Upscale organic grocer Whole Foods Market easily hurdled analysts' estimates in its second quarter this week, posting a profit of $90 million, or 51 cents a share, on sales of $2.4 billion.

Analysts surveyed by Thomson Reuters pegged the Austin, Texas-based company for a profit of 46 cents a share on sales of $2.37 billion.

As if the upside surprise wasn't enough, Whole Foods raised its full-year earnings target from $1.80 a share to $1.90 a share.

"These are the strongest overall results we have reported in the past five years," CEO John Mackey said in a statement announcing the blow-out quarter. "We are very proud of our balance sheet and that, despite a much tougher year-ago comparison, we are reporting our sixth consecutive quarter of accelerating two-year identical store sales growth."

The company also announced it will be changing its ticker symbol from "WFMI" to "WFM" on the Nasdaq exchange starting May 6.

Speaking of the stock, it roared up $3.44, or 6%, to $63.18 in after-hours trading closing off 3 cents a share in the regular trading session.

Comparable store sales improved 7.8% from the year-ago quarter and the company is on track to add another 61 new stores over the next four years.

Whole Foods' strong quarter and revised guidance would seem to imply the overall economy is starting to crawl -- if not walk -- after a prolonged hibernation considering its extensive lines of natural and organic foods are typically much higher priced than similar non-organic fruits and vegetables sold at traditional supermarkets.

Morningstar currently rates competitor Safeway (NYSE: SWY) one of its best consumer cyclical picks mainly because the stock is so undervalued ($24 a share and price-to-earnings ratio of 15.48)  based on its expected future cash flows and the fact that it recently completed remodels of most of its stores to look and feel more like Whole Foods.

Whole Foods is trading near its 52-week high of $66.87 set in April, more than double what it was trading at in July, and has a P/E of 37. Still, 14 of the 24 analysts tracking the stock rate it a "hold."

Analysts are looking for full-year sales of more than $10.2 billion.