Degreening

Summary

The video script discusses 'The Greening' process in agricultural commodities, specifically for citrus fruits like oranges. It involves removing the green pigmentation or chlorophyll from the fruit peel to make it visually appealing to consumers. Ethylene gas or temperature treatments are used to expedite this process, which is suitable only for mature fruits that won't continue to ripen post-harvest due to their non-climatic nature. The script outlines the steps for an effective degreening process, including ensuring fruit maturity, applying fungicides, maintaining ethylene levels, monitoring carbon dioxide, and maintaining high humidity. It clarifies that degreening does not improve fruit quality and distinguishes between ethylene gas and calcium carbide, the latter being an artificial ripening agent.

Takeaways

• 🟢 The 'Greening' process refers to the removal of green pigmentation or chlorophyll from certain fruits, especially citrus fruits like oranges, to improve their visual appeal to consumers.
• 🍊 Ethylene gas or temperature treatments are commonly used to accelerate the 'Greening' process, which is applicable to mature fruits only.
• 🚫 Immature fruits are not suitable for 'Greening' due to their high acid and low sugar levels, which do not meet quality standards.
• 🌡 Citrus fruits are non-climatic, meaning they do not continue to ripen after harvest, unlike tomatoes, peaches, or pineapples.
• 🌳 Chlorophyll, the green pigment in plants, is responsible for the green color in citrus fruits, and its degradation by ethylene is a natural process.
• 🍂 The natural 'Greening' of citrus peel occurs when night temperatures are cooler in late autumn, but may not happen if the weather is too warm.
• 🍋 Mature Valencia oranges can 'regreen' in summer heat after a natural color has begun, highlighting the influence of temperature on the 'Greening' process.
• 📏 To ensure the best outcome during 'Greening', it's important to check that the fruit is mature with more than 50% color development.
• 💧 Fruit with dark green blood shells may not color well after harvest, indicating the importance of selecting appropriate fruits for the process.
• 🍇 After applying an initial fungicide to prevent post-harvest treatments, it's crucial to let the fruit dry before loading it into the 'Greening' room.
• 🌡️ The 'Greening' room should maintain a controlled temperature of 20 to 25°C up to 29°C, which is suitable for fruit from humid subtropical regions.
• 💨 High humidity levels (around 95% relative humidity) are necessary during 'Greening' to prevent excessive fruit weight loss.

Q & A

What does 'The Greening' refer to in the context of AB materials and agricultural commodities?

The Greening refers to the process applied to certain fruits, particularly citrus fruits like oranges, where green pigmentation or chlorophyll is removed from the fruit peel to make it more visually appealing to consumers.

What methods are typically used to accelerate the de-greening process of citrus fruits?

The de-greening process typically uses ethylene gas or temperature treatments to speed up the removal of green pigmentation from the fruit peel.

Why is only mature fruit suitable for de-greening?

Only mature fruit is suitable for de-greening because immature fruit has very high acid levels and low sugar levels, which do not meet the standard. Additionally, citrus fruit is non-climatic, meaning it will not continue to ripen after harvest.

What is the role of chlorophyll in citrus fruits and how does it relate to the de-greening process?

Chlorophyll is the green pigment in plants and is responsible for the green color in citrus fruits. The de-greening of the skin is a natural process of chlorophyll degradation by ethylene on the tree.

How does the natural de-greening process occur in citrus fruits on the tree?

The natural de-greening of the peel happens when night temperatures are cooler in late autumn. Even though the fruit may be mature inside and ready to eat, the weather may be too warm for natural color development.

Can mature Valencia oranges regreen during summer due to heat?

Yes, a similar process in reverse can happen with mature Valencia oranges in summer where the fruit can regreen due to heat after a natural color has begun.

What are the criteria for fruit to be de-greened in the packing shell according to Australian Citrus standards?

Only fruit that meets Australian Citrus standards (ACS) should be de-greened in the packing shell.

What are some considerations to ensure the best outcome during the de-greening process?

