Devanshi Saxena
Fresh foods are a key to a healthy life, the reason our parents always stress the importance of eating well when our cravings for junk reached a threshold level. However, as our work life starts becoming more and more chaotic, the reliance on commercially packaged food increases, drawing us away from healthy eating options. Most of the times, we gorge on the elaborately packaged food without even devoting a moment to take into account the health hazards posed by the common preservatives and artificial additives in the food item.
What are food preservatives?
The primary use of food preservatives, as the name suggests, is in the preservation of both cooked and raw foods for a long period of time. Salt and spices have traditionally been the most preferred choice for food preservation like, in the case of pickles. However, with the recent advancements in packaging, machinery and chemical industry, it has become feasible to preserve all kinds of food items for prolonged periods, which would not have been possible with the use of traditional methods. Preservatives prevent the growth of harmful microbes and prevent any form of spoilage due to a chemical reaction, thus increasing the shelf-life of the food item. They retain the flavour, texture, edibility and nutritive value of the food item thereby preventing food poisoning. Preservatives can be natural or artificial (man-made). In spite of innumerable uses, preservatives pose as the source of major health hazards. It is mandatory for commercial products to specifically label and list the preservatives that are used in the given food item.
Classification of food preservatives
The food preservatives can be classified as natural (Class I) preservatives including sugar, vinegar, salt, spices, syrup, edible oil, and honey and chemical (Class II) preservatives including sorbates, nitrites, benzoates, sulfites, nitrates of potassium or sodium, glycerides, and glutamates. As per the guidelines issued by the global food standards, it is mandatory that only one type of Class II preservative be used in one food item.
These natural and chemical preservatives are further divided into three more types. These include antioxidants, which help in controlling the oxidation caused by oil and fat breakdown in the food. Examples of this are BHA, TBHQ, BHT and propyl gallate. Then there are antimicrobials, known to both delay and destroy the yeast and bacterial growth; for example, nitrates and nitrites controlling botulism in meat products, sulphur dioxide preventing degradation in wine, beer, and fruits, sorbates and benzoates controlling fungal growth in salads, cheese, jams, and pickles. Finally, we have anti-enzymatic preservatives, which help in blocking the enzymatic processes that lead to fruit ripening after harvesting. For example, citric acid is used to prevent the browning caused by the action of phenolase enzyme in chopped fruit pieces.
Negative effects of commonly used preservatives
Every day, we conveniently overlook the health risks posed by the high concentration of preservatives and additives in our food. A glimpse into the possible health hazards associated with the use of these chemical preservatives may help us make better food choices.
Sodium nitrite as a preservative is commonly added to processed meats and fish to prevent the growth of botulism-causing bacteria. However, a diet that abounds in sodium nitrite concentration may lead to a condition called methemoglobinemia, leading to inhibited oxygen transportation to the body cells. It can also lead to gastrointestinal and brain cancer while increasing the risk of Type 1 Diabetes.
Potassium Bromate, which is added to bread as a flour enhancer, breaks down into bromide on heating. This, when consumed in excess, inhibits the iodine metabolism and is regarded as a possible carcinogenic compound.
Sodium benzoate is often used as a preservative in soft drinks, juices, cereals, and meats. It is known to kill bacteria in acidic conditions. Several studies have linked sodium benzoate to headaches, stomach upsets, asthma attacks and hyperactivity in children.
Food colouring along with preservatives
Colouring agents include colour stabilisers, fixatives and retention agents. It includes synthetic colours, synthesised colours that also occur naturally and other colours from natural sources. Colouring agents do not contribute in enriching the nutritional value of food but are frequently used to restore the natural colour lost during food processing or to give an enhanced appearance as per the expectations, to the finished product.
For example, one of the best known and most widespread red pigment is bixin, derived from the seed coat of Bixa Orellana. The Annatto dye obtained from it is used as a colouring matter in butter, cheese, margarine, and other foods. Saffron and turmeric are natural food colouring agents used in curries, some meat products, and salad dressings.
Safety evaluation of food additives
As the general principle states, “All things are poisons; nothing is without poison; only the dose determines whether there is a harmful effect“. An excessively unbalanced consumption will surely come with a set of malignant health risks while a controlled, safe limit is the solution to evade the major health risks associated with synthetic compounds. It is for this purpose that an Allowable/Acceptable Daily Intake (ADI) index has been formulated by the food regulation authorities who analyse the test data on food additives, set the food safety standards and ensure that the food safety standards are being adhered to.
Prevention strategy and alternative methods
The Food Safety and Standards Authority of India (FSSAI), under the Health Ministry, has laid down several regulations for the use of preservatives. It has fixed the maximum limit for the use of additives in various food items to ensure that the daily intake does not exceed the acceptable safe limit. Several measures have been taken to strengthen the quality standards of packaged food. There are additional review rules to monitor the caffeine content, metal contaminants and other residues in food products.
While it is always advisable to prefer fresh food over packaged items, there are better natural alternatives to synthetic additives when it comes to following healthy food choices. Making them a part of your pantry is the best way to deal with the hassle of artificial preservatives. They help in keeping the leftovers fresh, prevent spoilage and bacterial growth. For example, cloves have antioxidant properties and prevent fungal and bacterial growth. Lemons being a natural source of the citric acid act as an antibacterial preservative. Garlic and vinegar also have anti-microbial properties.
Although there are many synthetic food preservatives that are considered to be safe, overuse of even these preservatives can be harmful. Hence, using natural preservatives, if not fresh foods is the best solution to avoid any harmful side effects. It is also important to follow the rules for handling, cooking and preserving the foodstuff according to the labels to ensure food safety.