Lye peeling of 'Tombul' hazelnuts and effect of peeling on quality

Hazelnuts were lye peeled and the peeling time (2-12 min), temperature (63-97degreesC) and NaOH concentration (40-140 g NaOH kg(-1) peeling solution) effects on peeling and quality were investigated. Increases in both temperature and concentration of lye solution led to a decrease in peeling time. Moisture content of samples were changed significantly (P98%, 0.45 mm penetration depth, 7.1 g titratable NaOH kg(-1) and a Hunter-L value of 52.93. The quality parameters of peeled hazelnuts at this given combination, such as protein, oil, free fatty acid, ash contents, peroxide number and L values showed no significant change if compared with untreated control samples

Studies on caustic peeling of apples

Effects of temperature, concentration of NaOH solutions and immersion time on caustic peeling of apples were studied. NaOH solutions of 6, 9, 12 and 15% were heated to 60, 70, 80, and 90 degrees C at various immersion times were used, until more than 98% peeling was achieved. Temperature of caustic solution versus immersion time plot showed a linear trend. Concentration of the caustic solution changed linearly with respect to immersion time. Increase in both temperature and concentration reduced the immersion time needed for efficient peeling