We all know that perishable crops do not last long, They have a very high moisture content, and are not to be kept for long after harvesting. They are much more susceptible to decay within a short period of time than grains, and they require stringent control of refrigeration, ventilation and humidity in order to remain edible for a period of time. These perishable crops include, fruits and vegetables; they vary in their storage requirements, but as a general rule, most fruits and vegetables should be stored between 5 and 9°c. Some perishable crops includes: Carrot: The recommended temperature for storing carrots is 32°F. Carrots will wilt and dry if not kept sufficiently moist. When properly handled, carrots can be stored for several months. Fresh market carrots generally are harvested before reaching full maturity. Avoid storing with ethylene producing commodities such as cantaloupes, tomatoes, and most fruits Cucumber: for 10 to 14 days when temperatures are maintained between 45 and 50°F. Temperatures below 45F for more than two days will cause chill damage. Chill injured cucumbers will develop water-soaked spots, pitting or tissue collapse. Extensive decay will develop when removed from low temperatures. Temperatures above 50F will cause the product to ripen rapidly and take on a yellow coloring after about 10 days. Ripening will be accelerated if cucumbers are stored with ethylene producing commodities. Adequate humidity is also important as cucumbers are subject to shriveling from loss of moisture. They are waxed to help prevent dehydration. Eggplant: Eggplants are very sensitive to extremes in temperature. They are held best at 45 to 50°F. Lower temperature will cause chill damage. Bruising is a common problem when careful handling is not employed. Decay will show up as dark brown spots on the surface. Lettuce: Recommended storage temperature is 32°F. Temperatures higher than 32F will shorten the shelf life of lettuce. Temperature must be maintained as close to 32°F as possible. A storage temperature of 38F will cut the storage life in half. However, lettuce also is damaged easily by freezing; therefore the storage room must be kept above the freezing point at 32°F. Respiration is also a problem with increased temperature. As the temperature rise, so does the respiration rate, which cuts storage life. Leaf lettuce respires at about twice the rate of head lettuce. If temperatures are kept below 35°F, russet spotting is generally kept under control. However, ethylene producing items such as apples, pears and cantaloupes can increase russet spotting. Head lettuce is more susceptible to the problem than other varieties, air circulation is important for lettuce. Lettuce should be stacked so maximum circulation is attained. Melon: Melons should be stored at 50°F. Melons are quickly affected by extremes of either very hot or very cold temperatures. Careful consideration should be given when storing melons with other commodities. Table 46 of the Appendix lists ethylene sensitive commodities. Ethylene gas produced by melons can cause certain vegetables to age and can cause butter to develop an off taste. Some characteristics to look for among the various melons comprise: Casaba Ripeness is indicated by a yellow rind color and slight softening at the blossom end (opposite the stem scar). The flesh should be soft, creamy white, sweet and juicy. Crenshaw Melons are round at the base, coming to a point at the stem end. They will have a gold and green rind that is smooth with no netting and little ribbing. When ripe they will show a softening of rind at the large end, have a golden skin and rich aroma. Honeydew These will have a creamy yellow color and velvety surface, but color will vary according to origin. If the outer surface is white with a greenish tint, it is unripe and lacking sugar content. A hard, smooth feel to the rind also indicates the lack of maturity. Mushroom: The best storage temperature is 32°F. Even under optimum conditions, mushrooms do not keep fresh more than one week after harvest. Under 32°F mushrooms will keep in prime condition for five days, for two days at a temperature of 40F and for one day if temperature is allowed to reach 50°F. Because of their high respiration rate, mushrooms require good air circulation. Mushrooms are comprised mainly of water (90%) and must be protected from dehydration. DO NOT package mushrooms in plastic bags. DO NOT wash mushrooms. Discard large (over 4″) over mature pods. Okra: Store at 40 to 45°F. Discard large, (over 4″) over mature pods. Onion, Bulb: Onions should be stored in a dry cool location. Cured onions can be stored at 32°F to retard sprouting. The best onion will be hard and firm. They should be stored dry. They may require additional drying after harvest in order to store well. 90°F with circulating air enhances drying and curing. Pepper : Under optimum conditions peppers should not be held for more than 5 to 7 days. The recommended temperature is 45 to 50°F. Peppers are subject to chill damage and pitting if temperatures fall below 45°F. Higher temperatures, above 50°F will encourage ripening or development of red coloring and rapid development of decay. Tomato: Tomatoes that are picked mature green and properly handled will ripen into a fully colored product with good flavor. Temperatures recommended for ripening fall between 50 and 70°F. Tomatoes are subject to chill damage at temperatures below 50F and lose flavor quickly. Care in handling is crucial. Bruising hastens spoilage and shortens the shelf life. DO NOT REFRIGERATE BELOW 50 DEGREES!!! Tomato quality is dependent upon proper harvesting and handling methods. Other examples includes: . Banana . Pineapple . Pumpkin . Spinach green . Cucumber etc. Handling techniques of perishable crops. closed vehicles without refrigeration should not be used to carry fresh produce except on very short journeys, such as local deliveries from farmers or wholesalers to nearby retailers; open-sided or half-boarded trucks can be fitted with a roof on a frame. The open sides can be fitted with canvas curtains which can be rolled up or moved aside in sections to allow loading or unloading at any point around the vehicle. Such curtains can protect the produce from the elements but still allow for ventilation. Where pilfering is a problem, the sides and rear of the truck must be enclosed in wire mesh; a second, white-painted roof can be fixed as a radiation shield 8 or 10 cm above the main roof; this will reflect the sun's heat and help to keep produce cool; for the ventilation of long-distance vehicles, more elaborate air intakes can be fitted in conjunction with louvres, to ensure a positive air flow through the load; refrigerated trucks or road, rail or sea containers may be used for long journeys, but the cost of such transport makes it uneconomical for small-scale operations. Mixing Commodities Some crops produce odours in storage while others emit volatile gases such as ethylene. Ethylene stimulates the ripening of many fruits and vegetables. This is negligible at low temperatures but may be a nuisance at higher temperatures. Consequently, even when two or three crops require the same storage conditions, it is not advisable to store them together. Products that emit ethylene include bananas, avocados, melons, tomatoes, apples, pears and all fleshy fruits. Lettuce, carrots and greens are damaged with stored with fruits or vegetables which produce ethylene. Even very small amounts can be harmful. It is recommended that onions, nuts, citrus fruits and potatoes each be stored separately. Sweating When fruits or vegetables are removed from a low temperature to a higher one, moisture often condenses from the air on the cool surface of the commodity. This is known as sweating; the higher the relative humidity of the outside air, the more marked it becomes. This is because the dew point of the air is at or above the temperature of the commodity. Sweating should be prevented or minimized whenever possible, particularly with onions and the more tender fruits, because it may favor decay. This does not mean that when products sweat after removal from a refrigerated room they will decay; it does mean that conditions are more favorable for decay than if the surfaces remain dry until consumed. Sweating can be prevented to some extent by allowing fruits and vegetables to warm gradually. Air movement over the product while it is warming is helpful in drying them. Harvesting and handling matters a lot when it comes to perishable crops, so one should be careful in harvesting them, and also, the right techniques should be used to avoid damaging of the crops which may lead to a huge loss.