Razvoj procesa osmodehidratacije jabuka

master's thesis

• Title (english): Development in osmo-dehydration process of apples
• Author: Lidija Gracić
• Mentor: Vesna Lelas (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Food Processes Engineering); Zagreb
• Defense date and country: 2007-12-21, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Svrha ovog istraživanja bila je razviti proces kojim će se dobiti sušene ploške jabuka odgovarajućih nutritivnih i poželjnih senzorskih svojstava. Ispitivanja su provedena tretiranjem ploški jabuka u različitim otopinama (0,5%-tnoj otopini limunske kiseline; 40%-tnoj otopini saharoze sa dodatkom 0,5% limunske i 0,5% askorbinske kiseline; vodi) djelovanjem ultrazvuka pri 25°C i blanširanjem pri 80°C. Jabuke su zatim sušene u komornoj sušnici pri 75°C do konstantne mase. Svježim i sušenim jabukama određen je udio suhe tvari, udio prirodnog i ukupnog inverta, udio ukupnih fenola, neflavonoida i flavonoida. Prihvatljivost osušenih jabuka određena je senzorskim i instrumentalnim analizama (boja, tekstura). Najbolja nutritivna i senzorska svojstva pokazale su ploške jabuke tretirane ultrazvukom u 40%-tnoj otopini saharoze sa dodatkom 0,5% limunske kiseline i 0,5% askorbinske kiseline pri temperaturi 25°C.

Abstract (english)

The aim of this study was to obtain dried apple slices with apropriate nutritive and sensory properties. Research was carried out treating apple slices in different solutions (0,5% solution of citric acid; 40% solution of sucrose with 0,5% citric acid and 0,5% ascorbic acid; distilled water) by effect of ultrasound at 25°C and of blanching at 80°C. After that apple slices were dried in an cabinet-type tray dryer at 75°C until constant mass. Dry matter, natural and total invert, concentration of total phenols, concentration of unflavonoids and flavonoids were identified in fresh and dried apples. Hardness and colour of dried samples were determined with sensory and instrumental analysis. The best sensory and nutritive properties showed apple slices treated by ultrasound in 40% solution of sucrose with 0,5% citric acid and 0,5% ascorbic acid at temperature 25°C.

• Keywords: jabuka; osmotska dehidratacija; sušenje; ultrazvuk
• Keywords (english): apple; drying; osmotic dehydration; ultrasound
• Language: croatian
• URN:NBN: urn:nbn:hr:159:803657
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-05 12:01:19