Environmental Engineering Reference
In-Depth Information
Table 3.8
Potential environmental impacts in the production of 1 kilogram of selected enzymes produced
by Novozymes at the factory gate in Denmark.
Impact category
Units
Termamyl
120 L
Spirizyme
plus FG
Ronozyme
P5000 CT
Savinase
12 TXT
Novamyl
10,000 BG
Global warming
g CO
2
eq.
1,000
7,500
2,000
4,250
10,200
Acidification
g SO
2
eq.
5
24
6
14
29
Nutrient enrichment
g PO
4
eq.
2.0
22
2.5
0.5
7.0
Photochemical
ozone formation
g ethylene eq.
0.6
2.7
0.7
1.2
3.0
Energy consumption
MJ
12
87
35
65
125
Use of agricultural
land
m
2
year
0.4
3.5
0.3
0.4
2.0
Termamyl 120 L
: Bacterial alpha amylase used for liquefaction of starch in the production of high-fructose syrup.
Spirizyme plus FG
: Fungal glucoamylase used for saccharification of starch in the production of starch derived sugars.
Ronozyme P5000 CT
: Fungal phytase used for the release of phytate bound phosphate in the preparation of animal feeds
(pig, poultry, farmed fish).
Savinase 12 TXT
: Bacterial protease used in detergents for the removal of protein stains.
Novamyl 10,000 BG
: Bacterial amylase that diminish the crystallization of starch used as an anti-staling agent in industrial
bread production.
Adapted from Nielsen et al., 2007, and reproduced with permission from Springer.
However, data of Table 3.8 comes from a cradle-to-gate analysis that indicates the impact
per kilogram of enzyme. For a more accurate analysis, the impacts should be based on
enzyme activity instead of weight. However, for enzymes that perform different functions,
as the ones presented in Table 3.8, it is not possible to perform a comparative analysis.
Another important observation about the data presented in Table 3.8 is the high correlation
coefficient between energy consumption and global warming (R
2
= 0.9759) and energy con-
sumption and acidification (R
2
= 0.9488), which indicates that global warming potential and
acidification are most likely caused by the production of energy.
Impact of packaging
The description of the environmental impact of packaging is presented in Chapter 12.
Impact of processing
Food processing is highly diverse in terms of processes and raw materials, and so are the
environmental impacts produced by each type of food industry. Depending on the raw mate-
rial and the degree of processing every food product requires, the magnitude of the impact will
vary at different stages of the supply food chain.
The overall impact of food products varies on a product-to-product basis, and to illustrate
the idea, the potential impact on climate change at five stages of the supply chain will be ana-
lyzed for the following products: tomato ketchup, organic potatoes, medium-fat milk, bread,
and bone-free pig meat. Data for this example were obtained from published papers on life
cycle assessment for these five products in Europe.
Figure 3.7 presents the grams of carbon dioxide equivalent per kilogram of product at the
agriculture stage, processing, packaging, transportation, and consumption. The first observa-
tion is that for both animal products, milk and pig meat, the highest impact occurs at the agri-
cultural stage with 84 and 88 percent respectively. At the opposite end of the spectrum, organic
potatoes show to have the highest impact during transportation and consumption. Cooking
potatoes takes significant amounts of energy with the associated emissions of carbon dioxide.
