Apples and Applesauce Recipe
Subject: Phytochemicals in apples provide anticancer and antioxidant
benefits
Time to adjust an old adage: It's the phytochemicals in the apple each day
that keep the doctor away.
A combination of plant chemicals, such as flavanoids and polyphenols --
collectively known as phytochemicals -- found both within the flesh of
apple and particularly in the skin -- provide the fruit's antioxidant and
anticancer benefits according to a study published in the journal Nature.[1]
Although it has long been known that apples provide anti-oxidant and health
benefits, "this concept is different," says Rui Hai Liu, Cornell assistant
professor of food science and lead author on the Nature article,
"Anti-oxidant activity of fresh apples."
Says Liu: "Scientists are interested in isolating single compounds -- such
as vitamin C, vitamin E and beta carotene -- to see if they exhibit
anti-oxidant or anti-cancer benefits. It turns out that none of those works
alone to reduce cancer. It's the combination of flavonoids and polyphenols
doing the work."
An antioxidant is one of many chemicals that reduce or prevent oxidation,
thus preventing cell and tissue damage from free radicals in the body.
"In this research, we have shown the importance of phytochemicals to human
health," says Liu's collaborator, Chang Yong Lee, Cornell professor of food
science. "Some of the phytochemicals are known to be antiallergenic, some
are anticarcinogenic, anti-inflammatory, antiviral, antiproliferative. Now
I have a reason to say an apple a day keeps the doctor away."
The researchers found that vitamin C in apples is only responsible for a
small portion of the anti-oxidant activity. Instead, almost all of this
activity in apples is from phytochemicals. The researchers found that
eating 100 grams of fresh apple with skins provided the total anti-oxidant
activity equal to 1,500 milligrams of vitamin C.
"Eating fruits and vegetables is better than taking a vitamin pill." says
Liu. "You can obtain enough antioxidants from food without worrying about
toxicity. What this study shows is the combination of phytochemicals plays
a very important role in antioxidant and anticancer activity, and the real
health benefits may come from a phytochemical mixture."
The researchers used red delicious apples grown in New York State to
provide the extracts to study the effects of phytochemicals. The
researchers compared the anticancer and antioxidant activity in the apple
flesh, and they also studied the fruit's skin.
Using colon cancer cells treated with apple extract, the scientists found
that cell proliferation was inhibited. Colon cancer cells treated with 50
milligrams of apple extract (from the skins) were inhibited by 43 percent.
The apple flesh extract inhibited the colon cancer cells by 29 percent.
The researchers also tested the apple extract against human liver cancer
cells. At 50 milligrams, the extract derived from the apple with the skin
on inhibited those cancer cells by 57 percent, and the apple extract
derived from the fruit's fleshy part inhibited cancer cells by 40 percent.
"The consumption of whole fruits may provide the balanced antioxidants
needed to quench reactive oxygen species," write the researchers in the
Nature article. "Phytochemicals other than ascorbic acid (vitamin C) ...
contribute significantly to the anti-oxidant activity of apples and to the
capacity to inhibit tumor cell proliferation."
As mentioned in prior newsletters, it appears that processing (the word
food scientist's such as Dr. Liu use rather than cooking) does not lower
the antioxidant activity of apples. Best predictions suggest that cooking
will increase it.
The September/October issue of Cook's Illustrated feature's an article on
how to make applesauce. Homemade applesauce is easy provided that you own
the right tool and choose the right apples.
First, the right tool. In this case it is a gadget called a Food Mill. It
looks like a sieve with a crank on top. The hand crank rotates a gently
curved blade that catches the food and forces it through the sieve. Making
applesauce is simply a matter of boiling the apples, skins, cores, and all
in a pot until tender and then processing through the food mill. Cooks
Illustrated kindly tested various Food Mills sold and rated them. Of
course they found little to complain about with the $90 Cusipro from
Cuisinart but they admitted that the $15 Mill made by Moulinex "did nearly
as well."
I did heft the Cusipro at the Williams Sonoma Store at the Cherry Creek
Mall with a covetous gleam in my eye, before I went to Sur Le Table to buy
the Molinex for $18.
If you don't use a food mill to make applesauce you must core and peel the
apples before cooking. As most of the phytochemicals we are interested in
are in the skins this is unacceptable. Leaving the skins on the apples is
another option but does not work well in households with children.
The second trick to making good applesauce is using the right apples. I
made the mistake with my first batch of ignoring Cook's Illustrated and
used Braeburns. My applesauce came out just as the magazine said it would,
"odd (and) plasticky."
The best apples to use are Jonagold, Jonathan, Pink Lady and Macoun.
Other apples that work are Golden Delicious, Empire, Mcintosh and Rome. It
seems that the rest of the good eating apples make for lousy applesauce. Do
not use Granny Smith, Braeburns, Cortlands or Idared.
