Bacteria dropped. As a follow up, the experiment was

Bacteria surround the everyday environment and are mostly safe microorganisms. When it comes to food, some microbes can be spread in many different ways in which can cause and spread illnesses. The experiment conducted was testing the 5 second rule to obtain information about the quantity, type, and interactions microbes on a baby carrot. The experiment itself was carried out by dropping baby carrots on the floor, one for 5 seconds, another for 5 minutes, and a control which was not dropped. As a follow up, the experiment was redone but the carrots were washed for a minute with tap water prior to being dropped. Then the carrots were diluted and plated to grow colonies which then were DNA sequenced to find the individual species on the carrot. Results showed that microbes still attached to the carrot, regardless of the 5 second rule, and there was minimal difference of bacterial amounts between 5 seconds and 5 minutes. For the follow up experiment, the data showed that washing reduced the bacterial counts on the carrot. Many species of bacteria were found, some of which are pathogenic. To conclude, the 5 second rule is not an accurate representation of safety precautions and washing can help decrease some bacteria.Microbes are on everything and are everywhere, but we rarely think about the ones on our foods. Mainly when people think about microbes/bacteria on foods, bad bacteria like mold and food poisoning are thought of. However, most microbes aren’t as bad as some may think. Most of these microbes are a normal part of life and some are even beneficial to the body. Some types of food including chocolate, yogurt, bread,cheese are made specifically from using bacteria through the process of fermentation. All types of food have different amounts and types of the microbes they carry. Factors like production, packaging, and storage can attribute to microbes and their conditions. Though most are harmless, some types of bacteria are pathogenic and can cause illness or disease. If food is not properly handled, packaged, or stored, dangerous bacteria can produce toxins that could be transferred onto a product and then possibly to a human. Bacteria can be easily spread if food is not sanitized, washed, cooked, pasteurized, and etc. Some well known illnesses from consuming infected foods are food poisoning, salmonella, E.coli, and norovirus. These illnesses can affect everyone and may even lead to hospitalization. Symptoms vary but the most common include; vomiting, fever, chills, and diarrhea. Some of these illnesses can cause dehydration and may even lead to long term health problems. These dangerous bacteria usually cannot be seen and affect people in different ways. Bacterial cells have consistently been to blame for compromising the safety and quality of all types of foods. When these harmful cells are not removed, the microbes can adhere and reproduce which can cause biofilms. Strategies can be made to prevent the attachment of bacteria by knowledge of the relation between surface conditions and adhesion (Bower, Mcguire, Daeschel). Other cells can cause spores and release dangerous toxins that can affect/target a variety of cells. A study found that with increases in fresh/organic ready to eat vegetables and mild processing/storage techniques, new potential indigenous and pathogenic microorganisms have surfaced. Researchers explained that with these new potentially harmful bacteria, they may have different ecosystems which can impact their survival and growth(Francis,Thomas,O’beirne). When properly grown and stored, carrots as well as other foods are generally considered safe to eat. Problems like transporting and washing the products can have major effects on the bacteria on it. Some of the most common illnesses from carrots are due to improper storage techniques (for example refrigeration) and packaging (considering bag, containers, liquids). These factors can impact shelf life as well as quality issues, which may not be seen to a consumer. Commonly, carrots have labels that say “ready to eat” or “pre-washed”, these labels may play a big role in why more people are becoming ill due to these food borne microbes because of the false sense of safety. Since carrots are a root vegetable they can get exposed to microbes in a number of ways including land use history, fertilizer use, irrigation, field sanitation, field containers, and pesticide usage, harvesting, and handling. Carrots, among other vegetables, are affected by fungi, bacteria, and nematodes from field to storage. The two most common bacteria found in soil are Bacillus cereus and Listeria monocytogenes. Some carrot bacteria, like Xanthomonas campestris pv. carotae, can be spread through the soil by rainfall or irrigations systems. Some of the effects these disease have on the carrot include rotting, cavity spots, discoloration, and pitting. It was observed that carrots may be more vulnerable to disease because of the fact that it’s a root vegetable. Root vegetables can have more environmental risks because they are mostly submerged in soil. Any produce that is grown on a farm with animals, also is shown to have higher bacteria counts. Wider distributions and bigger demands is known to increase pathogenic microbes as well. An article explained that the bigger demands of these vegetables, causes these products to be imported from other countries, which may not have as good of sanitary conditions as others (Kamps,1).The microbes found as a group were Flavobacterium plurextorum, a fungus species, Janthinobacterium, Candidatus Thiopilula aggregata, Rahnella aquatilis, Pantoea agglomerans, Pseudomonas mandelii, Pseudomonas Koreensis, as well as other Pseudomonas species that were unidentifiable. 8 out the 14 samples we were able to sequence, were Pseudomonas. The microbes I found in the colonies that were DNA sequenced from my samples were Pseudomonas Fluorescens and Pseudomonas Koreensis. Both of these bacteria are rod shaped as found with gram staining. Pseudomonas Fluorescens is a common gram negative bacteria that is found in soil and water. The colony of this microbe was slightly big and an off white color. Pseudomonas Koreensis is a fairly uncommon gram negative bacteria that was originally found in korean soil. The colony of this microbe was on the smaller side and was a light yellow color. These species I found were taken from the same plate, and were the only colonies on it. Researchers also have debunked this 5 second rule. A study found that when comparing hard food and soft foods for bacteria when left on the floor, ultimately there was substantially less bacteria found on the hard food. From this study these scientists were about to conclude that the type and texture of the foods are the factors in which bacterial transfer is dependent on. Also these researchers showed that bacterial transfer is again dependent on the contact time given with wet and or adhesive foods (Lipschutz,Kagan,Steed).  Similar to our experiment, we also found that time was an effect on bacterial growth. Another study examined how washing lettuce and the methods used by washing affect the microbial count. Researchers used ‘ready to eat’ salad and were washed in a high flow rate, and results showed a decrease in Enterobacteriaceae by nearly 68%. This study concluded that basic household washing of these vegetables best reduces the aerobic count of enterobacteriaceae at 90-97%. They did however claim that the vegetables still had high amounts of bacteria even after that particular microbe was washed away (Uhlig, et al.). This relates to our experiment because though the washed carrots did have reduced amounts of bacteria compared to non-washed, bacteria like Pseudomonas was still present on the carrots.  Pseudomonas mandelii is found in natural spring water, this could have been found due to water on someone’s shoes, or from liquids in the carrots packaging. Pseudomonas Koreensis is related to farming soil in Korea, this is unlikely but could be due to where the carrots were grown, or someone had traveled from Korea. The few that aren’t associated with soil include Pantoea agglomerans and Flavobacterium pluxertorum. Pantoea agglomerans is commonly associated with plants, and is pathogenic. It is possible that someone may have tracked in plant/leaf contamination from outside. Flavobacterium plurextorum is found mainly in fish, 


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