails of troublesome animals when milking.
Milker’s Hygiene
Milker should: –
Be healthy and clean
Maintain short fingernails and hair cut (ladies can cover their heads when milking as guard to falling hair)
Avoid smoking during milking time.
Be quick and efficient
Milk continuously (no interruptions).
Milking Environment
The shed can be permanent or movable
Where possible provide a cement floor for easy and proper cleaning.
Water should drain easily and away from the shed
Provide a clean feed trough, water trough and protected store.
There should be a good source of water nearby
The shed should be located away from bad smells and odours
It should be cleaned after every milking
Livestock should not have access to the shed during the day
Utensils
a. Types
Use seamless utensils preferably aluminium or stainless steel
Use cans, sufurias or metal buckets in milking
Provide a good washing place
Washing procedure
Rinse excess milk with cold and clean water
Scrub with a brush using hot water mixed with a detergent e.g. soap or detergent
Rinse with cold water and place the utensils to dry on a rack upside down during the day.
c. Storage
Utensils should be stored at night in a safe and clean place, which is well ventilated.
Milking
a. Preparation
Do not excite the animals
Regularize milking intervals
b. Method
Squeeze the teat and do not pull.
All milk should be got from the under i.e. avoid incomplete milking
Use a teat dip after milking
Milk Handling
a. Filtering
Use a white filter cloth
Filter immediately after milking
Disinfect, wash and dry the filter cloth after use
b. Storage
Store milk in cool and clean place
The room used to store milk should without other materials such as chemicals and should also be lockable.
c. Marketing or Disposal
Milk should be delivered to the market as soon as possible
It is advisable to delivery milk early in the morning and evening to avoid hot periods of the day.
BEST AND MOST COMPLETE OF ALL FOODS.
IT’S THE FIRST FOOD WE TASTE.
GOOD SOURCE OF PROTEINS, FATS, SUGARS, VITAMINES AND MINERALS.
CONTAINS ALL NUTRIENTS NECESSARY FOR GROWTH AND DEVELOPMENT.
Dairy Microbiology. Methods of preservation of milk and Milk ProductsSaugat Bhattacharjee
A vivid description of all the preservation methods of milk and milk products is present in the slides. Very useful for Microbiology, Dairy technology students.
Clean Milk Production Practices and its Management in India by Sunil Meenasunil meena
Milk is the main product from a dairy enterprise, produced basically as food for human consumption. A dairy farmer must, therefore, aim at maximising on milk output from his/her dairy herd. At the same time the farmer must ensure that milk is produced in clean and hygienic conditions so that it is fit for human consumption.
From public’s health point of view, milk is a very good media for bacterial and other micro-organisms development. As such, disease hazard in public can easily be predisposed by infected milk during production, handling and marketing.
Clean Milk Production Practices
Source Hygiene and Preparations
Check for mastitis with a strip cup or any other method.
Isolate sick animals and milk them last (Their milk should not be mixed with good milk).
Wash udder, teats and flank of the animal with clean water preferably add a disinfectant. Wipe with a clean cloth.
Always groom and cut the hair around the under.
Dispose fore-milk
Tie tails of troublesome animals when milking.
Milker’s Hygiene
Milker should: –
Be healthy and clean
Maintain short fingernails and hair cut (ladies can cover their heads when milking as guard to falling hair)
Avoid smoking during milking time.
Be quick and efficient
Milk continuously (no interruptions).
Milking Environment
The shed can be permanent or movable
Where possible provide a cement floor for easy and proper cleaning.
Water should drain easily and away from the shed
Provide a clean feed trough, water trough and protected store.
There should be a good source of water nearby
The shed should be located away from bad smells and odours
It should be cleaned after every milking
Livestock should not have access to the shed during the day
Utensils
a. Types
Use seamless utensils preferably aluminium or stainless steel
Use cans, sufurias or metal buckets in milking
Provide a good washing place
Washing procedure
Rinse excess milk with cold and clean water
Scrub with a brush using hot water mixed with a detergent e.g. soap or detergent
Rinse with cold water and place the utensils to dry on a rack upside down during the day.
c. Storage
Utensils should be stored at night in a safe and clean place, which is well ventilated.
