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Confronting food waste: restaurants eliminating food waste

Confronting food waste: restaurants eliminating food waste


In recent decades, food waste has risen as a serious issue around the world. It is roughly calculated that worldwide 1.3 billion tons of food are wasted. In the US, the number is around 56 to 72 million tons. (2)


The US Environmental Protection Agency (EPA) defines food waste as “Uneaten food and food preparation wastes from residences and commercial establishments such as grocery stores, restaurants, and produce stands, institutional cafeterias and kitchens, and industrial sources like employee lunchrooms.” (3)

“Restaurants should be responsible for the majority of food waste outputs”

“Restaurants should be responsible for the majority of food waste outputs”, said Elizabeth Balkan on PBS Newshour (4). In her opinion, leftovers on people's plates and post-consumer waste like bones and species are the main two sources of food waste. During her talk, she mentioned the negative environmental impact on food waste landfill which releases a large amount of methane– another greenhouse gas which is up to 86 times more powerful than carbon dioxide. What is worse, global warming is not only a problem when food waste is sent to landfill. An Australian scientist (5) claims that the leaching and runoff from dumped food waste containing a massive amount of Nitrogen can contaminate rivers and groundwater by the process of eutrophication.

美国环境保护署(EPA)将食物浪费定义为:“未使用食物/食物原料垃圾,源自住宅或商业场所(如杂货店、饭店、食品摊位、食堂或厨房)和工业场所(如员工餐厅)”。“饭店需要为大部分的食物浪费负责”( Elizabeth Balkan 在 PBS Newshour )在讲话中她谈到废弃食物的另一个负面影响——填埋后产生的甲烷。甲烷比同为温室气体的二氧化碳温室效应强86倍。填埋还有另外的负面影响:一位澳国科学家声明,废弃食物中富含的氮将使临近的水体富营养化。

Courtesy of (6) A demonstration of how the decomposition of food waste contaminates both atmospheric and aquatic environments. Note here the product of carbon dioxide and another toxic organic along with inorganic matters are also spilled out, considering various sources of waste besides food waste. 厨余垃圾污染大气和水体的示意图(考虑到被填埋垃圾不止是食物,也有其他有机/非有机污染物质产生)感谢EPA提供

So, how could restaurateurs respond to this crisis? Well, there are three initiatives that can lead to more obvious effects: planning, food bank, and reusing.


Food Waste Reduction Hierarchy. Courtesy of EPA. (7) 减少食物浪费的层次。感谢EPA提供

Planning food waste reduction


The prior approach to reducing food waste is definitely not to create it for the first time (7)(8). But when getting managed, the first step to a successful food waste reduction plan should be to measure the quantity you are wasting, the cost of that waste, and what the sources of the waste are. Usually, this food waste could be avoided by improving product development, storage, shopping/ordering, marketing, labeling, and cooking methods.


The simplest way to measure your food waste could be separating different types of waste:


Trash 1: Preparation waste - the waste generated while prepping food e.g. clamshell and wheat stem.


Trash 2: Spoilage – It can be separated into two scenarios. One is the food nearly closing to the date of expiration while still storing in the fridge or other storage, the other is the food already deteriorated, with plenty of mold and bacteria.


Trash 3: Plate waste - Served food that customers didn’t eat, i.e., leftover.


Courtesy of tenzo. (8) 感谢tenzo提供。

Food Bank


If there is plenty of food stored in the fridge that is approaching the expiry, donating to the food bank could be a good option. A food bank is a non-profit organization collecting and distributing food to hunger-relief charities. (9) At the first step, the supervisors keep close eyes on food quality to match the needs of charities. Then the food bank receives and safely stores the donated food. Finally, they deliver food items to serve individuals who are starving.


Arranging a food bank. Bread and Cakes are placed on the table. Courtesy of 在食物银行看到的面包和蛋糕。感谢提供。



Inedible food waste can be converted into other products such as compost and bioenergy.


Circular usage of food waste. Through conversion by food waste collectors, food waste can be used for organic fertilizer and biogas. Courtesy of (10) 厨余垃圾的循环使用:转化为有机肥和沼气。感谢提供。

Here let me introduce a small German biogas digester named Bio-Ways. It can help user decompose food waste through fermentation by selected bacteria, which could gain fertilizer and biogas for outdoor barbecue and cooking. Compared to simply being dumped at a landfill, this process reduces methane emissions; instead, methane emitted from food waste can be utilized as a source of renewable energy.


For large scale food waste processing, we may need a composting facility. Similar to the processing in small-scale facilities, the food waste transforms into biogas and compost through aerobic decomposition, with additional steps of the press which increase the rate of reaction.


Stages of biogas and compost production. Source: BINE Information Service (11) 堆肥和朝气的产生过程。感谢BINE Information Service提供。



Flow Chart of Circular economy. Courtesy of United Nations Industrial Development Organization. (12) 循环经济的流程图。感谢United Nations Industrial Development Organization提供。

There are several actions to fight against food waste excess, all these are in the chain of circular economy nonetheless. Both planning food waste products and dispensing food to charities are examples of material reduction shown in the chart above. Since the unnecessary supply shrinks and more customer demand increases, the chain becomes balanced. Transformation to sustainable energy and compost can be considered as a way of material reuse. Whether the chain of circular economies functions well depends on the efficiency of each part. Most ideally, higher resource efficiency can yield less waste output and environmental hazard.

这些减少食物浪费的办法都是上图中循环经济的一部分。改善规划或捐献食物,都是在上图所示“Material supply”环节减少浪费。当不必要的物资供应减少和食用需求增长,供需得到平衡。将垃圾转变成能源和堆肥则是资源再利用的方式。循环经济运行是否良好取决于每一部分的功效。最理想的情况下,高度的资源使用效率将产生更少的垃圾和更少的环境危害。














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