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Pickle Potted and Preserved
Transcript of Pickle Potted and Preserved
Food Technology Assignment
1. Devondale Long Life Milk - UHT (Ultra High Temperature)
Part B - Pasteurisation
Thankyou for watching!
UHT is a preservation technique that stands for Ultra High Temperature, this process involves the object for example mainly milk, to be heated at high temperature of around 135 degrees for one or two seconds. The short flash of extreme heat kills all the bacterial spore. UHT is used for many products such as fruit juices, dairy products and more.
Freeze Drying is the process of vacuuming all the moist and liquid to prevent or delay bacteria growth. This process prevents food spoilage as the lack of moisture prevents bacterial growth whilst on the otherside it also makes the product alot lighter!
2. Nescafe Gold - Freeze Drying
Canning is the simple process of storing food where it is air tight. The food canned is usually sterile (bacteria-free from freezing, heating, pastuerisation, dehydration or chemical activity), which makes it have a longer lasting life.
Until you open the can ofcourse, the bacteria will start attacking the food until it is then stored in the fridge, which will only just delay the bacteria's growth.
3. Val Verde Diced Tomatoes - Canning
Dehydration is the food preservation method that involves the removal of water and moisture from the food, which can stop or impede the growth of microorganisms.
4. Angus Park Sultanas - Dehydration
8. Primo Premium Bacon Rashers-Salting
6. Dairy Farmer's Fresh Milk - Pasteurization
5. McCains Pea - Freezing
(cc) image by nuonsolarteam on Flickr
Refrigeration is a very common technique used to preserve food of many types whether it be liquids, solids, seafood and more.
It involves putting the substance/food into low temperature which can either kill off the bacteria or just slow it down by a lot.
Pickle, Potted and Preserved
Freeze Drying also involves the phase of 'Sublimation', where the solid instantly turns into the state of 'gas' without becoming a liquid.
7. Continental Cream of Mushroom Cup-a-Soup
Pasteurization is the heating process of heating food, usually in the form of liquid.
Pasteurization aims to destroy most harmful bacterias and deplete majority of the harmful microorganisms, though not all bacteria like UHT and sterilization.
Pasteurization is done by heating the food in high temperatures around 71degrees around 15-20seconds.
The bacteria is destroyed from the flash of strong heat which is then followed by the quick change of temperature, which is usually cold.
The procedures start with freezing the food, once frozen the product is placed under a vacuum and turns into gas (in other words sublimes).
The vacuumed liquids in the chamber soon condenses and once again becomes a solid.
A traditional method to drying/dehydration is by hanging it out amidst the open air in the sun, salting it or smoking it. Though now in our modern society, technology such as an 'electrical food dehydrator', which is faster and more effective.
This product also involves the preservation method of "Dehydration".
Frozen peas are usually blanched (boiled to kill the bacteria but then cooled down after to stop the cooking).
By freezing all the taste, textures, appearance, colour and qualities are kept after simmering or boiling the peas once again. By freezing this lets no bacteria start their growth or delay it, as said before it is boiled before packaged to be frozen, which shows the peas have no bacteria and is frozen to keep the temperature where no bacteria can reproduce or begin a 'colony'.
Freezing lets the food product (in this case McCain's Peas) to "freeze in time", so in other words it will be preserved to the state of peas that were freshly picked.
Salt itself, is a natural preservative that can draw out the moisture and liquid present in most foods, as well as the micro-organisms.
Salting is commonly used for meat products.
Salting reduces the moisture so it can avoid spoilage since bacteria can grow though moisture, hence why salt is usually used for things with moisture such as meat.
Pasteurization as said before is the process of heating food products, usually liquids such as milk in high temperatures around 71 degrees for 15-20seconds.
It plans to kill the harmful micro-organisms.
1 ) The Process of Pasteurization
Usually fruits and vegetables are preserved using this method
A benefit of Dehydration is that it reduces weight and size of the food product!
Step 3 :
2. 5 Foods preserved by Pasteurization
Step 1 :
(cc) image by nuonsolarteam on Flickr
It involves the reduction of moisture, thus impeding the growth of bacteria.
Other than the natural sun drying, they can reduce the moisture content more through the electrical 'driers'.
It is then concealed in an airtight container.
To keep the preservation before it gets bought, it's usually kept in a cool place with an airtight bag.
After the process it's usually kept in an airtight plastic or glass bottle, in a cold place such as a fridge
They are then sealed in a bag also in anywhere cold such as the fridge or freezer if it isn't going to be used for a long time.
The first step in pasteurization would be to obviously get the product, in this case it would be milk.
Secondly there are two ways to continue firstly is to pour the raw milk into a stainless steel pot (most farms or residents would use this method).
OR like most factories or huge properties would do, is pour it into their machines that usually can hold large volumes of liquid.
The temperature is then heated up to around 71degrees and left to boil for 15-20 seconds.
It then passes through to a cooling area
Lastly after the milk/ other liquids have cooled down, the milk then flows into another machine where it gets packaged into a sterilized container
1. Most dairy products such as milk, yoghurt and butter
2. Juices (Orange Juice, Cranberry Juice etc)
3. Canned Foods
5. Non-carbonated Drinks
3. How does pasteurization prevent spoilage?
5. Are there any advances in Pasteurization?
4. Food storage for pasteurized foods
(cc) photo by medhead on Flickr
Pasteurization kills all the harmful bacteria present to avoid diseases caused by bacteria such as typhoid fever, yimnesia (the bacteria that mainly invades raw milk) and more.
After pasteurization the liquid is poured into an airtight jar/container, it is then placed in an cold area such as the fridge to delay the expiration date/prolong the shelf life.
It ensures longer shelf life/expiry dates, a safer product to drink whilst keeping the qualities.
Less bacteria safer to eat and it also delays bacterial growth!
The high temperatures kill most of the undesired bacteria as bacteria has certain temperature zones which are usually lower than the temperature pasteurization uses (71 degrees).
While the high temperature might kill the microbes that cause spoilage, it won't last forever until they invade once again.
Though it's in the fridge, by the third week it would start to lose it's quality and textures.
Pasteurization officially began in 1862, where 'Louis Pasteur' investigated the theory of germs and experimented how to keep milk and other beverages from going sour.
From boiling in a pot, to factories producing and boiling large volumes of pasteurized milk there aren't much big advances since the 20th century.
From 1891 where the milk factories were made, the only things that improve were the quantity and qualities of the machine that produce and pasteurize the milk.
The milk pasteurization process is kept unchange but with just different models and machines, though overall over the last few decades packaging (such as from milk containers to plastic containers), technology and pasteurization research and methods are thought out and minimally improved.