Cranberry Research Findings

CRANBERRIES

Cranberry Research Notes

MAINE:
FINAL Results of 1998-2000 SARE Grower Grant
("An Alternative to the Winter Protection of Cranberries in Maine")
*********************************
SUMMARY OF CRANBERRY FRUITWORM COVER STUDY
CONDUCTED IN 2003 AND 2004 AT SPARROW FARMS IN PITTSTON, MAINE
Key Question: Are enough cranberries protected from cranberry fruitworm by using a polypropylene fabric
row cover to justify the expense of the cover?

ELSEWHERE:

Notes gathered from past cranberry workshops and conferences:

Massachusetts:

UMass Cranberry Management Update - Jan. 2009, Plymouth. MS Word (533 Kb) || pdf (282 Kb)
Sanding and Pruning Differentially Impact Cranberry Yield and Canopy Characteristics – by Carolyn DeMoranville – Aug. 9th, NACREW Conference, Moncton, NB. MS Word (50.5 Kb) || pdf (53.1 Kb)

CANADA:
March 2008 - Atlantic Cranberry Course - Prince Edward Island. MS Word (555 Kb) || pdf (392 Kb)
April 2006 - Atlantic Cranberry Course - Fredericton, NB. MS Word (57.5 Kb) || pdf (158 Kb)

Summaries of some Published Cranberry Research:
Phenol Antioxidant Quantity and Quality in Foods: Fruits
Dietary Intake of Antioxidants and Reduced Risk of Alzheimer Disease (2 JAMA studies)
Ice Nucleation and Propagation in Cranberry Uprights and Fruit Using Infrared Video Thermography

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
November, 2001. Vol. 49, No. 11:
Phenol Antioxidant Quantity and Quality in Foods: Fruits

NOTES:

Lead researcher, Vinson, and his team have recently shown that many phenols and polyphenols are stronger antioxidants than are vitamin antioxidants (using as a model the oxidation of the lower density lipoproteins LDL+VLDL)
For this study, they looked at phenol content in 20 different fruits commonly consumed in America: apple, avocado, banana, blueberry, cantaloupe, cherry, cranberry, grape (both red and white), grapefruit, lemon, honeydew, nectarine, orange, peach, pear, pineapple, plum, strawberry and watermelon.
For the study, 2 or 3 samples of fresh fruits were obtained from local supermarkets.
The polyphenol concentration of the fruits was measured as both free and total phenols. Only a few fruits--avocado, cranberry, honeydew melon, and orange--were found to have a large portion of their phenols in a free form (versus conjugated, as in the other fruits). Cranberries, by far, had the largest amount of both free and total phenols among the 20 fruits tested, with red grapes a distant second. The rankings are as follows: cranberry (1), red grape (2), banana (3), cherry (4), blueberry (5), plum (6), white grape (7), pear (8), apple (9), strawberry (10), avocado (11), peach (12), lemon (13), pineapple (14), watermelon (15), nectarine (16), orange (17), honeydew melon (18), cantaloupe (19), and grapefruit (20) -- I knew there was a reason why I don't like grapefruit!!
However, when Vinson and his team used a different method of measuring antioxidant quantity, called the oxygen radical assay (ORAC), blueberry came out the winner, and cranberry was somewhat less. Nevertheless, Vinson comments that although the two different methods yield different values for different fruits and vegetables, they still match up pretty closely with each other.
Vinson and his team also compared the 20 fruits on the basis of serving size, and when they did this, cranberry once again came out on top, followed by pear, red grape, apple, blueberry & watermelon (equal), banana & strawberry (equal), white grape, and plum, in that order.
Besides the important discovery of just how much phenol content there is in cranberry, another good take-home message from this study is that, in general, berries had the better quantity, and better quality, of antioxidants among the fruits tested, and that fruit phenols were significantly better antioxidants than were vegetables (p < 0.005)!

JAMA - June 26, 2002
The Journal of the American Medical Association

The consistency of findings in these two independent cross-national studies is notable. The similarity of the results, which were generated using similar, standardized methods in Chicago (US) and Rotterdam (The Netherlands), provides persuasive support for the idea that antioxidant-rich foods may have a beneficial impact on the development of Alzheimer's disease. Several previous findings suggest that oxidative stress may play an important role in the development of Alzheimer disease, which is now the 4th-leading cause of death among adults, and is expected to afflict an estimated 14 million people within the next 50 years, leading some to call it the "health care challenge of the 21st century!" In the United States, the current estimate of 360,000 new cases of Alzheimer's each year is expected to triple in the next 40 years! Even modestly effective interventions that delay the onset of this terrible disease by one to three years will substantially alleviate its growing economic and societal burden.

