This document outlines the key topics covered in the course HORTI 8 on post harvest physiology, handling, and storage of horticultural crops. The course covers:
1) The biological basis for postharvest practices and factors that affect metabolism, senescence, and quality in harvested crops.
2) Principles and applications of postharvest storage techniques like controlled atmosphere storage and methods to extend shelf-life using technologies like 1-MCP.
3) Aspects of deterioration in perishable products and introduction to postharvest facilities and the value of storage industries.
2. Physiology/Biochemistry
• Biological basis for postharvest practices,
emphasizing biotic and abiotic factors (e.g.,
maturity, temperature, humidity, gaseous
atmosphere, ethylene, gene action and
regulation, etc.) which affect metabolism,
senescence, stress-induced physiological
disorders and quality of harvested horticultural
products.
3. Postharvest Technology
• Principles, application and limitation of methods and
special techniques such as "common" and controlled
atmosphere storage, pre-cooling, and high humidity
storage; some modern instrumentation for assessing
quality such as for volatile analysis, packing line
technology; novel ethylene antagonists (e.g. 1-MCP),
phospholipase D inhibition technology etc., to extend
shelf-life of horticultural products.
4. Fundamental Nature of
Perishable Products
• Aspects of Deterioration;
• Introduction to Postharvest Facility;
• Value of Ontario Storage Industry
8. Maturation and Development
• Introduction and Terminology;
• Deciding Harvest Maturity;
• Fruit Development and Maturation
9. Metabolism of Harvested Products /
Metabolic Control Mechanisms
• Respiratory Metabolism – Overview;
• Stress in Harvested Products;
• Metabolic Control by Temperature;
• Alternative Respiration;
• Metabolite Channeling
10. Ethylene Physiology
• Biosynthesis and Measurement of Ethylene;
• Ethylene Biosynthesis;
• Role of Ethylene in Fruit Tissues;
• Ethylene, ACC, and the Climacteric;
• Exogenous Ethylene;
• Control of Ethylene by O2 & CO2;
• Stress, Auxins and Ethylene;
• Measurement of Ethylene;
• Properties of Ethylene;
• Developmental and Physiological Effects;
• Postharvest Uses of Ethylene;
• Sources of Ethylene;
• Undesirable Effects of Ethylene;
• Developmental Changes Induced by Ethylene;
• Cellular and Molecular Modes of Action;
• Ethylene Binding and Perception in Plants;
• 1-Methylcyclopropene (1-MCP);
• Ethylene and Biotechnology;
• Summary
11. Cooling Horticultural
Commodities
• Heat and Temperature;
• Need for Cooling;
• Cooling of Produce;
• Principles of Temperature Control of Postharvest Deterioration,
• Water relations
12. Gas Exchange and Movement
• Forces Driving Movement;
• Movement and Exchange of Gases;
• Gas Exchange & Atmospheric Stress
13. Oxidative Stress Physiology
• Active oxygen species;
• Effects of postharvest procedures on oxidative stress;
• Senescence and ethylene;
• Antioxidants;
• Mitochondrial electron transport – Alternate oxidase;
• Postharvest treatments to control oxidative stress,
• Physiological Disorders