In addition to the preservatives above, there are still alternative types of preservatives obtained from fresh food ingredients such as garlic, sugar, tamarind These materials can prevent the proliferation of putrefactive microorganisms. Let’s identify each type of natural preservative one by one:
Table salt is a chemical compound Sodium chloride (NaCl). Kitchen salt is the main seasoning for every dish that functions to give a salty taste. In addition to enhancing the taste of salt, it also functions as a preservative. The nature of table salt is hygroscopic or absorbs water, so the presence of salt will cause microorganism cells to die from dehydration. Table salt can also inhibit and stop autolysis reactions which can kill bacteria in food.
The use of salt as a preservative is usually known as salting, as is done in the process of making salted fish, salted eggs, or pickled vegetables and fruit. How to use it is very simple, just add a high amount of salt to the food that will be preserved.
Granulated sugar is granules resembling crystals that are the result of heating and drying sugar cane or beet juice. Of course, you already know the form of granulated sugar, which is white granules composed of 99.9% pure saccharose. Apart from being sold in granular form, granulated sugar is also sold in powder form, popularly known as refined sugar.
The function of granulated sugar is usually added to food and drinks to give it a sweet taste. But apart from providing flavor, granulated sugar also functions as a preservative. As with salt, the nature of granulated sugar is hygroscopic or absorbs water so that the bacterial cells will become dehydrated and eventually die.
The use of sugar as a preservative, commonly known as sugar. Its use can be sprinkled or mixed and dissolved with food or drink ingredients that will be preserved. Examples of products preserved by sugar are sweets, jams, dodol, candies, syrups and jellies.
Vinegar is a fermented product of the acetobacter bacteria. There are many types of vinegar on the market, such as apple vinegar, black vinegar, palm vinegar and lime vinegar. Each of these vinegars is obtained from different fermented ingredients. There is another type of vinegar that is often used for cooking which is also called cooking vinegar. This type of vinegar is a synthetic/chemical vinegar with a very strong sour taste. Usually vinegar contains 98% acetic acid.
Apart from giving a sour taste to dishes and drinks, vinegar can also be used as a preservative. Products usually preserved in vinegar include pickles, kimchi, jelly and liqueurs. Its use is adjusted to the type of product being preserved. In addition to increasing shelf life, vinegar can also maintain color or prevent browning/browning reactions in fruits and vegetables. With the addition of vinegar, vegetables and fruit will retain their color more.
Garlic (Allium sativum) is a very popular spice in the kitchen. Its distinctive aroma and taste can give a delicious and fragrant taste to dishes. Aside from being a kitchen spice, garlic is very effective as a preservative. This is because garlic can inhibit the growth of yeast and bacteria. The allicin content in garlic is very effective in killing gram positive and gram negative bacteria. Garlic is also antimicrobial for E.coli, Shigella sonnei, Staphylococcus sureus and Aerobacter aerogenes. Another benefit is that it can reduce the number of aerobic bacteria, caliform and other microorganisms so that food ingredients added with garlic will last longer. It’s easy to use. Add garlic to chunks of meat or fish and store in the freezer. In this way meat or fish can last 20 days.
Apart from using natural food ingredients, food preservation can also be done by drying method. Drying is the most practical, safe, cheap and healthy way of preserving food ingredients. Almost all foodstuffs, both vegetables, fruit, nuts and meat can be preserved by drying. The goal is to reduce some of the water in food by 10-15% so that spoilage microorganisms cannot live.
The method can be drying using sunlight or oven heat. Dried foodstuffs such as sweet potatoes, vegetables and fruit are sliced thinly and then dried or baked in the oven at low temperatures (below 40 degrees Celsius) to dry. Furthermore, the food is stored in a cool, dry and tightly closed place. Dried food usually lasts up to 1 month.
Both natural and artificial food preservation methods will affect the quality of the nutrients contained, especially vitamins and minerals – nutrients that are easily damaged if preserved for a long time. Therefore, consuming fresh food is the best way to get optimal nutritional intake.