Saturday, 24 January 2015

Bio-Intensive Household Food Production - Chapter 7 - Handling Of Garden Produce

Conserving and safeguarding quality and freshness of garden produce


After harvest, the quality of fruits and vegetables cannot be improved but can only be maintained for a certain period of time. Therefore, proper care should start with harvesting.

Time of Harvesting

Fruit-bearing vegetables should be harvested as soon as the dew dries in the morning. Leafy vegetables, on the other hand, should be harvested during mid-morning, when leaves are flaccid.

Harvesting Practices

1. Use of picking pole (hook) for fruits - A bag or net should be provided to catch the fruit. This will prevent fruits from falling to the ground, protecting them from bruises.

Use of picking pole (hook) for fruits

2. Uprooting the entire plant - Vegetables like pechay and mustard are commonly harvested by uprooting the entire plant. This makes the vegetables dirty because of the soil that clings to moss. A sharp round-tipped knife should be used to cut the stem instead of uprooting. Open ends should be brushed out with chlorine to prevent entry of microorganisms which induce rotting.

Uprooting the entire plant

3. Digging tubers with spading fork - A marker or a label 30-cm from the center of the row should be put as guide so it will be easier for the harvester to determine where to dig. For ground creepers, vines should be lifted regularly during the growth period so that tuberous roots will be formed in rows.

Digging tubers with spading fork


Sorting and Trimming

1. Separate vegetables and fruits of different maturities. Ripe fruits placed with unripe ones will induce the latter to ripen faster, shortening their storage life. Baskets with dividers can be used to separate fruits of different maturities.

Separate vegetables and fruits of different maturities

2. Grade the harvested produce according to size/quality. Poor quality produce lowers the quality and price of the higher grade products. A separate package should be used for each grade.

3. Do not mix damaged produce with the sound ones. Damaged or injured portions of fruits and vegetables can hasten ripening of the products. Rotten commodities likewise cause the rotting of sound and clean ones. Produce damaged by insects, diseases and mechanical injuries should be put into separate containers. Those that are severely damaged should be composted.

Do not mix damaged produce with the sound ones

4. Cut fruit as close as possible to the stem-end with the use of clippers. Leaving a long peduncle attached to the fruit pricks the skin of other fruits, making them less attractive and providing entrance for microorganisms.

Cut fruit as close as possible to the stem-end

5. When trimming, retain 3-4 wrapper leaves to cover the head (in the case of cabbage, Chinese cabbage, head lettuce). Overtrimming (exposing head) just before packaging leaves no protection for the head to withstand further handling and transporting.

Packaging

1. Use containers that are neither too big nor too small to accommodate the harvest. Using very large containers is not advisable because handlers tend to drop heavy containers, resulting in bruised fruits and vegetables.

Use containers that are neither too big nor too small to accommodate the harvest

2. Put liners inside basket containers. Baskets used as containers for harvested fruits and vegetables should always be lined with suitable materials like banana leaves or newspapers. This will prevent the produce from getting in contact with rough surfaces.

Put liners inside basket containers


Transporting

1. For bulk transport without container:
Provide horizontal platform dividers and liners for trailers, jeepneys, etc., (for watermelon, melon, citrus and cabbage).

Provide horizontal platform

Arrange fruits crown-to-crown and base-to-base, with a cushion of banana leaves, rice stalks, etc., (for pineapple and bananas).

Arrange fruits crown-to-crown and base-to-base

2. Pack the produce carefully. Pliable packaging material cannot adequately protect the commodity. A 20-25 kg capacity crate lined with newsprint can be used for tomatoes and onions.

Pack the produce carefully

3. Provide space between the produce and canvas cover using a 30-cm wooden plank. Too compact stacking and use of snugly fitting canvas cover should be avoided to provide proper ventilation.

Provide space between the produce and canvas

4. Use only one type and one size of containers. Group containers according to size and type for easier stacking to minimize losses. Use small (20 kg) containers for mango, tomato, mandarin and citrus and a medium (40 kg) container for papaya and cucurbits. Each basket should have a hard cover.

Use only one type and one size of containers

5. If the baskets need to be protected from the rain or sun, use a light-colored canvas/plastic cover that radiates heat.

Use a light-colored canvas/plastic cover

6. Avoid "throw and catch system" during loading and unloading. For loading and unloading, at least three persons should be on hand to form a brigade.

Avoid "throw and catch system"

Source: ASEAN-PHTRC. 1981. Village Level Handling of Fruits and Vegetables; Traditional Practices and Technological Innovations. ASEAN-PHTRC Extenstion Bull. No. 1

Non-refrigerated storage


Vegetables and fruits have a short shelf life and have to be handled immediately after harvest. Leaving them unattended in one place will induce sprouting and rotting. Before storage, the commodity should be washed with chlorinated water, rinsed and air-dried.

Ways of Prolonging Shelf-life of Fruits and Vegetables

1. Sprinkling with water

Sprinkling water twice a day on some vegetables like winged beans (Psophocarpus tetragonolobus) and fruits like rambutan (Nephelium lappaceum) minimizes weight loss.

