Harvest Keep Air Out 500 cc

Harvest Keeper Air Out Oxygen Absorbers are single-use packets filled with powdered iron that chemically bind to free oxygen in a sealed container. Each bag contains 25 packets at the 500 cc size, capable of absorbing 500 cubic centimeters of oxygen in a confined space. They are food safe, release no harmful gases or toxic byproducts, and help extend shelf life by reducing the oxygen that supports mold, mildew, and aerobic bacterial growth.

Harvest Keep Air Out 500 cc Specifications

Specification	Value
Brand	Harvest Keeper
Product Line	Air Out Oxygen Absorbers
Absorber Capacity	500 cc (cubic centimeters)
Packet Dimensions	3.25 in x 2.875 in x 0.125 in
Quantity per Bag	25 packets
Active Ingredient	Specific powdered iron compound
Food Safe	Yes — releases no harmful gases or toxic elements
Supplier SKU	744654

Why Choose Harvest Keep Air Out 500 cc

Oxygen absorbers work differently from silica gel desiccants or vacuum sealing alone. Rather than removing moisture or physically pulling air out of a container, oxygen absorbers chemically react with free oxygen molecules in the sealed space, converting them to iron oxide. Once the available oxygen is consumed, the chemical reaction stops. The result is a container atmosphere composed almost entirely of nitrogen, which is inert and does not support the biological processes that degrade stored material.

The 500 cc size is well-matched for mid-volume storage containers — larger than a mason pint jar but smaller than a full gallon vessel. Each packet absorbs 500 cubic centimeters of oxygen, which corresponds to roughly the oxygen content in a quart-to-half-gallon range sealed container, depending on how tightly the contents are packed. For growers storing harvested material in quart or half-gallon glass jars or food-grade bags, the 500 cc packet handles the headspace and interstitial air without needing multiple packets per container.

The food-safe formulation is an important detail for anyone storing consumables. The powdered iron in each packet does not release gases, off-gassing compounds, or toxic residues. The packet material is designed to allow oxygen to pass through while keeping the iron powder contained. You can place a packet directly into a container with dried material without contamination risk from the absorber itself.

• Powdered iron chemistry: Active ingredient reacts directly with oxygen molecules rather than simply adsorbing moisture, creating a low-oxygen environment suitable for long-term storage.
• Food-safe construction: No harmful gases or toxic elements are released into the storage container; safe for use with dried consumables and botanicals.
• Inhibits spoilage organisms: Reduced oxygen levels limit the growth of molds, mildew, and aerobic bacteria that require oxygen to thrive.
• Flavor and aroma retention: By slowing oxidative degradation, oxygen absorbers help preserve the volatile compounds responsible for flavor and aroma in dried botanical materials.
• Right-sized for mid-volume containers: The 500 cc capacity is appropriate for quart-to-half-gallon containers; larger than small packets but not oversized for the application, which avoids wasting absorber capacity.
• 25-count pack: Each bag contains 25 individual packets, enough to treat multiple containers in a single harvest session without sourcing individual packets.

Best Uses for Harvest Keep Air Out 500 cc

The primary application for 500 cc oxygen absorbers is post-harvest storage of dried botanicals, herbs, and similar plant material in sealed containers. Growers who cure and store harvested material in glass jars, food-grade plastic containers, or vacuum-sealable bags will find these absorbers useful for extending the period during which stored material retains its original quality. The absorbers are most effective when the container is sealed promptly after the packet is inserted, giving the iron compound as little time as possible to react with ambient air before the container is closed.

• Dried botanical and herb long-term storage: Place one packet in a quart or half-gallon sealed jar with dried plant material to reduce oxygen content and slow oxidative and biological degradation over weeks and months.
• Post-harvest curing containers: Use during and after the curing phase to maintain the low-oxygen environment that slows mold development in tightly sealed containers, particularly important in high-humidity storage conditions.
• Food-grade dry goods storage: The food-safe formulation makes these suitable for use with dried foods, grains, seeds, and spices stored in sealed containers for pantry or long-term food storage.
• Seed preservation: Storing seeds in low-oxygen environments reduces respiration rates and slows degradation of viability over time; a single 500 cc packet can treat a quart-size seed storage container.
• Specimen archiving: Dried plant specimens, samples, or materials that need to be stored for later analysis can benefit from the reduced-oxygen atmosphere for maintaining physical integrity.

The 500 cc size is a middle-ground option in the Air Out line. If you regularly store material in smaller containers such as 4-ounce or half-pint jars, the 50 cc or 100 cc sizes would be a better match to avoid over-absorption. For gallon or larger containers, consider multiple 500 cc packets or a larger capacity absorber. Matching absorber capacity to container volume is important: too little oxygen absorption leaves residual oxygen that can still support spoilage, while excessive capacity is simply waste since the packets are single-use.

