Acids and Food Sources
Acids
Acids are substances which are capable of turning blue litmus paper to red The Latin word “acid” has been derived word, Acidus which means “sour” Many fruits and vegetables are sour in taste because they contain acid. They are acid in nature, eg grape fruit, lime, lemon, etc.
Examples of acids are: Sulphuric acid Phosphoric acid, Lactic acid, Nitric acid, Formic acid, Tartaric acid, Hydrochloric acid and Citric acid
Acid and Base. Meaning and Physical Properties
Acid Examples
- Lactic acid: It is produced in the muscles during intense physical activity and causes muscle fatigue. It is also used in the food industry as a preservative and flavoring agent, and in the pharmaceutical industry for the production of drugs and cosmetics.
- Lactic acid: It is also produced during the fermentation of milk and is responsible for the sour taste of yogurt, kefir, and other dairy products. It is used in the food industry for the production of cheese, sourdough bread, and other fermented foods.
Acids and food source of acids ( Meat, fruits and vegetables)
Acids are a type of substance that tastes sour and can turn blue litmus paper to red. They are found in many things, including some foods we eat.
One example of a food that contains acids is meat. When we eat meat, it gets broken down in our stomach by a type of acid called hydrochloric acid. This acid helps our stomach break down the food so our body can use the nutrients to stay healthy and strong.
Another source of acids in our diet is fruits and vegetables. Some fruits like lemon, lime, and grapefruit contain citric acid, while others like oranges, tangerines, and pineapples contain ascorbic acid (also known as vitamin C). Vegetables like tomatoes and spinach contain malic acid, which gives them their tart taste.
These acids in fruits and vegetables not only give them their taste but also help our body absorb important vitamins and minerals that we need to stay healthy.
So, acids are not always bad for us. They play an important role in our body and are also found in some of the foods we eat. It’s good to eat a variety of foods that contain acids so we can get all the nutrients our body needs.
Evaluation
- Which of the following is an example of an acid found in fruits? a) Hydrochloric acid b) Sulphuric acid c) Citric acid d) Phosphoric acid
- What type of acid is responsible for the sour taste of yogurt? a) Lactic acid b) Nitric acid c) Formic acid d) Tartaric acid
- Which type of acid helps our stomach break down food? a) Ascorbic acid b) Malic acid c) Hydrochloric acid d) Citric acid
- What Latin word does “acid” come from? a) Bitter b) Sour c) Sweet d) Salty
- Which of the following is an example of a food that contains acid? a) Bread b) Pasta c) Meat d) Cheese
- What color does blue litmus paper turn in the presence of an acid? a) Red b) Blue c) Green d) Yellow
- What type of acid is found in batteries? a) Nitric acid b) Sulphuric acid c) Citric acid d) Lactic acid
- Which type of acid is found in lemons? a) Hydrochloric acid b) Citric acid c) Phosphoric acid d) Formic acid
- What role do acids in fruits and vegetables play in our body? a) They help break down food in our stomach b) They give fruits and vegetables their taste c) They help our body absorb important nutrients d) All of the above
- What is the purpose of eating a variety of foods that contain acids? a) To avoid acids altogether b) To get all the nutrients our body needs c) To prevent acid reflux d) None of the above
Lesson Presentation
Lesson Plan Presentation: Acids and Food Sources
Grade Level: 4th grade
Objectives:
- Students will be able to identify different types of acids found in food sources.
- Students will be able to describe the role of acids in our body.
- Students will be able to recognize the importance of eating a variety of foods that contain acids.
Materials:
- Blue litmus paper
- Samples of foods containing acids (e.g. lemon, grapefruit, yogurt, spinach, etc.)
- Poster board with pictures and descriptions of different types of acids
Introduction:
- Begin the lesson by asking students if they know what acids are and where they can be found.
- Show a sample of blue litmus paper and explain that it can be used to test for the presence of acids.
- Briefly discuss the Latin origin of the word “acid” and its meaning (“sour”).
Body:
- Introduce the different types of acids found in food sources, including citric acid, lactic acid, and malic acid.
- Provide examples of foods that contain these acids (e.g. citrus fruits, dairy products, and vegetables).
- Show pictures and descriptions of other types of acids found in non-food sources (e.g. sulphuric acid in batteries).
- Discuss the role of acids in our body, including helping to break down food in our stomach and aiding in the absorption of important nutrients.
- Emphasize the importance of eating a variety of foods that contain acids to ensure that we are getting all the nutrients our body needs.
Activity:
- Have students work in pairs to test samples of foods for the presence of acids using blue litmus paper.
- After testing, have them share their results with the class and discuss the types of acids found in the different foods.
- As a class, create a chart of different foods and their acid content.
Conclusion:
- Review the different types of acids found in food sources and their role in our body.
- Emphasize the importance of eating a balanced diet that includes a variety of foods containing acids.
- Encourage students to continue exploring the topic on their own and to be mindful of the foods they eat.
Assessment
- ___________ are substances that can turn blue litmus paper to red.
- The Latin word “acid” means ___________.
- Citric acid is found in fruits such as ___________ and ___________.
- Lactic acid is responsible for the sour taste of ___________.
- The acid found in our stomach that helps break down food is called ___________ acid.
- ___________ acid is found in batteries.
- Malic acid gives vegetables such as ___________ and ___________ their tart taste.
- Blue litmus paper turns ___________ in the presence of an acid.
- Eating a variety of foods that contain acids helps our body absorb important ___________.
- ___________ is an example of an acid that is found in many different types of fertilizers.
