Preserve Mangoes: 4 Tips to Prevent Discoloration After Cutting
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Preserving the vibrant and enticing colour of freshly cut mangoes can be a challenge, as they tend to darken quickly upon exposure to air. The sight of a dull and discoloured mango can be disappointing, especially when you're aiming to present a visually appealing dish or simply savour the fruit's natural beauty.

However, fear not! In this article, we will explore a collection of practical tips and tricks to help you prevent mangoes from darkening after cutting. From simple household ingredients to expert techniques, let's uncover the secrets that will ensure your mangoes remain radiant and appetising, allowing you to fully enjoy their succulent sweetness without the worry of discolouration.

Why Do Mangoes Turn Dark After Cutting?

Mangoes turn dark after cutting due to a process called enzymatic browning. Enzymatic browning occurs when the enzyme polyphenol oxidase (PPO), present in the fruit, comes into contact with oxygen in the air. This interaction triggers a series of chemical reactions that lead to the oxidation of phenolic compounds naturally present in the mango's flesh. As a result, the fruit undergoes a colour change, turning brown or darkening in patches.

Enzymatic browning is a natural occurrence in many fruits and vegetables, including mangoes, apples, bananas, and avocados. While it doesn't affect the safety or taste of the fruit, the darkened appearance may be unappealing and give the impression that the mango is overripe or spoiled.

Factors such as exposure to air, temperature, and acidity levels can accelerate enzymatic browning in mangoes. Cutting or bruising the fruit exposes more surface area to oxygen, increasing the chances of browning. Higher temperatures and alkaline pH levels also tend to speed up enzymatic browning reactions.

Understanding the process of enzymatic browning and utilising certain ingredients can help in implementing effective techniques to prevent or minimise the darkening of cut mangoes and maintain the natural, vibrant colour of freshly cut mangoes for longer periods of time.

Tips And Tricks To Avoid Darkening Of Mangoes

Pick The Right Type Of Mangoes

Selecting the right types of mangoes is crucial when it comes to avoiding darkening and preserving the quality of cut mangoes for later use. Different mango varieties have varying characteristics, including their enzyme activity and susceptibility to browning. By choosing mangoes with specific qualities, you can significantly impact their shelf life and appearance after cutting.

Certain mango cultivars, such as Tommy Atkins and Kent, are known for their relatively low enzyme activity, which means they are less prone to browning when exposed to air. These varieties tend to retain their bright colour even when cut and stored for a longer time. On the other hand, some mango varieties, like Alphonso or Ataulfo, have higher enzyme activity and may darken more quickly after cutting.

Furthermore, the ripeness of the mango at the time of cutting can also affect browning. It is generally recommended to choose mangoes that are ripe but still firm for cutting and storing. Overripe mangoes have higher enzyme activity and are more likely to brown rapidly. By selecting mangoes at the right stage of ripeness, you can extend their shelf life and delay the onset of enzymatic browning.

Additionally, it is essential to handle mangoes gently to minimise bruising and damage to the fruit's flesh. Any physical injury to the mango can accelerate enzymatic browning reactions. Therefore, opt for mangoes that are free from bruises or blemishes, as they are less likely to darken quickly. By considering the type of mango and its ripeness, you can choose varieties that are naturally more resistant to browning. This selection process enables you to enjoy visually appealing and fresh-looking cut mangoes even when storing them for later use.

Cut The Mangoes Properly

The way you cut the fruit can greatly impact its exposure to air, which is a key factor in enzymatic browning. By following some essential techniques, you can maintain the freshness and appealing appearance of mangoes after cutting.

To begin, it is important to use a sharp knife when cutting mangoes. A dull knife can cause bruising and damage to the fruit, which can accelerate enzymatic browning. A sharp knife allows for clean cuts, reducing the likelihood of injury to the mango's flesh. Start by cutting off both ends of the mango to create stable, flat surfaces. This will help prevent the mango from rolling while you work with it. Next, hold the mango upright on one of its flat ends and, using a downward motion, slice along the sides of the seed. This technique should yield two mango halves.

Once you have the mango halves, scoring the flesh can be beneficial. Use a knife to create shallow, crisscross cuts in the flesh of each half. Be careful not to cut through the skin. Scoring the flesh allows for easier removal of mango cubes later while keeping the fruit intact. To extract the mango cubes, use a spoon. Gently scoop out the scored mango flesh by starting at one end and sliding the spoon between the skin and the fruit. Repeat the process for the other mango half. This method helps separate the flesh from the skin while minimising contact with air.