Compatibility

Harvest Keep Air Out oxygen absorbers are compatible with any airtight sealed container that does not continuously exchange air with the environment. They work in glass jars with airtight lids, food-grade PETE or HDPE plastic containers with sealed lids, heat-sealed mylar bags, and vacuum-sealed pouches. The critical requirement is that the container provides a sufficiently airtight seal; if air can continuously enter, the absorber will be exhausted before the oxygen concentration drops to an effective level.

These absorbers are not appropriate for use in containers that are not sealed or that are regularly opened for extended periods. Once exposed to open air, the absorber begins reacting immediately. Packets should be used promptly after the outer bag is opened, and any unused packets from an opened bag should be resealed in an airtight container or zip-lock bag immediately to preserve their remaining capacity.

If you are using vacuum-sealed storage bags as part of your post-harvest process — for example, the kind used with a vacuum sealer for long-term storage — oxygen absorbers provide a complementary layer of protection. Vacuum sealing removes the bulk of the air mechanically, and an oxygen absorber handles residual oxygen that the vacuum pump cannot remove. For growers using CVault airtight cure containers or similar airtight curing and storage solutions, adding an oxygen absorber provides an extra measure of protection against residual oxygen in the headspace.

Do not use oxygen absorbers in containers with high-moisture content products, as the combination of low oxygen and high humidity can create conditions favorable to anaerobic organisms. Oxygen absorbers are designed for use with dry goods at low moisture content (generally below 10% moisture by weight). For dried botanicals that have been cured to an appropriate moisture level, these conditions are typically met.

Usage Guidelines

Oxygen absorbers are straightforward to use but sensitive to timing. The iron in each packet begins reacting with oxygen as soon as the outer packaging is opened. For best results, plan ahead so you can move from opening the outer bag to sealing your storage containers within a few minutes. Have your containers and material ready before opening the outer bag of absorbers.

Determining the right number of packets per container: Each 500 cc packet absorbs approximately 500 cubic centimeters of free oxygen. Standard atmosphere is about 21% oxygen, so a 500 cc packet is roughly matched to a 2.4-liter (about half-gallon) fully sealed container at ambient air fill. In practice, containers filled with material have significantly less headspace, so a single 500 cc packet will typically cover a quart jar with moderate fill or a half-gallon jar that is well-packed. For less-packed containers or larger headspace, use two packets. When in doubt, a second packet adds insurance; the absorber capacity cost is low relative to the value of the stored material.

Handling unused packets: If you open the 25-count bag and use fewer than all 25 packets, the remaining packets should be resealed immediately in an airtight container or heavy-duty zip-lock bag. Leaving them exposed to ambient air will exhaust their capacity before the next use. Depleted packets cannot be reactivated; once the iron compound is fully oxidized, the packet is spent.

Confirming packet activity: Fresh packets feel slightly soft and pliable. Depleted or spent packets become noticeably hard and rigid as the iron compound forms iron oxide. If packets from an opened bag have hardened, they should not be used as their absorbing capacity has been compromised.

How to Use Harvest Keep Air Out Oxygen Absorbers

1. Prepare your storage containers: Ensure the dried material to be stored is at the appropriate moisture content (properly dried and, for botanicals, cured to target humidity). Containers should be clean, dry, and have an airtight seal.
2. Gather materials before opening: Have all containers, lids, and materials ready before you open the outer bag of oxygen absorbers. Lay them out so you can work quickly once the outer bag is opened.
3. Open the outer bag and work promptly: Remove only the number of 500 cc packets you plan to use immediately. Place any remaining packets back into the outer bag and reseal it in an airtight container right away.
4. Place one packet per container: Drop one 500 cc absorber packet into each container on top of the stored material, or set it alongside the material in the headspace. The packet does not need to be buried; it works throughout the sealed space.
5. Seal the container immediately: Close and seal the container as quickly as possible after the packet is inserted. For jar lids, tighten firmly. For bags, heat-seal or vacuum-seal promptly.
6. Label and store: Mark the container with the date sealed. Store in a cool, dark location. The oxygen absorber will complete its work within 1–4 hours of sealing in most cases, depending on container volume and initial oxygen content.
7. Inspect before reuse: When you open a container that contained an absorber, the used packet will be rigid and hard — this is normal and confirms it functioned. Discard used packets; they are not rechargeable. If you will reseal the container for continued storage, place a fresh packet inside before resealing.

For growers using timed grow-room equipment or planning larger harvests, consider pairing oxygen absorbers with a structured post-harvest workflow. Products like the Advanced Nutrients pH Perfect Sensi Bloom series are part of a broader approach to maximizing the quality of what you grow; oxygen absorbers help protect that quality after harvest, during storage.

Sources & Further Reading