Grapefruit

Grapefruit
Citrus paradisi Macf.
Citrus Genus — Citrus L.
Rutaceae Family

Description of Grapefruit

Grapefruit evergreen heat-loving shrub tree height 33–49 ft (10–15 m). Crown dense round pyramidal thin flexible branches. Bark trunk gray-brown rough young shoots smooth greenish. Leaves large leathery oval oblong-oval length 3.9–5.9 in (10–15 cm) width 2–3.1 in (5–8 cm) blunt slightly pointed winged petioles glossy dark-green above lighter below oil glands essential oil. Flowers large white diameter 1.6–2 in (4–5 cm) fragrant solitary clusters 3–20 leaf axils; calyx five-lobed petals 4–5 stamens 20–25 pistil multi-carpellate ovary short style. Fruits hesperidia flattened-spherical diameter 5.9 in (15 cm) weight 5.3–21.2 oz (150–600 g) thick peel (0.4–0.8 in/1–2 cm) light-yellow orange pink-red (red varieties); surface pitted oil glands; outer colored dense flavedo underlies white loose albedo; odor distinctive. Pulp juicy greenish-yellow light-yellow pink sour-sweet bitter (naringin) 10–14 radial segments soft dense walls mature separate. Seeds large light 0.4 in (1 cm) 10–20/fruit some seedless. Varieties flesh color (‘Rio Red’ red ‘Marsh’ white ‘Star Ruby’ pink) taste (sour sweet). Blooms March–May fruits October–February.

 

Distribution and Ecology of Grapefruit

Hybrid pomelo (Citrus maxima) orange (Citrus sinensis) Barbados XVII century India Malaysia Fiji. Wild unknown. Cultivated tropics subtropics USA (Florida California Texas) Mexico Brazil South Africa Israel India China Australia Mediterranean (Spain Morocco) Russia (Black Sea Caucasus Krasnodar Dagestan) Ukraine Moldova Uzbekistan Tajikistan Turkmenistan. Exporters USA South Africa. Loose drained sandy loamy pH 6.0–7.5. Heat 68–86°F (20–30°C); frost -28°F (-2°C) fatal young adults -19°F (-7°C) cover. Water (1–2/week) flowering fruiting no stagnation. Sun 8–10 hours. Grafting rootstocks (pomelo orange) cuttings; seeds rare 5–7 years fruit. Varieties ‘Duncan’ (white seeded) ‘Ruby Red’ (red) ‘Flame’ (sweet). Prune crown NPK pests (whitefly aphids scale). Phytoremediation accumulates elements attracts bees self-pollination. Invasive Australia uncontrolled seeds.

 

Raw Materials from Grapefruit

Main ripe fruits (pulp juice) peel (flavedo albedo) seeds rarely leaves flowers. Fruits October–February maturity (bright peel juicy pulp). Juice cold press 50–60% pulp. Peel manual mechanical dry 104–122°F (40–50°C) ventilated 15–20%. Seeds ripe dry 86–95°F (30–35°C) 5–10%. Leaves flowers May–June 95–104°F (35–40°C) 20–25%. Quality juice clear no sediment acidity 1.5–3%; peel humidity <12% oil ≥0.5%; seeds no mold. Store fruits 46–54°F (8–12°C) 2 months juice glass fridge 5 days (conserve) peel seeds paper leaves flowers cloth dry <12%. Shelf fruits 2 months juice 6 months (canned) peel seeds 2 years leaves flowers 1. Check mold insects (mealybug).

 

Chemical Composition of Grapefruit

Pulp juice (98% 90% water) glycoside naringin (0.1–<0.5% bitter) essential oil (0.1–0.2% limonene pinene) organic acids (citric 1.5–<3% malic oxalic) ascorbic (40–<60 mg% more mandarins 1.5 less oranges lemons) vitamins (A 0.02 mg% beta-carotene B1 0.037–0.053 mg% B2 0.031–0.045 mg% B6 0.045 mg% PP 0.23–0.30 mg% D) sugars (6–7%: sucrose 3–3.1% fructose 1.3–1.5% glucose 1.6–1.8% sweeter oranges) proteins (0.7–0.9%) fats (0.2–0.5%) carbs (9.8–10.6%) pectins (0.3–<0.5%) fiber (0.3–0.5%) minerals (potassium 181 mg% calcium 12–20 mg% magnesium 6 mg% phosphorus 15–17 mg% sodium 2 mg% iron 0.25–0.3 mg%) flavonoids (quercetin hesperidin) antioxidants (lycopene red). Peel ascorbic (265 mg%) oil (1–<2% limonene 90%) flavonoids pectins (<10%). Seeds fat oil (15–<20% linoleic) naringin. Leaves flowers oil (0.5–1%) flavonoids. Calories 30–40 kcal/100 g.

