Food Preservation – Importance, Objectives, and Methods

Food preservation can be defined as the process to slow or stop food spoilage, its loss of nutritional value, quantity, and the edibility of food items. Food preservation methods are divided into two types – physical and chemical. Food preservation by preservatives is another way to preserve food. Let’s discuss food preservation methods and their importance here.

Food Preservation Definition

Food preservation is the method of preserving food to avoid food spoilage, food poisoning, and contamination of food by microorganisms.

Objectives of Food Preservation

The aims of food preservation are given below:

• To prevent the growth of micro-organisms.
• To minimize the spoilage of food items.
• To protect the taste, color, and nutritional value of food products.

Methods of Food Preservation

There are two methods of food preservation:

• Physical method
• Chemical method

Physical Method of Food Preservation

The different physical methods of food preservation are given below:

Freezing

This is the modern version of food preservation. This process does not kill the bacteria and yeast, but slows down the spoilage in the food. As yeast and bacteria both grow rapidly at a specific temperature (40F-140F), but lowering the temperature below 40F their reproductive and metabolic actions slow down. Food items such as sliced vegetables, berries, carrots, peas, and many more are preserved by this method.

Drying / Dehyhdration

It is an ancient method used for food preservation. In this, food items are dried decreasing the number of water and as a result, it stops bacterial growth. The drying process can be done by shelf dryers, household ovens, fluidized bed dryers, freeze-drying, spray drying, and commercial food dehydrators. In this method of food preservation, the weight of food products becomes lighter which makes products transportable. Food items such as fruits, vegetables, mushrooms, meats, and many more are preserved by this method.

Salting

It is the oldest method used for food preservation. In this method, salt removes the moisture from food and make an unfavorable environment for micro-organisms. There are very few bacteria that survive this excess high salt condition. This method can be used with other methods (dehydration, acidic solution) too. Food items such as vegetables, some fruits, fish, meats, and many more are preserved by this method.

Canning

This method became popular with the industrial revolution. In this method, food is preserved by removing the oxygen that is a basic need of micro-organisms. But still, some organisms can grow in absence of oxygen, so this method can be used with other methods (salting or with acid). Food items such as jams, juices, vegetables, fruits, and many more are preserved by this method.

Fermentation

This method is done under anaerobic conditions which involve a chemical change in food that use organic acids to convert micro-organisms. These anaerobic conditions occur in the absence of oxygen. This environment stimulates a microbial conversion of starches and sugars into alcohol, which is already a natural preservative. Food items such as cheese, yogurt, and many more can be preserved by this method.

Vacuum Packing

This is done by food vacuum machines. In this method, food items are packed in a bag and then removed all the air present in that bag, and then seal it tight. This method increases the shelf life of food items. Food items such as cereals, nuts, cheese, coffee, and many more can be preserved by this method.

Ionizing Radiation

Irradiation is used for eliminating parasites, reducing pathogenic bacteria, and extending the shelf life cycle of food items. In this method, food undergoes the exposal of ionizing energy which suppresses microbial growth. Food items such as fruits, vegetables, spices, and many more can be preserved by this method.

Chemicals Method of Food Preservation

This method of food preservation, include food preservatives or antimicrobials, although other synthetic preservatives like benzoates, propionates, and sorbates are also used.

Chemical Preservation

Modern industries are adopting the use of chemical preservatives. There are 3 types of chemical preservatives used for food preservation. Benzoates (such as sodium benzoate), sulfites (such as Sulphur dioxide), and nitrites(such as sodium nitrite). Before adding any chemical preservative, food goes through various processes like irradiation, cooking, and pasteurization in which ionizing radiations, heat, and high energy which kill bacteria and fungi that increase the shelf life of food. Food items such as cereals, jams, meat, juices, and many more can be preserved by these chemical preservatives.  

Importance of Food Preservation

The importance of food preservation is given below:

• It increases the food shelf life.
• Prevents the growth of microorganisms.
• It minimize the spoilage of food items.
• It allows us to taste a variety of food products in any season and in any area.
• It ensure the quality of food and prevent food poisoning
• Food products can be stored easily.

Conclusion – Food Preservation

In conclusion, food preservation plays a crucial role in extending the shelf life of food products and maintaining their quality. Through various techniques such as freezing, drying, salting, canning, fermentation, vacuum packing, and ionizing radiation, we can inhibit microbial growth and enzymatic activity, ultimately preventing food spoilage. These methods not only ensure food safety but also allow us to enjoy a diverse range of food products throughout the year. Also, both physical and chemical methods of preservation offer effective ways to meet the demands of modern food industries.

FAQs on Food Preservation

Name the Chemicals Used for Food Preservation? 

There are numerous chemicals used for food preservation, a few of them are-Sodium benzoate, Sulphur dioxide, Sodium nitrite, Sodium diacetate, Sodium lactate, sulfite, and Dehydroacetic acid.

What are the 5 Importance of Food Preservation?

Importance of food preservation includes extending shelf life, preventing spoilage, ensuring food safety, maintaining nutritional quality, and enabling year-round availability of diverse food options.

What are the Advantages of the Drying Food Preserving Method ?

Advantages of drying food preserving method are – stops bacterial growth, makes food items lighter and makes food easily transportable, and increase the shelf time of food products. 

Explain the Salting Method of Food Preservation ?

In this method, salt removes the moisture from food and make an unfavorable environment for micro-organisms. Food items such as vegetables, some fruits, fish, and meats are preserved by this method.

Explain the Fermentation Method of Food Preservation?

This method is done under anaerobic conditions which involve a chemical change in food that use organic acids to convert micro-organisms. Food items such as cheese, yogurt, and many more can be preserved by this method.