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Name: Brett
Status: Student
Age: 13
Location: N/A
Country: N/A
Date: N/A 


Question:
I would like to know how to classify the bacteria found in yogurt. I know most of their names, I just don't know what they are supposed to look like.

Can you Help me?



Replies:
Cultures (not the blended kind). I have my students gram stain a small bit of the yogurt to see that there are actually living bacteria in it. The bacteria we see are Gram positive (purple) and are cocci (round) in chains ( Streptococcus lactis) and bacilli (rods) in chains or singles (Lactobacillus sp.) These are bacteria that use lactose (milk sugar) for their energy source. The acids they produce as end products of their metabolism (waste) curdle the milk protein and also give the sour taste to the yogurt.

vanhoeck



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