Food Waste represents a large percentage of the waste steam for many industries. The main sectors are restaurants, hospitals, nursing homes, food manufacturing, processing facilities, supermarkets, schools, hotels, Catering Halls, food courts and many other locations.
There is growing pressure for removing the organic waste from landfills. For establishments that serve food there is an average of 1 pound of waste per meal served by considering both pre-sale and post-sale waste.
Below is a brief overview of some of the ways to address food waste. Of course the solution for each industry and even each facility within the same industry will vary depending upon many factors.
Waste Reduction at the Source
- Conduct a Waste Audit
A waste audit or waste analysis can give you valuable information about your waste processing practices, as well as a roadmap for setting priorities and making prudent decisions that are based on efficiency versus guesswork. The waste audit can be as basic or as detailed. Therefore, the point is to perform some type of waste audit that can be used as a basis for decision-making.
- Reduce Pre-Sale Food Prep Waste
This is all the kitchen waste that is generated prior to the sales to customers. About 10% of the food purchased ends up becoming Pre-Sale food waste. To control waste during the food prep stages some suggestions are as follows:
- Be aware of the quantity and timing of ordered food.
- Re-think production and handling practices;
- Try to observe and pinpoint where most of the waste is occurring in the preparation process
- Take a look at the menu if certain items or groups of items account for most of the excess waste in the preparation stages.
- Check out possibilities for donating any excess prep waste to local food shelters.
- Reduce Post-Sale Food Waste
This mainly involves waste from plates and order returns. Some suggestions for controlling this waste include:
- a) Removing trays from the process so that patrons do not have a tendency to pile food up on the tray.
- b) Controlling the size of the portions given to patrons.
- c) Modifications to the menus based on close observations by the staff.
Food Recovery for the Needy
There are 2 basic categories of food recovery for the needy.
- Perishable and Prepared Foods
This involves the collection of food waste during the food prep stages at facilities such as restaurants, food caterers, supermarkets, hospitals, nursing homes, schools, etc. and distribution to the needy through national groups such as Food chain.
- Non-Perishable Food Donations
This involves the collection of processed foods that have a long shelf life and distribution through networks such as Second Harvest.
Secondary to Food Recovery and Feed the Hungry programs there is a need to make food discards available for feeding animals. This could involve provisions for farmers, zoos and many other applications. Converting food discards to animal feed and pet food is fairly common and is a great option for recycling food scraps.
Oftentimes food waste is the raw material in rendering industry for converting these materials to soaps, cosmetics and even biodiesel fuel. Biodiesel is an alternative fuel produced from virgin oils, cooking oil and other biowaste feedstock.
Biodiesels are biodegradable and nontoxic. In addition, it helps reduce the clogging of pipes and costly sewer issues that can extend to public sewer lines and wastewater treatment facilities.
Composting and Food Waste Drying Systems
When considering On-Site composting or Food Waste Drying Systems there are several questions that are important, such as:
- Space Availability.
- Staff Resource for separating food scraps from trash as well as operating the equipment etc.
- Infrastructure availability (whether it is just electrical requirements or sewer considerations).
- End Use for the finished product.
- Local support and cooperation or obstacles from nearby businesses or residences and.
- Approvals from local enforcement agencies.
The most common on-site methods In-Vessel Composting; Vermi composting and Anaerobic Digestion.
This process involves temperature, moisture and aeration controlled systems where organic materials are fed into equipment. This system has mechanisms for turning or agitating the material for proper aeration.
This type of system can generally process large amounts of waste without taking up too much space and can accommodate almost any type of organic waste. The process is fairly quick and can take as little as a few weeks (however for the microbial activity to stabilize into a finished compost it can take several more weeks or months).
Hence, available land space, as well as haulers and end users in your area will help you decide which is better for you. Some in-vessel systems are fully automatic with sensors to monitor temperature, oxygen, and moisture. They use biofilters to reduce or eliminate odors. Hence, this is a good method for institutions with large amounts of compostable materials and limited space.
With this process, worms break down the organic materials. Animal products cannot be composted using this method but this process can break down organic materials into high value compost faster than In-Vessel composting.
This process involves breaking down organic matter in an oxygen-free environment in order to generate biogas. The biogas is a combination of methane and carbon dioxide. The methane is an energy source.
The material that remains after digestion (digestate) should then be composted aerobically to complete the process and produce a valuable soil amendment.
In addition to energy production, these systems require less space than many other large-scale composting methods and are easier to locate in urban areas.
Advantages of food waste drying systems
Food Waste Drying Systems can provide a fast, simple and user friendly onsite process for decomposing and dehydrating food scraps into rich soil sediments. Another benefit of Food Waste Drying Systems is that they do not require any micro-organisms, enzymes, fresh water or other additives.
In addition, they can be configured to extract animal oil for high quality biodiesel refinement. Throughput capabilities range from 60 pounds to 100+ tons per day.
The size of a 60 lb per day system only requires a footprint of approximately 9 square feet. On the other hand, system capable of processing 2,400 lbs per day requires roughly 72 square feet of floor space (12′ x 6′).
For large scale food waste it is important to initiate an analysis of the waste stream and existing circumstances to properly evaluate the various alternatives. The above practices are becoming more and more commonplace and the trend is expected to accelerate at an even faster pace in the near future.
Syed Shoaib Bukhari, M.Sc (Hons.) Food Technology, UAF.
Muhammad Kamran Zahoor, M.Sc (Hons.) Food Technology, UAF.
Muhammad Hassan, M.Sc (Hons.) Food Technology, UAF.
Summar Fatima, M.Sc (Hons.) Human Nutrition and Dietetics, UAF.