Fruit Produce Facts English

Maturity Indices

Guava fruits are picked at the mature-green stage (color change from dark- to light-green) in some countries where consumers eat them at that stage. In countries where consumers prefer ripe guava, the fruits are picked at the firm-yellow to half-ripe (softer) stage for long-distance transport or at the fully-ripe (yellow and soft) stage for local markets.

Quality Indices

• Color is a good indicator of ripeness stage
• Size and shape may be important in some markets
• Freedom from defects, insects, and decay
• Firmness and extent of gritty texture due to the presence of stone cells (sclereids)
• Flesh color depends on cultivar and can be white, yellow, pink, or red
• Amount of seeds in the flesh (the fewer the better)
• Aroma intensity
• Soluble solids and acidity
• Guava is one of the richest sources of vitamin C (200 to 400 mg per 100g fresh weight) and some cultivars are also rich in vitamin A

Maturity & Quality Photos

Title: Quality (1)

Photo Credit: Adel Kader, UC Davis

Title: Quality (2)

Photo Credit: Adel Kader, UC Davis

Title: Quality (3)

Photo Credit: Adel Kader, UC Davis

Optimum Temperature

• 8-10°C (46-50°F) for mature-green and partially-ripe guavas (storage potential = 2-3 weeks)
• 5-8°C (41-46°F) for fully-ripe guavas (storage potential = 1 week)

Optimum Relative Humidity

90-95%

Rates of Respiration

Physiological and Physical Disorders

Chilling injury. Symptoms include failure of mature-green or partially-ripe guavas to ripen, browning of the flesh and, in severe cases, the skin, and increased decay incidence and severity upon transfer to higher temperatures. Fully-ripe guavas are less sensitive to chilling injury than mature-green guavas and may be kept for up to a week at 5°C (41°F) without exhibiting chilling injury symptoms.

External (skin) and Internal (flesh) browning. Guavas are sensitive to physical damage during harvesting and handling all the way to the consumer. Symptoms include skin abrasions and browning of bruised areas.

Sun scald. Guavas exposed to direct sun light may be scalded. In some countries, paper bags are used to cover guava fruits and protect them from solar radiation and insect infestation while on the tree.

Pathological Disorders

Most of the postharvest disease problems begin in the orchard as latent infection in developing fruits. Diseases include anthracnose (caused by Colletrotrichum gloeosporioides and associated species), aspergillus rot (caused by Aspergillus niger), mucor rot (caused by Mucor hiemalis), phomopsis rot (caused by Phomopsis destructum), and rhizopus rot (caused by Rhizopus stolonifer).

Disease control strategies include good orchard sanitation, effective preharvest management to reduce infection, careful handling to reduce physical damage, prompt cooling to 10°C (50°F) and subsequent maintenance of that temperature throughout the handling system.

Insect Control

Guavas are a preferred host for fruit flies and must be treated for disinfestation to be accepted in many countries. One of the insect control treatments is heat either as immersion in 46°C-water for 35 minutes or exposed to hot air at 48°C for 60 minutes. Another potential insect control treatment is irradiation at 0.15-0.30 kGy.

February 1999