Simple Applesauce (adapted from Cook's Illustrated)
4 pounds of apples (8-12) preferably jonagold, Pink Lady, Jonathan, or
Macoun. unpeeled, and cut into rough chunks
1 cup water
pinch of salt
up to 1/4 cup sugar (if you must)
Toss the apples in a heavy bottomed kettle, cover and cook for 15-20
minutes until they break down. Process through the food mill and season
and sweeten to taste. It's that easy.
If you read Cook's Illustrated you know they are fanatical, almost
obssesive about food. They prefer their applesauce plain and unadulterated
with other flavors. To their food tasters, using a little honey in place
of the sugar overpowered the true flavor of the sauce. But if you would
like to increase the nutritional benefit of your sauce there are a few
embellishments you might wish to add:
Cinnamon: a few sticks cooked with the apples and removed before milling
Cranberrys: add one cup fresh or frozen to the apples during cooking and
puree with the apples
Ginger: 2-3 1/2 inch slices cooked with the apples and removed before
pureeing
Lemon: 1 teaspoon of zest cooked and pureed with the apples.
References:
1. MARIAN V. EBERHARDT, CHANG YONG LEE & RUI HAI LIU Nutrition:
Antioxidant activity of fresh apples Nature 405, 903 - 904 (2000).
Abstract:
Vitamin C is used as a dietary supplement because of its antioxidant
activity, although a high dose (500 mg) may act as a pro-oxidant in the
body. Here we show that 100 g of fresh apples has an antioxidant activity
equivalent to 1,500 mg of vitamin C, and that whole-apple extracts inhibit
the growth of colon- and liver- cancer cells in vitro in a dose-dependent
manner. Our results indicate that natural antioxidants from fresh fruit
could be more effective than a dietary supplement.
2. Sun J, Chu YF, Wu X, Liu RH. Antioxidant and Antiproliferative
Activities of Common Fruits.. J Agric Food Chem 2002 Dec 4;50(25):7449-7454
Consumption of fruits and vegetables has been associated with reduced risk
of chronic diseases such as cardiovascular disease and cancer.
Phytochemicals, especially phenolics, in fruits and vegetables are
suggested to be the major bioactive compounds for the health benefits.
However, the phenolic contents and their antioxidant activities in fruits
and vegetables were underestimated in the literature, because bound
phenolics were not included. This study was designed to investigate the
profiles of total phenolics, including both soluble free and bound forms in
common fruits, by applying solvent extraction, base digestion, and
solid-phase extraction methods. Cranberry had the highest total phenolic
content, followed by apple, red grape, strawberry, pineapple, banana,
peach, lemon, orange, pear, and grapefruit. Total antioxidant activity was
measured using the TOSC assay. Cranberry had the highest total antioxidant
activity (177.0 +/- 4.3 &mgr;mol of vitamin C equiv/g of fruit)!
, followed by apple, red grape, strawberry, peach, lemon, pear, banana,
orange, grapefruit, and pineapple. Antiproliferation activities were also
studied in vitro using HepG(2) human liver-cancer cells, and cranberry
showed the highest inhibitory effect with an EC(50) of 14.5 +/- 0.5 mg/mL,
followed by lemon, apple, strawberry, red grape, banana, grapefruit, and
peach. A bioactivity index (BI) for dietary cancer prevention is proposed
to provide a new alternative biomarker for future epidemiological studies
in dietary cancer prevention and health promotion.
J Agric Food Chem 2002 Nov 6;50(23):6910-6
Antioxidant and antiproliferative activities of common vegetables.
Chu YF, Sun J, Wu X, Liu RH.
Epidemiological studies have shown that consumption of fruits and
vegetables is associated with reduced risk of chronic diseases. Increased
consumption of fruits and vegetables containing high levels of
phytochemicals has been recommended to prevent chronic diseases related to
oxidative stress in the human body. In this study, 10 common vegetables
were selected on the basis of consumption per capita data in the United
States. A more complete profile of phenolic distributions, including both
free and bound phenolics in these vegetables, is reported here using new
and modified methods. Broccoli possessed the highest total phenolic
content, followed by spinach, yellow onion, red pepper, carrot, cabbage,
potato, lettuce, celery, and cucumber. Red pepper had the highest total
antioxidant activity, followed by broccoli, carrot, spinach, cabbage,
yellow onion, celery, potato, lettuce, and cucumber. The phenolics
antioxidant index (PAI) was proposed to evaluate the quality/quantity !
of phenolic contents in these vegetables and was calculated from the
corrected total antioxidant activities by eliminating vitamin C
contributions. Antiproliferative activities were also studied in vitro
using HepG(2) human liver cancer cells. Spinach showed the highest
inhibitory effect, followed by cabbage, red pepper, onion, and broccoli. On
the basis of these results, the bioactivity index (BI) for dietary cancer
prevention is proposed to provide a simple reference for consumers to
choose vegetables in accordance with their beneficial activities. The BI
could be a new alternative biomarker for future epidemiological studies in
dietary cancer prevention and health promotion.
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