Preharvest and Postharvest Factors PDF

PREHARVEST AND POSTHARVEST 2. Light duration and intensity affects: FACTORS ( Lesson 5)  Color – intense light leads to brighter peel, A. MATURITY but in mango, to...

PREHARVEST AND POSTHARVEST 2. Light duration and intensity affects: FACTORS ( Lesson 5)  Color – intense light leads to brighter peel, A. MATURITY but in mango, too much can cause scalding  The stage of maturity at which a crop is harvested have a significant impact on its postharvest  Nutrients – light causes vitamin C quality. Overripe or underripe produce may have accumulation shorter shelf lives or reduced nutritional value.  Composition – with light exposure, higher TSS, less acids, sweeter C. PEST AND DISEASE MANAGEMENT The presence of pests and diseases can lead to physical damage, rot and spoilage during storage and transportation. Practice fruit bagging, refrigeration and pre harvest crop protection. D. HANDLING PRACTICES Rough handling, overloading and improper packaging can contribute to physical damage and decay E. HARVESTING METHODS Use of sharp tools in harvesting produce can reduce damage to the skin of the produce, while manual picking can minimize the risk of bruising. Bruising causes higher respiration B. ENVIRONMENTAL CONDITIONS rate which can increase the changes of microorganism entry. This leads to faster 1. Temperature affects: decay and therefore shorter shelf life F. TIMING OF HARVEST  Color –synthesis of lycopene is best as Harvesting at the optimal time can help 16- 210C ensure the best possible quality of the  Texture – high temp of 24-260C produces produce. Late harvesting can lead to over- rough-skinned potatoes ripeness while early harvesting can lead to  Chemical composition – low temperature under-ripeness favors accumulation of starch and protein G. POST-HARVEST TREATMENTS in kamote Treatments applied to crops after harvest  Maturation rate- maturation falls in hot such as cleaning, grading and sorting can also months for mango affect their postharvest quality. These  Solar injury – high temp causes softening, treatments can remove physical damage, discoloration, collapse and drying reduce microbial growth and extend shelf life  Physiological disorders – high temperature causes feathering in asparagus; high temperature in soil causes potato black heart  Quality of products TRANSPORT AND STORAGE FOR FRUITS 3. Handling AND VEGETABLES (Lesson 6) Rough handling can cause physical damage such as bruising, which can lead to spoilage and A. TRANSPORT reduced shelflife. Transport must ensure high quality; the 4. Packaging causes of losses in transport include: Packaging that is too loose or too tight can cause mechanical damage because of impact, physical damage or create an environment that compression and vibration, and promotes spoilage. overheating due to closed vehicles 5. Ethylene without ventilation, close packing and stacking, lack of ventilation in packing and If ethylene-producing fruits and vegetables are exposure to direct sunlight during stored with ethylene sensitive fruits and transport. vegetables the latter can become overripe or spoil B. REFRIGERATION faster. Low temperature storage and mechanical 6. Time process of removing heat in an area are very important: Over time, fruits and vegetables can lose moisture, become overripe and develop off-flavors  to extend market season and off-odors.  avoid wastes of commodities, 7. Sanitation  limit the loss due to deterioration Are essential to prevent the growth of mold, bacteria and other pathogens that can lead to spoilage and foodborne illness. C. CONSIDERATIONS IN TRANSPORT AND STORAGE 1. Temperature Proper temperature control is critical to prevent spoilage and maintain quality. 2. Humidity High humidity can lead to the growth of mold and other pathogens, while low humidity can cause dehydration and loss of quality.