Acai and Nutrition

It's important to understand the link between acai and nutrition. It should come as no surprise to learn that Amazonian food is rich in a variety of nutrients.

Sophisticated methods of analyzing the nutritional content of the acai fruit were undertaken in the 1990's at Brazilian universities, about the same time that freeze drying methods for preserving the fruit yielded more bioactive results.

According to Dr. Alexander Schauss in his book Acai: The Nutritional & Antioxidant Rich Amazon Palm Tree Fruit, a research institute call AIBMR Life Sciences was commissioned to do more extensive work on the acai's nutritional profile, especially freeze dried acai fruit pulp, and compare that profile to other fruit and vegetables nutritional heavyweights.

According to the results from AIBMR and other reports the acai nutrient profil is quite impressive. The following are just some of the nutrients that the fruit reportedly contains:
- B vitamins (various)
- Beta carotene
- Boron
- Calcium
- Chromium
- Copper
- Folale
- Iodine
- Iron
- Magnesium
- Manganese
- Molybolenum
- Potassium
- Selenium
- Vitamin C,D,E
- Zinc

Several early studies done on the acai nutritional composition and were summarised by Rogez in a 2000 book in Portuguese entitled "Acaí: Preparo, Composição e Melhoramento de Conservação" (Schauss et al. 2006a). Other previous studies dating back to the 1930s and 40s were not always in agreement on nutritional contents.

Recent acai and nutritional study using modern procedures and a standardised freeze-dried acai fruit pulp and skin powder found the following analysis results from 100 g (3.5 ounces) of powder to equal 533.9 calories, 52.2 g carbohydrates, 8.1 g protein and 32.5 g total fat. The carbohydrate portion includes 44.2 g of fiber (Schauss et al. 2006a). Having nearly one third of its mass as dietary fiber, acai is an exceptional source of this valuable macronutrient: a 100 g serving of the powder would provide all the recommended fiber needs for adults (20-30 g per day).

Acai is particularly rich in fatty acids, feeling oily to the touch. It contains high levels of the monounsaturated fatty acid oleic acid (56.2% of total fats). It is also rich in palmitic acid (24.1% of total fats, a saturated fat) and the polyunsaturated omega-6 fatty acid linoleic acid (12.5% of total fats). (Schauss et al. 2006a). β-sitosterol (beta-sitosterol), a phytosterol that competes with dietary cholesterol for absorption and so may reduce blood cholesterol levels, is also unusually rich (78-91% of total sterols) (Lubrano, 1994; Schauss 2006a).

A later study found vitamin C content was negligible, calcium levels of 260 mg, iron to be 4.4 mg and vitamin A equal to 1002 IU per 100 g of dry weight (Schauss et al. 2006a). A recent study found 19 amino acids in pulp and skin powder, with especially high contents of aspartic acid and glutamic acid. The amino acid content totalled 7.59% of the total dry weight (Schauss et al. 2006a).

Due to the large amount of waste that accumulates during the harvesting of the hearts of palm, sawdust from the left-over trunks of the açaí palms have been analyzed for possible uses including energy utilization. The inner layer of the trunk is mineral rich, and is significantly higher in all the minerals that were tested including sodium, potassium, calcium, magnesium, and iron compared to the outer layer of the tree. This inner layer could potentially be used as a source for these minerals. Ash content (often used as an alkaline source for saponification or in plant fertilizers) was also higher in the inner section of the tree. Levels of lignins, cellulose, holocellulose and gross heat production were slightly higher in the outer trunk layers, and cellulose levels were fairly high overall (Dyer, 1996).

Fruits and Vegetables ...

Fruit and vegetables re important for good health.  They are a valuable source of vitamins, mineral, fiber and phytountirents.  Studies have documented numerous health benefits associated with eating fruits and vegetables, with the greatest benefits seen in people who consume more than the recommended daily amounts. The fact is most people from industralised countries do not eat enough fruits and vegetables.

Nutrient levels in fresh fruits and vegetables are declining

Four studies reported that today's fresh fruit and vegetables are lower in certain vitamins and minerals than they were as little as 50 years ago.  These studies compared nutrient data from as early as 1930 to as recent as 1999 for the US, the UK, and Canada.  No matter the country or the timeframe studied, the results were similar.  The vitamin and mineral contents of fruits and vegetables is decreasing.  For example two peaches would have supplied a woman's vitamin A RDA in 1951, today she would have to eat almost 53 peaches to meet this requirement!

Why are Nutrient losses occuring?

Many factors could be involved, including plant breeding practices taht select for high yield and cosmetic appeal, storage and ripening systems, and reliance on chemical fertilisers.

Cooking and processing can deplete fruits and vegetables of nutrients.  Fruit or vegetables that are boiled or canned loose at least 50 percent of their nutritional value.

References:

Hyson D. The Health Benefits of Fruits and Vegetables: A Scientific Overview for Health Professionals. Wilmington,DE: Produce for Better Health Foundation,2002.

US Department of Health and Human Sciences and US Department of Agriculture. Dietary Guidelines for Americans, 2006,6th Edition,Washington DC US Government Printing Office,2005.

Casagrande SS, Wang Y, Anderson C,et al. Have Americans increased their fruit and vegetable intake? The trends between 1988 and 2002. Am J Prev Med 2007; 32(4):257-63.

Mayer A-M. Historical changes in the mineral content of fruits and vegetables.  Brit Food J 1997; 96(6):207-11.

Christian J. Charts: Nutrient changes in vegetable and fruits, 1951 to 1999. CTV.ca News 2002.

Davis DR. Epp MD, Riordan HD. Changes in USDA Food Composition for 43 Graden Crops, 1950 to 1999. J AM C Nutr 2004; 23(6):669-82

Thomas D.A Study on the mineral depletion of the foods available to us as a nation over the period of 1940 to 1991. Nutr Health 2003; 17(2):85-115.

Souci SW, Fachmann W, Kraut H. Food Compostition and Nutrition Tables, 6th Edition, Boca Raton, FL:CRC Press 2000.