To ensure the best outcome, it's important to ensure the fruit is mature with more than 50% color development, branch the fruit with an initial fungicide to prevent post-harvest rot, let the fruit dry before loading it into the de-greening room, and maintain controlled doses of ethylene and suitable temperature and humidity levels.

Why is it important to monitor carbon dioxide levels in the de-greening room?

It is important to monitor carbon dioxide levels because harvested fruit is still respiring and releasing carbon dioxide into the room. High levels of carbon dioxide can inhibit the de-greening process and also reach unsafe levels for people entering the room.

What is the recommended humidity level in the de-greening room and why is it important?

The recommended humidity level in the de-greening room should be around 95% relative humidity. Maintaining high humidity levels is important to prevent excessive fruit weight loss during the de-greening process.

Does the de-greening process improve the eating quality of the fruit?

No, the de-greening process does not improve the eating quality of the fruit. It is a visual enhancement and does not affect the taste or nutritional value.

How does the use of ethylene gas in de-greening differ from calcium carbide or curu?

Calcium carbide or curu reacts with moisture to produce acetylene gas, which mimics the action of ethylene and is used as an artificial ripening agent. However, acetylene is not as effective as ethylene, and a much larger quantity must be used for the same effectiveness.

Outlines

00:00

🍊 The Process of 'Greening' in Citrus Fruits

This paragraph introduces the concept of 'Greening' in agricultural commodities, specifically focusing on citrus fruits like oranges. 'Greening' is the process of removing the green pigmentation or chlorophyll from the fruit peel, which enhances its visual appeal to consumers. The method commonly employs ethylene gas or temperature treatments to speed up the process. It's crucial to note that only mature fruits with appropriate acid and sugar levels are suitable for 'Greening,' as immature fruits do not meet quality standards and citrus fruits do not continue to ripen post-harvest. The natural 'Greening' of citrus fruit skin occurs due to chlorophyll degradation by ethylene on the tree, especially during cooler late-autumn nights. However, in some cases, mature Valencia oranges can 'regreen' in summer due to heat. The paragraph also outlines the considerations for effective 'Greening,' such as ensuring fruit maturity, applying fungicides to prevent post-harvest treatments, managing ethylene doses, monitoring carbon dioxide levels, and maintaining high humidity. It concludes by clarifying that 'Greening' does not improve the eating quality of the fruit and differentiates the process from the use of calcium carbide or curu.

05:00

🔁 Comparing Ethylene and Calcium Carbide in Fruit Ripening

The second paragraph discusses the differences between ethylene and calcium carbide in the context of fruit ripening. Calcium carbide, when reacting with moisture, produces acetylene gas, which acts similarly to ethylene as an artificial ripening agent. However, it is highlighted that acetylene is less effective than ethylene and requires a larger quantity to achieve the same results. The paragraph concludes the topic of 'Greening' by briefly mentioning this comparison and thanking the viewers for their attention.

Keywords

💡Greening

The term 'Greening' in the context of the video refers to the process of removing the green pigmentation or chlorophyll from the peel of certain fruits, particularly citrus fruits like oranges, to make them more visually appealing to consumers. This process is essential for agricultural commodities in AB materials and is a key theme of the video, illustrating how fruits are treated to meet consumer expectations and standards for appearance. The script mentions that 'The Greening refers to the process applied to certain fruits, especially citrus fruits like oranges' and discusses the methods used to achieve this, such as ethylene gas or temperature treatments.

💡Chlorophyll

Chlorophyll is the green pigment found in plants, including the peel of citrus fruits, which is responsible for their green color. In the video, chlorophyll degradation is a natural process that occurs as the fruit ripens, and it is accelerated through the 'Greening' process to enhance the fruit's appearance. The script states that 'chlorophyll is the green color in plants and is responsible for the green color in Citrus fruit', highlighting its importance in the context of the 'Greening' process.

💡Ethylene

Ethylene is a plant hormone that plays a crucial role in the ripening of fruits. In the video, ethylene gas is used to accelerate the 'Greening' process by promoting the degradation of chlorophyll in the fruit peel. The script explains that 'this process typically uses ethylene gas or temperature treatments to accelerate the de-Greening process', emphasizing its effectiveness in making the fruit peel more visually appealing.

