You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "what is the most expensive brand of caviar?" whose answer is Beluga caviar.
Each document should contain about 30 words, and these documents should contain useful information.

Query: most expensive caviar brand
Useful Output:

Doc 1: Strottarga Bianco is the most expensive caviar at $113,600 per kg, but it's dehydrated and uses gold flakes. Other top choices include Kaluga
Doc 2: Considering the varieties and their prices, Almas Caviar, sourced from the albino Beluga sturgeon, stands out as the most expensive. Its unique
Doc 3: “Beluga caviar was always considered the best because of its rarity and size, followed by osetra and sevruga,” Panchernikov says. “In addition,
Doc 4: Albino Almas Caviar is the second most expensive caviar in the world, with a price tag of around $35,000 per kilo. This rare delicacy is sourced
Doc 5: There are four different types of caviar – Sterlet, Sevruga, Ossetra and Beluga. The most expensive and rarest of the lot come from the beluga sturgeons