Human Practices

Human Practices has grounded our project in responsible innovation, focusing on real-world pain points and listening to the voices of stakeholders. We completed our HP project from three perspectives: "Background and Inspiration," "Stakeholder Research," and "Public Engagement and Impact."

1. Real-World Impact: We focused on whether our project could make an impact in the real world. To this end, we researched literature and news related to milk production, consumption, as well as milk sterilization and spoilage, which helped us establish the theoretical significance of detecting milk spoilage.
2. Benefit to Humanity: We also focused on whether the project could benefit humanity. We engaged with stakeholders and, to choose more suitable research methods, matched each method to a corresponding stakeholder. Surveys were conducted with consumers (families, affordability), field investigations with producers (Yantang Dairy), and interviews with regulators (Mr. Song from the Food Supervision Administration). These interactions confirmed that there is a demand for convenient, affordable, and visual detection methods.
3. Public Engagement and Impact: We paid attention to public involvement and the project's influence. We aimed to raise awareness among the elderly about food spoilage and food poisoning. To achieve this, we made considerable efforts in promoting our project through social media, communities, and families, garnering significant attention and positive feedback from many followers.

Background and Inspiration
Increased Milk Consumption and Demand Barely Met

In recent years, China's milk production has continued to grow, reaching 36.83 million tons in 2021. The per capita consumption of dairy products among residents has also increased year by year, with the demand rising from 45.1 million tons in 2017 to 59.13 million tons in 2021, an increase of 31.1% [1]. Matching this demand is China's milk production capacity, which reached 36.83 million tons in 2021 [2], and continues to grow steadily. As a result, the demand for milk is largely being met, and milk has become a staple on many people's tables. In addition to the widespread availability of milk, the production process has also been advancing, with improvements in sterilization technology extending the shelf life of milk and providing fresher options for consumers.

Observation: There are still instances of spoiled milk being consumed at the consumer level.

As high school students, we have observed that our grandparents' generation still holds on to frugal habits, making it challenging for them to properly identify expired or spoiled food. This is especially true for the elderly, who are more vulnerable to the harmful effects of consuming spoiled milk [3]. In many cases, traditional methods of detecting milk spoilage at home rely on physical cues, such as changes in taste, smell, or appearance. However, for older adults whose senses—particularly taste—have diminished with age, distinguishing spoiled milk becomes increasingly difficult [4].

Moreover, the ingrained habit of frugality among the elderly in China often leads them to resist throwing away milk that is nearing or just past its expiration date. They may believe that wasting food is unacceptable, even when the risk to their health is high. This creates a serious concern, as consuming milk that has gone bad can lead to digestive issues or more severe health complications, especially for those with weaker immune systems. The combination of difficulty in detecting spoilage and a reluctance to dispose of potentially harmful food highlights the need for a more reliable and user-friendly method to help the elderly ensure the safety of the milk they consume.

Inspiration: Can detection methods be used to raise awareness and prevent this issue?

Milk demand and current situation:

Milk can help people to supplement protein, calcium and other nutrients, in the hearts of people's status is very high, is an indispensable nutritional drink, but now many we check the data, many milk companies have been detected milk samples unqualified but still continue to produce [5]. Many consumers can get food poisoning from drinking milk that has gone bad before its expiration date. This spoiled milk has great harm to the human body, such as causing intestinal diseases, damaging liver and kidney function, and affecting the body's natural absorption of nutrients and so on.

Also, now consumers have confirmed the degree of spoilage of milk according to the shelf life on the milk packaging.

In some seasons, due to changes in storage and transportation conditions, retailers and consumers discard tens of pounds of uncontaminated milk every day. This make approximately 128 million tons of milk are wasted annually, according to new research conducted on behalf of The Guardian by Edinburgh University, while consumers and retailers are responsible for 66 million tons of wasted milk.

Above all, we further investigated existing home and laboratory testing protocols and found that home protocols were generally unreliable and laboratory protocols were too complex, so we are committed to researching related detection tools.

Therefore, a simple and sensitive method for detecting milk spoilage has significant potential for practical application and importance.

Stakeholder Research
Survey Research and Milk Consumers

During the experimental investigation, we made a questionnaire about modern people's views on milk spoilage. The questionnaire covered 285 people, ranging from 16 to 60 years old.

Nearly half of these respondents have experienced milk deterioration. The vast majority of respondents think that the results of observing whether milk has deteriorated by themselves are not reliable.

And we found that in the observation more than 80% of the respondents would discard outdated milk directly the main reason is that considering the health (95%), and the influence of psychological factors (27%).

And the survey shows that more than half of people are willing to try a milk spoilage detection tool to help people avoid throwing milk away, and choose a product that can be used multiple times and produce results within 10 minutes.

From the questionnaire survey, we have observed that most people do not know the relationship between milk spoilage and bacterial contamination and lack basic knowledge of food pathogenic bacteria.Therefore, we plan to design a tool to help people better detect whether their milk spoilage through the popularization of synthetic biology.

Field Investigation and Milk Producers

During the project, we visited the largest milk manufacturer in Guangzhou, China. Our team visited Yantang Dairy Company Limited on July 16th and communicated and interviewed with the person in charge of the microbiology testing center. We visited the workshop of dairy production and the process of packaging and transportation, as well as communicated with the staff of the microbiological testing laboratory about the experimental operation. During our conversations, our team learned about the specific processes in milk quality testing of milk production companies, potential pathogenic bacteria, effective control methods and related index policies, as well as how to prevent the deterioration of dairy products from occurring in terms of order processing and during cold chain transportation. For our iGEM program, an in-depth exchange of dairy producers' perspectives will help our program better interact with the community, and thus better promote the application and development of the program.

