Lecture 1 Flashcards
describe harvesting
- separating from the mother plant
- beginning of the deteriorate process
what happens to quality after the crop is harvested?
what is an exception?
the longer the crop awaits before being used, the lower will be the quality
except some fruits which have optimal quality after a ripening period
what are main differences between characteristics of durables and perishables?
durables
- low moisture content
- small unit size
- low resp rate
- low generation of heat
- hard texture (not easily damaged)
- stable( natural shelf life of several years)
- losses mainly caused by external agents (eg. molds, insects, rodents)
perishables
- high moisture content
- large unit size
- high resp rate
- high heat production
- soft texture (easily damaged)
- perishable (short natural shelf life)
- losses caused by external agents and endogenous factors
what is the moisture content of durables?
low (10-15%)
what is the moisture content of perishables?
high (50-90%)
compare the unit sizes of durables and perishable
durables: small unit size (less than 1g)
perishables: large unit size (5g to 5kg)
compare the respiration rate and heat generation of durables and perishables?
D: low resp rate; low heat generation
P: high resp rate, high heat prod
compare the texture of durables and perishables
D: hard texture, not easily damaged
P: soft texture, easily damaged
compare the shelf life of durables and perishables
D: stable; natural shelf life of several years
P: natural shelf life of a few days to months
what mostly causes losses in durables?
external agents (molds, insects, rodents)
what mostly causes losses in perishables?
external agents and endogenous factors (respiration, senescence, sprouting)
what are average estimated losses of produce?
why is this?
24-40%
because produce loss is inevitable
what are ways to counteract produce loss?
grow more food by:
- cultivating more land
- intensifying agricultural production
- using high density planting
- using growth promoters
- using new fertilizers
- GM foods
what are advantages of minimizing post-harvest losses?
- nutritional (remaining food is usually more nutritious)
- economic
- excessive food loss creates the initiative to produce more food due to fear of greater losses
- environmentally friendly
- consumer satisfaction
- increasing food supply without using more resources (land, energy, water, capital)
describe the economic incentive to decreasing post-harvest losses
- wastage represents an economic loss
- loss increases as the food moves down the food pipeline (cost of food and of handling, transportation, storage, etc…