💡Degreening

Degreening is the process of removing the green color from the peel of citrus fruits, making them appear ripe and ready for consumption. The term is used in the video to describe the specific treatment applied to mature fruits to enhance their appearance. The script mentions that 'only fruit that meets Australian Citrus standards or ACS should be degreened in the packing shell', indicating the importance of this process in the agricultural industry.

💡Mature Fruit

Mature fruit refers to fruit that has fully developed and reached the appropriate stage for consumption. In the context of the video, only mature fruit with more than 50% color development is suitable for the 'Greening' process. The script states that 'only mature fruit is suitable for de-Greening' because immature fruit has high acid levels and low sugar levels, which do not meet the desired standards.

💡Citrus Fruit

Citrus fruit is a category of fruits that includes oranges, lemons, and other similar varieties. The video focuses on the 'Greening' process as it applies to citrus fruits, particularly oranges. The script uses the example of an orange, stating that 'an orange is meant to be orange and people want to buy a yellow lemon', to illustrate the consumer expectations regarding the appearance of these fruits.

💡Temperature Treatments

Temperature treatments are methods used to manipulate the ripening process of fruits, including the 'Greening' process. The video mentions that these treatments, along with ethylene gas, are used to accelerate the removal of chlorophyll from the fruit peel. The script specifies that 'this process typically uses ethylene gas or temperature treatments to accelerate the de-Greening process', indicating the role of temperature in influencing fruit appearance.

💡Australian Citrus Standards (ACS)

The Australian Citrus Standards (ACS) are guidelines that dictate the quality and appearance criteria for citrus fruits in Australia. The video emphasizes that only fruits meeting these standards should undergo the 'Greening' process. The script states that 'only fruit that meets Australian Citrus standards or ACS should be degreened in the packing shell', highlighting the importance of adhering to these standards in the industry.

💡Carbon Dioxide

Carbon dioxide (CO2) is a byproduct of the respiration process in harvested fruit. In the context of the video, it is important to monitor CO2 levels during the 'Greening' process because high concentrations can inhibit the de-Greening process and pose safety risks for people in the room. The script advises to 'Monitor carbon dioxide in the room and regularly vent', underscoring the need for proper ventilation during this process.

💡Relative Humidity

Relative humidity is a measure of the amount of moisture in the air compared to the maximum amount the air can hold at a given temperature. The video highlights the importance of maintaining high relative humidity levels during the 'Greening' process to prevent excessive fruit weight loss. The script specifies that 'the relative humidity in the de-Greening room should be around 95%', indicating the optimal conditions for this process.

💡Calcium Carbide

Calcium carbide, also known as 'curu', is a chemical compound that reacts with moisture to produce acetylene gas, which is used as an artificial ripening agent. The video differentiates between calcium carbide and ethylene gas, noting that acetylene is less effective and requires a larger quantity for the same effectiveness as ethylene. The script mentions that 'calcium carbide or curu reacts with the moisture to produce acetylene gas which mimic the action of ethylene', providing context on the use of different chemicals in the ripening process.

Highlights

The Greening process is applied to certain fruits, especially citrus fruits like oranges, to enhance their visual appeal.

It involves the removal of green pigmentation or chlorophyll from the fruit peel.

The Greening process uses ethylene gas or temperature treatments to accelerate de-greening.

Only mature fruit with suitable acid and sugar levels is suitable for the Greening process.

Citrus fruit is non-climatic, meaning it does not continue to ripen after harvest.

Chlorophyll degradation by ethylene is a natural process that can be accelerated artificially.

The Greening process is temperature-dependent, with cooler night temperatures in late Autumn facilitating the change.

Mature Valena oranges can regreen in summer due to heat after a natural color has begun.

Fruit that meets Australian Citrus standards should be used for the Greening process in the packing shell.

The fruit should be mature with more than 50% color development for the best Greening outcome.

Applying an initial fungicide prevents post-harvest treatments and is a step in the Greening process.

