WEEKLY HOME STUDY PACKAGE - WEEK 3 (19/07/21 – 23/07/21)

Subject HOME - ECONOMICS Year/Level 13 Strand 13.2– Food & Nutrition Sub-strand HEC 13.2.4 Food Supply – Food Commodities Content Learning List the food commodities into various groups. Outcome

LESSON NOTES: FOOD COMMODITY - FRUITS

Classification of Fruits  Simple: single ovary into one flower e.g. oranges, pear, apple, mangoes, guava.  Aggregate: several ovaries into one flower e.g. Strawberries, grapes, blueberries, raspberries.  Multiple: cluster of several flowers that produce a single fruit. E.g. Pineapples, mulberries, fig, breadfruit. Types of fruits  Pomes: fruits have a core g. Apples and pears  Drupes: contain a single seed within a stone surrounded by a fleshy pericarp, which is the edible fruit. It is also known as stone fruits eg apricots, peaches, plums and cherries, Fiji e.g. Dawa, mango.  Berry fruits: They have a soft and fleshy pericarp which contains seeds e.g. Strawberries, blackberries  Citrus fruits: Flesh segments with a high acidic taste.eg. Oranges, mandarin’s pineapples,

Chemical Composition in relation to pigments:

1. Colour: – Gives fruits/ vegetables Red – Blue colour. E.g. Blueberries Anthoxanthin –creamy/ white or colourless. E.g. Bananas, radish. – only pigment with nitrogen atom. It gives purple – red, yellow colour. e.g. beetroot – yellow – orange colour e.g. pawpaw, mangoes. Lycopene is one of the carotenoid pigment found in tomatoes, watermelon and grapefruit. – green colour. e.g. guava

The predominant pigments are , anthocyanin’s  The mixing of various colours affect fruit use in juice making  Tins and cans have effects on fruit  Deteoriation of canned fruits on storage due to light, and warm temperatures

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2. Nutritive value: Carbohydrates: the chief energy nutrient present as sugars. Traces of fats are present with the exception of coconuts having 35% and avocados with 17% fats and olives. There are small amounts of protein, water is 85% and they are valuable sources of vitamins and minerals. The calorie value is higher than vegetables due to the sugar content .Citrus fruits are the best sources of vitamin C.

3. Flavour: Each fruit has its characteristic flavour and the flavour is tart, fragrant, and sweet. Flavour in fruits is influenced by the following factors:  Aromatic compounds- They determine characteristic flavours of fruits . - Esters - pineapples odour and flavour. - Aldehydes (benzyl dehyde derivatives) and various alcohols are responsible for the floral and fruity part of the aroma of fruits such as apricots.  Acids: Organic acids in fruits also contribute to flavour: Malic and caustic acids are two acids found common in fruits, and tartaric acid contributing to grape flavour.  Essential Oils: The leathery skin of oranges and limes contains oil and this may be expressed and used as flavoring as the basis of extracts by combining the oils.  Other components: Mineral salts, sugars and phenolic compounds contribute to flavour. - Fruits cooked in metallic containers form acid salts with the metals. - Canned fruits contain tin or iron salts, which are not harmful but may sometimes produce metallic flavour impact. Thus, lacquering process is done where cans are coated before fruits are packed to prevent the fruit pigment Anthocyanin reacting with the tin/ metal which can produce bluish red or violet colour. - A bitter taste and an astringent or puckery feeling in the mouth are produced by phenolic compounds, which appear to be present in the largest amount in immature fruits.

ACTIVITY/ QUESTIONS

1. Fleshy fruits have three classifications. Identify the two classifications of fruits given below.

(2 marks)

2. Account for each of the following statements: (2 marks) (i) Fruits that are to be eaten raw or cooked with their skins should be thoroughly washed before use.

(ii) Pigment contents should be considered when mixing various fruits to make fruit juice. (2 marks)

3. Name the pigments that are responsible for the colour of the following fruits. (i) Tomatoes (ii) Pineapples (2marks) 4. Differentiate between Pomes and Drupes? (2 marks)

5. Name two compounds responsible for the flavour of fruits? (2 marks) 6. Discuss the reason for the use of lacquered tin for canning red fruits and vegetables by food Industries. (3 marks)

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