Food Production - Biotechnology - Yoghurt Production - GCSE Biology (9-1)

Summary

This script delves into the role of microorganisms in food production, specifically biotechnology. It highlights two key examples: yeast in bread making and bacteria in yogurt production. The process of making yogurt involves sterilization, pasteurization of milk, and fermentation using lactobacillus bacteria. These bacteria convert lactose to lactic acid, creating the yogurt's sour taste and solid texture. The final product can be flavored and cooled to yield a tangy, live bacteria-rich yogurt.

Takeaways

• 🔬 Microorganisms are tiny life forms that can be seen only with a microscope and can have both harmful and beneficial roles.
• 🍞 In food production, microorganisms are used in biotechnology, such as yeast in bread making and bacteria in yogurt production.
• 🥛 The yogurt-making process involves adding a specific bacteria, lactobacillus, to milk to ferment the lactose sugar into lactic acid, giving yogurt its sour taste.
• 🔥 Sterilization of equipment is crucial in yogurt production to prevent unwanted bacteria growth and ensure the safety of the final product.
• 🌡️ Pasteurization of milk is done at 72 degrees Celsius for 15 seconds to kill any existing bacteria, ensuring only the desired lactobacillus is present.
• 🌡️ After adding lactobacillus, the milk is incubated at a temperature between 37 and 44 degrees Celsius for 3 to 6 hours to allow fermentation.
• 🍯 Lactic acid produced during fermentation lowers the pH, causing the milk to solidify and form yogurt.
• 🍓 Once the yogurt is cooled, it becomes a thick product with live bacteria and a tangy taste, which can be enhanced with fruits or flavors.
• 🧊 Cooling the yogurt after fermentation is essential to stop the bacterial activity and achieve the desired consistency and flavor.
• 🧑‍🔬 The entire process of yogurt production is a careful balance of microbiology and temperature control to create a safe and tasty product.

Q & A

What are microorganisms and why are they important in food production?

Microorganisms are tiny life forms that can only be seen with a microscope. They are important in food production because they can be harnessed for beneficial uses, such as in biotechnology.

How do microorganisms cause disease in humans?

Some microorganisms can cause serious diseases in humans by infecting the body and disrupting normal bodily functions.

What is biotechnology in the context of food production?

Biotechnology in food production refers to the use of microorganisms to create or modify food products, such as using yeast to make bread or bacteria to produce yogurt.

What is the role of yeast in bread making?

Yeast plays a crucial role in bread making by fermenting sugars in the dough, producing carbon dioxide gas which causes the dough to rise and gives bread its texture.

Which bacteria is used in yogurt production and what is its function?

Lactobacillus is the bacteria used in yogurt production. It ferments lactose in milk, producing lactic acid which gives yogurt its sour taste and causes the milk to solidify.

What is the process of sterilization in yogurt production and why is it necessary?

Sterilization in yogurt production involves cleaning equipment with bleach or steam to kill any unwanted bacteria. This is necessary to prevent contamination and ensure that only the desired bacteria, like Lactobacillus, are present.

What is pasteurization and how does it relate to yogurt production?

Pasteurization is the process of heating milk to 72 degrees Celsius for 15 seconds and then cooling it rapidly. It is used in yogurt production to kill any existing bacteria in the milk, ensuring that only the added Lactobacillus bacteria will grow.

What happens during the incubation stage of yogurt production?

During the incubation stage, pasteurized milk is mixed with Lactobacillus bacteria and kept at a temperature between 37 and 44 degrees Celsius for 3 to 6 hours. This allows fermentation to occur, converting lactose to lactic acid and causing the milk to solidify.

Why does the pH of milk drop during yogurt production?

The pH of milk drops during yogurt production due to the production of lactic acid by Lactobacillus bacteria as they ferment lactose. This acidification contributes to the sour taste and texture of yogurt.

How does cooling affect the final yogurt product?

Cooling the yogurt after fermentation slows down or stops the bacterial activity, solidifying the yogurt and giving it a thick consistency. It also helps to preserve the yogurt by inhibiting bacterial growth.

Can yogurt be flavored after production and what are some common additions?

Yes, yogurt can be flavored after production. Common additions include fruits, sweeteners, and various flavorings to enhance taste and provide variety to the yogurt product.

Outlines

00:00

🌡️ Yogurt Production with Lactobacillus

This paragraph delves into the role of microorganisms in food production, specifically focusing on the use of bacteria in yogurt making. It explains that microorganisms, visible only under a microscope, can either cause diseases or be beneficial for us. The process of biotechnology in food production is exemplified by the use of yeast in bread and bacteria in yogurt. The script describes the yogurt production process in detail, starting with sterilization of equipment to prevent unwanted bacteria growth. Milk is then pasteurized at 72 degrees Celsius for 15 seconds and cooled rapidly to kill any existing bacteria. Lactobacillus bacteria are added to the milk, and the mixture is incubated at 37 to 44 degrees Celsius for 3 to 6 hours, allowing fermentation to occur. During this time, the bacteria convert lactose into lactic acid, which lowers the pH and causes the milk to solidify into yogurt. The final product is a thick yogurt with live bacteria and a tangy taste from the lactic acid, which can be flavored with fruits or other additives.

Keywords

💡Microorganisms

Microorganisms are tiny living things that can only be seen with a microscope. In the context of the video, they play a crucial role in food production, particularly in the making of bread and yogurt. They can be both harmful, causing diseases, or beneficial when used in biotechnology.