Milking
a. Preparation
Do not excite the animals
Regularize milking intervals
b. Method
Squeeze the teat and do not pull.
All milk should be got from the under i.e. avoid incomplete milking
Use a teat dip after milking
Milk Handling
a. Filtering
Use a white filter cloth
Filter immediately after milking
Disinfect, wash and dry the filter cloth after use
b. Storage
Store milk in cool and clean place
The room used to store milk should without other materials such as chemicals and should also be lockable.
c. Marketing or Disposal
Milk should be delivered to the market as soon as possible
It is advisable to delivery milk early in the morning and evening to avoid hot periods of the day.
The process of pasteurization was named after Louis Pasteur (1960S) who discovered that spoilage organisms could be inactivated in wine by applying heat at temperatures below its boiling point. The process was later applied to milk and remains the most important operation in the processing of milk.
Pasteurization made milk safer and the United State Food and drug Administration or FDA in the 1906-2006.
Dr. Purnedu Vasavada - Current and Emerging Organisms in Raw Milk that Affect...John Blue
Current and Emerging Organisms in Raw Milk that Affect Public Health - Dr. Purnedu Vasavada, University of Wisconsin-River Falls, from NIAA's One Health: Implications for Animal Agriculture, March 15 - 17, 2010, Kansas City, MO, USA.
Notes on the technology of milk powder and the faults that may occurs during storage. Besides, the manufacture of instant milk powder and how to modify cow milk to produce humanized milk.
The Milk Microbiology ppt is useful to the under graduate students. This ppt may help to summarize the studied content related to the mentioned points in the given collection of slides.
Food Technology Micro-organisms in Food ProductionMyt12
Power point aimed at students taking A2 Food Technology focusing on micro-organisms in food production - from healthy bacteria in yoghurt and cheese to food poisoning bacteria. A short focus on Mycoprotein is also included.
The process of pasteurization was named after Louis Pasteur (1960S) who discovered that spoilage organisms could be inactivated in wine by applying heat at temperatures below its boiling point. The process was later applied to milk and remains the most important operation in the processing of milk.
Pasteurization made milk safer and the United State Food and drug Administration or FDA in the 1906-2006.
Dr. Purnedu Vasavada - Current and Emerging Organisms in Raw Milk that Affect...John Blue
Current and Emerging Organisms in Raw Milk that Affect Public Health - Dr. Purnedu Vasavada, University of Wisconsin-River Falls, from NIAA's One Health: Implications for Animal Agriculture, March 15 - 17, 2010, Kansas City, MO, USA.
Notes on the technology of milk powder and the faults that may occurs during storage. Besides, the manufacture of instant milk powder and how to modify cow milk to produce humanized milk.
The Milk Microbiology ppt is useful to the under graduate students. This ppt may help to summarize the studied content related to the mentioned points in the given collection of slides.
Food Technology Micro-organisms in Food ProductionMyt12
Power point aimed at students taking A2 Food Technology focusing on micro-organisms in food production - from healthy bacteria in yoghurt and cheese to food poisoning bacteria. A short focus on Mycoprotein is also included.
Food processing, composition of milk, microorganism present, Different type of adulteration test (sugar, starch, Salt, urea), biochemical test (organoleptic, clot on boiling, alcohol, lactometer, fat determination, protein determination), different type of pasteurization, processing, spray drying, Standards of PFA, FSSAI, BIS (profile and regulations) & non food application of milk.
THIS presentation EXPLAINS biomedical waste management IN EASY WAY
Important links- NOTES- https://mynursingstudents.blogspot.com/
youtube channel
https://www.youtube.com/c/MYSTUDENTSU...
