Current Approaches in Post-Harvest Management

 Introduction:

Post-harvest management is a system that covers all aspects from farm to fork. I.e. handling, storing, and transporting agricultural commodities after harvesting. Post-harvest importance increases from a past few years. Its establishments are necessary to reduce the post-harvest losses. Moreover, this management system strengthens the action chain that produces, transports, and processes food and all other related products.

Causes of losses:

The major causes are wrong postharvest practices and poor infrastructure for transportation, storage, cooling, processing, and marketing. Many farmers lack access to postharvest cooling equipment’s, refrigerated short-term storage and packing and loading facilities. Insufficient methodology on postharvest management and poor understanding of advanced postharvest technologies are the risk factors. This post-harvest management covers all the parameters harvest handling to post harvest storage including all chemical, mechanical and biochemical preservation techniques in it.

Comparison with old techniques:

Previously post-harvest technology only includes the processes done immediately after harvesting. including cooling, cleaning, sorting and packing and finally transportation. No additional preservation techniques. But now this system is given much more importance current approaches are given to increase the shelf life and maintains the quality. Thus, post-harvest technology largely determines final quality.

Current Approaches:

·         Controlled and modified atmosphere Packaging:

To improve and strengthen cool storage, controlled atmosphere (CA) and modified atmosphere packaging (MAP) are used. These techniques modify the environment in the surrounding and within they produce, either actively or passively. These will decrease the metabolic functions of climacteric fruits and vegetables and inhibits the enzymatic functions as well. Some factors are crucial for this storage time, relative humidity (RH), and ethylene concentration. These will greatly affect the shelf life of post-harvest commodity. This is a non-toxic technique and can be used on organic fruits and vegetables.

             Calcium Chloride (CaCl₂) Application:

Postharvest calcium chloride (CaCl₂) application is receiving a great attention in recent times due to its positive effects on shelf life as it will maintain the quality of many fruits and vegetables. It delays ripening and senescence process further reduces respiration, extends shelf life, maintains firmness, and reduces physiological disorders of many fruits and vegetables. This will be delayed softening and increased storage life by almost 3 months of fruits i.e. In fruits (Kiwi and loquat) and in vegetables (tomatoes). Moreover, this is cost effective technique as well. Required dosage of the salt in water used for precooling or cleaning of the fruits after harvesting.

             Edible coatings and films:

Edible coatings are used to prevent loss of firmness and moisture in horticulture commodity. These coatings will act as a barrier for moisture and gases during processing, handling and storage. They control maturation, development and respiratory rate. Edible coatings prevent oxidative browning and decrease growth of microorganism in fruits and vegetables. i.e. Tomato and Cucumber.

              New systems for cooling & temperature control:

The major effect of low temperature applications is to reduce the metabolic process to delay the quality loss and senescence of horticulture crops. Pre cooling is more beneficial for perishable foods. For this purpose, now a days mobile forced air-cooling tunnels and crates are used. These systems provide a shorter delivery time to market and decrease production costs as well. A wide range of pre-cooling systems (radiant cooling, evaporative cooling units, solar chillers, Cool-Bots) are used.

·         Ethylene Controlling Technologies:

In more high temperatures the delay in the ripening and senescence of fruits and vegetables is a curial factor for the preservation of quality characteristics of post-harvest fruits and vegetables. For this purpose, several active packaging systems are introduced based on absorbing or releasing compounds. These compounds interact with the product and control the ethylene production rates called scavenging ethylene or active Ethylene Remover. This approach is more beneficial on non-climacteric fruit. 1 MCP is used as a scavenger.

       Antimicrobial active systems:

Now a day’s antimicrobial active systems using various polysaccharide and protein-based biopolymers are developed which possess antimicrobial activity. These systems are important for fruits and vegetables producers. These active agents and coatings will slowly release fungicides and bactericides and prevent contamination this is known as “Bio Switch”. These are added in the packaging materials to extend shelf live by preventing bacterial growth and spoilage of post-harvest fruits and vegetables.

 Nanotechnologies:

These packaging systems has increased the safety of food. It has reduced material toxicity and control the flow of moisture and gases. Thus, has increased the shelf life of post-harvest commodity. These nanomaterials will interact with the food and provide active properties to the packaging system and environment. i.e. Biodegradable, bioplastics and active sachet are used for this purpose. Mostly used for agricultural products.

Conclusion:

Shelf life of the fruit can also be extended when appropriate postharvest handling practices and treatment methods are used. Thus, the postharvest quality status and shelf life of the fruits will depend on some postharvest handling practices and treatments carried out after harvest. Even though the quality of any fruit after harvest cannot be improved by the use of any postharvest handling practices or treatment methods, it can however be maintained. Postharvest handling practices like harvesting, precooling, cleaning or disinfecting, sorting and grading, packaging, storage, and transporting are important in maintaining quality and extending shelf life. Rather than this postharvest treatment methods like refrigeration, postharvest heat treatment, modified atmosphere packaging (MAP), and 1-methylcyclopropene (1-MCP), calcium chloride (CaCl2) application, Active Packaging and Edible coatings are also important for extending shelf life of post-harvest commodity.