Effects of storage conditions on the lipid composition of commercially prepared orange juice

Orange juice quality with an emphasis on flavor components

“…These fatty acids are important as precursors to offodors and off-flavors. 80 These observed changes in citrus lipids follow the general pattern, vis., partial or complete hydrolysis of the lipids (phospholipids) to fatty acids and other components, followed by oxidation of unsaturated fatty acids as proposed for juice. Direct oxidation of the unsaturated acids (autoxidation) or other unsaturated coriiponents in the lipid fraction, e.g., terpenoids or carotenoids, followed by hydrolytic or chemical degradation may also occur.…”

“…Earlier work indicated that the most striking difference in fresh and aged Valencia juice was a decrease in the phospholipid content to 10% of its original value, a similar decrease in lipid nitrogen to 20%, and the complete disappearance of lipid choline.™- 80 Commercial orange juice held in storage at elevated temperatures accumulate unesterified, unsaturated fatty acids. These fatty acids are important as precursors to offodors and off-flavors.…”

Thermally Degraded Flavors in Citrus Juice Products

“…He concluded that the suspended matter was responsible for much of the characteristic flavor but also contained precursors of the storage-developed off-flavors. Nagy and Nordby (16) studied the effects of storage temperatures and duration on the different lipid classes of single-strength orange juice, and found extensive degradation of phospholipids. Examination of TLC profiles of the phospholipid fraction did not show formation of any lyso-derivative.…”

Lipids in citrus fruit juice. 1. Lipid content during orange ripening in eastern Sicily

“…The sample of crude lipids obtained was purified on a Sephadex column as described by Wuthier (1966). Two different methods for acid esterification were tested: one using boron trifluoride (Nagy and Nordby, 1970) and the other with acetyl chloride-methanol (1:20, v/v) at 50 "C for 1 h (Lillington et al, 1981). Both methods gave the same recoveries; Lillington's method was preferred because BF3 could cause damage to both glass and column-packing material (Lillington et al, 1981).…”