Fruits and Vegetables - Definitions and Classification

Fruits & Vegetables - Definitions

• Vegetables are the edible parts of herbaceous plants.
• Herbaceous plants have flexible stems with little to no woody part.
• Vegetables are often grouped by the edible part, like leaves, stems, or roots.

Fruits - Definitions & Classification

• Fruits are the mature ovaries of flowering plants.
• Ovaries contain seeds that develop after fertilization.
• Fruits' main purpose is to spread plant seeds.
• Fruit classifications include: Simple, Aggregate, Multiple, and Accessory.

Parts of a Plant

• Fruits: Avocado, cucumber, eggplant, okra, pepper, pumpkin, snap beans, squash, tomato
• Flowers: Artichoke, broccoli, cauliflower
• Stems & Shoots: Anise (fennel), asparagus, celery, kohlrabi
• Leaves: Beet greens, bok choy, Brussels sprouts, cabbage, chard, Chinese cabbage, collards, dandelion greens, endive, escarole, kale, lettuce, mustard greens, parsley, romaine spinach, turnip greens, watercress
• Tubers: Ginger root, potato, sunchoke
• Roots: Beet, carrot, celeriac, jicama, parsnip, radish, rutabaga, sweet potato, turnip
• Seeds: Beans, corn, lentils, peas

Pigments & Nutrients

• Carotenoids: Fat-soluble pigments (yellow, orange, red, purple) with antioxidant properties. Examples: carotene, lycopene, xanthophyll, lutein, zeaxanthin. Found in carrots, oranges, peaches, pineapples, red peppers, tomatoes, and winter squashes.
• Chlorophyll: Fat-soluble pigment, slightly soluble in alkaline media, responsible for green color in plants and algae. Essential in photosynthesis.
• Flavonoids: Water-soluble pigments with antioxidant properties. Some examples: anthocyanin, anthoxanthin, betalains. Found in berries, cauliflower, onions and beet roots.

Nutrients & Health Benefits

• Good sources of dietary fiber, potassium, folate, vitamin A, and vitamin C.
• Commonly low in fat and calories, and cholesterol free.
• Phytochemicals offer anti-inflammatory, anti-oxidant, and anti-cancer effects.

Vegetable & Fruit Storage

• Fruits: Store ripe fruits for a shorter period, unripe in a paper bag. Grapes are best stored unwashed in refrigerator in plastic bag.
• Vegetables: Store at room temperature or in the refrigerator depending on the type of vegetable. Keep vegetables in refrigerated crisper drawer to preserve moisture and to maintain freshness.

Browning of Fruits & Vegetables

• Tannins: Naturally occurring polyphenols; bitter taste and astringent feeling. Common in unripe fruits.
• Enzymatic browning: Reaction of tannins with PPO enzymes in presence of oxygen.
• To avoid browning: heat, acid, cold temperatures (inhibits, but doesn't prevent), and antioxidants (ascorbic acid & sulfur compounds).

Preparation Methods to Preserve Color

• Blanching: Foods cooked briefly in boiling water, then plunged in ice water. This helps retain color and stops the cooking process.

Ripening and Storage

• Climacteric Fruits: Continue ripening after harvest (e.g., apples, avocados, bananas, tomatoes).
• Non-climacteric Fruits: Best ripen before harvest (e.g., blueberries, cherries, grapes, strawberries).

Sensitivity to Cold

• Non-chilling-sensitive commodities: Do not need to be stored in cold temperatures (e.g., Apple, Apricot, Avocado, Banana...).
• Chilling-sensitive commodities: need specific temperatures (e.g., bananas, melons, sweet potatoes).

Definitions of Fruit Types

• Berries: Fleshy fruits without a pit, entire ovary wall in a single flower.
• Citrus Fruits: Typically sour, with a waxy outer layer. Rich in vitamin C.
• Fleshy Fruits: Thick, soft, and succulent fruits. Larger in size, sometimes seeds edible along with the flesh e.g. melons and papaya.
• Pomes: Fruits with a central core surrounded by edible flesh and a tough outer layer. Apples and pears.
• Stone Fruits (Drupes): Have pulp on the outside and an inedible large, hard stone in the middle, plums, cherries, peaches, and mangoes.

Acidity in Fruits

• Acidity is due to organic acid in the vacuole.
• Acidity decreases as fruits ripen.
• Volatile and non-volatile acids.
• Common organic acids: citric, malic, tartaric, oxalic.