Kamara was playing just his third match since returning from eight months out with a serious knee injury but stood out on a night of few chances as Villa kept their fourth clean sheet in five European matches.
The 25-year-old France international was a regular starter for Emery’s men last season before undergoing surgery on damaged knee ligaments in February.
Emery said: "He’s very important. He has come back. He goes as a six number. He’s giving us a lot of balance, he progressed a lot last year before his injury, playing and with confidence in the build-up.
“He is helping us in this direction. He has a big potential to continue exploiting."
Young defender Sil Swinkels has been rewarded with another new contract just six months after signing his most recent deal.
The 20-year-old Dutch defender has been around the first-team set-up this season and made his senior debut in September’s 2-1 Carabao Cup win at Wycombe.
We are delighted to see Sil sign his new contract,” said Villa academy boss Mark Harrison.
“This is a great reflection of not only his development over the last six months but also the consistent high standards he sets himself.
“Sil is a very good role model for our younger Academy players and we were all delighted to see him make his first-team debut. We look forward to seeing how he continues to develop.”