CHANEL PLAYLIST-
ANATOMY AND PHYSIOLOGY-https://www.youtube.com/playlist?list...
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FIRST AID- https://www.youtube.com/playlist?list...
HCM- https://www.youtube.com/playlist?list...
FUNDAMENTALS OF NURSING- https://www.youtube.com/playlist?list...
COMMUNICABLE DISEASES- https://www.youtube.com/playlist?list...
ENVIRONMENTAL HEALTH- https://www.youtube.com/playlist?list...
MSN- https://www.youtube.com/playlist?list...
HINDI ONLY- https://www.youtube.com/playlist?list...
ENGLISH ONLY- https://www.youtube.com/playlist?list...
facebook profile- https://www.facebook.com/suresh.kr.lrhs/
FACEBOOK PAGE- https://www.facebook.com/My-Student-S...
facebook group NURSING NOTES- https://www.facebook.com/groups/24139...
FOR MAKING EASY NOTES YOU CAN ALSO VISIT MY BLOG –
BLOGGER- https://mynursingstudents.blogspot.com/
Instagram- https://www.instagram.com/mystudentsu...
Twitter- https://twitter.com/student_system?s=08
#VITAMIN_A,#FUNCTIONS,#SOURCE, #DEFICIENCY,#DISEASE,#NIGHTBLINDNESS#XEROPHTHALMIA,#BITOTSPOT,#CORNEALXEROSIS, #CONJUNCIVALXEROSIS, YELLOWFRUITS,#MYSTUDENTSUPPORTSYSTEM, #rashes,#nursingclasses, #communityhealthnursing,#ANM, #GNM, #BSCNURING,#NURSINGSTUDENTS, #WHO,#NURSINGINSTITUTION,#COLLEGEOFNURSING,#nursingofficer,#COMMUNITYHEALTHOFFICER
The document briefs about the technique pasteurization. It is an important food preservation method. This is used in the food technology industry. The document details the major aspects of the technique.
Arithmetic mean of a series is obtained by dividing total of values in series by the number of items i.e.
Arithmetic mean is denoted by .
Determination of Arithmetic Mean for Ungrouped Data
Let be the “n” values of variable , then the arithmetic mean can be obtained by using the following formula:
Stem-and-Leaf
Stem-and-Leaf display is another graphical device that is useful for representing quantitative data sets. A stem-and-leaf display bears a strong resemblance to a histogram and serves the same purpose.
To construct a stem-and-leaf display we partition each measurement into two parts. The first part is called the stem, and the second part is called the leaf.
The stem consists of one or more of the initial digits of the measurement, and the leaf is composed of one or more of the remaining digits.
When leaves consist of more than one digit, all digits after the first may be rounded off. Decimals when present in the original data are omitted in the stem-and-leaf display.
The stems are separated from their leaves by a vertical line. Thus, we see that a stem-and-leaf display is also an ordered array of the data.
Types of Graphs
(i) Graph of time series or Historigram
(ii) Histogram
(iii) Frequency polygon
(iv) Frequency curve
(v) Cumulative Frequency polygon or Ogive
Historigram
A Historigram is constructed by taking time along X-axis and the value of the variable along Y-axis. Points are plotted and are then connected by straight line segments to get the Historigram.
Example: Suppose we walk in the nursery class of a school and we count the no. of books and copies that 45 students have in their bags. Suppose the no. of books and copies are
9, 9, 3, 5, 4, 7, 6, 7, 5, 6, 5, 5, 8, 7, 5, 5, 6, 6, 6, 9, 6, 7, 6, 6, 4, 5, 5, 6, 6, 6, 6, 7, 7, 6, 5, 4, 8, 7, 9, 9, 7, 8, 7, 7, 9.
Construct a discrete frequency distribution.
Visual representation of statistical data in the form of points, lines, areas, is known as graphical representation. Such visual representation can be divided in to two groups.
