............................................... THE FOOD AND THE HEALTH

Activities to do. Read the explanations on food and food types and perform the first Multiple Choice Test. Then read the explanations on handling, preservation and marketing of food and perform the second Multiple Choice Test and the Crossword.


1. The concept of food
. The food is the every product that we eat or drink that provides nutrients to our cells. Examples of foods are fruits, meat and milk. The food is consistued by nutrients and other substances, such as vegetable fiber, stabilizers, coloring substances, etc

2 . The quality of food. The quality of a food depends on its nutritional value, which is equivalent to the proportion of nutrients that it contains, its healthiness or hygienic quality, its external appearance and its price.

3 . The classification of food. It can be classified in many different ways. One of the classifications mostly used is as follows:

The groups of food
Examples
The content of the nutrients
Types of structural nutrients and micronutrients
Types of energetic nutrients
1 . Milk and dairy products Milk, yogurts and cheeses Proteins, calcium and vitamins A, B and D Lipids
2 . Meat, fish and eggs Lamb, beef, cod and eggs

Proteins, iron and vitamin B2 (vitamin A in liver and eggs)

Lipids
3 . Starches Potatoes, beans, rice, bread and pasta Vegetable proteins, vitamin B1 and iron in legumes Carbohydrates
4 . Fruits, vegetables and herbs Beet, lettuce, spinach, pear, grape Iron, calcium and cellulose. When unboiled there are also vitamins A and C. In dry fruits there are also lipids Carbohydrates
5 . Oils Olive oil, lard and butter

Vitamins A and D. In olive oil there is also a vitamin E.

Lipids
6 . Sugars Sugar and sweets None Carbohydrates
7 . Beverages Water, wine and juices In fruit juices there is a vitamin C Carbohydrates


4. The food and the health

The food pyramid

4.1 The food pyramid. It is the pyramid formed by the ordering of food types according to the amount of each of them need to achieve a good diet.

• In the first step there are foods rich in feculas (starch). Are the ones that we need to receive in the greatest proportion.

In the second step there are foods rich in fiber (cellulose), starch and vitamins.

In the third step there are protein-rich foods.

In the fourth step there are oils and sugars, which are the foods that have to take with a lesser extent.

Nutrient content of the main food

4.2 Complete and incomplete foods.

The complete foods are those which present all of the types of nutrients and with a similar proportion that our body needs. An example of the complete food is milk. This is logical since it is the only food for newborns.

For the same reason the eggs in the animal world and the seeds in the vegetable world are relatively complete food.

The opposite are the incomplete foods such as sugar, oil and butter, since practically they contain not more than a one type of nutrient.

 

 

Multiple Choice (Spanish activity. Activity in English is under construction)


5. The handling of food supplies
. The food handling, whether in the field, in transport, in the market or in the kitchen, has to be done in a hygienic manner, ie without increasing microbial contamination. To do this is recommended to:

  1. Wash hands before handling food for cooking or eating.
  2. Not cough or sneeze over the food nor handle food while having an infectious disease such as the flu.
  3. Wash and keep clean all kitchen utensils.
  4. Not leave fresh or cooked foods at room temperature for a long time.
  5. Prevent defrosting up to the very moment of its use. This means to avoid breaking the cold chain.
  6. Keep clean the transport vehicles and food stores.

6 . The food preservation. All the methods of food preservation are intended to prevent or or make difficult the lifes of microbes that could and would feed on them and destroy them. We can differentiate the following methods:

1. The traditional treatments. Are salted (used for example to preserve the herring, cod and prosciutto), smoked (eg smoked salmon), crystallized (eg candied fruit) and fermented (bread, yogurt, beer, wine and cheeses like "cabrales" and "roquefort"). The basis of this method consists in that a non-pathogenic microbes make difficult for lifes of others which are pathogens.

2. The cold storage. Is a conservation in refrigerators, by maintaining a temperature between 4 and 8 ºC, in which the microorganisms can hardly multiply. Also part of this type of storage is conservation in freezers, by maintaining a temperature below -18ºC, in which water freeze and kill most of the microorganisms. In order not to lose many of the substances that provide flavor the defrosting has to be fast and the food cannot be freezed again.

3. The heat conservation. It is the pasteurization by heating the food between 72 and 80ºC for only 15 or 20 seconds (which is what is done for example with fresh milk, beer and fruit juices) and sterilization or heating food in temperature higher than 100ºC. Within it can be distinguished clasic sterilization or heating up to 120ºC for 20 minutes (which is what is done for example with sardine cans and glass jars with peppers, artichokes, etc..) and the UHT sterilization or heating to 140ºC for 3 seconds (which is what is done with the type of milk enduring for several months without vitamin losses).

4. The conservation by removing the water. It is the dehydration or evaporation of water by use of a hot air, and freeze drying or freezing and subsequent sublimation (removal) of chilled water by vacuum. This gives the coffee powder, milk powder, powdered mashed potatoes, instant soups, etc..

5. The irradiation. It is the use of ionizing radiation on food. It is used to slow the ripening of the fruits and destroy the insects and microorganisms that may be present.

6. The food additives. These are the chemicals that are added to food to help preserve and maintain their appearance (color, smell and texture). The are added only when needed, effective and safe for health. Each additive in Europe is called an E (European) followed by a number. There are distinguished the colorants such as chlorophyll (E-140), preservatives such as sodium nitrite (E-250) and antioxidants such as citric acid (E-330).

7 . The distribution of food. To be properly informed the food should be labeled and it should not be false advertising.

The correct labels are those which indicate the product name, the state of the food, the preservation process, the list of ingredients in descending order and by additives or their respective codes, weight or volume content, the expiration date or best before date, the name of the responsible company and number of the manufacturing batch.

In the food publicity besides the nutritional quality displays there is also the information about the price and the preservation period that it presents.

8 . Genetically modified foods. Are the foods that were made from genetically modified organisms, ie organisms developed from cells to which one or more genes from other species has been inserted in order to improve its characteristics. So for example, variety of transgenic corn has been obtained which is more resistant to blights by possessing a gene from wheat; a variety of tomato that matures slowly, which allows the farmer to have more time to transport it; and a transgenic variety of salmon that resists better cold temperatures thanks to a gene of a fish species from Arctic Sea. All genetically modified food before obtaining the market approval must overcome a severe controls to ensure that they do no harm to the humans and that transgenic organisms from which they came do not constitute any danger to the maintenance of natural biodiversity.

Multiple Choce Test (Spanish activity. Activity in English is under construction)

Crossword (Spanish activity. Activity in English is under construction)
 

 

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