Food preservation dates back to prehistoric times with tried-and-true methods like drying, freezing, and fermentation. Out of necessity, our early ancestors had to find a way to preserve their bounty throughout the winter months when food was less plentiful. Thus, in frozen climates, they froze meat on ice, and in tropical climates, they dried foods using sun and wind. While we don’t have to rely on the elements anymore to prevent our food from spoiling, the basis of ancient practices are still pertinent today. Today, we have numerous ways to increase the shelf life of our food including blast chilling, refrigeration, and sous vide cooking. Moreover, technological advances have made huge contributions to the efficacy of food preservation methods, meaning that now after our food has been harvested, it lasts longer, contains more nutrients, and tastes better.
While refrigeration and freezing are perhaps the most obvious forms of food preservation today, there are several modern technologies revolutionizing this type of food preservation. Refrigeration reduces food spoilage by dramatically slowing bacterial growth, which in a favorable environment can cause foodborne illness. The “Danger Zone,” a temperature zone between 40° F and 140° F, sees the most rapid growth of bacteria. Thus, a refrigerator should always be set at 40° F or below to protect foods. Krystina Holford of Sub-Zero explains that above all else, “maintaining temperature control is paramount to food preservation, which is why Sub-Zero refrigerators and freezers hold to a single degree, staying within a ½ degree in either direction.” Air purification is also extremely important in refrigeration, as ethylene gas continues to be produced after plants are harvested, impacting ripening, aging, and eventually, spoiling. In addition, “some fruits, like apples and mangos, produce greater amounts of ethylene, whereas foods like lettuce and bananas are sensitive to the gas and should not be mixed with heavy producers” states Krystina. A pro tip for extending the life of your produce: store your ethylene producing foods, like apples and bananas, separate from your low ethylene sensitive foods, like lettuce, peppers, and broccoli. Ultimately, temperature control, air purification, and humidity control are the three most important factors in ensuring that your food lasts longer and tastes better.
Sous vide, meaning “under vacuum” in French, is a cooking technique that involves vacuum-sealing food in plastic and then cooking it in a precisely regulated water bath. Vacuum sealing slows down the ageing, deterioration, and oxidation processes in food, naturally preserving its quality and nutrient content. However, not all vacuum sealers are created equally. The Irinox Zero™, an Italian made vacuum-sealer, is the first ever built-in machine that can reach a vacuum close to absolute zero. The Zero also boasts 6 different programs —gentle vacuum, preservation vacuum, extreme vacuum, meat ageing, marinating, and liquids— to make all your cooking dreams come true.
Larry Welch of Irinox comments on the versatility of this machine, explaining that “you can tailor the vacuum to fit with what you are trying to store without the fear of squeezing the products you are trying to seal. Think of the different needs like sealing bay leaves vs. frozen strawberries; you don’t want to crush the bay leaves but frozen strawberries can handle extreme pressure.” Ultimately, cooking sous vide has numerous benefits for food preservation, including improving the shelf life of food, enhancing taste and texture, maintaining nutrition, and preserving food safety. If you’re interested in learning more about a vacuum sealer from PIRCH, check out brands like Gaggenau, Sub-Zero, Fisher & Paykel, and Miele.
Blast chilling, also known as blast or flash freezing, quickly lowers the temperature of food. By very rapidly blowing forced cooled air over food, this method can even freeze warm or hot foods, in addition to room temperature food. This rapid freezing process ensures a reduction in the number of ice crystals present, which contributes heavily to the preservation of the food’s taste and texture. In contrast, most freezers cannot guarantee to freeze items at high speeds while keeping the frozen item’s original texture and flavor. Blast Chilling ultimately does what freezing cannot do, preserving the ingredient’s smell, freshness, color and nutrients for a short period of time while still keeping the product intact. The Irinox Freddy™ is the first blast chiller made for home use, with a variety of features for the cooking enthusiast. Blast chilling “reduces bacteria growth, oxidation, evaporation, and over cooking,” says Larry Welch of Irinox, and can change the game for leftovers. With “blast chilling, you can store leftovers in the fridge for twice as long as usual, and they will taste nearly as fresh as when they were originally served,” says Larry.
Food smoking is a technique that began thousands of years ago when humans first discovered fire and is a method of drying that also imparts flavor to the food using wood or charcoal. There are a wide range of foods that can be smoked, including vegetables, dairy products, pork, poultry, beef, and fish. The sky is the limit with this food preservation technique! For home cooks wanting a modern smoking experience, there are numerous outdoor appliances that fit the bill like the Konnected Joe Charcoal Grill, Coyote Kamado Grill, Kalamazoo Shokunin Kamado Grill, Alfresco ALXE Grill, and Kalamazoo Hybrid Grill.
With smoking, there are two distinct methods: hot smoking and cold smoking. In hot smoking, food is placed alongside the fire that produces the smoke and is kept at around 320° F. This method is most used, as food is smoked and cooked simultaneously. With cold smoking, food is placed in a chamber or box and smoke is pumped through the chamber for a period of around 12- 48 hours, all while between a temperature of 65 – 85° F. It is important to note that after cold smoking, the food is still raw, but can last months without being unrefrigerated in the correct environment. This is due to the curing process that precedes cold smoking, where salt is added to meat or fish to extract moisture and inhibit bacterial growth.
Dehydrating is the ultimate low and slow preservation method, where food is dried for several hours at a temperature of 165° F or below. Through low heat and steady airflow, dehydrating removes enough moisture from food through evaporation to inhibit the growth of bacteria, yeast, and mold. It is often used to extend the shelf-life of ingredients, for instance dehydrating fresh tomatoes after a summer harvest makes them edible all year round. Many confuse dehydrating with sun drying, a type of drying that relies on the heat of the sun to evaporate moisture from your food. However, this method relies on strong sunlight and temperatures above 98° F to work best. In addition, sun drying tends to be a lengthy process, taking anywhere from 4 to 20 hours for your food to be completely dry. Thus, dehydrating is a fabulous replacement for sun drying that you can try any time of year!
In terms of appliances, most convection and steam ovens nowadays can dehydrate any kind of food, like fruits, vegetables, and meats. To dehydrate, you will need to set your oven to a temperature of 165° F or less, as higher temperatures will cook food instead of drying it. Poultry, meat, and seafood will dehydrate at higher temperatures, while fruit, grains, vegetables, and legumes require gentler heat. There are also various outdoor appliances that can dehydrate foods, such as the Konnected Joe Charcoal Grill, Coyote Kamado Grill, Kalamazoo Shokunin Kamado Grill, and Kalamazoo Smoker Cabinet. After the dehydration process, foods should be stored in an airtight container and placed in a cool, dry area to prolong their shelf-life. Using this method, dried foods can last a few months to several years, versus a few days to a few weeks. Benefits of dehydration include better nutrient preservation, space saving, and a hands-off approach to drying.
No matter what your level of kitchen expertise, there is a food preservation method out there for everybody! Although our modern preservation methods are much more automated than they used to be, the art of home preservation is still a worthwhile skill to learn to get the most out of your food and reduce food waste. Modern food preservation methods simply add more tools to your toolbox, especially if you are already fond of traditional preservation methods like canning or fermenting.
Want to learn more about our appliance offerings? Visit a PIRCH showroom near you and speak with one of our knowledgeable sales consultants.