Fruit leather production from goldenberry (Physalis peruviana L)

In this thesis a tropical fruit cape gooseberry which have opportunity to grown in our country, used to the produce fruit leather. Fruit leather is easily consumed and nutritional values are concentrated. Fruit leathers were studied with different starch concentrations and final concentrations was determined. After that fruit leather's physicochemical, functional, microbiological, sensory and storage stability properties were investigated. These values were determined on different temperature degrees (60 ̊C, 70 ̊C and 80 ̊C) in drying cabinet and sun drying.The results showed, total phenolic content of fruit leathers which dried in the drying cabinet increased statistically significant (p<0,05) when the higher the drying temperature. Total phenolic contents of sun dried fruit leathers have close values to fruit leathers which dried in the drying cabinets. The total carotenoid losses in processing for fruit leathers dried temperature of 80 ̊C higher than fruit leathers dried at temperature 60 ̊C and 70 ̊C. Total carotenoid contents of sun dried fruit leathers statistically significant (p<0,05) higher than fruit leathers which dried in the drying cabinets. In terms of vitamin C contents in dry base, there is no statistically difference (p>0,05) fruit leathers dried at temperature of 70 ̊C between other samples. However, the vitamin C loss of samples dried at 80 ̊C statistically significant (p<0,05) higher than loss of samples dried at 60 ̊C. Antioxidant activity values determined as DPPH free radical scavenging activity inhibition values. DPPH values of fruit leathers which dried in the drying cabinet decreased statistically significant (p<0,05) when the lower the drying temperature. Gallic acid, vanillin, p-coumaric acid, ferulic acid, rutin and cinnamic acid phenolic compounds were determined fruit and fruit leather samples. There are no statistically difference (p<0,05) between gallic acid, vanillin, p-coumaric acid and ferulic acid contents of fruit leathers dried on different temperatures in drying cabinet. Gallic acid and vanillin contents of sun dried fruit leathers lower than fruit leathers which dried in the drying cabinets. Another phenolic compounds rutin was statistically significant (p<0,05) higher in samples drying at 60 ̊C than the other samples. Cinnamic acid was statistically significant (p<0,05) higher in samples drying at 80 ̊C than the other samples. α-carotene and β-carotene contents of samples dried at 70 ̊C statistically significant (p<0,05) higher than samples dried at 60 ̊C and 80 ̊C. There is no statistically difference (p>0,05) between β-carotene contents of sun dried fruit leathers and fruit leathers which dried at 70 ̊C in drying cabinet. But α-carotene contents of sun dried fruit leathers lower than samples dried at 70 ̊C. Sucrose, glucose and fructose are major sugars which determined in fruit and fruit leather samples. Glucose and fructose contents of fruit leather which dried in the drying cabinet increased statistically significant (p<0,05) when the higher the drying temperature. Sucrose contents of samples dried at 80 ̊C statistically significant (p<0,05) lower than samples dried at 60 ̊C and 70 ̊C. There is no statistically difference (p>0,05) between sucrose contents of fruit leathers dried at 60 ̊C and fruit leathers dried at 70 ̊C. Fruit leathers remained stable in terms of microbiological, for a period of six months. Phenolic compounds amounts decreased significant during storage. α-carotene and β-carotene contents decreased significant during storage too. Some changes occured sucrose, glucose and fructose contents during storage. But that changes were not significant unlike losses ocurred values of phenolic compounds or α-carotene and β-carotene.