Each fermentation category has different food ingredients and requires different starters to begin fermentation. A starter contains some of the good bacteria you want in that food and helps get the fermentation off to a good start. Some ingredients are common to most fermentation recipes, such as the following.
Water for fermentation
Water is the most important ingredient used in fermenting. It may seem like you can just turn on your tap and get clean water to use, but with fermenting foods, it isn't that easy. Many things in water can affect how well foods ferment and can also affect the taste.
Municipal water treatment plants add chlorine or chloramine to water supplies to kill harmful bacteria, and these products can also kill the friendly microbes you want to attract. Though chlorine dissipates into the air if it sits a day or two and can be boiled out, these practices don't get rid of chloramine, which is the most popular water treatment these days.
To remove chloramines from tap water, it must pass through a good microfiltration process, an activated carbon filter, or a UV light filter. Reverse osmosis and other filtration methods don't work. You can also use sodium thiosulfate and a product called Campden tablets to remove both chlorine and chloramines. You can buy these tablets at brewing and wine-making supply stores.
If you have access to well water, be aware that well water varies tremendously as to what it contains. You've probably had the well tested to see whether it has bacterial contamination, nitrates, or arsenic, but well water (or spring water) often has dissolved minerals like sulfur and iron that can affect the taste and quality of fermented foods without being a health hazard to those who drink it.
If your well has a high mineral content (hard water) or a high salt content, two common well problems, the water may not be suitable to use for fermenting.
If you have a filter that removes most minerals, your well water may be suitable for fermenting, but water that is run through common water softeners may not produce the best water for fermenting because softeners often leave salt or other chemical traces in water.
Soft water is alkaline, which is the opposite of the acidic conditions needed in fermentation, and the good microbes need to work harder to produce results. You can try using well water, especially if you like its taste, and see how things turn out. If you have a tap that isn't connected to a water softener, draw water from that and run it through a charcoal filter for use in fermenting.
Probably the best water to use in home fermentation and brewing is distilled water. It's inexpensive and available almost everywhere. Unless you're making gallons of fermented produce or brewing large quantities of beer, this is a good choice for home fermenting.
When buying bottled water, make sure you get distilled water, not just water, often labeled spring water. Most bottled water is just someone's tap water and may contain chlorine and chloramines, just like your tap water.
Salt used in food fermenting
Common table salt has iodine added, as well as some chemicals to keep it from clumping, and it isn't the best salt for fermenting. But most stores sell kosher, canning, and sea salt, and all those are fine for your fermenting projects.
When a recipe calls for salt, don't reduce or increase the amount unless the recipe tells you it's okay to do so. In fermenting, salt is often important for food safety, reduces bad microbes, and helps preserve food. Never use salt substitutes or reduced-sodium products in fermenting unless your recipe gives instructions for it. These products may prevent fermentation and compromise food safety.
A combination of salt and water is called brine. Brine is often used in fermenting recipes.
Fermenting foods with sweeteners
Almost all fermenting recipes call for some sweetener, usually sugar. Sugar helps feed the good microbes as they get started fermenting your food. When a recipe calls for sugar, you can use organic raw sugar or regular table sugar.
When using white sugar, look for cane sugar specifically. If the package doesn't say cane sugar, it's beet root sugar, which is a genetically modified product.
If the recipe calls for honey as a sweetener, make sure you use pure honey — preferably local, raw honey. Store-bought honey is fine as a second choice, although recent studies have shown that up to 75 percent of store honey is no longer honey because it has been purified to remove the pollen that makes it special.
If other sweeteners, such as agave syrup, are called for in your recipe, use them, because substituting other sweeteners may not give your fermented food recipe the intended results.
Don't use sugar substitutes or half sugar-half substitute products in a fermenting recipe. These don't feed the good microbes and may also contribute to an off flavor in food. After food is through fermenting, if you feel it needs additional sweetener to taste good, you can add a sugar substitute.