What apples are high in phloretin?

Phloretin is rapidly becoming a star ingredient in the fields of cosmetics, functional foods, and pharmaceuticals due to its powerful antioxidant, anti-inflammatory, and anti-aging potential. However, for raw material purchasers and product developers, a crucial question is: how should we choose raw materials, and which apples have higher Phloretin content?

Before discussing content, we must first clarify two often mentioned but easily confused concepts: Phloretin and Phloridzin.

Phloridzin: This is the glycosidic form of Phloretin, in which a glucose group is attached to the Phloretin molecule. Phloridzin is mainly found naturally in the roots, stems, leaves, and especially the fruits of apples. It has relatively good water solubility and is the main storage and transportation form of this type of compound in apples.

Phloretin: This is the aglycone form of Phloridzin after removing glycosides. Numerous pharmacological studies have shown that Phloretin is the core structure that exerts its primary biological activity. For example, according to multiple research reviews published between 2021 and 2023, Phloretin has shown significant effects in anti-tumor, regulating inflammatory responses, combating oxidative stress, and delaying aging.[1,3,4]

In the plant extract industry, the usual production process is to first extract Phloridzin, which is more abundant in content, from apples, and then hydrolyze and remove sugar groups through biotechnological means such as enzymatic hydrolysis or acid hydrolysis to obtain high-purity Phloridzin. Therefore, discussing which type of apple has high Phloretin potential is essentially equivalent to exploring which type of apple has abundant Phloridzin content.

Its content is complex, influenced by multiple factors such as variety, growth site, harvest maturity, planting environment, and even storage conditions. Although the latest (2022-2024) official testing reports and authoritative journal data for mainstream varieties in the Chinese market, such as Red Fuji and Guoguang, are not yet complete, based on existing research, we can draw the following key conclusions:
2.1 Core distribution area: Peel far exceeds pulp

This is widely recognized as the most important law in both industry and academia. Phloretin and its glycosides, as plant polyphenols, are mainly synthesized in the epidermal tissues of plants to resist UV radiation and external pathogen invasion. For example, a study clearly indicated that the content of Phloretin in apple peel can reach 80-420 mg/kg, while the content in fruit flesh is only 16-20 mg/kg, with a significant difference between the two.[6] Another analysis also provided a similar concentration range, with Phloretin content in apple peel and flesh ranging from 0.06 to 6.00 mg/100 g fresh weight (FW), with the majority concentrated in the peel.[5] 

2.2 Significant differences between varieties
In an analysis of four organic apple varieties, researchers measured the Phloretin content (in mg/100 g) in their skin and flesh. The results showed that the skin of Granny Smith (green apple) and Red Delicious (red snake fruit/red marshal) exhibited particularly outstanding performance.[7] This means that varieties with dark colors and a slightly sour taste may typically have higher levels of polyphenolic substances.
2.3 The impact of maturity: the potential of unripe fruits

The accumulation of secondary metabolites in plants is closely related to their growth cycle. Usually, immature fruits synthesize more phenolic compounds to resist external stress. Therefore, young or immature apples may have higher Phloretin content than fully ripe fruits.

For colleagues in the plant extract industry, although there is no absolute answer to "which type of apple is the best", following the idea of "skin is better than flesh, specific varieties are better, and industry standards escort", undoubtedly, we can more accurately discover this "golden" component (Phloretin ) in apples in this blue ocean full of opportunities.

For more details about Phloretin and Phlorizin, connect with Serrisha from APPCHEM. (Email: cwj@appchem.cn; +86-138-0919-0407)

Reference
[1]A deep dive into the orchard of health: Exploring the anti-cancer and anti-aging potential of apple polyphenols. Li-Ching Chen et al. [2025]
[2]Valorization of Apple Pomace: Production of Phloretin using a Bacterial Cellulose-Immobilized β-Glycosidase. J. M. Costa et al. [2022-10-28]
[3]Sustainable Exploitation of Apple By-Products: A Retrospective Analysis of Pilot-Scale Extraction Tests Using Hydrodynamic Cavitation. Not specified in the provided text. [2025-05-28]
[4]S. Behzad, A. Sureda et al. "Health effects of phloretin: from chemistry to medicine." Phytochemistry Reviews (2017). [2017-03-07]
[5]Trends in biochemical, anatomical mechanisms, and molecular aspects in enzymatic browning of apples: a review. Mostafa Z. Sultan et al. [2025-02-20]
[6]Pharmacological Aspects and Potential Use of Phloretin: A Systematic Review. Arokia Vijaya Anand Mariadoss et al. [2019]
[7]C. Remsberg. "Pharmacokinetics, Pharmacodynamics, and Formulation Development of Hydrophobic Xenobiotics." (2011). [2011-08-19]