Apple polyphenols are naturally occurring compounds found in apples, and their concentration varies depending on the fruit's maturity. Unripe apples contain approximately ten times more polyphenols than ripe ones, making them an ideal source for extraction. The isolation and purification process involves several steps:
First, unripe apple fruits are crushed using acidified methanol to break down the cellular structure. This is followed by extraction, filtration, and concentration through adsorption. The solution is then evaporated to remove methanol, leaving behind a concentrated extract. Further purification is achieved by precipitation with chloroform, and finally, the crude apple polyphenol (CAP) is obtained through freeze-drying.
The crude extract contains various bioactive compounds such as chlorogenic acid, catechin, epicatechin, apple condensed tannin, phloridzin, and anthocyanins. Among these, apple condensed tannin constitutes about half of the total phenolic content, making it a key component in many applications.
In terms of physical properties, a 20% aqueous solution of apple polyphenols appears reddish-brown, while the dry powder has a light yellow-brown color. Within normal usage levels, it does not significantly alter the color of the final product. The flavor profile of both liquid and powdered forms is slightly apple-like with a mild bitterness, which is only one-third to one-fifth as intense as that of tea polyphenols. This makes it suitable for use without affecting the taste of the product.
Apple polyphenols are also highly water-soluble, with a solubility of up to 30% at room temperature—ten times higher than that of tea polyphenols. This high solubility enhances their versatility in food and cosmetic formulations. Additionally, the powdered form remains stable for up to one year at room temperature, retaining its functional properties.
Stability tests show that apple polyphenol solutions (0.1%-1%) remain effective after heating at 100°C or 120°C for 30 minutes, with a preservation rate exceeding 80% across a pH range of 2 to 10.
Functionally, apple polyphenols offer a wide range of health benefits. They inhibit glucosyltransferase (GTase), a key enzyme involved in dental plaque formation, making them highly effective in preventing tooth decay. Compared to green tea’s EGCG, apple polyphenols are 100 times more potent in inhibiting GTase, with apple condensed tannin (ACT) being the primary anti-caries agent.
They also exhibit strong antioxidant activity, surpassing that of tea polyphenols in protecting against lipid oxidation. Apple condensed tannins act as free radical scavengers, contributing to anti-aging effects. Furthermore, they demonstrate significant anti-mutagenic and anti-cancer properties, with ACT showing stronger effects than chlorogenic acid and epicatechin. Studies have shown that apple polyphenols can suppress the carcinogenic effects of substances like benzopyrene.
Additionally, they help in managing blood pressure by inhibiting angiotensin-converting enzyme (ACE), thereby preventing vasoconstriction. Catechins, epicatechins, and apple condensed tannins all contribute to this effect, with ACT being the most active.
Due to their diverse functions—including antioxidant, preservative, deodorizing, and color-stabilizing properties—apple polyphenols are widely used in food processing, including aquatic products, meats, baked goods, oils, and beverages. They enhance product quality and extend shelf life. In addition, their health benefits make them valuable in the development of functional foods and cosmetics. At concentrations between 50–500 ppm, they provide optimal efficacy, making them a cost-effective and powerful natural additive.
Frozen Fillet Tilapia,China Tilapia Fillet,Tilapia Fillet,Tilapia Fillet Frozen Fish
Zhoushan City Shuangying Aquatic Products Co., Ltd.  , https://www.shuangying-aquatic.com