1). Dietary Intake of Antioxidants and Risk of Alzheimer Disease (pages 3223-3229)
M. J. ENGELHART, M. I. GEERLINGS, A. RUTTENBERG, J. C. VAN SWIETEN, A. HOFMAN, J. C. M. WITTEMAN, M. M . B. BRETELER
2). Dietary Intake of Antioxidant Nutrients and the Risk of Incident Alzheimer Disease in a Biracial Community Study (pages 3230-3237)
MARTHA C. MORRIS (ScD), DENIS A. EVANS (MD), JULIA. L. BIENIAS (ScD), CHRISTINE C. TANGNEY (PhD), DAVID A. BENNETT (MD), NEELUM AGGARWAL (MD), ROBERT S. WILSON (PhD), PAUL A. SCHERR (PhD, ScD)

In both of these observational studies, higher dietary intake of antioxidants--especially vitamin E--was found to be associated with a lower risk of incident Alzheimer Disease (AD). The result was less clear, overall, with vitamin C. In the Chicago Health and Aging Project, persons in the highest category of vitamin E intake from food were 70% less likely than those in the lowest category of intake to be diagnosed with AD! The overall Chicago findings for vitamin C--which cranberries are very high in--were not statistically significant in this study but remain suggestive enough to be of interest for further study. The Chicago findings were based on new cases developing in an average 3.9-year interval between the baseline and follow-up examination among 815 men and women, black and white, aged 65 years and older. Rotterdam Study: In the Rotterdam Study, persons in the highest category of vitamin E intake from food were 43% less likely to develop AD compared with those in the lowest category of intake. High intake of vitamin C had a borderline significant association with risk of AD in all models. But when additional adjustments were made for education, smoking habits, pack-years of smoking, body mass index, total energy intake, presence of carotid plaques, and use of antioxidative supplements, high intake of vitamin C was found to be significantly related to reduced risk of AD. Men in this study tended to have a higher intake of vitamin E, fat and beta carotene, and a lower intake of vitamin C as compared with the women in the study. The findings in this study were based on an average follow-up period of 6 years among 5,395 men and women aged 55 years and older.

SIDENOTES: Flavonoids are phenolic plant pigments, with high anti-oxidative power within the human body. Ripe, RED cranberries are understandably high in flavonoid content, and are the 1st of 3 flavonoid examples cited in the Rotterdam study, page 3224!! The other two are green & black tea, and pulses. For smokers in this study, beta carotene and flavonoids also seemed to have a protective effect.

JOURNAL OF THE AMERICAN SOCIETY FOR HORTICULTURAL SCIENCE
November, 1999. Vol. 124, No. 6:
Ice Nucleation and Propagation in Cranberry
Uprights and Fruit Using Infrared Video Thermography

NOTES:

"Freezing injury can occur in plants only after the formation of ice within their tissues" (619).
Infrared (IR) thermography can be used to study the location of ice formation as well as the direction and rate of ice propagation.
Ice formation in plants can be induced by either internal or external sources.

The cuticle on the upper surface of cranberry leaves appears to provide an adequate barrier to ice propagation.
Stomata, which are on the under surface (abaxial) of cranberry leaves, appear to be the likely path through which ice penetrates into cranberry leaves (Stomata are very small openings in the epidermis of a leaf or stem through which gases and water vapor pass -- singular = "stoma").
Young cranberry leaves have little to no cuticle development, and thus have been found in the past to be sensitive to any temperatures below 0 degrees C (or 32 degrees F).

In all of the fruit experiments that were done (both attached and detached fruit), ice formation within the fruit tissue was only initiated at the calyx (distal) end of the berries. This is probably because they observed stomata in the remnant area of the nectary, and since stomata are possible avenues of ice penetration into leaves, the same situation may exist for the fruit.
Air temperatures when fruit tissue began to freeze ranged from -4 to -8 degrees C (or 24.8 to 17.6 degrees F). "Red (ripe) berries supercooled typically to colder temperatures and for longer durations than blush or white (unripe) berries" (623). Most of the unripe berries (92%) began to freeze internally within 20 minutes of the surface droplets freezing, versus just one red berry (8%). 67% of the red berries never froze internally over the entire durations of the experiments (greater than or equal to one hour following the freezing of the surface water droplets).

Notes for this page taken and posted by Charles Armstrong
Univ. of Maine Cooperative Extension's Cranberry Professional

If you have comments or questions about this page,
contact Charles Armstrong at: charlesa@umext.maine.edu

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