"Some of the predictions being made about complete blanket stoppages occurring at China's border have not materialised," he told the ABC on Monday.
"There remain points of concern, particularly in relation to the length of time for testing regimes for certain goods, because of the time-sensitive nature of that product, it needs to be sped up."
Senator Birmingham said while the government had concerns about the time taken for live lobsters to clear customs, there were some positive signs in relation to Australian wine.
"We continue, as I say, to watch very closely against the type of rumours that have circulated of blanket bans being put in place," he said.
"Chinese authorities, publicly and privately, have denied that sort of application of a blanket ban, and we would hope that they are true to their word in that regard."
Some business bodies, including the Australian Industry Group, have called on the minister to take China to the WTO.
"We've reserved our right there, particularly in relation to the instance of barley," Senator Birmingham said.
"If we have other concerns along the journey which are appropriate to raise with the WTO, we will do so."
Labor frontbencher Penny Wong said the government needed to advocate for Australian exporters.
"Whenever any country unreasonably blocks our exports, we do have to act, whether that's through the WTO or bilaterally or more broadly," she told the ABC.
"We're deeply concerned about the consequences for our exporters and the consequences for Australia's economy about the sorts of trade problems we are seeing with China."
Senator Wong said it was not enough for the government to simply tell exporters to find another market.
"We can't just leave our exporters to go it alone, and the government really needs to ensure that it advocates and supports our export sectors."