What kind of food waste is there?

Food waste, commonly known as slop, is domestic waste formed by residents in the process of daily consumption. It is highly susceptible to decay, emits stench, and spreads bacteria and viruses. The main components of food waste include rice and flour food residues, vegetables, animal and vegetable oils, meat and bones, etc. In terms of chemical composition, they include starch, cellulose, protein, lipids and inorganic salts.

1. Process flow

2. Technical indicators

3. Process characteristics

Introduction

Food waste Its main characteristics are that it is rich in organic matter, has high moisture content, and is perishable. Its properties and smell will have a negative impact on environmental sanitation and it is easy to breed pathogenic microorganisms. , mycotoxins and other harmful substances.

What was a delicacy one minute, becomes trash the next. Due to food culture and dining habits, kitchen waste has become a unique phenomenon in China. China's dining tables are incredibly wasteful, producing huge amounts of food waste every day. Figures from the Beijing Municipal Development and Reform Commission show that Beijing generates 1,200 tons of food waste every day. Statistics from the Institute of Solid Waste Pollution Control and Resource Recycling of the Department of Environment at Tsinghua University show that Chinese cities generate no less than 60 million tons of food waste every year.

Experts believe that nutrient-rich food waste is a valuable renewable resource. However, due to lack of attention and improper disposal methods, it has become a potential source of danger affecting food safety and ecological safety. Although improper disposal can have serious consequences, food waste is not without its uses. He Bingguang, deputy director of the Environmental Resources Department of the National Development and Reform Commission, pointed out that food waste has the dual characteristics of waste and resources, and can be said to be a typical "misplaced resource." [1]

Classification

According to different sources, food waste is mainly divided into catering waste and kitchen waste. The former is generated from leftovers from catering industries such as restaurants and canteens, and has the characteristics of large volume, multiple sources, and wide distribution. The latter mainly refers to scraps discarded by residents in their daily cooking, and the amount is not as huge as catering waste.

Hazards

For a long time, China did not have special management regulations on food waste. Some food waste is fed to pigs without treatment, or is recycled and refined by unscrupulous traders to refine waste oil (gutter oil), or is landfilled with ordinary household waste.

Food waste is perishable

Using untreated food waste to feed pigs can easily lead to the spread of diseases. Nie Yongfeng, director of the Solid Waste Pollution Control and Resource Research Institute of the Department of Environment at Tsinghua University, pointed out that food waste generated by the catering industry may contain a variety of pathogens. If livestock and poultry are raised directly without treatment, toxins and harmful substances will accumulate in the livestock and poultry bodies. It brings harm to human health and causes cross-infection between humans and animals. Therefore, this form of food chain hides a huge risk of pathogen transfer and spread. The United States, Canada, the European Union and many other countries have enacted laws prohibiting the direct feeding of untreated food waste to pigs.

Relevant experts pointed out that "gutter oil" contains toxic substances such as aflatoxin and benzene. If it is returned to people's dining tables through illegal channels and eaten by people, it will cause the occurrence of chronic diseases and even cause cancer, which is harmful to people. causing great harm to your physical health.

Researcher Zhang Yuhua from the Institute of Energy and Environmental Protection of the Planning and Design Institute of the Ministry of Agriculture pointed out that because food waste is highly perishable and deteriorates, it will produce unacceptable unpleasant feelings, such as pungent odors. The food waste generated by the catering industry contains a large amount of leftover soup and sour water, which is easy to leak during collection and transportation, affecting the urban environment. Food waste is directly disposed of in landfills, which will cause serious pollution of groundwater. [1]

Resources

According to calculations by relevant experts from the Ministry of Agriculture, food waste contains a large amount of nutrients, the main components of which are oils and proteins.

Food waste

It can replace corn, fish meal, soybean meal, etc. and be processed into high-energy protein and high-quality feed. It is also a suitable raw material for making biodiesel.

Experts explain that based on dry matter content, 50 million tons of food waste is equivalent to 5 million tons of high-quality feed, and the energy contained in it is equivalent to the energy output of 10 million acres of cultivated land every year. The protein is equivalent to the protein output of 20 million acres of soybeans every year. In other words, if all the food waste produced in our country in a year is utilized, it will be equivalent to saving 10 million acres of cultivated land.

He Bingguang pointed out that in the face of China’s shortage of cultivated land and food shortage, and the need to import large amounts of grain and feed every year, rational use of food waste is an effective way to increase resource utilization and solve my country’s food problem to a certain extent. . Moreover, this kind of utilization is in line with the characteristics of reduction, reuse and resource utilization, and is a vivid case of developing circular economy. [1]