Indeed, you can even purchase tanks of gases like nitrogen and carbon dioxide at welding supply businesses and use them at home (just remember to buy a pressure regulator). I used to make hundreds of liter bottles of seltzer water for Marie using a medium sized tank of carbon dioxide gas with a pressure regulator and simple tap water, for about six cents per bottle. My labor was about 30 seconds per bottle. See the recipe for lemon-lime soda in this book to learn how to do all of this process.
The advent of high quality vacuum sealing machines for home use, freezers that maintain temperatures of 0ļF, and such mechanical devices as high quality meat slicers and food processors and top quality electric mixers and blenders, and a myriad of attachments and accessories, make this environment both more complicated and also more rewarding. Donít feel overwhelmed. Get them one at a time and take your time to learn how to use each one well. These many products increase your freedom to do things that canít easily be done in lesser kitchens, indeed in time your concept of how to use your kitchen and various food products will change substantially.
It is important to realize that commercial food processors have access to chemical preservatives that, regardless of our opinions regarding some of those chemicals, are not all available to consumers, due primarily to government regulations. An example of what you can buy is sodium benzoate, a common preservative in pickled products, sauces and dressings. The opposite is true for sodium nitrite and chemicals like calcium disodium EDTA. You will likely never see yet other chemicals like sodium bisulfite unless you happen to make wine and have a supply store near you with all the specialty wine chemicals, some of which can be used in other foods. Unavailability of certain chemicals does limit what we can choose to do safely and/or with optimal results in food preservation. The home chef must prepare and use many fresh foods within a few days that do not lend themselves to long term refrigerated storage, for lack of chemical preservatives. Conversely, a number of recipes use products that already contain chemical preservatives and they, along with acidic and/or salty recipe compositions permit longer refrigerated food storage. And pasteurization of the product, while not as dependable as canning, is a great way to extend the shelf life of lots of products you make and then package and refrigerate. An example of builtin preservation chemicals in some of the ingredients, combined with heat for sterility, is when you make homemade barbecue sauce that has been simmered and immediately sealed in a sterile jar.
The knowledge gained in using the above mentioned devices and methods of food handling supports the home chef with choices in food preparation and preservation that would have amazed our grandparents. And even chemical preservatives can be obtained in special circumstances, like sodium nitrate and sodium nitrite in pre-measured mixes for making home cured meats like pastrami. For that matter the natural acidity of some foods like tomatoes and citrus fruits, and the use of acidic products like vinegars, allow you fairly long food storage, refrigerated, without other chemical preservatives.