Cooking Asparagus The Fun And Easy Way

Preparation is the key when you're going to cook asparagus. There are several methods of cooking boiling, grilling, steaming, or roasting. The microwave is also a good option when cooking asparagus. Cut the asparagus into sections and you can use it in stirfries you can also blanch the asparagus and use it in vegetable dips. Of course, there's nothing like steamed asparagus with butter, salt, and pepper.

When buying asparagus make sure that it is fresh, the asparagus will taste much better and can be kept for two to three days when properly stored. Once you get the asparagus home and ready to prepare, you'll need to trim it. The easiest way to trim asparagus before cooking is to simply do it by hand by bending the stock until it breaks. If it will not break but only bends, it is probably old and will not be as fresh as you would like it. Some cooks prefer to peel the bottom of the stocks this is not really necessary but sometimes helps when the stocks are a little woody. Contrary to popular belief the thicker asparagus is actually more flavorful than the pencil thin variety that most people want to buy.

An easy way to peel asparagus if you decide to go that route, is to lay a stalk on the counter or a cutting board and use a vegetable peeler. Starting at the top of the asparagus peel all the way to the end. The main reason anybody would peel asparagus, as I mentioned above, would be to make the asparagus more tender. You don't need to completely peel the asparagus either, simply peel down one one side to allow moisture to enter the asparagus while it is cooking.

If you want to steam the asparagus here is a simple method. After you have timmed your asparagus to the size you need, and optionally peeled it, place them in a saucepan and about an inch of water. Another steaming method you can use when cooking asparagus is to stand them vertically. Make sure you tie the bundles at the bottom and the top so they don't fall over in the pan. They should steam for approximately 5 to 10 minutes depending on the thickness.

Boiling is a great way to cook asparagus also. You want to use just enough water to cover the asparagus but make sure all the stems face the same direction and are covered with water. The asparagus will take between four to six minutes to cook completely, but again that depends on the size.

One method I really enjoy is using the grill. Cooking asparagus on the grill either directly over the fire or on skewers gives a great smoky flavor. Depending how you like them, cook the asparagus for anywhere from 30 seconds to 10 minutes. Another great way to cook the asparagus is to wrap them in foil with a little bit of olive oil and salt and pepper and cook them on the grill for 10-20 minutes. You'll have a great treat.

On those winter days when you really don't want to cook asparagus on the BBQ, another great option is roasting. Simply heat the oven to 425° F, and lay the asparagus flat on a baking sheet lined with foil. You can put any seasoning you want on the asparagus when roasting; salt, pepper, lemon pepper or any other spice that you have on hand are good. You will be rewarded with a nice tender stalk with a roasted flavor in about two to three minutes.

How Does A Refrigerator Work?

This is similar to what happens inside older refrigerators. Instead of water, though, the refrigerator uses chemicals to do the cooling.

There are two things that need to be known for refrigeration.
1. A gas cools on expansion.

2. When you have two things that are different temperatures that touch or are near each other, the hotter surface cools and the colder surface warms up. This is a law of physics called the Second Law of Thermodynamics.

Old Refrigerators

If you look at the back or bottom of an older refrigerator, you'll see a long thin tube that loops back and forth. This tube is connected to a pump, which is powered by an electric motor.

Inside the tube is Freon, a type of gas. Freon is the brand name of the gas. This gas, chemically is called Chloro-Flouro-Carbon or CFC. This gas was found to hurt the environment if it leaks from refrigerators. So now, other chemicals are used in a slightly different process (see next section below).

CFC starts out as a liquid. The pump pushes the CFC through a lot of coils in the freezer area. There the chemical turns to a vapor. When it does, it soaks up some of the heat that may be in the freezer compartment. As it does this, the coils get colder and the freezer begins to get colder.

In the regular part of your refrigerator, there are fewer coils and a larger space. So, less heat is soaked up by the coils and the CFC vapor.

The pump then sucks the CFC as a vapor and forces it through thinner pipes which are on the outside of the refrigerator. By compressing it, the CFC turns back into a liquid and heat is given off and is absorbed by the air around it. That's why it might be a little warmer behind or under your refrigerator.

Once the CFC passes through the outside coils, the liquid is ready to go back through the freezer and refrigerator over and over.

Today's Refrigerators

Modern refrigerators don't use CFC. Instead they use ammonia gas. Ammonia gas turns into a liquid when it is cooled to -27 degrees Fahrenheit (-6.5 degrees Celsius).
A motor and compressor squeezes the ammonia gas. When it is compressed, a gas heats up as it is pressurized. When you pass the compressed gas through the coils on the back or bottom of a modern refrigerator, the hot ammonia gas can lose its heat to the air in the room.

Remember the law of thermodynamics.

As it cools, the ammonia gas can change into ammonia liquid because it is under a high pressure.

