The "propaganda" Franzia refers to is a blog by a writer named Chris Knox that showed up on The Huffington Post last week.
"These aren't hand-picked vineyards. ... They are machine harvested," Knox wrote. "Everything, and I do mean everything (including all those unripe grapes, rotten grapes, leaves, stems, birds, rodents, and insects) gets tossed into the crusher and transferred to largest tanks to ferment. So think about all the animal blood and parts that may have made their way into your wine next time you crack open that bottle of Two Buck Chuck!"
Franzia's reply: "He didn't know what he was talking about. He's never been in a vineyard, doesn't understand it."
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Franzia does use mechanized harvesting, as do an increasing number of grape growers. He insists the machines shake loose everything but the grapes, and there are other methods along the way to filter out leaves, twigs and animal residue.
"We're in the grape-picking business," he said. "We're looking for quality wines and quality grapes. We're not looking for animals."
Some animal matter does end up in winemaking, as it does in almost all agricultural products. "If you worry about things like that, you shouldn't eat anything, you shouldn't drink anything," Franzia said. "When the wine's fermenting, they're going to eliminate anything that's possibly there."
So who is Knox and how did his blog end up on The Huffington Post? Here's what CNBC found: The blog was posted on HuffPo through a separate news site called Quora, which has used The Huffington Post to promote its own content. CNBC's efforts to reach Knox were unsuccessful, though it appears he works in some capacity in the wine industry in Santa Ynez, California.
Knox did not respond to our messages. However, on the Facebook page of another Napa winemaker, a man who appears to be Knox said he wrote the Two Buck Chuck post three years ago for Quora.
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"I actually had NO IDEA my words had even been published on Huffington Post," he wrote. "Though I certainly didn't intend to be completely inaccurate, I also never intended it as a fully qualified, well researched piece of accurate journalism. ... Lesson learned that we must all be VERY careful about ANYTHING we publish online."