BIOCHEMICAL CHANGES IN APPLES DURING STORAGE

Abstract

Apples (Malus domestica Borkh) are one of the most popular fruits in the world due to their sensory properties and nutritional value. The sensory properties of apples are determined by their chemical composition. Due to the high content of phenolic compounds, apples are considered a potential source of natural antioxidants. Post-harvest storage of apples causes irreversible changes.  Due to the activity of microorganisms or mechanical damage during picking, apples may begin to rot, the hardness of the pulp decreases with longer storage, the taste deteriorates, as the fruits age and their quality deteriorates. By controlling the storage conditions, changes in apple quality can be slowed down.

Apples of winter varieties 'Jonagold', 'Ligol', 'Ariva', 'Gloster', 'Champion' and 'Skaistis' were stored in controlled atmosphere chambers from October 2023 to April 2024. The tests were performed once every six weeks. Natural mass loss, vitamin C content by the standard method and soluble dry matter by the refractometric method were determined. The biggest mass losses were in 'Ariva' apples. During the first month of storage, 62.8 pct. of this variety was lost, and 77.4 pct. during the entire storage period. The lowest mass losses were noted by 'Ligol' 3.1 pct. and 'Jonagold' 3.6 pct. varieties. The highest amounts of vitamin C were determined in October in five out of six varieties of apples. Essentially, the highest amount of vitamin C was accumulated by 'Jonagold' 3.42 mg 100 g^-1 apples, while the lowest amount was found in the February tests of the same variety at 1.72 mg 100 g^-1. The highest amount of soluble dry matter was accumulated by 'Gloster' 14.8 pct., and significantly the lowest by 'Ligol' 10.9 pct.