Glossary of terms

Here you will find definitions of terms used in resources on the Foodsource website. You will also find these definitions on the right-hand side within chapters. If you have any suggestions for new glossary items, let us know here.

2 (1) | A (13) | B (6) | C (15) | D (6) | E (8) | F (12) | G (4) | H (3) | I (7) | L (5) | M (12) | N (7) | O (4) | P (9) | R (7) | S (10) | T (1) | U (2) | W (4) | Y (1) | Z (2)

Photochemical smog

Photochemical smog is observed as a haze in the atmosphere, typically near to cities. It is created through the action of sunlight on pollutants (nitrogen oxides and volatile organic compounds) emitted by automobiles and other industrial sources, which creates other pollutants harmful to health, such as ozone.

Planetary boundaries

The planetary boundaries concept refers to the idea that humans are substantially altering natural systems, and that beyond a certain level of change this may become irreversible and self sustaining. The potential result is a planet with environmental conditions that differ substantially from those in which human civilisation developed and to which many species and ecosystems are adapted. Planetary boundaries have so far been proposed for climate change, biodiversity loss, biogeochemical cycles, ocean acidification, land use, freshwater, and ozone depletion.

Precision farming

Precision farming is an agricultural management practice that aims to supply plants or animals with precisely the amounts of agricultural inputs (e.g. water, pesticides, and fertilisers) they need at a specific location and moment in time, thereby increasing efficiency by reducing the total inputs needed for agricultural production, and reducing environmental impacts. Precision farming uses different types of technologies to measure, observe, and act upon factors that are relevant to the growth of crops and livestock. These can range from big data, GPS, robotics, sensors, and drones, to low-tech measures such as using bottle caps for applying the right amounts of fertilisers to individual plants. Aiming to optimize crop or livestock production, precision techniques include measuring, modelling, and responding to (site-specific) data, including weather forecasts, soil properties, soil water content, pests, and weeds.

Price elasticity

Price elasticity refers to how much the demand for a good is affected by a change in its price. A good is said to be price inelastic if a change in price means that there is little change in demand. An example might be medication or addictive substances, like tobacco. A good is said to be price elastic if a change in price greatly changes the demand for the good.

Processed culinary ingredients

Processed culinary ingredients is a category of food ingredients in the NOVA classification that result from the further treatment of unprocessed and minimally processed foods by processes such as pressing, refining, grinding, milling, and spray drying. Examples include salt, spices, cane sugar, flour, honey and olive oil. Processed culinary ingredients are added to other foods in the preparation of dishes. Advocates of NOVA understand their purpose to be enabling the preparation of more varied dishes from minimally processed foods and improving the taste and appearance of such dishes. Processed culinary ingredients are usually not consumed on their own.

Processed food

The concept of processed food, in the public understanding, is often used loosely to refer to mass-produced ready-to-eat foods such as instant flavoured noodles and soda drinks. The concept, however, also refers to one of the four categories of the NOVA classification, which classifies many of these foods as ultra-processed foods. Within NOVA’s processed food category are minimally processed foods to which one or more processed culinary ingredient has been added, and which have been further modified by processes such as smoking, salting, and canning. Advocates of NOVA understand processed foods to be produced primarily to increase the durability of minimally processed foods and to enhance the taste and appearance of such foods. Examples of processed foods include freshly made breads, pickled vegetables, salted nuts, smoked meats, and canned fish.

Public procurement

Public procurement refers to the acquisition of goods, services or work by public bodies such as government agencies, hospitals, and schools, or by state owned enterprises such as railways or energy providers. Such spending can represent a substantial amount of taxpayers' money and of gross domestic product in many countries, and so how it is spent is a matter of public interest. Beause of this, changing public procurement is often seen as a way in which to influence business practices.

Radiative efficiency

Radiative efficiency is a measure of ‘greenhouse strength’ for different greenhouse gases, defined as the change in radiative forcing per change in atmospheric concentration of a gas (in Watts per metre square per part per billion; W m-2 ppb-1).

Radiative forcing

Radiative forcing is the measure of how different factors (including greenhouse gases) change the balance between incoming and outgoing energy in the atmosphere. Expressed as the change in energy balance per unit area (in Watts per metre square; W m-2) over a given timeframe – typically contemporary compared to preindustrial conditions.

Reconstituted meat

Reconstituted meat is a paste- or liquid-like meat product that is produced from ground meat. Fat and excess water are separated from the meat using a centrifuge or an emulsifier (a machine used to produce the meat into a fine and homogeneous paste or liquid of a desired thickness). Reconstituted meat is mostly used as a basis for pet food and as a supplement in some meat products for human consumption (e.g. chicken nuggets and some sausages).

Reduction fishery

A reduction fishery catches wild fish to be converted into fishmeal and fish oil (often to supply the aquaculture sector), rather than catching fish for direct human consumption.


Reformulation refers to changes food manufacturers make to the production recipes of processed and ultra-processed food products to improve their nutritional profile. Examples of reformulation include replacing sugar with artificial sweeteners (e.g. aspartame or sucralose) to reduce the food’s energy content or reducing the amount of salt or saturated fat in a food product.


The concept of resilience, in the context of food system sustainability, refers to the ability of the food system to cope with and recover from socio-economic or environmental shocks and pressures. A resilient system has a certain degree of toughness and is able to bounce back against or adapt to disturbances. A resilient food system, for example, is able to keep providing food or other outputs such as livelihoods for farmers, drinking water, and biodiversity conservation under conditions of drought, a drop in food prices, war, climate change, the spread of virus in plants or animals, and so on. Resilience can be thought of at different scale levels. For example, what may be considered as resilient on a national level may not be understood to be resilient at a farm level. While some see resilience as synchronous with sustainability, others point out that a resilient system may also be one that resists needed transformation; an unsustainable status quo may in fact be resilient to change.


A ruminant is a mammal with a four-compartmented stomach which enables it to acquire nutrients from plant-based food such as grasses, husks, and stalks. Examples of ruminants include cattle, sheep, goats, deer, giraffes, and camels. After swallowing, microbes in the ruminant’s rumen (its first stomach compartment) begin fermenting the food. This process generates fatty acids (nutrients which the ruminant absorbs through its rumen walls) and methane, which the ruminant eructs or burps. Through this process, ruminants are able to digest coarse cellulosic material which monogastrics and people cannot. Methane emissions from ruminants are a significant source of greenhouse gasses from ruminant-based livestock systems.

Selective breeding

Selective breeding refers to the deliberate human practice of choosing which plants or animals to breed together, based on specific characteristics, in order to selectively enhance these characteristics (and their genetic basis) in their offspring.