💡Biotechnology

Biotechnology is the use of living organisms or their components to make products. In the video, it is specifically applied to food production, where microorganisms are harnessed to create products like bread and yogurt. This process involves the controlled use of microorganisms for human benefit.

💡Yeast

Yeast is a type of microorganism used in the production of bread. It ferments the sugars in the dough, producing carbon dioxide which causes the bread to rise. The video uses yeast as an example of how microorganisms can be beneficial in food production.

💡Lactobacillus

Lactobacillus is a type of bacteria used in the production of yogurt. It ferments lactose in milk to produce lactic acid, which gives yogurt its characteristic sour taste and thick consistency. The video explains the process of adding Lactobacillus to milk to create yogurt.

💡Fermentation

Fermentation is a process where microorganisms convert carbohydrates into acids, gases, or alcohol. In the video, fermentation is used by Lactobacillus to convert lactose in milk into lactic acid, which is essential for yogurt production.

💡Pasteurization

Pasteurization is a process of heating milk to a specific temperature (72 degrees Celsius for 15 seconds in the video) and then cooling it rapidly. This process kills bacteria in the milk, ensuring that only the desired bacteria, like Lactobacillus, are present for yogurt production.

💡Sterilization

Sterilization is the process of killing or removing all forms of life, including bacteria, viruses, and fungi, from equipment. In the video, sterilization of equipment is emphasized to prevent unwanted bacteria from contaminating the yogurt-making process.

💡Lactic Acid

Lactic acid is a product of fermentation by microorganisms like Lactobacillus. In the video, it is mentioned as the waste product of fermentation that gives yogurt its sour taste and helps in coagulating the milk to form yogurt.

💡pH

pH is a measure of acidity or alkalinity of a solution. In the context of the video, the pH of milk drops due to the production of lactic acid by Lactobacillus during fermentation, which is what causes the milk to solidify and form yogurt.

💡Incubation

Incubation in the context of the video refers to the process of maintaining a controlled temperature (between 37 and 44 degrees Celsius) for a specific period (3 to 6 hours) to allow the bacteria to ferment the milk and produce yogurt.

💡Probiotics

Probiotics are live beneficial bacteria, like Lactobacillus, that are often found in yogurt. The video mentions that yogurt contains live bacteria, which are probiotics that can provide health benefits when consumed.

Highlights

Microorganisms play a crucial role in food production through biotechnology.

Yeast is used in bread making, while bacteria are used to produce yogurt.

Lactobacillus bacteria ferment lactose in milk to produce lactic acid, giving yogurt its sour taste.

Sterilization of equipment is essential before yogurt production to prevent contamination.

Pasteurization of milk kills unwanted bacteria, ensuring only desired lactobacillus is present.

Incubation of pasteurized milk with lactobacillus at 37-44°C for 3-6 hours initiates fermentation.

Fermentation converts lactose to lactic acid, lowering the pH and solidifying the milk into yogurt.

Cooling the fermented milk results in a thick yogurt with live bacteria and a tangy taste.

Yogurt production involves a series of precise steps, including sterilization, pasteurization, fermentation, and cooling.

The use of microorganisms in food production is a form of biotechnology that has practical applications.

Lactobacillus is a key bacteria in yogurt production, responsible for the fermentation process.

The fermentation process is critical for the development of yogurt's texture and flavor.

Proper temperature control during incubation is essential for effective yogurt production.

The pH drop due to lactic acid production is what causes milk to solidify into yogurt.

Yogurt can be flavored with fruits or other additives to create a final product with a desired taste.

The process of yogurt production showcases the harnessing of microorganisms for human benefit.

Biotechnology in food production can lead to innovative and healthful food products like yogurt.

Transcripts

[Music]

let's now talk about micron isms and

their role in food production micro isms

are liberalism's that can only be seen

with the help of a microscope they can

cause serious disease in humans or they

can be harnessed and used for our

benefit micro isms can be used in food

production we call this process

biotechnology there are two examples you

need to know about in real detail one is

how yeast is used to make bread and the

other one is how bacteria are used to

produce yogurt basically idea behind

making yogurt is that you add a bacteria

called lactobacillus to milk they use

this lactose sugar in the milk for

fermentation they produce lactic acid as

a waste product which is what gives the

yogurt its sour taste so let's go

through the main stages of yogurt

production first you've got

sterilization it's very important that

you sterilize all your equipment you're

going to use to make yogurt with bleach

or steam because the last thing you want

to do is breed unwanted harmful bacteria

so you make sure everything is sterile

first you didn't want to pasteurized

some milk this heats milk up to 72

degrees 15 seconds and it cools it

rapidly down that's what pasteurization

is and the reason you do that is to also

kill any bacteria in the milk we don't

any bacteria in there the only bacteria

than what we want are the ones that we

then add which other lactobacillus so we

add those in now we incubate this

pasteurized milk with the bacteria

between 37 and 44 degrees C for about 3

to 6 hours during this process the

fermentation will occur the bacterial

convert the lactose to lactic acid the

pH drops because of the lactic acid

being formed and this makes the milk

then goes solid and that's how you get

that the solid formed yogurt when you

then cool it all down you get a nice

thick yogurt product do with live

bacteria in it usually and that kind of

slightly tangy taste from the lactic

acid you can add fruits or flavors and

outpoint to get your final yogurt

product

you