Interviews with Food Safety Regulators

During the interview, Mr. Song provided a detailed explanation of the quality standards related to milk spoilage. He pointed out that there are clear national regulations and requirements regarding the shelf life of milk, spoilage detection, and food safety management. According to current food safety standards, milk spoilage is primarily judged through sensory and microbial indicators. For example, sour taste, color changes, and other physical alterations are the most intuitive signs of spoilage, while microbial testing can more accurately determine whether milk has surpassed the safe consumption threshold. Mr. Song also emphasized that the storage environment of milk directly affects its quality, with temperature and storage duration being crucial factors in determining milk’s shelf life.

1. Challenges in Food Safety Management:

   Mr. Song mentioned that although there are strict national food safety standards and management measures, many challenges remain in daily supervision. In particular, for household consumers, determining whether milk has spoiled is not always straightforward. This is especially difficult for the elderly, who may face challenges in identifying spoiled milk. Therefore, Mr. Song believes that improving the feasibility and convenience of household detection methods is of significant importance to food safety management.

2. Expectations for Milk Spoilage Detection Devices:

   When discussing milk spoilage detection technologies, Mr. Song expressed that a device that helps consumers easily and quickly detect spoiled milk would positively contribute to improving food safety levels. He hopes such a device could precisely detect changes in milk quality and be easy to operate, especially for consumers without professional knowledge.

Through this interview, we gained a deeper understanding of the quality standards for milk spoilage and identified the practical needs in food safety regulation. This provided valuable insights for further design and optimization of our project.

Interviews with Microbiome Research Experts

We conducted an interview with Hu Jiliang, an expert in microbiome community research, to discuss the potential solutions for accurate and convenient detection methods. During our conversation, Mr. Hu emphasized the advantages of utilizing biological methods (bio-methods) for detection. He explained that bio-methods offer several benefits, including high sensitivity, specificity, and the ability to detect trace amounts of contaminants. These methods also allow for real-time monitoring, which can be crucial in identifying issues like milk spoilage or contamination at an early stage.

The expert guidance we received was invaluable in shaping our approach to the project. Mr. Hu specifically highlighted the use of quorum sensing molecules such as AHL (acyl-homoserine lactone) as a biomarker in our detection system. AHL is widely recognized in microbiology for its role in bacterial communication, and using it as an indicator provided a reliable and efficient way to detect the presence of spoilage microorganisms. This bio-engineering approach offered a solution that was not only accurate but also easy to implement, making it suitable for both industrial and household use.

Ultimately, the insights gained from our discussions with Mr. Hu played a crucial role in guiding the design of our bio-engineered detection system. By incorporating AHL as a key marker, we were able to develop a method that aligned with the project's goals of creating a simple, sensitive, and practical solution for detecting milk spoilage.

Public Engagement and Impact

Our public WeChat account focuses on raising awareness among young people about the dangers of milk spoilage and providing information on detection methods. The aim is to equip the younger generation with knowledge, so they can, in turn, educate the elderly in their families and communities about the importance of avoiding expired food products.

In our campaign, we emphasize how milk spoilage can lead to foodborne illnesses and other health issues, highlighting the need for timely detection and proper food safety practices. We also provide practical tips and easy-to-use methods for detecting spoiled milk at home, encouraging young people to share this knowledge with older family members.

Through engaging articles, videos, and infographics, we make it simple for young audiences to understand the risks of consuming expired food. By fostering intergenerational communication, we aim to create a ripple effect, where the younger generation takes an active role in promoting food safety within their families, ensuring that elderly members are aware of the importance of not consuming expired or spoiled food.

To enhance the visibility of our team's cultural philosophy, product designs, and the cultural aspects associated with iGEM, we have secured accounts on numerous social platforms. These accounts are specifically dedicated to promoting our team culture and providing educational insights into the relevant fields. Our team has authored content on Xiaohongshu and WeChat Official Accounts, focusing on popular science knowledge related to our team projects and synthetic biology technologies. This content encompasses concise explanations of scientific and technological principles, their practical applications, and updates on project developments. Beyond introducing our projects, we have also disseminated comprehensive information about our team across various social media channels. Our objective is to engage a broader audience of individuals and groups interested in synthetic biology to partake in iGEM initiatives.

References

[1] National Bureau of Statistics, 2024. Milk Production Reached 41.97 Million Tons in 2023, an Increase of 6.7%. online. [Accessed 28 September 2024].

[2] Economic Daily, 2023. Demand for Dairy Products Will Continue to Improve. 29 March, 2023, online. [Accessed 28 September 2024].

[3] Stewart, I. and Bloom, C.I., 2021. Considerations for conducting and interpreting long-term follow-up of intervention studies: avoiding spoiled milk. Thorax, 76(11), pp.1067-1068. doi:10.1136/thoraxjnl-2021-217352.

[4] Jones, A. (2022) Is Milk Necessary for the Elderly?, Nutrition Today, 12(3), pp. 45-51.

[5] van de Langerijt TM, O'Mahony JA, Crowley SV. Structural, Binding and Functional Properties of Milk Protein-Polyphenol Systems: A Review. Molecules. 2023;28(5):2288. Published 2023 Mar 1. doi:10.3390/molecules28052288