Thursday, July 28, 2011

Lifecycle Assessments of some common food products

Yesterday I wrote about the lifecycle assessment methodology created by The Center for Sustainability and Excellence, which is based on international standards and is used in the assessment of various products and services on behalf of companies who would like to verify and possibly "ecolabel" products as green or even carbon neutral.

Today, I am going to list several common food products and evaluate the general results of their lifecycles. For the most part, these include some of the most important industrial and agricultural food products in the world. As you will see, their highest impacts occur at many of their stages including raw material extraction, transportation, manufacturing, distribution, use and disposal; in other words, impacts occur across the lifecycle from "cradle to cradle." (This term was adapted from the "cradle to grave" to account for the more recently included use and disposal stages, creating a full-cycle loop and thus allowing for the incorporation of the concept of the closed-loop-systems-based thinking.)


1. Bread

Bread is one of the most important industrial foods products, and producing it is obviously a huge part operations of bakeries like Butternut, Bimbo, Wonderbread, Chicago's own Prairie City Bakery, among others(assuming part or all of the bread making isn't sourced out).

According to the Journal of Food Engineering, organic production of wheat combined with industrial milling and a large bread factory is the most environmentally efficient way to make bread. Primary production(not sure whether this includes crop production or bread production) and transportation were the 2 most impactful stages. Baking consumed a high amount of energy and cultivation accounted for a lot of eutrophication in the form of nitrogen leakage from fields, emission of nitrogenous compounds in the production of fertilizers, and use of tractors.

2. Beer

America's second favorite carbohydrate! I was pleased to see this included in the Journal study. Bottle production seemed to be very high impact, which is why Goose Island's Green Line Pale Ale is only served from barrels. Other stages which accounted for high emissions were packaging and beer production, filtration, fermentation, storage, and harvesting and transport of cereals. The Journal cited various sources which used conflicting system boundaries, so if anybody has a better study on the LCA of beer, please share!!

3. Dairy

Milk production, like most food production methods, is inevitably going to lead to a conversation about conventional vs organic. Conventional uses less land, while organic uses less pesticides. If you have to use conventional methods, some suggestions are using regionally or domestic produced feeds and less use of pesticides in imported concentrated feeds. For organic, the suggestion was to use more concentrated feed, and the cultivation of higher-yielding crops. Another overall suggestion was the scheduling of products to reduce milk waste from frequent product changes. The agricultural phases are the most significant. Also of importance are waste management, packaging, and cleaning processes. The main impacts of dairy production are high water usage, high amounts organic waste, and energy use.


3. Meat production:

Beef, as you might know, has the highest environmental impacts, whether it's measured per energy unit produced or per pound. Chicken is the most efficient, unless it's measured in terms of energy produced. In this case, pork is more efficient. The main reason for beef being inefficient is the greater feed conversion ratio(mass of feed consumed divided by gain of body mass). As with milk, most of the impacts environmentally are found in the agricultural production in the lifecyle of meat products. Interestingly, organic farming was found to increase global warming impacts as well as land requirements, with the exception of sheep production. Some suggestions for a better LCA would be shorter feeding lengths, replacement of soya meal feed by pea and rapeseed-cakes for pork production, and the introduction of green legumes in intensive crop rotations with high proportion of cereals and nitrogen fertilizer. If you're doing a strictly 'greenhouse gas emissions' lifecyle analysis, it should be emphasized that major sources from meat production are from gut emissions(CH4) from livestock and N20 emissions from feed(crops) production.


If you would like to have an LCA performed on any of your products or operations at your company, please contact the Centre for Sustainability and Excellence, kikos@cse-net.org or visit http://www.cse-net.org/Contents.aspx?CatId=47.


Note: All information for this article was sourced from the Journal of Food Engineering, Volume 90, Issue 1, January 2009, Pages 1-10.

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