https://online2.tingclass.net/lesson/shi0529/10000/10183/802.mp3
https://image.tingclass.net/statics/js/2012
The Results? Without question, double dipping significantly contaminated the dip with oral bacteria. After three dips of an unbitten chip or cracker there were fewer than 800 bacteria in the dip. But after three dips by a pre bitten chip, the bacterial levels in the dip shot up to 500,000 per cup! Several factors contributed to just how much bacteria ended up in the dip. Higher acid dips inhibited bacteria initially, but after sitting for two hours the acidic dip was just as high in bacteria as the more neutral dips were. Dip viscosity also influenced bacteria transfer. Thicker, stickier dips meant that more of the dip that touched the bitten end of the chip stayed stuck to the chip, rather than remaining in the bowl. The moral of the story? Resist the urge. Don’t be a double dipper!