This document discusses technologies for primary processing, storage, and valorization of onions. It outlines several challenges with current onion storage and processing techniques, including short storage durations of 3-4 months, lack of mechanization, and lack of value addition from excess or leftover onions. The document then describes several existing and potential methods to address these challenges, such as naturally ventilated storage structures, pre-harvest and post-harvest practices, and extracting compounds from onion waste for therapeutic purposes. The goal is to develop alternatives to refrigeration that require less skilled labor and resources while reducing storage losses and maintaining biochemical quality of onions.

1. Technologies for Primary Processing, Storage and
Valorization of Onions.
TOPIC
Presented by
Roll no. Names-
13 Soham Ghag
11 Kalpesh
7 Manish Bhalerao
Under the Guidance of
-Amruta Patil

2. Index
Abstract
Introduction
Problem statement
Applications
Methods
Future development
conclusion
Reference

3. Abstract
 In India, presently about 35 to 40 per cent of the onion is estimated
to be lost as postharvest losses during various operations including
handling and storage. Pre-harvest sprays of growth regulators viz.,
cycocel, ethylene compounds and fungicides play a crucial role in
enhancement of shelf life in onion. The curing techniques like neck
cut in onion bulbs and exposure to onion bulbs in gamma radiation
for storage are proved to be useful techniques in delaying sprouting
and their subsequent deterioration resulting in improved shelf life.
Packaging and storage techniques also influence the shelf life of
onion bulbs during storage.

4. Introduction
 Onion production in India is around 26.91 million MT from an area
of 16.28 million hectares (2020-2021). On average, India consumes
an estimated 1.3 million tonnes of onion every month, and to meet
this demand, the crop is grown in three seasons – Kharif (planted
between July-August and harvested in October-December); late
Kharif (planted between October-November and harvested in
January-March); and Rabi (planted between December-January and
harvested in MarchMay). So, the Rabi onion crop is the mainstay of
India. Normally, the price of the onion is lower during these months
due to greater supply. It is critical for India to successfully store rabi
onions to maintain its market supply during lean months.

5. Region-wise area, production and productivity of
onions in India

6. Problem statement
 The Onion storage grand challenge invites a proposal for developing ‘
Technologies for Primary Processing, Storage and Valorization of Onions’.
1. Durability and strength of storage structure
2. Low storage duration (as onions can be efficiently stored upto 3-4 months
3. Mechanization of onion harvesting
4. Reduction in processing time
5. Pre-harvesting stage
6. Valorization: Value addition and utilisation of unconsumed and excess onions

8. Methods
 Naturally ventilated structures (Kandha Chawl): Kandha Chawl
are the naturally ventilated structure, a scientific onion hut to
minimize the losses due to storage. In India, the onions are mostly
stored in such structures without any control of temperature and
relative humidity. The farmers construct different types of Kandha
Chawl based on the capacity required

9. Design

10. Applications
Pre-harvest care Post-harvest care
Selection of suitable material that prolongs the
storage time and capacity.
Proper field curing after harvest for 2-3 days
by covering the bulb with leaves. De-topping
the bulb by leaving 1-2 inch at the top of the
bulb
Proper irrigation from time to time without
any dry spell
Shade curing for 10-14 days
Application of recommended dose of
fertilizers at proper time. Excess application
of nitrogen is reported to increases the rotting
losses during storage
Sorting and grading before storage and
storage according to grades
Neck fall is an indicator of maturity stage
hence, best time to harvest is at 50% of neck
fall maturity.
Disinfection of storage structure before
loading of onions

11.  High temperature (Above 32°C) + Low RH (Less than 60%) = Weight loss
 Low temperature (0 - 2°C) + Low RH (Above 70%) = Sprouting
 High Temperature (Above 32°C) + High RH (Above 70%) = Rotting
 Temperature (25-30°C) + RH (60-65%) = Recommended OR
 Temperature (0-5°C) + RH (65-70%) = Recommended

12. Future Devlopment
 Must provide an alternative to refrigeration system
 Less skilled manpower requirement (by making the system user friendly)
 Material used in construction (local agri material, decided by participants as per
challenges)
 Loss reduction range must be: 20-25
 Cost should reduce

13. Parameter Present status Expected
output/improvement
Storage losses 20-30 % w/w 15-20%
Biochemical quality Biochemical analysis
(Pyruvic acid,
quercetin,
thoisulphonate values
etc.) after curing/
before storage
Non-significant/
minimal variation in
studied biochemical
parameters values
during storage
Suitable material and
scope for innovation/
improvement
To be decided by
participants as per
challenges

14. Conclution
 In this work, we focused our attention on the phenolic compounds present in
extracts from onion waste and their application for therapeutic purposes. The
extracts have been tested both in human colon cancer cells and in normal
enterocytes. Cancer studies showed that onion extracts are capable of decreasing
cell proliferation by arresting the cell cycle in S phase, showing a significant
increase in the p53 protein activity involved in this process. Likewise, death by the
intrinsic apoptosis of cells with the activation of caspase 3 was determined.

15. Refrance
 Model Scheme of onion storage
 ONION HARVESTING AND STIRAGE TECHNOLOGY – Dr. Jai Singh
 Deepak Aeloor,Neeta Patil ”A Survey On Odour Detection Sensor ”,International
Conference on Inventive Systems and Control ,2017)