Fruit handling

Fruit Handling and Decay Control Techniques Affecting Quality... 

Oil from fruit pulps (e.g., palm) are processed in the same way. To obtain good qualities (low color and ffa), it is necessary to otganize the whole procedure well, starting with the harvest, fast fruit handling, prompt sterilization and finally, work up procedures. Today, producers are able to offer high quality reliably. 

The most severe environmental problem of fruit and vegetable processors is the potential for water poUution if the liquid wastes are not handled properly. Cooking can cause odors, which are usually controlled by using furnaces as afterburners. 

The most significant application of reverse osmosis has been in the field of desalination to produce drinking water. Other important apphcations include the treatment of industrial waste water, concentration of fruit juices, and concentration of weak solutions such as aqueous ethanol [3-6]. The rest of the chapter will focus almost entirely on semi-permeable membranes used for reverse osmosis based applications. We chose this focus in view of the importance of reverse osmosis as a rather efficient separation technique for separating a wide range of solutions, especially very dilute solutions—which are usually notoriously difficult to handle using conventional techniques such as distillation. 

Fruit juices, meat products, milk and milk products, fish and most vegetables, in which tin is likely to be anodic to steel, can be handled open to the air in tinned steel vessels. Some corrosion of the tin occurs at rates similar to those found for pure tin and in due course retinning may be necessary. The alloy layer in hot-dipped tin coatings is cathodic to both tin and steel and, under aerated conditions may stimulate the corrosion of both metals, but this effect appears to be unimportant in practice. 

As a general rule, foods which are not to be frozen are handled and stored at a temperature just above their freezing point, providing this does no damage (exceptions are fruits such as bananas and lemons). Produce which is to be frozen must be taken down below the freezing point of the constituents. Since foodstuffs contain salts and sugars, the freezing process will continue down to -18°C and lower. 

Frozen Foods. Corrosion caused by the reaction of foods with aluminum containers is unusual if the products are handled and stored at 0°F or lower. However, the inevitable bad handling of frozen foods during commercial distribution causes undesirable thawing. In this condition, not only does the food deteriorate, but it can also attack the container. Such unwanted reactions can be effectively controlled by using coated aluminum containers. Since aluminum is highly compatible with frozen fruits and citrus juices, it has been used extensively as a liner for fiberboard composite cans, as complete aluminum cans, or as ends in combination with steel can bodies in the frozen food industry. 

Most importantly the MR based systems acquire information from the internal parts of the fruit. This complements the primarily surface information currently obtained in the handling of fresh fruits and vegetables. 

With the advent of DDT as an important insecticidal material, much work has been required to study its persistence in the field and its tolerance by animals and plants. For the past 5 years this laboratory has been engaged in estimating residues on approximately 20,000 surface and penetration samples. These included a wide variety of materials, such as alfalfa, fruits, vegetables, nuts, leaves, twigs, soil, peat moss, wooden slats, galvanized iron, and tar paper. Techniques had to be developed to handle this large volume and variety of samples routinely and expeditiously. 

This factor is handled by applying the chemical not later than 30 days before harvest on crops that might hold some residual taste. On other crops it has been possible to use the chemical to within 2 weeks of harvest without retaining undesirable taste. This point is largely one of varieties, so that it becomes necessary to specify on labels which crops must be treated before fruits or heads form, which can be treated up to 2 or 3 weeks prior to harvest, and which have no particular time limit. The following fruits and vegetables are among those satisfactorily treated. 

Yahia EM. 2006. Handling tropical fruits. In Scientists Speak. Alexandria, VA World Foods Logistics Organization, pp. 5-9. 

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