Team:Hong Kong UCCKE/Human Practices
Human Practice
Questionnaire
After inspired by the food waste disposal situation in the school cafeteria, we conducted a survey which we received responses from 450 individuals with most of the respondents living with 2 or more family members in their household.
Results
The majority of respondents (71.8%) produce food waste each day. Over 75% of those who dispose food waste produce more than one bowl (measure roughly by Chinese rice bowl) of food waste every day. The main types of food thrown away are rice, vegetables, meat and fruit. Over 90% of the respondent say that they dispose their leftovers as garbage while only a small group will recycle the food waste (3.7%) and convert food waste to fertilizer (3.4%). 63% of the respondents will consider buying a food waste conversion machine and will consider the price, the size of the machine, the smell produced from the machine and the decomposition efficiency. Half of the people who will consider buying a machine will want to pay no more than 130 USD and the other half is willing to pay more than 130 USD. Lastly, over 90% of respondents is willing to use detergent made from fermented or decomposed food waste.
Conclusion
The survey results supported our prediction, composting my not be the best solution to domestic food waste. Due to the large number of leftovers in each household and Hong Kong people’s habits of not using the recycling bin frequently, we believe setting up a conversion machine at home is convenient and fit Hong Kong people’s lifestyle. Also, we designed genes to further digest starch and meat is also the two main categories of food that people most often dispose. The conversion machine is hopefully welcomed by consumer, only we have to consider the price and the size of machine in order to successfully introduce the device to common household. Also, the gene which we designed to tackle the smell problem is also responding to the consumer’s concern. Lastly, we believe the direction of turning food waste in to detergent is correct and will most likely be well received.
Interview with Professor Wong
Background:
UCCKE iGem team was honoured to interview Professor Wong, Jonathan Woon Chung,professor and Head of Department of Biology in Hong Kong Baptist University, also a Chief Operating Officer of Hong Kong Organic Resource Centre. We interviewed him on the 1st of February 2019 to know more about the methods of processing food waste.
Food waste problem in Hong Kong:
Professor Wong bring out that people use bacteria in soil to break down food waste which cellulose and other substances are broken down to CO2, fibres are left as they are hard to break down. Eventually, those fibres are stable and can be used for farming. As food waste is left alone for a long period of time before processing, they will undergo anaerobic digestion which will create a very acidic environment, causing initial stock up process difficult such as composting, which the environment will be too acidic and kill the bacteria.
Interview with eco-greenery
Background:
We interviewed one of the Hong Kong local organisations Eco-greenery. Their main campaign is reusing coffee residue for fertilising and odour remover. It also has another campaign on collecting food waste and upcycle it as compost. We interviewed them on the 13th of September to discuss their problems when collecting and processing food waste and some suggestions towards our project.
How their campaign operates:
The main source that they collect food waste from the banquet and buffet. They usually comes with a lot of moisture and the variety of food is very large such as bones or eggshells. They mentioned that because the types of food waste will constantly change, therefore they choose to use it as compost. Thus, there isn't another way for processing food waste. This project doesn’t really make a big profit since lots of money were used for classifying the food waste and transportation, which is why designing a food waste conversion machine for a household can reduce the time and cost that goes to solving the food waste problem.They will give the final composting product to the local farmers without any costs to support their agricultural activities. After categorisation they will process their food waste about 200 kg each time. As they process the food waste, it gives out an unpleasant smell. They told us they will add bokashi which is a mixture of different yeast to resolve it by killing the bad bacteria.
Comment towards our project:
She thinks it is a decent idea as the space in Hong Kong is so small but worries that there may be a hygiene problem. And also the price and design of this machine must be acceptable to be welcomed by the consumers. She thinks positively towards the idea of using rice as detergent but find it difficult to collect white rice(rice without sauce). She stated that the mass of the food waste will not decrease drastically, and solid will still remain. If the process of eco-enzyme is very aggravating, then consumers may rather buy detergent then make their own, considering the affordable price of detergents nowadays. Also the power that is used to operate the conversion machine should also be remained low to ensure the device is environmentally friendly.
Follow up phone interview with eco-greenery:
We phoned the company to ask for more details about the mold problem we discovered on the 21st of October after conducting a set of experiments with bokashi.They stated that the growth of mold in the process means the fermentation process within the food waste is occuring. They suggested no water should be added as respiration will already produce water. If there is an excess amount of water inside the mixture, it will have other side effects, for example encouraging insects growth,leading to worrisome hygiene problems.
Interview with S.1 students
During April to May of 2019, we visited the school S.1 canteen weekly to investigate the food waste problem in school .We found out that the food waste left by the whole form usually takes up one to two whole table, about 20 dishes. The most common types of food waste are vegetables and rice. Some dishes are even thrown without opening the food wrappers. After interviewing with S.1 students, we found out that they are being picky with canteen’s food and sometimes students may buy snacks from tuck shop, which resulted tables of food waste. Students tried to reflect this problem to the school lunch supplier, but since the food portion is fixed, therefore the food waste problem can’t be resolved by reducing the food portion.
Interview with Mrs. Wong
Regarding the issue that mold is breeded during the fermentation of food waste, we asked the school chemistry teacher for opinions. Firstly, she suggested there might be some chances that when we release the air pressure inside the plastic bottles samples weekly, the supply of air allowed harmful bacteria to grow due to high humidity in the air. She suggested the experiment team try to maintain an air-tight condition to prohibit growth of harmful bacteria.
Peninsula Life
Background:
Our whole team joined a workshop about Hong Kong food waste problem in July. Since the centre have demonstrations of food waste composting and sewage handling system, we would like to visit and learn about their operating process ,as well as problems they will face while handling food waste as our reference for our project.
Workshop:
During the discussion with the workers, we are surprised that around 71% of food waste comes from household leftovers, while the remaining 21% are classified as industrial use. And the main problem of Hong Kong landfill is they will be full in the coming few years.
Workers demonstrated using coffee residue as food waste compost, and using earthworms and black soldier fly as organisms breakdown to make fertilisers. These fertilisers are rich in nutrition and has no smell, which a lot of farmers love to use it as organic farming.
Workers point out that since food waste contains over 70% water, so they use this sewage handling system to breakdown different materials in sewage. But first they will heat up the food waste to remove water, and the breakdown process usually takes 24 hours. And the leftover food waste water will use spherical container , it increases the surface area for microorganisms to contact with the contaminant.
They reminded us that in Hong Kong a lot of farmers have been registered as “organic farms” ,they will not accept fertilizers and compost made up by food waste, since it possibly contain GM crops and will affect their brand image. Everyone has dishes to clean so detergent can be used by all the users.Therefore homemade detergent will be more persuasive and pleasant to users.
Inspiration:
After joining the workshop, we found out that maybe we can focus on improving adversities faced by recycling industry which we discovered. And we may also us organisms as to help to breakdown the food waste to speed up the process.We mainly focus on new societal trend and demand of the market.
