FRUITS AND VEGGIE

• Vegetables


  Parts of plants such as roots, tubers, bulbs, stems, shoots, leaves, fruits and flowers used raw or cooked, served with the meal as viands or salads but not as desserts
• Fruits


  Fleshy, juicy products of plants that are seed-containing, usually eaten as an appetizer or dessert when ripe, edible even without cooking
• Classification of Vegetables by Plant Part Used

  • Roots
  • Tubers
  • Bulbs
  • Seeds
  • Stems and Shoots
  • Leaves
  • Fruits
  • Flowers
• Classification of Vegetables by Chemical Composition

  • Carbohydrate-rich
  • Protein-rich
  • Fat-rich
  • High-moisture
• Classification of Fruits

  • Aggregate Fruits
  • Berry
  • Drupe
  • False Berry
  • Hesperidium
  • Multiple Fruit
• Proximate Analysis


  Determination of the nutritional value of food by estimation of protein, fat, carbohydrate, moisture content, etc.
• Fruits and Vegetables


  • Generally higher moisture content than most other foods
  • Contains water, structural carbohydrates, cellulose, and protopectin
  • Contains available carbohydrate (starch and sugar)
  • Contains protein, traces of fats, and vitamins and minerals
• Nutritive Value of Fruits


  • High in water content
  • Fair to excellent source of calories (due to sugar content)
  • Good source of fiber
  • Contains essential macrominerals, microminerals, vitamins, and vitamin-like factors
• Nutritive Value of Vegetables

  • High in water content
  • Lower in calories and proteins than grains and legumes
  • Fair to excellent source of fiber
  • Rich source of essential minerals and vitamins
  • Vary widely in composition and nutritive value depending on the part of the plant used
• Sources of Vitamin A

  • Green leafy vegetables
  • Yellow fruits
• Sources of Vitamin C

  • Guavas
  • Tomatoes
  • Citrus fruits
  • Other juicy fruits
• Sources of Vitamin B-Complex

  • Beans
  • Leafy greens
• Flavor Components of Fruits and Vegetables


  • Sugars
  • Acids
  • Sulfur Compounds
  • Tannins or Phenolic Compounds
• Chlorophyll


  • Responsible for the green pigments of vegetables and fruits
  • Two green forms: Chlorophyll A and B
  • Two yellow forms: Carotene and Xanthophyll
  • Not soluble in water, but pure chlorophyll is soluble in fat
  • Intensified in the presence of small or dilute alkali
  • Turns yellow green then brownish green due to the action of acid
  • Decomposed by heat, depends on temperature and length of cooking
• Carotenoids


  • Insoluble in water but soluble in fats
  • Types: Carotenes and Xanthophylls
  • Lycopene is the red pigment in tomatoes
  • Capxanthin is the red pigment in pepper
  • Not affected by acids and alkalis
• Chlorophyll


  Green pigment in plants
• Reaction to Acids


  Chlorophyll turns yellow green then brownish green due to the action of the acid changing chlorophyll to substance called PHEOPHYTIN
• Effect of Heat


  1. Heat decomposes chlorophyll

  2. Depends on the temperature and length of cooking

  3. Dull-yellow and green colors
• Vegetables contain volatile and non-volatile acids
• Most of the volatile acids carried off with the steam if the vegetables are cooked uncovered
• It is better to leave the pan uncovered for the first few minutes then covered in the latter part of cooking
• Canned green vegetables such as peas, asparagus, and green beans develop a deep yellow green color due to the retention of the acids of plants in the sealed cans as well as the high temperature used for the canning process
• Carotenoids


  Pigments that are insoluble in water but soluble in fats
• Types of Carotenoids

  • Carotenes
  • Xanthophylls
• Lycopene


  Red pigment in tomatoes
• Capxanthin


  Red pigment in pepper
• Carotenoids are not affected by both acids and alkali
• Carrots and potatoes darkening of the color is not due to the pigments but rather due to caramelization of sugar
• Flavonoids


  Phenolic compounds
• Anthocyanin


  Pigments that give the red, purple, and blue color to many fruits, vegetables, flowers, and leaves like red-cabbage and beets
• Effect of Acid and Alkali on Anthocyanin

  They become redder upon addition of acids and bluer upon addition of alkalis
• Effect of Metals on Anthocyanin

  Makes anthocyanins to become violet
• Anthoxanthins


  Almost colorless or pale yellow pigments which are found in light colored vegetables like potatoes and yellow skinned onions
• Anthoxanthin solubility


  Water soluble
• Effect of pH on Anthoxanthins

  Turns yellow or orange in the presence of alkali
• Effect of metal on Anthoxanthins

  Iron salt causes brownish discoloration
• Enzymatic Browning


  Enzymatic darkening of plant tissue in air due to the presence of dihydroxy-phenol derivatives such as cathecol, protocathecuic acid, and caffeic acid
• Tannins are abundant in nature and are probably formed by the breakdown of flavonoids
• For enzymatic browning to occur, fruits and vegetables must have the phenolic substance which on exposure to air, is oxidized, the process being promoted by the enzyme
• Ways to Prevent Enzymatic Browning

  • Changing from the optimum conditions for activity of the enzymes
  • Slowing the browning by dipping fruits for salads in kalamansi juice
  • Use of reducing substances or inhibitors like ascorbic acid
  • Removal of Oxygen by vacuum packing of food products or by replacement of air with carbon dioxide or nitrogen
  • Preventing Oxygen from coming in contact with the food
  • Sugar and sugar solutions prevent the oxygen from coming in contact with the fruit
  • Destroying the Enzyme by cooking the food and scalding of vegetables before freezing