The ammonia liquid flows through what's called an expansion valve, a tiny small hole that the liquid has to squeeze through. Between the valve and the compressor, there is a low-pressure area because the compressor is pulling the ammonia gas out of that side.
When the liquid ammonia hits a low pressure area it boils and changes into a gas. This is called vaporizing.

The coils then go through the freezer and regular part of the refrigerator where the colder ammonia in the coil pulls the heat out of the compartments. This makes the inside of the freezer and entire refrigerator cold.
The compressor sucks up the cold ammonia gas, and the gas goes back through the same process over and over.

How Does the Temperature Stay the Same Inside?

A device called a thermocouple (it's basically a thermometer) can sense when the temperature in the refrigerator is as cold as you want it to be. When it reaches that temperature, the device shuts off the electricity to the compressor.

But the refrigerator is not completely sealed. There are places, like around the doors and where the pipes go through, that can leak a little bit.

So when the cold from inside the refrigerator starts to leak out and the heat leaks in, the thermocouple turns the compressor back on to cool the refrigerator off again.
That's why you'll hear your refrigerator compressor motor coming on, running for a little while and then turning itself off.

Today's refrigerators, however, are very energy efficient. Ones sold today use about one-tenth the amount of electricity of ones that were built 20 years ago. So, if you have an old, old refrigerator, it's better to buy a new one because you'll save money (and energy) over a long period of time.

For more information go to:

• Argone National Laboratory - Ask A Scientist (http://newton.dep.anl.gov/newton/askasci/1993/eng/ENG30.HTM)

• Mr. Hand's 8th Grade Science Site (www.mansfieldct.org/schools/mms/staff/hand/heatrefrig.htm)

• How Stuff Works - Refrigerator (www.howstuffworks.com/refrigerator.htm)
• Science Treasure Trove - refrigerator page (www.education.eth.net/acads/treasure_trove/refrigerator.htm)

Packing House Operations for Fruits and Vegetables

Packing houses serve as a collection centre for fruits and vegetables prior to distribution and marketing. The houses can be simple packing sheds with a limited equipment and minimal operations or a large complex that is well equipped and with facilities for specialized operations. The types of operation carried out vary with different commodities and market requirements. Produce that are destined for export or supermarket outlets are often subjected to elaborate operations compared to local markets. Some of the operations are as follows:

Sorting and Trimming

Freshly harvested fruits and vegetables are sorted for uniformity in size, shape and varietal characteristics. Damaged, discoloured and decayed parts are removed to make the produce more attractive and prevent infection from the diseased parts.

Washing

Washing is necessary to remove extraneous materials from the field such as dirts, chemicals and latex. This is usually done before storage or immediate retailing of the produce. In order to r educe the incident of decay, chlorine is often added to the wash water.

Drying

Drying is done to remove excessive moisture from the surface of the produce. Excessive drying should be avoided to prevent wilting, shrinking and water loss.

Waxing

Waxing is done on certain types of fruits and vegetables such as ginger, tomato, citrus and melons to reduce water loss, thereby reducing shriveling. In addition to that, the application of edible wax will enhance the appearance of the produce.

Curing

Injured and bruised surfaces of root, rhizome and tuberous crops are allowed to heal by holding them at ambient temperatures for a few days. Curing initiates the formation of periderm layers at wound areas, thereby reducing moisture loss and microbial infection. Sufficiently cured vegetables can be stored for a longer period.

Chemical Treatments

Fungicides and growth regulators are commonly used to reduce decay and undesirable growth respectively. The use of chemicals should be closely supervised and within the recommended levels for human consumption.

Grading

Fresh fruits and vegetables are classified into groups according to a set of recognized criteria of quality and size, with each bearing an accepted name and size grouping.

Packaging

Produce are packed in suitable containers to provide protection against mechanical and biological damages during transportation and subsequent handling operations. Packaging materials should be of accepted standards with regard to strength, ruggedness and resistance to pressure. Packages should have adequate ventilation so that produce will not warm up as a result of heat arising from respiration. Excessive ventilation, however, may result in wilting.

Pre-cooling

Pre-cooling is an essential step prior to storage at low temperatures. It is the rapid removal of field heat from the produce to reduce the rate of respiration, microbial activity and refrigeration load. Pre-cooling can be done with chilled water, ice or cool air (forced air cooling), whereby the produce is cooled to the half cooling temperature.

Storage

Storage at low temperatures has been an effective mean of extending the shelf-life of fresh fruits and vegetables. It also enables orderly marketing and distribution of produce in time of peak production. Temperature requirements for different produce may vary depending on variety, location, stage of maturity and other factors. It is important to note that cool storage is a tool used to maintain quality but not to improve it.

Transportation

Proper handling of the produce during transportation is essential to reduce losses to a minimum and to maintain their quality from the farm to the packing house and from packing house to market. The used of refrigerated trucks to transport highly perishable and high value produce will maintain their quality over an extended duration. In non ventilated vans, temperature of the fruits or vegetables rises quickly, increasing respiration and decay.