How to get bromelain out of pineapple?

Did you know that the stinging or tingling sensation from eating fresh pineapple is caused by the protein-digesting enzyme, bromelain? Getting bromelain out of pineapple is a straightforward process, relying on either heat to deactivate the enzyme or mechanical methods to separate it, and is essential for preventing the characteristic mouth burn and enabling certain recipes.

Quick Summary

Bromelain's activity can be eliminated with heat through cooking, grilling, or boiling. Alternatively, it can be separated from the fruit using simple crushing and filtering, or through complex industrial processes involving ultrafiltration and precipitation.

Key Points

• Heat Inactivation: The easiest way to remove bromelain activity at home is by cooking, grilling, or boiling the pineapple, which denatures the enzyme.

• Basic Home Extraction: For a crude bromelain liquid, blend pineapple parts (including core and peels) with water and strain through a filter to separate solids.

• Source of Bromelain: The highest concentration of bromelain isn't just in the fruit pulp, but often in the fibrous core and stem, with unripe fruit containing higher levels.

• Industrial Methods: High-purity bromelain is commercially produced using advanced techniques like ultrafiltration and ammonium sulfate precipitation.

• Preventing Mouth Burn: Cooking pineapple fully is the simplest method for home cooks to prevent the tingling sensation caused by the protein-digesting enzymes.

Inactivating Bromelain with Heat

For most home cooks, the easiest method to remove the active bromelain from pineapple is by denaturing it with heat. The enzyme is thermolabile, meaning its protein structure and, therefore, its function are destroyed at high temperatures. This is particularly useful when making dishes that rely on protein coagulation, such as gelatin-based desserts, which fresh pineapple would prevent from setting. The following methods are effective for heat inactivation.

Cooking and Grilling

Applying heat directly to pineapple, such as through grilling or baking, effectively deactivates the bromelain. The high temperatures break down the enzyme, which also softens the fruit and caramelizes its natural sugars.

• Grilling: Slice pineapple into rings or spears and grill them over medium-high heat until caramelized and tender. This is a simple, effective method for delicious, burn-free pineapple.
• Baking: Incorporating pineapple into baked goods, like pineapple upside-down cake or pies, ensures the fruit is cooked thoroughly, rendering the bromelain inactive.

Boiling or Simmering

Boiling pineapple is another surefire way to denature the enzyme. The temperature required is well below the boiling point of water, with research indicating inactivation around 70°C (158°F).

1. Cut the pineapple into chunks or pieces.
2. Place the pineapple in a saucepan and cover with water.
3. Bring the water to a boil, then reduce heat and simmer for at least 10-15 minutes.
4. The boiled pineapple or juice can then be used in recipes without the risk of enzyme activity.

Basic Home Extraction Methods

For those seeking to extract and use crude bromelain, rather than destroy it, a mechanical process can separate the enzyme from the fibrous fruit material. This is not for high-purity extraction but can be used for purposes like making pineapple-infused water or tonics. Bromelain is found in multiple parts of the fruit, including the core and peel, which contain significant amounts.

Crushing and Filtering

This simple method separates the liquid containing bromelain from the solid fibers. It is best performed with a ripe or partially ripe pineapple, as the enzyme content decreases with full maturation.

1. Prepare the pineapple: Wash the pineapple thoroughly and chop the flesh, core, and peel into small pieces.
2. Crush or blend: Use a blender, mortar and pestle, or juicer to crush the pineapple parts and release the liquid.
3. Filter the liquid: Strain the resulting mixture through a fine-mesh sieve or several layers of cheesecloth to separate the solids from the juice.
4. Centrifugation (optional): At home, you can let the liquid settle in the refrigerator to allow solids to collect at the bottom. This is a very basic form of clarification, not centrifugation.

Making a Pineapple Tonic

A folk method for extracting the enzymes and nutrients from the pineapple peels and core involves simmering them at a lower temperature to preserve some enzymatic activity.

• Ingredients: Pineapple peels, core, water, and optional spices like cinnamon.
• Instructions: Wash the peels thoroughly. Add the peels, core, and water to a pot. Bring to a boil, then reduce heat and simmer for about 20 minutes. Strain the liquid, and you have a bromelain-rich tonic. For higher enzyme activity, a cold-soak extraction is preferred over simmering.

