Praćenje kvalitete napitaka od žitarica nir spektroskopijom i Briggs-Rauscher-ovom metodom

master's thesis

• Title (english): Monitoring of the quality of cereal drink by use of nir spectroscopy and Briggs-Rauscher's method
• Author: Ivana Ivančan
• Mentor: Jasenka Gajdoš Kljusurić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Process Engineering); (Laboratory for Measurement, Regulation and Automatisation); Zagreb
• Defense date and country: 2015-07-21, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Kontrola hrane je vrlo važan čimbenik u održavanju zdravlja populacije. Sve je veći udio populacije intolerantan ili alergičan na određene komponente u hrani, te je u ovom radu, predmet istraživanja biljni napitak (tzv. biljno mlijeko) dobiveno iz žitarica. U ovom radu korištene su dvije nestandardne mjerne metode kojima se može pratiti kvaliteta proizvoda, a to su blisko-infracrvena spektroskopija tzv. NIR spektroskopija i Briggs-Rauscherova metoda koja se koristi u praćenju antioksidacijskog djelovanja hrane i/ili pića. Analizirani su uzorci napitaka od žitarica (pir, zob, ječam, pšenica, riža) koji su kupljeni i koji su pripremani u laboratoriju. Dio uzoraka je nakon pripreme ostavljen na sobnoj temperaturi, dok je dio spreman u hladnjak (4°C) i snimani su pomoću NIR instrumenta. Svježim uzorcima određena je antioksidacijska aktivnost koja je izražena vremenom inhibicije i BRAI indeksom. Najmanji BRAI pokazuju uzorci kuhanih napitaka od basmati riže i pšenice (BRAI=0,01 mg GAE/100 g) dok je od pripravljenih uzoraka najveći indeks utvrđen za napitak od ječma, s vrijednošću od 0,63 mg GAE/100 g. NIR spektroskopija je uz primjenu kemometrije omogučila razdvajanje uzoraka prema svježini, što potvrđuje primjenjivost ove metode u praćenju kvalitete proizvoda.

Abstract (english)

Food control is a very important factor in maintaining the population health. A growing proportion of the population that is allergic or intolerant to certain components in food is the reason way in this study was investegated vegetable drink obtained from cereals.Two non-standard measuring methods were used to follow the quality of food products, which are the near-infrared spectroscopy (NIR spectroscopy) and Briggs-Rauscher method used to monitor the antioxidant effects of food and / or beverages. The analyzed samples of drink from cereals (spelled, oats, barley, wheat, rice) were purchased and prepared in the laboratory. Part of the samples after the preparation was left at room temperature and the other part was store in the refrigerator (4 °C). The samples were recorded for 7 days using the NIR instrument. For the fresh samples was determined the antioxidant activity that is expressed with the inhibition time and BRAI index. The smallest BRAI showed samples of cooked rice drink (basmati rice) and drink from wheat (BRAI = 0.01 mg GAE / 100 g) and for barley drink was determined the largest BRAI, with a value of 0.63 mg GAE / 100 g. NIR spectroscopy with the use of chemometrics allowed the separation of plant drink according to the freshness, confirming the applicability of this method in monitoring of food quality.

• Keywords: napitak od žitarica; NIR spektroskopija; BR metoda; PCA analiza
• Keywords (english): cereal drink; NIR spectroscopy; BR method; PCA analysis
• Language: croatian
• URN:NBN: urn:nbn:hr:159:372959
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-05 09:30:14