A disadvantage is that the free moisture hastens the growth and multiplication of microorganisms. Make sure that there is time for moisture to dry before sprinkling again.

Sprinkling with water

2. Wrapping with fresh leaves

Leaves such as banana (Muss a sapientum) and gabi (Colocasia esculenta) are good wrappers to keep a small amount of fruits and vegetables fresh for a few more days. Winged beans wrapped in fresh leaves can last for one-and-a-half to two weeks. Unwrapped ones only last for three days.

Banana leaves have to be slightly wilted over a fire to prevent them from cracking while in use. Leaves have to be changed before shrivelling and losing their protective property. Gabi leaves easily rot, so these should be changed before rotting occurs.

Wrapping with fresh leaves

3. Drip Coolers

A wet cloth can serve as a short-term storage for fruits and vegetables. One method is to cover the commodity with wet a cloth. Another method is to place a basin of water on top of a table and let a piece of cloth drop from the basin to the floor enclosing all the sides of the table. Beneath the table is the produce placed on a piece of banana leaf, newspaper or burlap. The cloth acts as wick, draining water from basin to the produce and forming a "curtain" around the produce.

Drip Coolers

4. Storage in Moist Sawdust

Wash produce to be stored, preferably with chlorox to achieve longer storage life. Use 1 liter of water with 1 tablespoon of chlorox. Air-dry to remove excess water. Use this solution to moisten the sawdust.

Use clean and pure sawdust. If it has been used before, sterilize it by sun-drying. Remove splinters to prevent them from injuring the commodities.

Moisten a kilo of sawdust with 1 liter of water. This can store 1 kilogram of tomatoes (Lycopersicon lycopersicum) or eggplants (Solanum melongena).

Mix sawdust and water thoroughly. Put it in a container or on clean floor in a cool, ventilated area. Bury the vegetables in the moist sawdust on a layer-by-layer arrangement. The first layer consists of sawdust, then a layer of vegetables, a cover of sawdust and so on. Each layer of vegetables should be left covered with medium-thick, moist sawdust.

Eggplant stored in this medium are good for more than a week under ordinary conditions.

Other commodities like potatoes (Solanum tuberosum), tomatoes, sweet potatoes (Ipomoea batatas) and mangoes (Mangifera indica) can be stored for short periods.

Storage in sawdust inhibits loss in weight as well as shrivelling. Sawdust, however, can be a source of infection if it comes in contact with any spoiled product.

Storage in sawdust is not applicable for leafy vegetables because it is difficult to remove sawdust particles from the leaves.

Storage in Moist Sawdust


5. Clamp storage

Storing produce in piled layers of straw is used by onion growers. This is known as clamp storage. Crops such as potatoes, sweet potato, cassava (Manihot esculenta) and other root crops are also stored in this manner, sometimes as a curing method. Curing is a wound-healing process to prevent entry of microorganisms.

Straw and grasses are common materials used. Layers of these materials are alternated with layers of produce until a convenient height is reached.

For onions (Alliurn cepa), a bamboo air duct (called breather) is provided to prolong storage life. This is made of longitudinally-cut bamboo slats tied together to form a tube with spaces between slats. It could also be a whole bamboo with nodes removed and hoses made along the sides at certain intervals. The breather is inserted vertically into the pile so that heat of respiration will escape. Protect the clamp against the rain, However, do not cover the clamp with plastic film, especially under full sunlight. to prevent rotting.

Clamp storage

6. Storage in Clay

Moistened clay jars are good places for storing some fruits and vegetables. The use of the clay jar is based on the fact that water evaporating from the area cools the immediate surroundings and increases the moisture in the air.

Vegetables like cabbages (Brassica oleracea var. capitata), eggplants, tomatoes, pole sitao (Vigna sesquipedalis) or winged bean can be stored in clay jars for a week. Clay jars can be moistened or kept cool in many ways:
a. One method is to pour water over the covered jar enough to wet it. This provides the water for evaporation. Repeat the process when the sides of jar dry. 
b. Another method is to seat a jar in a pan containing a small amount of water to provide a continuous supply of moisture that will seep up the sides of the jar and evaporate. Because free water accumulates at the bottom of the jar, a platform, made of banana stalks, sticks or any material that can support the commodities, should be provided to avoid the stored commodities from getting wet. 
c. Jars can also be buried halfway in moist sand or soil in a cool shady place to provide the necessary coolness. This method works well with mangoes and cabbages. Ants find the cool jars a nice place to live in, so watch out for their invasion. 
d. For big jars, there is a difficulty of getting water to rise from the bottom up the sides. This can be remedied by putting sacks or cloth over the covered clay jar and placing an inverted bottle of water on top, so the water drips slowly through the cloth or sack. 
Pour water over the covered jar enough to wet it


Seat a jar in a pan containing a small amount of water


Method works well with mangoes and cabbages


Putting sacks or cloth over the covered clay jar
Source: ASEAN-PHTRC. 1981. Village Level Handling of Fruits and Vegetables; Traditional Practices and Technological Innovations. ASEAN-PHTRC Extenstion Bull. No.1.
 Reference Source: International Institute of Rural Reconstruction