Onion storage: Problems and solutions for India

Onion storage: Problems and solutions in India

India By Anil Chopra's Blog, Onion storage-Issues.

Onion prices have hit around Rs 70-80 a kg in retail during Dec 2010 which is equal to the average wage of $2 for 80% of the India. This is a cold fact. Part of the blame lie in our ancient onion storage systems and inability of all stakeholders in onion industry to establish modern onion storage systems in India.

Onion, being high in water content, is a delicate commodity to store and requires special procedure and parameters, giving rise to the concept of Onion cold storage. Onion is an important vegetable crop grown in India and forms a part of daily diet in almost all households throughout the year. But due to non-availability of appropriate post-harvest storage facilities, 25-30% of the total produced onions are wasted, which in terms of value amounts to Crores of rupees. Building up of the cold storage unit would minimize the waste up to the level of 3 to 4% that would in turn help the onion growers, and stabilize onion prices in market for all types of consumers.

Let's be honest and state the facts. For many people involved in the onion industry the complexity associated with properly storing onions is often overlooked.

Onion storage in the Netherlands during the fifties

Onion storage in India today, in bamboo huts

Onion storage in Sokoto, Nigeria

Monthly check, a total shrinkage during storage of 60%

The fact that we Indians can store onions from one harvest to the next in bamboo challis and tatties and maintain outstanding quality, albeit rising prices during non-harvesting season, is taken for granted. The reality is that 30% of onion is wasted during storage. Please download document penned by Director, National Research Centre for Onion and Garlic, Pune at following link and read page no 1.

The reality is that ability to hold onions in long-term storage and deliver quality product months after harvest is directly related to advances in ventilation system design and management. The ventilation system is really the key to maximizing profits from storage. Once the onions are harvested and placed in storage, the ventilation system is the only tool one has to interact with the crop. Anything that we do to the onions will occur using the ventilation system. For example, the processes of curing, cooling to holding temperature and dehumidification are all driven by the ventilation system and its components. In short, the ventilation system is our life-line to the onions.

Ventilation System Design

The ventilation system can be thought of like a car, in that it is composed of many components and control systems, each one with a specific job. Also like a car, each component must be the right size and the right part, or the car will not function properly. Modern onion ventilation systems are complex and composed of a variety of different components. These commonly include fans, fresh air doors, refrigeration equipment, burner systems, de-humidification equipment and control systems. In order for the ventilation system to operate effectively and promote onion quality, it must be properly deigned, properly installed, and properly controlled considering the product and environmental variables.

Proper ventilation system design is the foundation for the success of all onion storage efforts. In order for a ventilation system to function as desired, it must be properly designed and each component must be correctly specified and sized - in short customized as per the prevailing situation.

This is concept is the driving force behind the modern onion storage systems which are engineered and designed to conform to specific standards for airflow rate, fan selection, fresh air door sizing, plenum sizing, duct sizing and configuration, exhaust sizing, refrigeration system capacity, burner system capacity, and controls. The fact is that each component within the system will impact all of the others, and must be selected correctly.