 

Uses and Benefits of Grapefruit

Naringin flavonoids anti-sclerotic antioxidant anti-inflammatory strengthen vessels cardiovascular. Ascorbic B vitamins immunity metabolism. Acids pectins digestion flora appetite. Juice pulp tonic diuresis pressure liver fatigue. Hypertension atherosclerosis avitaminosis post-infection surgery intoxication obesity diabetes (low GI) hypokinesia fatigue GI (hypoacid gastritis constipation). Peel oil aromatherapy stress mood. Seeds extracts antimicrobial.

 

Precautions for Using Grapefruit

Moderate (10–17 oz/300–500 ml juice 1–2 fruits/day) gastric irritation high acidity. Juice interacts drugs (statins antihistamines antidepressants antibiotics) CYP3A4 liver consult doctor. Peel oil photosensitization external avoid sun. Citrus allergy skin (redness itch). Seeds excess (0.18–0.35 oz/5–10 g) GI discomfort naringin.

 

Contraindications for Using Grapefruit

Peptic ulcers acute high-acid gastritis GERD pancreatitis cholecystitis hepatitis citrus allergy. Juice pulp CYP3A4 drugs (statins immunosuppressants antiarrhythmics) doctor. Children under 3 allergy GI risk. External oil eczema psoriasis wounds.

 

Medicinal Recipes with Grapefruit

1. Juice immunity tonic. Juice 1 grapefruit (5–10 oz/150–300 ml) dilute (1:1) sweeten honey sugar (no diabetics) drink 2–3 times day 20 min before meals >2 weeks avitaminosis post-infection.
   
2. Tonic fatigue. Mix 3.4 oz (100 ml) juice 1 tsp honey 1.7 oz (50 ml) water. Drink morning week.
   
3. Peel infusion digestion. 1 tbsp chopped dry peel 6.8 oz (200 ml) boiling steep 30 min strain. 1.7 oz (50 ml) 2 times day before meals constipation.
   
4. Seed oil massage. 5 ml seed oil 10 ml almond. Massage muscle fatigue 1–2 week.
   
5. Aromatherapy relax. 3–5 drops peel oil lamp 1.7 oz (50 ml) water 15–20 min stress.
   

 

Cosmetic Uses of Grapefruit

Antioxidant (flavonoids C) antiseptic (oil) tonic (naringin). Juice peel oily skin oil aroma massage seeds antimicrobial.

1. Oily skin mask. 2 tbsp juice 1 tbsp white clay 1 tsp honey. Face 10 min rinse warm. Weekly.
   
2. Pore toner. 3.4 oz (100 ml) juice 1.7 oz (50 ml) water 1 tsp apple vinegar. Wipe cotton 1–2 day.
   
3. Body scrub. 2 tbsp chopped dry peel 1 tbsp sugar 2 tbsp coconut. Massage 2–3 min rinse warm. Weekly.
   
4. Hair mask. 1 tbsp juice 1 yolk 1 tbsp seed oil. Roots 20 min shampoo. 1–2 week.
   

 

Culinary Uses of Grapefruit

Dietary vitamins minerals appetite digestion. Pulp juice fresh drinks desserts sauces jams liqueurs. Low-bitter (‘Marsh’ ‘Flame’). Peel candied oil seeds extracts. Tropics soldiers rations marches.

1. Fresh grapefruit. Halve remove seeds films sprinkle sugar honey 10 min (fridge 30 min). Spoon pulp juice.
   
2. Smoothie. Blend 1 grapefruit pulp 1 banana 3.4 oz (100 ml) yogurt 1 tsp honey. Breakfast.
   
3. Salad. 1 grapefruit pulp 1.76 oz (50 g) arugula 1 oz (30 g) feta 0.35 oz (10 g) pine nuts dress 1 tbsp olive 1 tsp lemon. Appetizer.
   
4. Sauce. Reduce 3.4 oz (100 ml) juice 1 tbsp sugar 1 tsp starch thick. Fish poultry.
   
5. Peel candied. Peel strips soak water 2 days (change) boil syrup (7 oz/200 g sugar 3.4 oz/100 ml water) 20 min dry 122°F (50°C) 4–5 hours.
   

 

Other Properties of Grapefruit

Peel oil perfumery food. Peel aroma rooms repel insects. Ornamental gardens greenhouses.