The new boxes hitting shelves this week list the spongy yellow cakes as having 270 calories and a weight of 77 grams for two cakes, or 135 calories and 38.5 grams for one cake.
Right before it went out of business, the predecessor company had told The Associated Press that Twinkies were 150 calories per cake. Photos of past boxes online also indicate the weight to have been 42.5 grams per cake.
A spokeswoman for Hostess, Hannah Arnold, said in an email Monday that the size change was made in "mid-2012" by the predecessor company. That would mean it happened in the months leading up to its bankruptcy, as the company was trying to keep its head above water financially.
Arnold has also said that the longer shelf life of Twinkies reported by The Associated Press earlier this month was made by the predecessor company right before it went bankrupt. The 45-day shelf life, up from 26 days, was a separate change and hit shelves Nov. 1, she said.
For retailers who request it, the company also said it's freezing Twinkies so stores can stamp their own expiration dates on them.
Hostess has said that Twinkies will remain the same price, at $3.99 for a box of 10. Retailers may charge different prices, however.
Twinkies and other snack cakes were purchased by private equity firms Apollo Global Management and Metropoulos & Co. after Hostess Brands said it was closing down in November.
The predecessor company had failed to reach a contract agreement with The Bakery, Confectionary, Tobacco Workers and Grain Millers International Union, its second largest union, which noted that its members had already taken pay cuts to keep Hostess afloat.
The new owners, which are known for fixing up struggling brands, are not using unionized workers. That means their labor costs are lower than they were for the previous owners.
The bakers union has encouraged the new owners to change their approach and work with its members. It notes that the experience of its members offers "the best chance for long-term success in consistently putting out a quality product."