Today's after-hours headlines include food and beverage giant Kraft Heinz (KHC 0.43%) and healthcare diagnostics and research company Natera (NTRA 0.39%).

  1. A potential sale of one of Kraft Heinz's dairy product brands has investors optimistic about management's plans to reinvigorate its business.
  2. Natera's growth in testing drove stronger-than-expected fourth-quarter revenue.

Here's a closer look at these stories -- and why their stocks are moving higher.

A chart showing a stock price moving higher

Image source: Getty Images.

Kraft Heinz

Food and beverage manufacturer Kraft Heinz has had a rough run recently. Last month, shares were pummeled following the company's earnings report. The quarterly update featured worse-than-expected revenue and earnings per share, an announcement of a reduced dividend, and a $15.4 billion writedown on two of its brands: Kraft and Oscar Mayer. 

But the stock is getting a break in after-hours trading on Tuesday, following a report that the company is thinking about selling its Breakstone's business, which sells dairy products like butter and sour cream. Sources "familiar with the situation" told CNBC that the business could be valued at $400 million in a sale. "It could appeal to dairy companies like Dean Foods (DF), Saputo, or national milk cooperative Dairy Farmers of America, one of the people said," wrote CNBC's Lauren Hirsch.

Importantly, CNBC reports that the Kraft's consideration to sell its Breakstone business is "part of a broader review of the company's dairy business, which also includes its natural cheese business, the people said."

Selling some of its brands could help the company pay down some of its debt. Long-term debt has notably risen from $28.3 billion at the end of 2017 to $30.9 billion at the end of 2018. This would add to the company's reinvigorated effort to strengthen its balance sheet, which started with the company's recent dividend cut. 

Kraft Heinz stock is up 0.6% in after-hours trading as of 7:30 p.m. EDT.

Natera

Natera, a company that provides preconception and prenatal genetic testing services, saw shares jump in after-hours trading on Tuesday.

Optimism mounted following the company's strong fourth-quarter results. Revenue for the quarter jumped 29% year over year to $67 million as the company processed 174,200 tests. Overall tests increased 26% year over year, and tests processed through the company's Constellation software platform increased 28% year over year to 10,400.

Natera's fourth-quarter revenue easily beat analysts' consensus estimate for $62.9 million. 

Importantly, Natera's loss from operations narrowed from a loss of $46.6 million in the fourth quarter of 2017 to a loss of $29.7 million in the fourth quarter of 2018.

The stock was up more than 7% in after-hours trading on Tuesday as of 7:30 p.m. EDT.