(i) Graph
(ii) Diagram
The basic difference between a graph and a diagram is that a graph is a representation of data by a continuous curve, while a diagram is any other one, two or three dimensional form of visual representation.
Taking of a measurement and the process of counting yield numbers that contain information. The objective of a person applying the tools of statistics to these numbers is to determine the nature of this information.
This task is made much easier if the numbers are organized and summarized.
Even quite small data sets are difficult to understand without some summarization. Statistical quantities such as the mean and variance can be extremely helpful in summarizing data but first we discuss tabular and graphical summaries.
There are several ways to present a statistical data like;
Frequency table
Simple bar diagrams
Multiple Bar Diagrams
Histogram
Frequency Polygon etc.
Steam and Leaf plots
Pie Charts
A frequency distribution is a tabular arrangement of data in which various items are arranged into classes or groups and the number of items falling in each class is stated.
The number of observations falling in a particular class is referred to as class frequency and is denoted by "f".
In frequency distribution all the values falling in a class are assumed to be equal to the midpoint of that class.
Data presented in the form of a frequency distribution is also called grouped data. A frequency distribution table contains a condensed summary of the original data.
There are two types of frequency distribution i) Simple Frequency distribution ) ii) Grouped Frequency distribution.
Statistics has been defined differently by different authors from time to time. Generally it is considered to be the subject that deals with percentage, charts and tables.
The word statistics comes from the Latin word status, meaning a political state originally meant information useful to the state e.g. information about the size of populations and armed forces.
The word statistics is defined as a discipline that includes procedure and techniques used to
Collect
Process
Analyze numerical data to make inference and to reach decision in the face of uncertainty.
Introduction:
Mercury is the most hazardous metal for human health and environment.
It has high toxicity, volatility.
It has the tendency to bio-accumulate in human body.
Mercury is on the priority list of 129 chemical substances that harms the living organisms.
A GIS is a particular form of Information System applied to geographical data.
An Information System is a set of processes, executed on raw data to produce information which will be useful when making decisions.
GIS is not only a tool for making maps, it is a system for data analysis.
Industrial microbiology is a branch of applied microbiology in which microorganisms are used in industrial processes.
Example: In the production of high-value products such as drugs, chemicals, fuels and electricity.
Microbes are the mini chemical factory
Possess a broad variety of enzymes
High metabolic activity. So, it can grow and multiply rapidly
Possess a large surface area for the quick absorption of nutrients
Grow on inexpensive substrate
Xenobiotics:
The word xenobiotic is derived from Greek word xenos mean foreigner or stranger.
Xenobiotics are man made chemicals that are foreign in nature.
Xenobiotics can not be produced naturally.
Thermodynamically stable in environment.
Produce adverse effects in human:
Cell injury
Toxicity
Cancer
Physiological and immunological effects.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
2. TABLE OF CONTENTS
Introduction……………………………………
Composition of milk…………………………..
Physical properties
pasteurization of milk…………………………
Sterilization of milk…………………………..
Milk products…………………………………
References…………………………………….
3. INTRODUCTION
Milk is the food which exclusively sustains us during the first few months of life.
In addition to being a nutritious food for humans, milk provides a favorable
environment for the growth of microorganisms. Yeasts, moulds and a broad spectrum of
bacteria can grow in milk, particularly at temperatures above 16°C.
Microbes can enter milk via the cow, air, feedstuffs, milk handling equipment and the
milker.
Raw milk :
The lacteal secretion , practically free from colostrum, obtained by the complete milking
of one or more healthy cows(PMO).
4. Water : 87-88% .
Carbohydrate: (approx. 5%)
• Mainly lactose→ lactic acid by bacterial fermentation.
• In heated milk products, e.g., in condensed milk, there is also lactulose which is a little sweeter.
Fat: 3-4% in whole milk.
•contains fat soluble vitamins, pigment carotene & Xanthophylls; contains cholesterol &
phospholipids but is primarily TGs(95%) .