If you plan to store the mango halves for later use, it is advisable to keep the skin intact. This helps protect the cut surfaces from direct exposure to air. Place the mango halves, cut side down, on a plate or store them in an airtight container. For cut mango cubes, transfer them to an airtight container or a sealable bag.

Squeeze out any excess air before sealing the container to reduce oxygen exposure, which can lead to faster browning.

After cutting the mangoes, refrigerate them promptly. The cool temperature of the refrigerator slows down enzymatic browning, helping to preserve the mango's colour and freshness for a longer duration.

Use An Acid To Protect The Mangoes

Protecting mangoes from oxidation using acids is an effective method to prevent or slow down enzymatic browning. Acids work by denaturing the enzyme responsible for browning, thus preserving the fruit's colour and freshness. One popular acid that is commonly used is citrus juice, such as lemon or lime juice.

These juices have a high citric acid content, which lowers the pH level and creates an acidic environment. This acidic environment inhibits the activity of the browning enzyme, helping to maintain the mangoes' vibrant colour. To protect cut mangoes from oxidation, you can lightly drizzle or brush the mango slices with citrus juice, ensuring that all exposed surfaces are coated. The juice acts as a barrier, minimising contact between the fruit and the oxygen in the air.

Another option for using acids to protect mangoes is vinegar, such as white vinegar or apple cider vinegar. Vinegar is also acidic and can help prevent enzymatic browning. To use vinegar, dilute it with water and create a solution in which you can soak the cut mangoes for a few minutes. The acidity of the vinegar solution creates an unfavourable environment for the browning enzyme, reducing the likelihood of discolouration. After soaking, drain the mangoes and pat them dry before storage or further use.

It is important to note that while using acids can be effective in preventing browning, it may slightly alter the taste of the mangoes. Citrus juices like lemon or lime can impart a tangy flavour, while vinegar may add a slight acidity. Therefore, consider the overall taste profile you desire when deciding which acid to use and in what concentration.

Regardless of the acid you choose, it is advisable to refrigerate the mangoes after applying the acid treatment. Cold temperatures further slow down enzymatic browning reactions, helping to extend the mangoes' shelf life and maintain their appearance.

Store Them Properly

Proper storage is key to preventing mangoes from darkening and maintaining their fresh appearance. When it comes to storing mangoes, a few important steps can help minimise browning and preserve their quality. Firstly, it is crucial to select ripe but firm mangoes for storage. Overripe mangoes tend to have higher enzyme activity, making them more prone to browning. With ripe mangoes that are still firm to the touch, you can ensure they have a longer shelf life and are less likely to darken quickly after cutting.

Mangoes are best kept in a cool environment, such as the refrigerator. The low temperature of the fridge slows down enzymatic browning reactions, helping to preserve the mangoes' natural colour and freshness. However, it's worth noting that refrigeration may affect the texture of the mangoes, making them slightly firmer. If you prefer a softer texture, you can store them at room temperature for a short period of time, but be aware that they may darken more quickly.

When storing mangoes, it is important to keep them separate from other fruits. Mangoes release ethylene gas, a natural ripening hormone that can accelerate the ripening process of nearby fruits. To avoid premature ripening and potential browning, store mangoes separately or place them in a breathable bag to contain any ethylene gas they produce.

Additionally, to further protect mangoes from darkening, you can consider wrapping them individually in paper towels. The paper towels help absorb excess moisture and reduce the amount of moisture on the mangoes' surface, which can contribute to browning. This method can be especially helpful if you plan to store cut mangoes.

If you have already cut the mangoes, it is important to store them properly to minimise darkening. Place the cut mangoes in an airtight container or wrap them tightly in plastic wrap, ensuring there is minimal exposure to air. This method helps prevent oxidation and slows down enzymatic browning.

Use Anti-Browning Agents

There are natural anti-browning agents available that can help preserve the colour of mangoes. One option is using commercial fruit anti-browning products that contain natural enzymes or antioxidants. These products can be sprayed or brushed onto the mango slices to inhibit browning. Another natural option is dipping the mango slices in pineapple or orange juice, as both fruits contain enzymes that can slow down browning.

With these simple yet effective tips, you can prevent mangoes from discolouring after cutting, ensuring that they remain fresh, vibrant, and visually appealing. By selecting ripe and firm mangoes, cutting and storing them properly, treating them with acidic solutions, refrigerating promptly, and using anti-browning agents, you can enjoy beautifully preserved mango slices for a longer period of time.