The Big Bang Theory (2007– )
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The Fermentation Bifurcation 

Sheldon and Bernadette spend the evening together while the rest of the gang go to a wine tasting party, but things get uncomfortable for Raj when Penny's ex-boyfriend Zack shows up and takes an interest in Claire.


(as Nikki Lorre)


(created by), (created by) | 6 more credits »

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Episode complete credited cast:


Penny has received tickets to a wine tasting, and has invited all her friends to go with her. Everyone accepts except Sheldon, who has no interest, and Bernadette, who can't drink since she's pregnant. So Sheldon suggests that when everyone else is at the wine tasting, he and Bernadette spend time together doing things for that he normally likes to do and that Bernadette is reduced to now only being able to do since she's pregnant. Bernadette reluctantly accepts Sheldon's invitation. She ends up being surprised by their time together. At the wine tasting, the gang runs into Zack, Penny's old boyfriend who she hasn't seen since before she and Leonard got married. Zack's simplistic way of looking at the world makes for an uncomfortable evening for Leonard, Howard and Raj, the first two who reevaluate working on their prototype for the guidance system, and Raj who is trying to play it overly casual with his date for the evening, Claire, upon her first meeting with his friends. Written by Huggo

Plot Summary | Add Synopsis


Comedy | Romance


TV-PG | See all certifications »




Release Date:

28 April 2016 (USA)  »

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Technical Specs


Sound Mix:


Aspect Ratio:

16:9 HD
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Did You Know?


Amy says she and Howard last spent time together three years ago. This is a reference to the episode where the two were paired together for the scavenger hunt created by Raj; either a reference to the episode itself, or the Neil Diamond concert the two said they should go to. See more »


In this episode, Sheldon states that has avoided raw fish for years. However, in a previous episode (S4 E10: The Alien Parasite Hypothesis) Sheldon is eating sashimi while eating lunch with Amy in her lab. See more »


[first lines]
Penny Hofstadter: Oh, hey, if you guys are free this weekend, I won a night of wine-tasting from work.
Leonard Hofstadter: That sounds fun.
Penny Hofstadter: Mm-hm.
Leonard Hofstadter: How come scientists don't win free stuff like sales people do?
Howard Wolowitz: 'Cause we're not in it for the stuff; we're in it for the groupies.
Sheldon Cooper: Personally, I find the notion of external rewards demeaning; I pursue science for the intrinsic joy of discovery.
Amy Farrah Fowler: But you always say that you want to win a Nobel prize.
Sheldon Cooper: I also say don't contradict me in front of my friends, and that you don't ...
See more »

Crazy Credits


Sometimes I begin writing a vanity card with no idea what I'm writing about. I don't recommend this. What usually happens is I wind up with a collection of sentences that have a vague linear trajectory, but no real purpose. In some ways it's like all the high school and college essay exams where I purposely tried to hide my lack of preparation behind a voluminous cascade of impressive sounding words. My theory was that a thick stack of single-spaced, purple prose would be so off-putting to the teacher, he or she would slap a 'C' on the paper in order to avoid wading through a lot of cursive bull$#!+. Needless to say, the short, succinct style of these vanity cards forestalls that exact approach, but I am hopeful it still has the power to distract. Sonorous fodder like, "vague linear trajectory," "voluminous cascade," "forestall," and "sonorous fodder" are all used to just that end. Which raises the question: Why? What compels me to obfuscate? Sadly, I have no good answer. I do have a bad one. I take a childish delight in wasting your time. I know that's setting the bar pretty low, but keep in mind, at an early age I was happy to get a 'C'. See more »


References Star Wars: Episode IV - A New Hope (1977) See more »


History of Everything (Instrumental version)
Written by Barenaked Ladies
Performed by Barenaked Ladies
[Instrumental version of series theme song played over the closing credits]
See more »

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User Reviews

Great episode!
28 July 2016 | by See all my reviews

Loved seeing Zach again and with a fun role in this episode! It added so much to the interaction between characters. Great scenes with Sheldon and Bernadette and of course their interaction is entertaining! Always good to see old friends return to the show. We know their personalities, but the writers create wonderful dialogue and relationships. Zach's lines were super funny. Thanks for this episode! Interested to see how Raj's relationship with Claire proceeds after the challenges established. Not sure why we lost Emily from the cast? We enjoyed seeing the partners interact with others partners from time to time and this episode provided that. Almost as good as Amy & Howard singing Neil Diamond! Zach added some zest to their discussion and their moral dilemmas so he was a welcome visitor. What a pleasant surprise to see him at the wine tasting! Curious how Bernadette will deal with the pregnancy belly strap on next season!

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