Advanced Industrial Bromelain Extraction

Industrial extraction methods are designed for high purity and yield, far exceeding what is possible with household equipment. These processes are crucial for producing bromelain supplements and commercial enzymes. Techniques include:

• Centrifugation and Ultrafiltration: After crushing, the pineapple juice is centrifuged to remove insoluble solids. The liquid is then passed through membranes of varying pore sizes (ultrafiltration) to concentrate and purify the bromelain.
• Ammonium Sulfate Precipitation: This salting-out method precipitates the protein from the solution by adding ammonium sulfate salt. The precipitate is then collected and redissolved for further processing.
• Chromatography: Highly refined purification uses various chromatographic techniques to separate bromelain from other proteins based on charge, size, or other properties.

Comparing Bromelain Inactivation and Extraction

This table summarizes the different methods for handling bromelain from pineapple based on the desired outcome.

Method	Purpose	Equipment	Bromelain State	Yield/Purity
Heat Inactivation	Eliminates bromelain activity	Grill, oven, saucepan	Inactive (denatured)	N/A (destroyed)
Basic Home Extraction	Creates a crude bromelain-containing liquid	Blender, strainer, cheesecloth	Active (crude extract)	Low yield, very low purity
Industrial Extraction	Produces high-purity bromelain for supplements	Centrifuge, ultrafiltration membranes, lab equipment	Active (purified extract)	High yield, high purity

Conclusion

For everyday kitchen applications where active bromelain is undesirable—like making gelatin or preventing mouth soreness—heat inactivation is the simplest and most effective solution. A quick boil, bake, or grill session is all it takes. If you're interested in using the enzymes in a liquid form for a tonic or other crude extract, simple mechanical methods like blending and straining the fruit, including the core and peels, will suffice. However, for a high-purity bromelain supplement, a complex industrial extraction process is required, which is not feasible for home preparation. The best approach depends entirely on your end goal, whether it's simply cooking a delicious, burn-free meal or creating a homemade tonic using the plant's valuable enzymes.

Other Considerations for Bromelain

• Ripeness: The level of bromelain activity in pineapple can vary depending on its ripeness. Research suggests that partially ripe fruit may contain higher levels of the enzyme.
• Source: For industrial production, bromelain is more commonly and efficiently extracted from the pineapple stem, though significant amounts are also found in the fruit, core, and peel. Home extraction can effectively use the core and peel, which are often discarded.
• Stability: Bromelain is relatively stable but is sensitive to high temperatures, with its activity decreasing significantly above 60°C (140°F).

Further Reading

For more in-depth scientific information on bromelain extraction and properties, the National Institutes of Health (NIH) is a valuable resource.

Frequently Asked Questions

How does cooking pineapple remove bromelain?

Cooking pineapple effectively removes bromelain by subjecting it to high heat, which denatures or destroys the enzyme's protein structure, rendering it inactive.

Can I get bromelain out of pineapple without cooking it?

Yes, you can separate the enzyme from the fibrous fruit through a mechanical process like blending and filtering. This yields a crude liquid extract containing the active enzyme, not a high-purity powder.

Does soaking pineapple in salt water remove bromelain?

While some folk remedies suggest soaking pineapple in salt water to reduce the stinging sensation, this is not a scientifically proven method for removing or significantly inactivating the bromelain enzyme.

Is bromelain dangerous?

Bromelain is generally considered safe. The mouth tingling it causes is a normal reaction to its protein-digesting action. Serious allergic reactions are rare but possible. People with kidney or liver disorders should consult a doctor before taking bromelain supplements.

Which part of the pineapple contains the most bromelain?

The core and stem of the pineapple contain high concentrations of bromelain. While the flesh also contains it, the more fibrous parts are significant sources for commercial extraction.

Why does fresh pineapple prevent gelatin from setting?

Fresh pineapple prevents gelatin from setting because its active bromelain enzyme breaks down the collagen protein in the gelatin. Cooking the pineapple first will inactivate the bromelain and allow the gelatin to set properly.

Does canned pineapple contain bromelain?

No, commercially canned pineapple does not contain active bromelain. The heat used during the canning and pasteurization process deactivates the enzyme completely, so it will not interfere with recipes like gelatin.