Browning Lab Report

Introduction: The purpose of this lab is to see how the colour of an apple would change (browning) over time, when placed in different conditions. When referring to the term “browning”, it is meant to imply the change of colour that occurs inside the apple, giving an appearance that is distasteful (Di Guardo et al., 2013). Specifically, within this lab the apple was cut into 4 pieces with 3 pieces being placed on a weigh boat, and a 4th piece placed in a beaker of water. These weigh boats were then set in 4 separate areas with a set condition for the apple: air, water, lemon juice, and open environment.
Materials and Methods:
1. Apple was first cut into 4 separate pieces and 3 pieces were placed on a weigh boat
2. Each weigh boat was then
On the other hand, the apple soaked in lemon juice and the apple placed in the beaker of water had less colour change occur on them compared to their counterparts. Another trend that was noticed is that gradually over time all the apples did turn brown by the end. This can be seen in Table 1 where browning is recorded in all set positions. Within apples and many other fruits is an enzyme known as polyphenol oxidase (PPO). Through the process of oxidation, discolouration occurs within the apples as browning is correlated to enzymatic activity, such as polyphenol concentration and other factor of conditions that change optimality of an enzyme (Burda, Oleszek, & Lee, 1990). In the experiment, the apples were cut, which exposed the slices to a set of different conditions, in which the enzymes would differ in the speed of carrying out the chemical reaction (Son, Moon, & Lee, 2001). Prior to conducting the experiment, predictions were made to see in which conditions would the apple turn “brown” the most. From common knowledge, the prediction was made that the apple placed in the open environment would turn brown the most which did occur when analyzing Table 1. The other prediction stated was that the apple slice kept in the fridge, would be the least to turn brown, as it
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Di Guardo, M., Tadiello, A., Farneti, B., Lorenz, G., Masuero, D., Vrhovsek, U., . . . Costa, F. (2013). A multidisciplinary approach providing new insight into fruit flesh browning physiology in apple (malus x domestica borkh.). PloS One, 8(10), e78004. doi:10.1371/journal.pone.0078004 [doi]
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Son, S., Moon, K., & Lee, C. (2001). Inhibitory effects of various antibrowning agents on apple slices. Food Chemistry, 73(1),