The process of storing a fresh tomato harvest presents a unique challenge for the home gardener. Unlike many other types of produce that tolerate cold storage, the tomato, botanically a fruit, is highly sensitive to temperature fluctuations. Maintaining the peak flavor, vibrant aroma, and firm texture achieved through vine-ripening requires specific handling immediately after harvest. Successful storage relies on understanding the tomato’s biology to preserve its quality for short-term enjoyment or long-term preservation.
Essential Preparation for Storage
Begin by gently sorting the tomatoes and setting aside any that are bruised, cracked, or showing signs of mold, as damaged fruit will accelerate the spoilage of others. Avoid washing whole tomatoes before storage because residual moisture encourages mold and bacteria growth near the stem scar. Instead, use a clean, soft cloth or paper towel to wipe away any excess dirt or debris from the surface of the fruit.
Leaving the small, green stem cap, or calyx, attached to the tomato can also be beneficial. The attachment point where the stem was removed is a vulnerable area where moisture escapes and pathogens enter. Keeping the calyx on helps to seal this area, reducing moisture loss and slowing down the decay process. To maximize quality, keep fully ripe tomatoes out of the refrigerator, as cold temperatures compromise their flavor and texture.
Short-Term Storage for Ripe Tomatoes
Ripe tomatoes retain their best quality when stored at room temperature, ideally between 55°F and 70°F (13°C and 21°C). Temperatures below this range initiate a physiological disorder known as chilling injury, which degrades quality.
Exposure to typical refrigerator temperatures (around 40°F/4°C) stimulates the decay of firmness and alters the fruit’s chemical composition. Cold storage causes a decrease in sugar content and an increase in acid content, resulting in a muted flavor. Chilling can also permanently damage cell walls, leading to the mealy or mushy texture often associated with refrigerated tomatoes.
To minimize moisture loss, place the tomatoes stem-side down on a flat surface. This position uses the tomato’s weight to protect the stem scar and can help keep the fruit firm for up to a week. Refrigeration should only be considered a last resort for extremely overripe tomatoes that must be preserved for a day or two, or for any tomatoes that have been sliced or cut.
Strategies for Ripening Green Tomatoes
Green tomatoes, often harvested due to the threat of frost, can be ripened indoors using controlled methods. Ripening is driven by ethylene, a natural plant hormone and gas produced by tomatoes. This process is temperature-dependent and is halted completely when temperatures fall below 50°F (10°C).
Gradual Ripening
For a gradual and extended supply, green tomatoes can be wrapped individually in newspaper and placed in a single layer inside a cardboard box. Storing these boxes in a dark, cool environment (55°F to 65°F / 13°C to 18°C), such as a basement or garage, slows the release of ethylene. This technique staggers the ripening process, allowing the fruit to gradually turn red over several weeks or even months.
Accelerated Ripening
To speed up the ripening of a batch, create a higher concentration of ethylene gas by placing the green tomatoes in a paper bag or closed container with a ripe climacteric fruit like an apple or a banana. The additional ethylene released by these fruits acts as a catalyst, encouraging the tomatoes to ripen more quickly. The ideal temperature for this accelerated ripening is slightly warmer, around 60°F to 75°F (15°C to 24°C). Monitor the container daily and remove any tomatoes that are fully ripened or show signs of decay to prevent mold from spreading.
Long-Term Preservation Options
When the garden yields a large surplus, preservation methods store the bounty for months or years.
Canning
Canning is a traditional and highly effective method for preserving tomatoes, typically used for making sauces, crushed tomatoes, or whole peeled fruit. This process involves a high-heat treatment to ensure food safety and allows the tomatoes to be shelf-stable for long periods.
Freezing
Freezing offers a simpler alternative, particularly for tomatoes destined for cooked applications. Whole or chopped tomatoes can be frozen, but thawing results in a soft, mushy texture due to cell wall rupture, making them best suited for soups, stews, and sauces.
Drying
Drying, either in a dehydrator or a low-temperature oven, concentrates the tomato’s flavor into intense, chewy pieces. Dried tomatoes are stored in airtight containers and provide a versatile ingredient that retains a significant portion of the fruit’s taste.