Quince (Mespilus germanica)

Medlar (Mespilus germanica L.) is a deciduous fruit tree belonging to the Rosaceae (rose) family, with a small crown structure.

This species typically grows to a height of 3–5 metres and features white-pink, fragrant, and self-fertile flowers. It is pollinated by bees, with flowering occurring generally between May and June.

As a climacteric fruit, medlar fruits become edible after harvest when their high tannin content and astringent taste diminish, resulting in softening and browning of the flesh.

Origin and Distribution

The genus Mespilus is native to Southwest Asia and Southeast Europe, with approximately 189 species reported. The only species widely known for commercial and consumption purposes is Mespilus germanica. Historically, this species is believed to have been cultivated in northern Iran around 3,000 years ago, introduced to Rome around 200 BCE, and reached Greece approximately 700 years ago. Today, it is cultivated only in limited areas, with various local and registered varieties grown in Germany, the Netherlands, and Türkiye.

Fruit Characteristics and Yield

The number of flowers emerging from flower buds varies among genotypes, averaging between 32 and 75. Fruit set rates range from 36.2% to 68%. Fruits are typically round-oval in shape, five-seeded, and fleshy. Fruit weights vary, with yields ranging from 5 to 15 kg per tree. High yields have been observed in some genotypes grafted onto quince, particularly in individuals aged 5 to 10 years.

Nutritional Content and Functional Properties

Medlar fruit is rich in sugars, organic acids, pectin, carotenoids, and polyphenols. Its polyphenol oxidase activity has been found to be higher than in many other fruit types. This characteristic enhances the fruit’s antioxidant capacity and may offer potential health benefits.

Conservation and Breeding Studies

Eleven superior genotypes identified in this study (e.g., 60 NT 001, 60 NA 001) have been conserved in controlled plots for further observation and registration. These selection efforts, aimed at preserving local varieties and evaluating them commercially, contribute to the sustainability of genetic diversity.

Medlar in Tokat Ecology

A field survey conducted in Tokat identified a total of 2,605 natural medlar populations. High densities were particularly observed in the villages surrounding Niksar district. From these populations, 293 genotypes were selected through preliminary screening, and subsequently, 62 genotypes were chosen based on fruit size, tree yield, and other morphological and physiological criteria.

All of these genotypes have been diagnosed as belonging to the species Mespilus germanica L.

Image of Medlar Fruit and Medlar Tree. (Generated by YZ.)

Benefits of Medlar Fruit

1. High Antioxidant Capacity: Antioxidants combat free radicals in the body, helping to prevent cellular damage and potentially reducing the effects of chronic diseases and aging.
2. Supports Digestive Health: Its high pectin content (soluble fiber) makes it beneficial for the digestive system.
3. May Help Regulate Blood Sugar: Its fiber content contributes to a more balanced rise in blood glucose levels.
4. Strengthens the Immune System: Vitamins (particularly A and C) and minerals present in medlar support immune function.
5. Anti-inflammatory Effects: Certain compounds in medlar are believed to possess anti-inflammatory properties, which may help reduce inflammation in the body.
6. Supports Bone Health: Some studies indicate that fruits like medlar contain minerals that may help maintain bone density.

Illustration of the interior of a Medlar Fruit. (Generated by YZ.)

Use of Medlar (Mespilus germanica) Powder in Functional Food Production: A Biscuit Example

Medlar fruits were dried using microwave, convective, and vacuum drying methods, then ground into powder. This powder was used in biscuit production, substituting 0% (control), 10%, 20%, and 30% of wheat flour. The resulting biscuits were evaluated for physical, chemical, nutritional, and sensory properties.

Findings

• Color: Microwave-dried medlar powder exhibited the highest redness (a*) value, while convective drying produced the highest yellowness (b*) value. Vacuum drying yielded the highest lightness (L*) values.
• Physical Properties: As the substitution level of medlar powder increased, biscuit diameter and spread ratio increased, while thickness, hardness, and brittleness decreased.
• Chemical and Nutritional Analysis: Drying methods did not significantly affect protein, ash, or fat content. However, vacuum-dried powder showed the highest levels of total phenolic content and antioxidant activity.
• Sensory Evaluation: Panelists most preferred biscuits containing 10% medlar powder produced by vacuum drying, based on taste, appearance, and overall acceptance.

Illustration of Biscuit Production Steps Using Medlar Powder. (Generated by YZ.)