The first and perhaps most important tip for enjoying instant mashed potatoes at Thanksgiving is to never, under any circumstance, read the ingredient list. Any fantasy you might have about whipping up buttery, all-natural potatoes from a box of dehydrated flakes could be instantly dispelled by a convenience-foods industry that tosses in additives to, among other things, improve texture, preserve color or prevent caking.

“Hey, Dad, can you pass the mashed potatoes with mono- and diglycerides for better mouth feel?”

In an era of locavorism and sustainability, instant mashed potatoes can seem like a regression to the 20th century, when home cooks, looking for more leisure time, handed over their meals to big business, a trend that would ultimately inspire the food revolution backlash. But if U.S. food manufacturers understand anything, it’s that they must adapt fast to the ever-changing concerns of the American eater. Instant potato producers are no different.

Among the boxes the Food section found for our instant mashed potato taste test were ones produced by 365 Everyday Value (the Whole Foods line), Trader Joe’s and Edward & Sons, the natural foods company. Their contents sometimes inspired far less trepidation than those boxes whose ingredients looked as if they came from a petri dish, not a potato field.

But these gourmet-minded instant spuds — the 365 box, for example, boasts just one ingredient: dehydrated potato — also raised questions. Would dehydrated potato flakes, without the help of chemical additives, reconstitute into something even remotely resembling fluffy mashed potatoes built from boiled spuds?

For the blind tasting, the Food staff located 16 boxes for potential inclusion. After reviewing the ingredients for each, I whittled the challengers down to eight, with four others placed on a list of optional boxes to test. I booted boxes that featured the exact same ingredients as ostensible competitors and deemed others optional if they were just variations on a manufacturer’s main instant potato line. In the end, we tested 10 boxes, dropping those by Giant, Wegmans, Safeway and Gold Emblem for mirroring ingredients found in Betty Crocker Potato Buds or some other brand.

The results were wild. The five judges could not find agreement on any one box, based on a scoring system of 1 to 5, with the latter number presenting the pinnacle of dehydrated potato goodness. The winner, Honest Earth All Natural Creamy Mash, averaged 3.2 points in overall scoring. Three judges thought it merited a 4; two others couldn’t rate it above 2. (Worth nothing: The product is exclusive to Costco and a pair of online sites, and it must be purchased in a quantity that would make even the Thanksgiving table groan under its weight.)

“I like a stiff mashed potato, and this fits the bill,” wrote judge Mike Greenberg, an advertising copy writer for The Post, who gave Honest Earth a 4 rating overall.

Compare that with Food and Travel Editor Joe Yonan, who lowered the boom on Honest Earth with a 2 score. “Tastes like baby food!” he spat.

The second-place boxes — Idahoan Baby Reds Flavored Mashed Potatoes and Idahoan Original Mashed Potatoes tied with an overall score of 3 — generated equally diverse opinions. “Way too overprocessed, but the flavor isn’t bad,” wrote Jane Touzalin, a Post multiplatform editor, about the Idahoan Original Mashed Potatoes. This was Touzalin’s way of saying she liked the product; she gave it an overall rating of 4.

“Appearance killed it,” noted Mary Pat Flaherty, a Post investigative reporter, in bestowing a lowly 2 on the same box.

Inconsistencies and incongruities were the norm. If our testers are representative of modern eaters — people looking for natural, more-healthful products — then they should pat themselves on the back for their No. 1 pick. Honest Earth’s ingredient list is a model of simplicity: “potatoes (including peel), butter and sea salt.”

Conversely, the ingredient list for the Idahoan Baby Reds Flavored Mashed Potatoes looks like a horror novel you might read to Michael Pollan before bed. Among the many chemical additives: maltodextrin (a powder often used to add texture), silicon dioxide (an anti-caking agent) and sodium bisulfite (to maintain freshness).

Did I mention that Honest Earth is owned by Idahoan?

And what about that 365 Everyday Value product from Whole Foods that has just one single ingredient? It placed dead last. The judges may have a mind for natural foods, but they have a palate for chemicals, too.

Above are the 10 products and how they fared, from highest to lowest score. For the sake of comparison, a basic mashed potato recipe would cost about $5.35 to prepare (based on prices from Peapod), which breaks down to about 67 cents per serving.

See the full results

The 2013 Holiday Guide