Between the stock market sitting near all-time highs, valuations looking stretched by historic measures, and risks that the Federal Reserve may start tightening monetary policy, you have good reason to worry. If a frothy market and uncertain policy have you concerned, now might be a great time to add some ballast to your portfolio to help you manage the ups and downs that may be headed our way.

The good news is that not every stock has skyrocketed in the recent market run-up. There are still a handful of solid companies whose businesses are simply too boring and predictable to have been worthy of such gains. That boringness during the rally just might end up turning into resiliency during any upcoming frothiness. With that in mind, here are three resilient stocks to help solidify your portfolio.

Peanut butter and jelly sandwich

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No. 1: Comfort food for uncomfortable times

J.M. Smucker (NYSE:SJM) is best known for its namesake jams and jellies, but the company also makes such food giants as Jif peanut butter, Folgers coffee, and pet foods like Meow Mix and Milk Bone. Analysts only expect low single digit growth from the business over the next few years, which is probably why the company trades at just 17 times its trailing earnings.

That relatively reasonable valuation means that the company's dividend offers its shareholders a solid 3.2% yield,  while only consuming around half of its earnings. As befitting a company in a fairly stable business line, JM Smucker increased its dividend by 10% earlier this year, with that increase representing its 20th consecutive year of rising payouts.

In addition, JM Smucker carries a pretty clear balance sheet, with a debt-to-equity ratio below 0.6 and a total debt load below two years' worth of its gross profit. All that may add up to a fairly boring business, but it is also the sign of a company that looks resilient enough to hold up reasonably well in uncertain times.

Rock of Gibraltar

Image source: Getty Images

No. 2: A rock-solid insurance giant

Insurance titan Prudential Financial (NYSE:PRU) cares so much about showcasing its rock-solid financial footing that it uses an actual rock -- the Rock of Gibraltar -- as its logo. That rock-solid position can best be seen in its balance sheet, which sports a debt to equity ratio below 0.6 and over $15 billion in cash and equivalents on hand.

Although analysts are projecting only single-digit growth over the next few years, its market price below 0.7 times its book value and only around 8.5 times its anticipated earnings makes it a reasonable value. That value price means Prudential Financial can offer its shareholders a 4% dividend yield while consuming only around a quarter of its earnings.

As befitting a company that cares deeply for its financial strength, Prudential Financial did reduce its dividend during the financial crisis. Still, what it pays each quarter today is what it paid for a full year before that crisis hit. That showcases just how well patient investors can be rewarded by a rock-solid business over time, even as it navigates some rough waters.

When it comes to resilient businesses, it's hard to beat one that operates the way that Prudential Financial does. No, it's not going to set the world on fire with its growth potential, but it's also well set up to be a potential survivor in the frothy future we may very well have ahead of us.

Pipelines in the setting sun.

Image source: Getty Images

No. 3: An infrastructure titan that has fortified its foundation

Pipeline giant Kinder Morgan (NYSE:KMI) lost a lot of credibility among income-focused investors when it slashed its dividend in late 2015. Yet it did so for good reason -- to protect and shore up its balance sheet. It has done an incredible job of doing that, and it has since been able to begin restoring its payout. 

Kinder Morgan's dividend now sits at a juicy 6.1% yield, and its payout is well covered by its operating cash flows. Those operating cash flows held up even as it reduced its dividend, and that cash played a huge role in the company's ability to shore up its balance sheet over the last several years.

Over 90% of Kinder Morgan's operations are supported by contracts that are either fee based or "take or pay". That means its fortunes are much more tied to the amount of oil and natural gas flowing through its pipelines than the price that energy fetches.

And despite the growth of renewable energy, according to the US Energy Information Administration, oil and natural gas use is expected to continue to increase over the next few decades. That points to continued demand for Kinder Morgan's services. After all, pipelines tend to be both cost effective and among the safest ways to transport such energy. That all adds up to a fairly resilient business that looks likely to be able to continue delivering value even if we face turbulence in the not too distant future.

Solid businesses in different industries for uncertain times

Adding to the potential of your portfolio's overall resiliency, JM Smucker, Prudential Financial, and Kinder Morgan all operate in different industries (food, insurance, and energy, respectively). That makes it more likely that an issue that knocks one of their businesses for a loop could leave the others relatively unscathed.

As a result, they're worth considering as resilient stocks on their own as well as worthy of consideration as a collection as part of a diversified portfolio. In uncertain times like the ones we may be facing, investments such as these just might be able to provide the solid foundation your portfolio needs.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.