• The fat in milk occurs in the form of droplets or globules, surrounded by a membrane
and emulsified in the milk serum part.
COMPOSITION OF MILK
5. COMPOSITION OF MILK
Protein: (3-4%).
Casein (80% of milk protein):
The casein is arranged in super-structures called micelles, which consist of
protein together with phosphate, citrate and calcium.
The caseins are actually a group of similar proteins, which can be separated
from the other milk proteins by acidification to a pH of 4.6 .
The casein micelles also may be coagulated by addition of the enzyme
rennin.
6. COMPOSITION OF MILK
Vitamins & Minerals:
Vitamins A, B6, B12, C, D, K, E, thiamine, niacin, biotin, riboflavin.
Vitamin A is naturally in the fat component of whole milk.
whole milk is generally (98%) fortified with vitamin D because it is naturally present only
in small amounts.
Minerals:
Ca & P approx. 1% of milk
Ca is present as calcium caseinate, calcium phosphate & calcium citrate.
Other minerals present are chloride, magnesium, potassium, sodium, and sulfur.
7. CONTAMINATION OF MILK AND
MILK PRODUCTS
Milk is sterile at secretion in the udder but is
contaminated by bacteria even before it leaves the
udder.
Further infection of the milk by microorganisms
can take place during milking, handling, storage, and
other pre- processing activities.
9. PHYSICAL PROPERTIES
Acidity: fresh milk pH is 6.5-6.7 at 25°C.
Viscosity: depends on the amount of fat, size of fat
globules & extent of clustering of globules
Freezing point: -0.55°C addition of 1% of water to milk
↓ FP by -0.0055°C.
Boiling point: 100.2°C.
10. Pasteurized milk is raw milk that has been heated to a
specified temperature and time to kill pathogens that may be
found in the raw milk.
Pasteurized milk can store for short time.
Only eliminate pathogenic micro-organisms.
For pasteurization only heat is used.
PASTEURIZATION OF MILK
11. PATHOGENS
A pathogen or infectious agent is a biological agent that
causes disease or illness to its host. The term is most often
used for agents that disrupt the normal physiology of a
multicellular animal.
A bacterium, virus, or other microorganism that can
cause disease.
12. HISTORY OF PASTEURIZATION
Pasteurization term is first time used by Louis
Pasteur in 20 April 1862,and eliminate bacteria
in wines
The pasteurization of milk was adopted in
1895.
13. PASTEURIZATION OF MILK
Methods:
1. High-Temperature Short Time (HTST)
Pasteurization
2. Low-Temperature Long Time (LTLT)
pasteurization
3. Ultra High Temperature (UHT) Pasteurization
14. (1) HIGH-TEMPERATURE SHORT
TIME (HTST) PASTEURIZATION
This type of pasteurization is also known as flash
pasteurization.
High temperature short time. This method is know as
continuous process of pasteurization and is 72C for 15 sec .
This will ensure that the milk is heated uniformly to the
required temperature.
15. HIGH-TEMPERATURE SHORT
TIME (HTST) PASTEURIZATION
This method is most suitable in continuous pasteurization
systems.
Flash pasteurized milk will keep for between 16 and 21
days. For commercial reasons, some manufacturers
intentionally reduce the number of days to push the products
out of the shelves.
16. (2) LOW-TEMPERATURE LONG
TIME (LTLT)
Low temperature long time this method commonly know as
Batch or Holding method of pasteurization and ideal
temperature is 63C for 30 minute(Milk)
This method is best for batch pasteurization where the milk
is held in a jacketed vat for effective pasteurization.
There are many designs of batch pasteurizers in the market
that are suitable for both domestic and commercial use.
17. (3) ULTRA HIGH TEMPERATURE
(UHT) PASTEURIZATION
This process was developed in 1950.and temperature
are provide 135C to 150 C for one second.
