Utjecaj tretmana ultrazvukom visokog intenziteta na kvalitetu i stabilnost minimalno procesiranog krumpira

master's thesis

• Title (english): Effect of high intensity ultrasound treatment on the quality of minimally processed potatoes
• Author: Josip Bebek
• Mentor: Branka Levaj (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2018-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada bio je istražiti utjecaj vremena tretmana ultrazvukom visokog intenziteta na kvalitetu i stabilnost minimalno procesiranog krumpira (MPK) tijekom 8 dana skladištenja. Krumpir je oguljen i narezan na ploške, tretiran u kupelji u otopini natrijeva askorbata te je pakiran u vakuumu i skladišten na 10 °C. Krumpir je tretiran ultrazvukom frekvencije 40 kHz i amplitude 100% tijekom 3, 10, 20, 30 i 40 minuta. Tijekom skladištenja MPK, 1., 3., 5., i 8. dan pratila se ukupna suha tvar, topljiva suha tvar, pH vrijednost, boja, tekstura, udio plinova u pakovanju i senzorska ocjena. Na ukupnu suhu tvar i topljivu suhu tvar najveći utjecaj je imalo vrijeme skladištenja i toplinska obrada. Tretman ultrazvukom utjecao je na sniženje pH tijekom skladištenja. Udio plinova u pakovanju najviše ovisi o duljini skladištenja. Svi tretirani uzorci tijekom cijelog skladištenja imaju višu vrijednost svjetline L*. Tretiranim uzorcima se vrijednost elastičnosti povećava tijekom skladištenja, dok su ostali parametri teksture nepromijenjeni pod utjecajem tretmana i skladištenja. Tretman od 20, 30 i 40 min je imao utjecaj na pojavu nekarakterističnih i stranih okusa i mirisa tijekom skladištenja, a za sprečavanje posmeđivanja efikasnim su se pokazali svi tretmani neovisno o vremenu trajanja. Najefikasnijim za održavanje ukupne kvalitete MPK se pokazao tretman od 3 minute.

Abstract (english)

The aim of this study was to evaluate the effect of high intensity ultrasound treatment duration on the quality of minimally processed potatoes (MPP) during 8 days of storage. The potatoes were peeled, sliced to chips, treated in a bath with sodium ascorbate, vacuum packaged and stored at 10 °C. Potatoes were treated with 40 kHz frequency and 100 % amplitude ultrasound for 3, 10, 20, 30 and 40 minutes. During the storage of MPP, quality was monitored on the 1st, 3rd, 5th, and 8th day. Dry matter content, total soluble solids, pH, colour, texture, sensory analysis and gas composition of the packaging were monitored. On the dry matter and total soluble solids content, length of storage and cooking had the biggest effect. Ultrasound treatment caused a reduction in pH levels during storage. Gas composition of the packaging mostly depended on the length of storage. All of the treated samples showed higher values of brightness, L*. The elasticity of treated samples increases during storage while other texture parameters remain unchanged. All of the treated samples had good sensory evaluation scores on the prevention of browning but treatment time of 20, 30 and 40 minutes had an effect on the appearance of uncharacteristic and unknown tastes and smells during storage. Treatment time of 3 minutes was the most efficient in preserving the overall quality of MPP.

• Keywords: krumpir; minimalno procesiranje; enzimsko posmeđivanje; ultrazvuk; boja; senzorska ocjena
• Keywords (english): potato; minimally processing; enzymatic browning; ultrasound; color; sensory evaluation
• Language: croatian
• URN:NBN: urn:nbn:hr:159:230748
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-11-20 09:55:22