Refers to a type of food processing to improve a food's shelf life

refers to a type of food processing to improve a food’s shelf life, whereas involves techniques to help prevent food decay and contamination.

packaging refers to a type of food processing to improve a food’s shelf life, whereas food preservation involves techniques to help prevent food decay and contamination.

Explanation:

Food preservation is the process of treating or handling food to prevent the growth of microorganisms which cause spoilage without losing its nutritional value or taste.

Food packaging is known as the act of closing food so as to prevent tampering or contamination and also to improve the food's shelf life.