EXOTIC VS COMMON FRUIT

Persimmon

The other day, I ventured out grocery shopping with a very particular goal in mind: find exotic fruit I have not yet tasted and explore their nutritional value. I was curious to know how aromatic Mexican guavas, tart Colombian tamarillos and sweet Taiwanese rambutans compared with more common fruit and whether there were nutritional benefits to seeking out these strangely named foods.

I theorized that although exploring exotic fruit can be intriguing, all essential vitamins and minerals could be easily obtained from foods commonly grown and consumed in Canada. From time to time, I hear of so-called super foods with alluring names and unique nutritional properties that are heavily marketed as the solution to weight loss and every other human health issue. However, worshiping any one particular food is fundamentally erroneous, as it devalues more common alternatives and negates the supreme benefits of a varied diet.

In the recent months, Loblaw's Real Canadian Superstore has been doing a great job stocking its shelves with more organic and exotic produce, so it became my first destination.  Marcus in the driver's seat of a large shopping cart, we headed straight for the store's produce section and were immediately welcomed by a large box full of ripe pomegranates. During the third trimester of my pregnancy with Marcus, I found myself craving the blood-red seeds of this fruit so much that I treated myself to at least one per day for several weeks. But although very nutritious and less common than apples, pomegranates, grown as close to BC as California, were not foreign enough for the purpose of this comparison.

Rambutan

Moving forward through the fruit isles, I came across red papayas, carambola (starfruit), persimmons, pitahaya (dragon fruit) and prickly pears, the latter being the only fruit I have not tasted and knew precious little about. I loaded my cart with several representatives of the above species, paid at the till and headed for Choices Market- the BC chain of natural and gourmet food stores. At Choices, I found guavas, rambutans and tamarillos, neither of which had the misfortune of getting butchered in my kitchen before.

In order to compare the fruit, I decided to create two separate tables- one for vitamins and another one for minerals- obtain the necessary data through USDA's National Nutrient Database for Standard Reference and compare it with the RDA (Recommended Dietary Allowance) specified in Health Canada's Dietary Reference Intakes Tables. All seemed rather straight forward until I got to work on populating table cells and realized that data on exotic fruit like tamarillos were either limited or altogether absent from the Nutrient Database and had to be obtained from alternative, often multiple, sources. 

All in all, I utilized nine unique sources of data to build three tables, one of which specified ORAC (Oxygen Radical Absorbance Capacity) value of individual fruits, although I was unable to obtain it for four of twelve items. In essence, this measures antioxidant activity of various foods, and since vitamins are not the only compounds with antioxidant properties, the decision was made to include it as another way to compare the nutritional value of chosen fruit.

Fruit	Energy (kcal)	Fibre (g)	Sugars (g)	Vitamin A (IU)	Vitamin E (mg)	Vitamin K (µg)
EXOTIC FRUIT
Guava	68	5.4	8.92	324	0.73	2.6
Papaya	43	1.7	7.82	950	0.30	2.6
Persimmon	70	3.6	12.53	1627	0.73	2.6
Pomegranate	83	4.0	13.67	0	0.60	16.4
Prickly Pear	41	3.6	9.57	43	0	0
Lychee	66	1.3	15.23	0	0.07	0.4
Starfruit	31	2.8	3.98	61	0.15	0
Tamarillo	33.5	3.45	3.85	630	1.95	0
COMMON FRUIT
Apple, Gala	57	2.3	10.37	28	0.18	0
Banana	89**	2.6	12.23	64	0.10	0.5
Orange, Navel	49	2.2	8.50	247	0.15	0
Pear, Bartlett	63	3.1	9.69	28	0.12	3.8
RDA*	2481	25	N/A	2333	15	90

*Figures provided are RDA or AI (Adequate Intake), where RDA is not available

**Figures in bold red indicate the highest values in the category

Due to difficulties obtaining nutritional data on particular fruits, they were replaced by similar varieties. For example, a rambutan was replaced with its close relative, lychee (litchi), and a native persimmon gave way to the Japanese (Oriental) variety. After some hesitation, I also included a pomegranate, simply to compare its vitamin K content with that of other fruit. Having been aware of its importance in calcium absorption and coagulation, or blood clotting, ever since my pregnancy with Marcus, I resolved to add it to the list of exotics.

Fruit	Vitamin C (mg)	Thiamin (Vitamin B1) (mg)	Riboflavin (Vitamin B2) (mg)	Niacin (Vitamin B3) (mg)	Vitamin B6 (mg)	Folate (Vitamin B9) (µg)
EXOTIC FRUIT
Guava	228.3	0.067	0.040	1.084	0.110	49
Papaya	60.9	0.023	0.027	0.357	0.038	37
Persimmon	7.5	0.030	0.020	0.100	0.100	8
Pomegranate	10.2	0.067	0.053	0.293	0.075	38
Prickly Pear	14	0.014	0.060	0.460	0.060	6
Lychee	71.5	0.011	0.065	0.603	0.100	14
Starfruit	34.4	0.014	0.016	0.367	0.017	12
Tamarillo	32.05	0.043	0.010	0.271	0.390	4
COMMON FRUIT
Apple, Gala	0	0.017	0.029	0.075	0.049	0
Banana	8.7	0.031	0.073	0.665	0.367	20
Orange, Navel	59.1	0.068	0.051	0.425	0.079	34
Pear, Bartlett	4.4	0.012	0.026	0.164	0.026	0
RDA*	75	1.1	1.1	14	1.3	400

