Breaking News on Supplements, Health & Nutrition - Europe US edition | APAC edition

News > Research

Read more breaking news



The Apple Tree of Life? Adding leaves to juice boosts health potential: Study

By Ben Bouckley+

Last updated on 05-Feb-2013 at 15:12 GMT2013-02-05T15:12:06Z

Picture Copyright: Alessio Maffeis/Flickr
Picture Copyright: Alessio Maffeis/Flickr

Adding apple tree leaves to cloudy apple juice to boost polyphenol content could prove a reliable and cheap way for manufacturers to produce functional beverages with disease-preventing potential, according to a new Polish study.

As common constituents in the human diet, with fruits and vegetables as the major dietary source, polyphenols are organic chemicals with a range of potential health benefits due to antioxidant and anti-inflammatory properties, with recent animal studies, for instance, showing protective activity with respect of carcinogenesis.

Apples are particularly high in polyphenols, and as Kolniak-Ostek et al. write in this study: “Cloudy apple juice, one of the most common components of fruit intake in Europe, may play an important role in maintaining human health. Phytochemicals of fruit juices have strong antioxidant and anti-proliferative properties.

Harsh processing techniques

But Kolniak-Ostek et al. (from Wroclaw University of Environmental and Life Sciences, Poland) wrote that apple juice processing techniques meant that the loss of 50-90% of healthy polyphenols was unavoidable (Dietrich et al. 2003), before suggesting that adding apple leaves to beverages could make a big difference.

 “The addition of apple leaves to the cloudy apple beverages may increase polyphenols’ concentrations as compared to the cloudy apple juice,” the scientists said, adding that they wanted to focus on producing such juices with added leaves to explore this possibility.

The study authors explained that apple tree leaves – those they tested were of the Sampion apple tree variety – were rich in phytochemicals, especially flavonoids (the largest family of polyphenolic compounds) and polyphenols, and were of interest due to their “important biological and pharmacological properties”.

“Until now, the use of leaves from fruit trees have not generally received much attention as the sources of antioxidants and this could have happened due to their lack of popularity and lack of commercial applications,” Kolniak-Ostek et al. said, adding that fruit leaves had nonetheless been used in folk medicine.

Previous research (Wang and Lin, 2000) indicated that strawberry, black- and red raspberry and strawberry plants had higher antioxidant capacities and total phenolic content compared to their fruit tissues, Kolniak-Ostek et al. wrote.

‘Good and cheap’ bioactive source

More specifically, the scientists noted a 2007 paper by Renard et al., indicating that apple fruit leaves could be used as a “good and cheap source of bioactive constituents with potential use in industry”.

In the current study, Kolniak-Ostek et al. found that the total phenolic compound content in fortified juices – between 1665 mg per liter (mg/l) and 2541mg/l – was higher than a control apple juice (440mg/l), with antioxidant capacity positively correlated with polyphenolic compound content.

“This study suggests that the use of apple tree leaves can be a better and cheaper source of bioactive compounds and may have relevance in the prevention of diseases in which free radicals are implicated, Kolniak-Ostek et al. added.

Leaves were rich in phytochemicals – especially flavonoids and phenolic acids, and were of interest for their “important biological and pharmacological properties”, the team wrote.

“The results demonstrated that cloudy apple beverages, produced with addition of 0.5%, 1%, and 5% of apple leaves can be a valuable food products.

“Additionally, leaves had positive effect on the increase of phytochemicals, especially flavan-3-ols [polyphenols] and flavonols, and antioxidant capacity,” Kolniak-Ostek et al. added.

Title: ‘Effect of apple leaves addition on physicochemical properties of cloudy beverages’

Authors: Kolniak-Ostek, J., Oszmianski, J., Wojdylo, A.

Source: Industrial Crops and Products, January 2013, pp.413-420,

Related products

Live Supplier Webinars

Polyphenols tipped to become the way to innovate in Sports Nutrition
Orally bioavailable standardized botanical derivatives in sport nutrition: special focus on recovery in post-intense physical activities
Collagen in motion: move freely and keep your injuries in check
Leading manufacturer of gelatine and collagen peptides
Life’s too short for slow proteins. Whey proteins hydrolysates: Fast delivery for enhanced performance
Arla Foods Ingredients
What it Takes to Compete and Win in Today’s Sports Nutrition Market
Sports Nutrition Snapshot: Key regional drivers and delivery format innovations
William Reed Business Media
Gutsy performance: How can microbiome modulation help athletes and weekend warriors
William Reed Business Media
Pushing the boundaries: Where’s the line between ‘cutting edge nutrition’ and doping
William Reed Business Media
Alpha & Omega in Sports Nutrition – Using Omega 3’s and A-GPC to improve performance and recovery.
KD Pharma

On demand Supplier Webinars

High-amylose maize starch may reduce the risk of type 2 diabetes: what does this qualified health claim mean?
Balancing Innovation and Risk in Sports Nutrition Ingredients
Explaining bio-hacking: is there a marketing opportunity for food companies?
William Reed Business Media
Personalized Nutrition – how an industry can take part in shaping the future of Nutrition
BASF Nutrition & Health
Find out Nutritional and ingredient lifecycle solutions and strategies!
Is the time rIpe for I-nutrition?
William Reed Business Media
The Advantage of Outsourcing Fermentation-based Manufacturing Processes
Evonik Health Care
All supplier webinars