We are supposed to “eat the rainbow” — or fill our plates with colorful food — for health reasons, and lately much attention has been focused on a particular band in that rainbow.
Purple is the “violet” in the mnemonic we learned when we were taught the colors in a rainbow. Remember ROYGBIV (red, orange, yellow, green, blue, indigo and violet)?
Whole Foods Market cited purple food as among culinary trends predicted to expand in 2017.
“We’re seeing across all kinds of produce that purple varieties are increasingly popular, along with specific varietals,” said Kevin Doty, senior global produce coordinator for Whole Foods Market. “Some of our customers’ favorites include purple cauliflower, purple asparagus, purple Stokes sweet potatoes (a patented variety), purple artichokes, purple/red kale and varietal eggplants.”
So what is the root of purple’s power?
“Specifically, what makes most of the purple foods purple are compounds called anthocyanins,” said nutritionist Alan Titchenal.
Studies on mice have found that the colorful compounds helped reduce obesity. Mice put on high-fat diets who also were given anthocyanin supplements didn’t get as fat as they otherwise would have, Titchenal said.
“There also seems to be a link, some link, possibly reducing the risk of diabetes, but bearing in mind that it’s interesting when you see them in an animal (testing) model, but to translate that to human health is a big step.”
Going back centuries, anthocyanin-rich food was used to make extracts to treat high blood pressure, fever, liver problems, urinary and excretory problems, even the common cold, according to researchers. More recent studies have confirmed benefits including protection from liver injuries, lowering blood pressure and better eyesight, as published in the Journal of Biomedicine and Biotechnology.
Purple food goes way beyond sweet potatoes and eggplant, although those tend to be top of mind when the subject is brought up.
Markets also carry purple tomatoes, cauliflower, cabbages, onions — and don’t forget taro and its primary byproduct, poi.
There are also purple and black varieties of rice, which turn indigo to dark purple after cooking.
Deep purple acai is everywhere, served in bowls with fresh fruit, and it can be purchased frozen, whole or pureed in certain grocery stores.
Jaboticaba could be considered a homegrown equivalent. The shiny, dark berry grown on Hawaii island “tastes kind of like a sour combination of Concord grape and blueberries, but sweetened up, it’s fantastic,” said Frank Gonzales, coordinator of the culinary Continuing Education program at Kapiolani Community College.
“OnoPops does an amazing jaboticaba pop,” Gonzales said.
Shin Ho, operations manager for Ho Farms, named eggplants; two varieties of small, purplish tomatoes; purple-streaked turnips; and fuchsia-toned watermelon radish as among her crops that reflect the violet spectrum.
During a recent tour of Ho Farms’ Ewa acreage, she quickly spotted some small black cherry tomatoes — actually a dark purple — and another variety of elongated, purplish grape tomatoes, both growing among the bushy tomato plants. She pulled up carrots she could tell would be purple based on their stem color, even though their tops were green.
A deep purple variety of haricots verts, also among Ho Farms’ crops, could tempt even those who hate green beans.
It’s important not to let purple’s trendiness run away with your diet, Titchenal cautioned.
“People tend to get on these ‘I’m just going to eat all this purple stuff now’” mindsets, he said. “Too much of anything in a diet can eventually be a problem.”
Blueberries, for example, are rich in anthocyanins and also are high in the mineral manganese, an essential nutrient, Titchenal said. “But if you get too much of it, it becomes a neurotoxin.”
The damage takes time to become apparent, but people overexposed to manganese in, say, an industrial setting, develop Parkinson’s disease-like symptoms, he said.
His best advice: “Don’t put all your eggs in the purple basket.” Or in any one color basket, for that matter.
He sees the eat-the-rainbow suggestion as reasonable. “All these different colorful foods have their own unique and different benefits.”
FROM THE PURPLE PRODUCE BASKET
Eggplant: The ubiquitous eggplant can be almost perfectly round, large and oblong, long and tubular, stubby and egg-shaped, or petite and curved with a bulbous end. Colors range from white to a purple so dark it’s almost black, to reddish-purple, to green, to pastel-lavender-striped. Eggplant lends itself to many cooking preparations throughout Hawaii’s ethnic cuisines — breaded and fried, stir-fried or roasted.
Potatoes: In addition to being nutritionally superior to white potatoes, purple potatoes (also known as blue potatoes) — as well as white-skinned Okinawan and Molokai sweet potatoes — add a pop of color to dishes. Wee purple potatoes are often packaged with other colorful potatoes, but a bag of all-purples can be found at Foodland Farms at Ala Moana Center.
Carrots: Some purple-skinned carrots are purple all the way through, while others are orange, yellow or white inside, or some combination thereof, said Shin Ho, operations manager of the family-run Ho Farms. The family grows a variety of colored carrots on its Oahu acreage.
Tomatoes: Ho says there are several varieties of purple tomatoes, some so dark they are almost black. These sweet cherry tomatoes are widely available at supermarkets in “clamshells” as part of a Ho Farms medley of small, colorful tomatoes.
Poi: The Hawaii staple made from taro has been described as a superfood, devoid of fat, sodium and gluten but high in fiber. Taro itself can be cooked any number of ways, including grated and seasoned to make hash browns, boiled and cubed for holiday stuffing, or as a more nutritious substitute for white potatoes. Taro breads and pancakes are already popular, and flour made from taro is gaining popularity as a gluten-free option for baked goods.