*Figures provided are RDA or AI (Adequate Intake), where RDA is not available

**Figures in bold red indicate the highest values in the category

Guava

Fruit	ORAC (TEAC)
EXOTIC FRUIT
Guava	1018
Papaya	300
Persimmon	Unknown
Pomegranate	4479
Prickly Pear	Unknown
Lychee	Unknown
Starfruit	Unknown
Tamarillo	1659.4
COMMON FRUIT
Apple, Gala	2828
Banana	795
Orange, Navel	1819
Pear, Bartlett	1746*

Having considered all vitamin values, I determined that Mexican guava was a definite winner in four categories: fibre, vitamin C, niacin and folate content. At $3.98 per package of 600 grams, it is one of the less expensive exotic fruit and worth considering as a healthful addition to one's diet. By the same token, fibre, vitamin C and B-group (except from B12) vitamins can be obtained from other plant sources. For instance, vegetables like broccoli and Bell peppers are high in vitamin C and are significantly less costly. 

Fruit	Calcium (mg)	Copper (µg)	Iodine (µg)	Iron (mg)	Magnesium (mg)	Manganese (µg)
EXOTIC FRUIT
Guava	18	0.2	0	0.26	22	200
Papaya	20	0	0	0.25	21	0
Persimmon	8	0.1	0	0.15	9	400
Pomegranate	10	0.2	0	0.30	12	100
Prickly Pear	56	0.1	0	0.30	85	0
Lychee	5	0.1	0	0.331	10	100
Starfruit	3	0.1	0	0.08	10	0
Tamarillo	12.6	0.086	0	0.445	22.3	149.5
COMMON FRUIT
Apple, Gala	7	0	0	0.12	5	0
Banana	5	0.1	0	0.26	27	300
Orange, Navel	43	0	0	0.13	11	0
Pear, Bartlett	9	0	0	0.19	6	0
RDA*	1000	900	150	18	310	1800

*Figures provided are RDA or AI (Adequate Intake), where RDA is not available

**Figures in bold red indicate the highest values in the category

Tamarillo

Fruit	Molybdenum (µg)	Phosphorus (mg)	Selenium (µg)	Zinc (mg)	Potassium (mg)	Chloride (mg)
EXOTIC FRUIT
Guava	0	40	0.6	0.23	417	0
Papaya	0	10	0.6	0.10	182	0
Persimmon	0	17	0.6	0.11	161	0
Pomegranate	0	36	0.5	0.35	236	0
Prickly Pear	0	24	0.9	0.12	220	0
Lychee	0	31	0.6	0.07	171	0
Starfruit	0	12	0.6	0.12	133	0
Tamarillo	1.2	36.95	0.1	0.16	408	0
COMMON FRUIT
Apple, Gala	0	11	0	0.05	108	0
Banana	0	22	1.3	0.15	358	0
Orange, Navel	0	23	0.7	0.08	166	0
Pear, Bartlett	0	11	0	0.08	101	0
RDA*	45	700	55	8	4700	3600

*Figures provided are RDA or AI (Adequate Intake), where RDA is not available

**Figures in bold red indicate the highest values in the category

Prickly Pear

The mineral content in chosen fruit confirmed guava to as a superior source of food among its eleven rivals. It was also revealed that a prickly pear is by far the richest source of calcium, magnesium and selenium and at approximately $1.25 per pear, it might be worth purchasing from time to time. That is if one appreciates its unusual taste of a watermelon and bubblegum. 

However, once again, the elements and anthocyanins (phytochemicals with antioxidant properties) it contains can be obtained from alternative plant sources. It is also important to mention that micronutrient content of fruit varies depending upon the growing region, whether the fruit was picked ripe or not, how long it spent in storage and exactly what subspecies is being considered. 

Therefore, there is no way of knowing precisely what is contained in any particular fruit at any given time. Neither is it realistic or necessary to remember nutrient content of every edible plant. Instead, adopting a varied diet with plenty of colour, taste and texture differences will ensure a full spectrum of macro and micronutrients for ultimate health.

Cited Sources:
http://www.princetonlivingwell.com/calculators/eer.aspx
http://www.hc-sc.gc.ca/fn-an/nutrition/reference/table/ref_macronutr_tbl-eng.php
http://www.hc-sc.gc.ca/fn-an/nutrition/reference/table/ref_vitam_tbl-eng.php
http://www.hc-sc.gc.ca/fn-an/nutrition/reference/table/ref_elements_tbl-eng.php
http://ndb.nal.usda.gov/ndb/foods
http://www.rambutan.com/Nutrition.html
The Nutritional Composition and Health Benefits of New Zealand Tamarillos, C. E. Lister, S. C. Morrison, N. S. Kerkhofs & K. M. Wright
New Zealand FOODFiles 2012 Version 01
http://www.oracvalues.com/
http://www.lenntech.com/about/aboutlenntech-en.htm
http://nutritiondata.self.com/
http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/herbsvitaminsandminerals/phytochemicals
http://umm.edu/health/medical/altmed/supplement/vitamin-k