April 12, 2021

Correct Management of Food Waste

Many people fail to manage food waste properly, because they believe that this type of waste decomposes quickly in the environment, causing no harm, due to the organic nature of much of this waste.

However, this is not quite how it works!

Just as we worry about plastics, metals, papers, and other types of garbage, we should also worry about food waste.

Let’s talk about quantity. Do you know how many tons of food waste is produced every day?

You never stopped to think about it, did you?

So, let’s think about the following: a restaurant in an industry, which makes lunch daily for 500 employees. The food handled and served there goes through at least four stages:

1st Stage: Receiving the food sent by the suppliers.
In this stage the food is sorted, and those that are past due or do not meet the required quality standards are discarded. Thus, kilos (or even tons) of residues are generated from crushed, rotten food, leaves, badly refrigerated meat, etc.

2nd Stage: Food pre-preparation
This stage involves washing, peeling, cutting and disinfecting the food. At this point, many inedible parts of the food are discarded (stems, fat, peel, seeds, grains, bones, etc.).

3rd Stage: Preparation and cooking
In this stage, the food is cooked and prepared to be served to the final consumer. Here, one notices the generation of residues such as oil, leftovers that remain at the bottom of the pots, pans and other utensils. Not to mention the food that ends up falling on the floor and can no longer be consumed.

4th Stage: Distribution of the finished food
This is the moment when the food is made available to those who will consume it. At this moment, two types of food waste are generated: clean leftovers, which are those that remain in the buffets and are not consumed, but end up being contaminated after the consumer’s contact, through breathing, talking and moving over the food; and the so-called leftovers-indigestible, which are the remains coming from the consumer’s plate.

Through this analysis of the steps that occur daily in the premises of an industrial kitchen, we can get an idea of the tons of food waste that are produced every day in the country. And, by the way, obviously this reality also occurs in bars, restaurants, and street snack bars that handle and sell food products.

And, speaking of concrete statistics, the National Solid Waste Plan, directed by the Ministry of Environment, disclosed that annually, the country produces about 800 million organic waste, among which food waste disposal is the most significant.

But all this food waste, in theory, is quickly decomposed in the soil. So what impacts does this waste have on the environment?

Because it is organic in nature, the decomposition of food waste produces a chemical phenomenon called “anaerobic degradation”, which is nothing more than bacteria digesting that waste in a place where the presence of oxygen gas is scarce.

This chemical phenomenon contributes to the generation of methanol, which is extremely toxic to environmental and human health, as well as contributing to global warming due to its large release into the atmosphere.

The anaerobic degradation also generates leachate, which is a black liquid with an unpleasant odor that comes out of the garbage and causes great impacts on the soil, such as the reduction of its useful life and high probability of contamination of groundwater and surface water.

We can also see that the large amount of food waste produced daily overloads garbage dumps and municipal landfills, and causes an increase in the proliferation of urban pests such as cockroaches, rats, and other animals that transmit diseases to man.

But after all, how should the correct management of food residues be done?

Firstly, there must be the correct separation and conditioning of this type of waste from the others. Isolating this type of waste from the others helps to ensure that its destination is as correct as possible. In addition, if coupled without proper separation, the high humidity presented by food waste can hinder the recycling of many residues, such as paper and cardboard, which will no longer be attractive waste for recyclers.

Thus, once the food residues have been separated and correctly conditioned, they can be disposed of as follows:

  • Incineration
    Cost: High

Advantage: It is excellent from the sanitary point of view, since incinerated waste no longer takes up space in landfills.

Disadvantages: If not done in a sustainable way, incineration can release dangerous gases into the atmosphere.

  • Landfill
    Cost: Low

Advantage: It is the most accepted form of disposal for food waste, both in social and legal aspects.

Disadvantages: The decomposition of food in landfill generates toxic gases to the soil and the atmosphere. For this reason, it is of indispensable importance that municipalities and environmental agencies take measures to minimize these negative impacts, such as the correct sealing of the soil at the site, and other precautions.

  • Composting
    Cost: Low

It is sustainable and able to minimize several environmental complications, since the waste, after going through rigorous stages of control, is reused, and no longer occupy space and harm the environment in dumps and landfills.

Disadvantages: it can cause salinity in the soil if it is not carried out in a correct and responsible manner.

Thus, of the three destination options, composting is the most indicated when the subject is environmentally responsible destination. For this reason, many companies currently send their organic waste to third party companies that perform composting, an attitude that, in addition to protecting the environment, also generates income and opportunities within these waste treatment companies.