1.0 Introduction

This training module will be used for training Field Staff (TOT), who will then train the farmers. The training will at both levels be interactive and will use live specimens for demonstration. The training will therefore be based near a farm or at least the trainees will be able to visit a farm of the produce at the period when harvesting and post-harvest handling are being carried out for practical demonstration.

Gooseberries belong to the class of small fruits. Because of their small surface area to volume ratio, they very easily deteriorate after harvest through water loss and respiration. Because of their high-water content, they also easily deteriorate through microbial growth (due to high acidity mainly by fungi), consumption by higher animals like insect pests and rodents and physical injury. Proper post-harvest handling is therefore essential to maintain the quality of the fresh fruits.  The fruits must be harvested at optimum maturity (firm ripe from greenish yellow color to red) using methods that prevent physical injury and fruit contamination with debris, soil and microorganisms. The important post-harvest handling processes include sorting and grading, cleaning, disinfection, packaging and storage.

Both quantitative and qualitative losses occur in horticultural commodities between harvest and consumption. Qualitative losses, such as those in edibility, nutritional quality, caloric value, and consumer acceptability of fresh produce, are much more difficult to assess than are quantitative losses. Quality standards, consumer preferences and purchasing power vary greatly across countries and cultures and these differences influence marketability and the magnitude of post-harvest losses.

This module therefore intends to help the horticulture smallholder farmers achieve the following:

1. Gain knowledge to identify the maturity at harvest
2. Gain knowledge of the available harvesting methods to choose the ones that maintain fruit quality and minimize quality loss.
3. To gain knowledge and practice of the post-harvest handling practices including sorting and grading, cleaning and disinfection, and packaging that maintain quality in storage or the market.
4. Gain knowledge and practice prudent storage that reduces loss in storage.

2.0 Pre-harvest considerations

Cape gooseberry fruit is harvested 60 to 100 days after flowering or when the calyx has a tan (dry- grass) or light-brown color, or fruit drop down. The fruit should be firm ripe. The harvest season lasts for 3 to 4 months. Because of bimodal rainfall in Kenya, gooseberries can be harvested twice a year. The first season is from July to September and the second one from December to March. The fruit is ready to harvest 55 days after anthesis or when the calyx is dry which is when the fruit ripens and becomes sweet.

The color of the fruit also changes to yellow-orange when ripe. Gooseberry may also be harvested when the fruit has a green-yellow color and allowed to ripen. Fruit is harvested every 2 to 3 weeks. Gooseberries will continue bearing for 2 years if maintained well. The first crop will come the second season after planting. Gooseberries for cooking should be harvested slightly under ripe while those for fresh eating or desserts should be allowed to ripen fully on the bush. Gooseberries develop full flavor only when they are left to ripen on the bush. Ripe gooseberries will be full-colored.

3.0 Harvesting

The fruits are usually harvested when the husk or calyx has turned dry and light yellow in color. Remove of the husk reveals a yellow-amber fleshy fruit. The fruits are harvested by manually picking them from the plants by hand every 2 to 3 weeks, although some growers prefer to shake the plants and gather the fallen fruits from the ground in order to obtain those of more uniform maturity. This method could however lead to heavy harvest losses because of bruising when the fruits fall directly on the ground, contamination with dirt and microorganisms and falling of immature fruits.

In rainy or dewy weather, the fruit is not picked until the plants are dry. Berries that are wet should be dried in the sun for a short time. The harvested fruits are picked in traditional baskets, plastic buckets, etc. Harvested fruits should be put under shade or protected from direct sunshine. The harvest of one plant will last over five to six weeks. Harvest thorny-stemmed gooseberries by holding a branch up with one gloved hand and picking or sliding your other gloved hand down the stem letting berries fall into a container. It’s best to wear heavy leather gloves as the thorns are prickly.

To take advantage of the cool morning temperatures, the fruits should be harvested early in the morning and transferred to a shaded area for subsequent handling. This is to avoid accumulation of field heat and rise in temperature which shortens the storage green life of the fruits. The fruits are shelled by removing the husk/calyx and the stem (plug), then washed with water containing chlorine or metabisuklphite (500 – 600ppm chlorine or 300-500ppm sodium/potassium metabisulphite) to disinfect.

4.0 Post harvest handling

4.1 Sorting and grading

Sorting is done to separate poor produce from good produce. Sorting removes the blemished, diseased, unripe, overripe, misshapen and undersize berries. The marketable produce is graded according to the following criteria:

Maturity/ripeness

Size

Shape

Color/ripeness

Weight

Freedom from defects such as insect, disease, and mechanical damage

4.2 Packaging

The fruits must be packaged in terms of the grade as this helps with pricing. Gooseberries must be packed in such a way as to protect the produce properly. The materials used inside the package must be new, clean, and of a quality such as to avoid causing any external or internal damage to the produce. The use of materials, particularly of paper or stamps bearing trade specifications is allowed, provided the printing or labelling has been done with non-toxic ink or glue. For the retail market, the fruits could be packaged in paper or plastic trays with a transparent cover for ease of display.

4.3 Storage

Gooseberry should be harvested using plastic crates that are clean and dry. The fruit should be stored under shade in a fully aerated room. It is recommended not to remove the calyx until ready for use. Fruits with intact calyx have a shelf-life of 4 to 6 weeks at room temperature in a well aerated room. For prolonged storage, gooseberry fruits can be stored at 2-4°C for 4 to 5 months.

Before packaging and storage, the graded fruits should be dipped in chlorine water (see concentrations recommended for vegetable and fruits treatment with water guard or Milton’s solution) then drip dried in a cool place. A dip of 0.2% sodium or potassium metabisulfite can also be used. The dip is to get rid of the microorganisms on the fruit surface and also helps to clean the fruits.  A two-minute dip with gentle agitation will be adequate

4.4 Transport

Care must be taken that trucks are not overloaded or the bottom layers of produce are crushed. Generally, the produce should be covered with a sheet to prevent frosting or desiccation, but on warmer days, when sweating and heating might occur, the sheet should be left off. The loading into the transport vehicle should be in such a manner as to avoid compaction damage. Crates are good for this purpose because they can be packed as vertical layers without the fruits compacting between them.

5.0 Causes and controls for post-harvest loss in gooseberries

Damage by insects and birds - protective packaging.

Rotting and fermentation due to microbial growth – disinfection.

Loss of water leading to shriveling and loss of weight - packaging, cool storage at RH>8%.

Respiration leading to loss of sugar and sweetness – packaging to exclude air and cool storage.

Physical damage during harvesting and shelling and due to materials handling in the store and transportation – handle with care.

Physiological damage in refrigerated storage – store at higher than the critical temperatures for development of chilling injury.

6.0 Post-Harvest diseases & pests

I.Birds

 Birds, especially pigeons, can cause an array of problems including eating seedlings, buds, leaves, fruit and vegetables.

Figure1 Purple ripe gooseberries

Remedy: Protect the plants from birds by covering them with netting or fleece. Scarecrows and bird-scaring mechanisms work for a while, but the most reliable method of protection is to cover plants with horticultural fleece or mesh.

II.Fruit Borer caused by Deudorix Isocrates