Despite the risk of Millard browning, UHT
pasteurization remains the most popular milk
preservation method for safe and stable milk.
20. PURPOSE OF PASTEURIZATION
To increase milk safety for the consumer by destroying
disease causing microorganisms (pathogens) that may be
present in milk.
To increase keeping the quality of milk products.
To reduce the bacterial population in milk.
21. STERILIZATION OF MILK
Sterilization is a process of killing all microorganisms in Milk.
Commercially sterilized milk:
It is cooked to an even higher temperature for a shorter
amount of time.
Commercially sterile milk can safely remain on the shelf
for months, and does not need to be refrigerated until
opened. e.g ultra pasteurized milk.
22. STERILIZATION OF MILK
Virtually sterile:
Milk is virtually sterile when it is synthesized in a healthy cow's
udder (mammary gland). Many of these bacteria are not harmful to
humans, but some may be harmful to humans even though the
cows are not affected and appear healthy.
Milk may become contaminated with bacteria during or after
milking.
23. STERILIZATION PROCESS
The sterilization process in the canned product can be subdivided
into three phases:
Phase 1 :(heating phase) the product temperature is increased
from ambient to the required sterilization temperature.
Phase 2 :(holding phase) This temperature is maintained for a
defined time.
Phase 3 :(cooling phase) the temperature in the can is decreased
by introduction of cold water.
25. Sunlight
Drying
Heat:
Dry heat:
flaming, incineration, hot air .
Moist heat:
pasteurization, boiling, steam under
pressure.
Filtration:
candles, asbestos pads,
membranes.
Radiation
Ultrasonic and sonic
vibrations.
PHYSICAL METHOD OF STERILIZATION
These are physical agents which are used for sterilization:
26. Alcohol
Ethyl, isopropyl,
Aldehydes
Formaldehyde, glutaraldehyde
Dyes
Halogens
Phenols
Gases:
Ethylene oxide, formaldehyde,
beta propiolactone.
CHEMICAL METHOD OF
STERILIZATION
These are chemical agents which are used for sterilization:
27. GENERALLY USED STERILIZATION
METHODS IN LABORATORY
Dry heat :
Glassware and plastic ware (empty vessels), and instruments
may be sterilized by dry heat in an oven at 160-180 C for 3 hr.
But most people prefer to autoclave.
More recently, glass bead sterilizers are being employed for
the sterilization of forceps, scalpels, etc.; These devices use dry
heat.
28. GENERALLY USED STERILIZATION
METHODS IN LABORATORY
Flame sterilization :
Instruments like forceps, scalpels, needles, etc.
Are ordinarily flame sterilized by dipping them in
95% alcohol followed by flaming.
These instruments are repeatedly sterilized during
the operation to avoid contamination.
29. GENERALLY USED STERILIZATION
METHODS IN LABORATORY
Autoclaving :
Like as Culture vessels are generally sterilized by heating in
an autoclave or a pressure cooker to 121C at 15P for 15 to 40
minutes.
Sterilization during autoclaving depends mainly on
temperature.
Certain types of plasticware and some instrument, e.g,
Micropipettes, etc., Are also autoclavable.
30. ADVANTAGES OF STERILIZATION
No significance rise in temperature.
Continuous process due to short exposure time.
Distinction rich flavor.
Economical to use.
Easy control of lethality of various materials and
supplies.
31. DISADVANTAGE OF STERILIZATION
Increased cost of production.
May lead to color change.
Sterilization depreciates milk’s nutritional value.
Packaging of UHT milk is non-biodegradable.
UHT process alters milk’s original flavor.
32. Products have shorter
shelf life.
Discovered by Louis
Pasteur.
Eliminate only pathogenic
bacteria.
Products have longer shelf
life.
Discovered by Nicolas
Appert
Eliminate All form of micro
organisms.