Fruit harvested within 6 weeks of an oil spray are slower to Green.

Controlled doses of ethylene are injected into the room during the Greening process.

Higher doses of ethylene do not necessarily speed up the Greening process.

Monitoring carbon dioxide levels in the room is crucial for the Greening process and safety.

High humidity levels of around 95% are maintained during the Greening process to prevent excessive fruit weight loss.

The Greening process does not improve the eating quality of the fruit; it's purely for visual enhancement.

Calcium carbide or curu reacts with moisture to produce acetylene gas, which is used as an artificial ripening agent.

Acetylene is less effective than ethylene and requires a larger quantity for the same effectiveness.

Transcripts

hi and Welcome to our AB 313 properties

of ab materials so our topic for today

is about The

[Music]

Greening so what is The Greening in

terms of agricultural Commodities in AB

materials The Greening refers to the

process applied to certain fruits

especially citrus fruits like oranges it

involves the removal of green

pigmentation or chlorophyll from the

fruit peel making the fruit more

visually appealing to

Consumers this process typically uses

ethylene gas or temperature treatments

to accelerate the de Greening

process remember it is important to note

that only mature fruit is suitable for

deg Greening the reason is twofold first

immature fruit has very high acid levels

and low sugar levels

which do not meet its standard and

second citrus fruit is non-climatic this

means that unlike Tomatoes peaches or

pineapples it will not continue to ripen

after the

[Music]

Harvest so how does it work for example

according to Citrus Australia an orange

is meant to be orange and people want to

buy a yellow lemon but at a certain time

of the year citrus fruit do not lose

their green skin color on the tree even

though the fruit is ready to

eat chlorophyll is the green color in

plants and is responsible for the green

color in Citrus fi The Greening of the

skin is a natural process of chlorophyll

degradation by Ethylene on the tree The

Greening of the peel happens when the

night temperature are cooler in late

Autumn although the fruit may be mature

inside and ready to eat the weather may

be too warm for natural Ren color

development meanwhile a similar process

but in Reverse can happen with mature

Valena oranges in summer where the fruit

can regreen to Coke with the

heat after a natural color has begun

only fruit that meets Australian Citrus

standards or ACS should be degreened in

the packing

shell and here are the things to

consider during the degreening process

for best outcome first ensure the fruit

is mature with more than 50% color fruit

with more than 50% color development the

green well

fruit with dark green blood shells will

not color well after harvest Branch the

fruit with an initial fungicide to

prevent post Harvest trat do not apply

walks fruit harvested within 6 weeks of

an oil spray are slower to

Green next is after the fungicide rench

let the fruit dry and load the fruit

Into The deg Greening

room after the drying add as

controlled doses of ethylene are

injected into the room to maintain 1 to

five parts per million fanss evenly

distributed the ethylene around the room

note that the higher doses of ethylene

do not speed up the degreening process

for example during the autumn in

Australia they maintain only a

temperature of 20 to 25° C up to 29° C

which is suitable for for The Greening

fruit from the humid subtropical

regions and next is Monitor carbon

dioxide in the room and regularly vent

harvested fruit is still breathing and

giving up carbon dioxide into the room

this carbon dioxide can inhibit the

degreening process and also reaching

unsafe levels for people entering the

room and the last is keep humidity

levels high at 95% relative humidity the

relative humidity in the degreening room

should be around 95 % fruit weight loss

is excessive when humidity levels are

lower than 90% after de Greening weight

for 12 hours to 24 hours and the fruit

can be run over the Ping line and graded

take note that The Greening process does

not improve the eating quality of a

fruit people may get confused about what

is familiar with us which is the calcium

carbide or curu and the ethylene gas

that is used in the process of De

Greening so what it's different from

each other calcium carbide or curu

reacts with the moisture to produce

ayline gas which mimic the action of

ethylene and is used as an artificial

ripening agent however acetylene is not

effective as ethylene a much larger

quantity must be used for the same

Effectiveness and that is all for our

topic The Greening thank you for

watching

[Music]