A Melbourne wine expert, reviewer and former sommelier has been accused of stealing up to $300,000 worth of wine while working as a buyer for Melbourne wine importer Cellarhand.

Lak Quach allegedly stole and re-sold wine “to more than a dozen of Melbourne's most exclusive restaurants and retailers”, before taking the money he earned to buy collectable bottles for his own private collection, the Age reports.

Cellarhand is investigating the claims. According to the Age, Quach has “made some admissions” to the company’s director Patrick Walsh, who first met the young wine expert at Langtons Restaurant and Wine Bar in 1999.

Broadsheet called Cellarhand for comment. The person who answered the phone said no-one was available to discuss the incident and declined to comment.

Quach was named dux of the 2013 Len Evans Tutorial, a prestigious week-long training and masterclass initiative in which 12 students open and taste “many of the greatest, rarest and oldest wines of the world”, according to the website.

James Halliday, one of the program’s trustees and tutors, is quoted on the website as saying, “Lak demonstrated at every turn an excellent grasp of world wine styles, culminating in picking 4 of the 6 Grand Cru vineyards in Friday’s DRC Masterclass. A very worthy Dux.”

Quach went on to become a contributor for the Halliday Wine Companion, and joined Cellarhand in 2011.

References to Quach have been removed from the Cellarhand website, though his name appears on a number of tweets from the company’s Twitter account, including a since-deleted tweet congratulating Quach on joining Halliday’s Wine Companion, calling him “an invaluable member of the Cellarhand team.”