Methods for food shelf life determination and prediction - Oxidation in Foods and Beverages and Antioxidant Applications - page 204

where I ox0 is the value of the food quality indicator just after production, I ox is
the quality indicator value corresponding to the acceptability limit.
Since oxidation reactions are highly complex and there are a huge number of
factors potentially affecting the reaction rate, it should be stressed that the
evolution of any oxidation indicator versus time can be frequently the result of
different reactions taking place simultaneously or consecutively. Thus, the
reaction order n does not give any indications on the true reaction mechanisms
involved and k is therefore considered as an `apparent' rate constant. A number
of papers dealing with this well-recognized procedure have produced huge
amounts of data on the oxidation rates of several foods in different
environmental conditions. Table 9.6 reports some examples of recent literature
data relevant to the reaction order of selected oxidation indices in different food
products. Due to the huge number of literature data available on the kinetics of
oxidative reactions, Table 9.6 should not be considered exhaustive.
Table 9.6 shows that zero and first order are frequently applied to describe
the changes of oxidation indicators. However, due to the complex pathway of

Table 9.6 Examples of apparent reaction orders used to describe the evolution of
oxidation indicators

Apparent Index Product

reaction order
(n)

Zero Peroxide value Potato chips (Houhoula and Oreopolou,

2004); Biscuits (Calligaris et al., 2007a);
extra virgin olive oil (Calligaris et al., 2006;
Mancebo-Campos et al., 2008); salmon oil
(Huang and Sathivel, 2008)

K232 Extra virgin olive oil (Mancebo-Campos et

al., 2008)

First Vitamin C Frozen vegetables (Giannakourou and

degradation Taoukis, 2003); orange juice (Polyedra et

al., 2003; Tiwari et al., 2009); fresh-cut
strawberries (Odriozola-Serrano et al., 2009)

K270 Extra virgin olive oil (Gutierrez and

Fernandez, 2002; Mancebo-Campos et al.,
2008)

Oxygen Soybean oil (Colakoglu, 2007)

consumption

Other Peroxide value Bread sticks (Calligaris et al., 2008); bulk

oils (Aragao et al., 2009)

Anthocyanins Fresh-cut strawberries (Odriozola-Serrano et

al., 2009)

Volatile Olive oil (Kanavouras et al., 2004)

compounds
Carotenoids Frozen tomato puree (Calligaris et al., 2004)

Vitamin C Orange juice (Manso et al., 2001)