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The Food and Drug Administration recommends against washing raw chicken due to the risk of transferring dangerous food-borne pathogens through splashed drops of water. Many cooks continue to wash raw chicken despite this warning, however, and there is a lack of scientific research assessing the extent of microbial transmission in splashed droplets. Here, we use large agar plates to confirm that bacteria can be transferred from the surface of raw chicken through splashing. We also identify and create a phylogenetic tree of the bacteria present on the chicken and the bacteria transferred during splashing. While no food-borne pathogens were identified, we note that organisms in the same genera as pathogens were transferred from the chicken surface through these droplets. Additionally, we show that faucet height, flow type, and surface stiffness play a role in splash height and distance. Using high-speed imaging to explore splashing causes, we find that increasing faucet height leads to a flow instability that can increase splashing. Furthermore, splashing from soft materials such as chicken can create a divot in the surface, leading to splashing under flow conditions that would not splash on a curved, hard surface. Thus, we conclude that washing raw chicken does risk pathogen transfer and cross-contamination through droplet ejection, and that changing washing conditions can increase or decrease the risk of splashing.
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This content will become publicly available on June 13, 2026
Light-Induced Polymer Drop Splashing
This study seeks to understand the role of photodegradation of aqueous polymers in drop splashing. Polymer drop impact commonly occurs in various industrial applications such as inkjet printing, spray coating, and agrochemical sprays. In agrochemicals, the various constituent components (e.g., adjuvants) imparts multiple changes to the fluid dynamics and the wetting behaviors of the drops, as well as interacting with the environmental conditions. The environmental conditions (e.g., thermal-degradation, photo-degradation, and oxidation) of the chemicals affect the shelf stability of the intended physicochemical properties of the chemicals, which are added to stabilize drift from the spray nozzles and minimize drop bouncing from leaves. The aging effects of the adjuvants in tandem with the already low pesticide delivery efficiency has an unknown effect on the agrochemical delivery efficiency and the related environmental burden from the increased run off. Herein, we systematically photo-degraded polyethylene oxide (PEO) to probe the drop splashing behavior as a result of the simulated aging conditions. Dye was added to accelerate the degradation of the polymers and caused drops to splash at Weber numbers where the pure PEO case did not, confirming the need to consider environmental factors which contributes to adjuvant aging in agrochemical applications. We have also conducted experiments with various concentrations of PEO to probe the changes in the splash dynamics as well as including surfactants, which played a marginal role in altering the splash dynamics under our parameter space. The significance of the study is that the degradation of the polymers influences the splashing and increases the amount of splashed droplets, indicating the importance of controlling the environmental conditions under which polymer solutions are stored.
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- Award ID(s):
- 2137341
- PAR ID:
- 10611362
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Langmuir
- Volume:
- 41
- Issue:
- 25
- ISSN:
- 0743-7463
- Page Range / eLocation ID:
- 15926-15935
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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