Preservatives are usually either antimicrobial, which are described below and act against bacteria, molds or yeasts; or antioxidants, which slow the oxidation of fats and lipids, prevent spoilage and extend the life of baked products
You might probably ask yourself who wants to keep a yummy cake forever after reading the subheading definition of the Preservative. Well, Cakes have a shelf life of maximum 3-4 days if properly refrigerated. The quality of a Cake goes steadily downhill, beginning immediately. It may become stale and unappealing long before it has microbial spoilage problems. Baked goods, like all other foods, must be safe when consumed. At the same time, they need to be of good quality, delivering excellent taste and texture. Over the many years of producing such foods, the baking industry has relied on a multitude of ingredients as well as various tricks & methods to ensure safety and quality.
When discussing the safety of baked goods, we are primarily concerned with microbiological contamination as well as the danger of chemical contamination with natural toxins such as mycotoxins, which are usually controlled by close monitoring of these toxins in the flour supply. Bakers rely on suppliers to provide certificates of analysis confirming levels of such toxins.
Microbiological contamination, however, with the exception of spore-forming bacteria, mostly occurs after the baking process. For this reason, preservatives are used in baking formulations to ensure microbes are controlled and do not grow during the shelf life of the product. These subtle ingredients provide safety by controlling possible pathogens, and they ensure quality by preventing the growth of spoilage organisms. They could be natural extracts or synthetic chemicals.
However, the sound of a slice of cake hosting a myriad of chemicals is quite scary to some bakers. A few of them would prefer fairly light and natural additives, for example, a high sugar content that lowers water activity, Emulsifiers in commercial cakes help them keep softer for longer.
Some commonly used synthetic antimicrobial or preservatives in baked goods are Benzoates. They work best against fungi, yeast and some bacteria in foods that are acidic (low pH). Propionates are also antimicrobial, considered more natural because they are extracted from some fruits, grains and cheese. Some other natural antimicrobial include vinegar, raisin juice concentrates as well as some spices like cinnamon.
However, in case you are not baking a commercial cake (low shelf life say maximum 3-4 days), here are some tips for little or no preservative chemicals;
- Use less diary. Be it butter, milk, cheese, cream or condensed milk.
- Bake cakes with citric flavor like orange or lemon cakes (The trick is the high pH)
- Alcohol! Fruit cakes sometimes can stay up to a year, sounds like torture for the cake but adding booze to the recipe will not only keep it fresh but enhance the flavor by day.
- You could also avoid toppings or icing. Keep it cling-film wrapped or under a cake dome. To achieve maximum results using this technique, you must cool your cake completely before wrapping and preserving for days. If the cake is warm, the moisture will set in and give way to mold & fungus to grow.
- In juxtaposing Fondant Cakes with the other different decoration types, a substantial longevity is observed with the Fondant cakes compared to the latter.
Be sure to note however, in attempting to use these ingredients, either to preserve quality or ensure the safety of food products, we need to make sure they are permitted to be used in foods and the clients to whom the finished product is designated are okay with it. Hope this helps.