DIFFERENCE
Pasteurization: Sterilization:
33. NON-FERMENTED PRODUCTS
Skim milk:
When all the milk fat is removed from
whole milk. Extensive use in bakery &
confectionery. Also used for low calorie diets &
children who need high protein.
Evaporated milk:
Made up of cow’s milk & has thick creamy
appearance.Un sweetened condensed milk ,cow
milk product where about 60% of water
removed from fresh milk.
34. NON-FERMENTED PRODUCTS
Sweetened condensed milk:
It is made by removing most
of water from cow’s milk . It
is sweeter have high calories
then evaporated milk.
35. A LACTOSE-FREE MILK:
It is available for people who are
lactose-intolerant. This modified milk
is made by filtering regular milk to
remove half the lactose. The enzmye
lactase is then added to the milk to
break down the remaining lactose into
simpler forms which the body can
absorb.
NON-FERMENTED PRODUCTS
36. NON-FERMENTED PRODUCTS
Malted Milk : is a powdered gruel made from a mixture of malted
barley, wheat flour, and whole milk, which is evaporated until it forms a
powder.
Malt powder comes in two forms:
Diastatic malt contains enzymes that break down starch into
sugar; this is the form bakers add to bread dough to help the
dough rise and create a good crust.
Nondiastatic malt has no active enzymes and is used
primarily for flavor, mostly in beverages. It sometimes
contains sugar, coloring agents, and other additives.
37. Rabri: concentrated sweetened product
comprising several layers of clotted cream.
Sugar is added to milk reduced to 1/3 of its
original volume.
Ice-cream: frozen dairy product
consisting of whole milk, skim milk, cream,
butter, condensed milk products or dried milk
products.
NON-FERMENTED PRODUCTS
38. CREAM:
Cream is the high-fat component separated
from whole milk as a result of the creaming
process. It has a higher proportion of fat
droplets to milk than regular fluid milk; and
according to federal standards of identity,
cream must contain 18% milk fat or more.
Due to this high fat content of cream
compared to milk, some yellow, fat- soluble
pigments may be apparent.
NON-FERMENTED PRODUCTS
39. FERMENTED MILK PRODUCTS
Butter:
It id dairy product made fromm the fat & protien components of
milk or cream.
fat content is generally about 80%.
Made from sweet or sour cream.
Butter may have a yellow color due to the fat-soluble animal
pigment, carotene, or an additive.
40. Ghee: a type of clarified butter, is prepared by
simmering butter and removing the residue.
The texture, colour, and taste of ghee depend on
the quality of the butter and the duration of the
boiling.
Buttermilk: was the liquid left behind after
churning butter out of cream. It is beneficial to
health as it contains probiotic microbes.
FERMENTED MILK PRODUCTS
41. FERMENTED MILK PRODUCTS
Yogurt is a variety of curd. Whole, low fat, skim milks & even
cream can be used to make yogurt.
In production of yogurt, a mixed culture of streptococcus
thermophilus, lactobacillus acidophilus is usually added to to the
pasteurised milk & incubated.
Increase in folic acid concentration during
fermentation.
42. FERMENTED MILK PRODUCTS
Fermented milk is useful for a wide variety of
disorders like colitis, constipation, diarrhoea,
gastroenteritis, diabetes & hyper cholesteremia.
Shrikhand: fermented product made by
concentrating dahi by removing whey & to which
sugar,
flavor & condiments are added.
43. Flavour
Texture
Type of milk
Type of bacteria & mould
species used in ripening,
Salts & seasoning added
Manufacturing & processing
method..
FERMENTED MILK PRODUCTS
Cheese is made up of casein. Varieties of cheese are differentiated
according to their :
44. REFERENCES
Srilaksmi.B, Food Science, Third Edition, 2003, New Age
International Publisher, New Delhi.
Vaclavik,V.A., Christian,E.W., Essentials of Food Science,
Third Edition, Springer.
Journal of food science & technology.
http://www.ifst.org/learninghome/.