Varijabilnosti fizikalnih i senzorskih svojstava jaja iz slobodnog uzgoja

master's thesis

• Title (english): Variability of physical and sensory characteristic of free-range eggs
• Author: Tena Stojanović
• Mentor: Ivica Kos (mentor)
• Committee member: Ivica Kos (predsjednik povjerenstva)
• Committee member: Zlatko Janječić (član povjerenstva)
• Committee member: Dalibor Bedeković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Animal Science and Technology); Zagreb
• Defense date and country: 2021-09-23, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Jaja iz slobodnog uzgoja podrazumijevaju jaja od kokoši nesilica koje tijekom dana slobodno borave na zatravljenom ispustu na kojem nalaze dodatni izvor hranjivih tvari što može uzrokovati varijabilnost fizikalnih i senzorskih svojstava jaja. Provedenim je istraživanjem utvrđeno da je svojstvo svježine najvarijabilnije unutar 15 analiziranih svojstava s koeficijentom varijacije (CV) 31,01%, dok je najmanju varijabilnost imalo svojstvo širine jaja (CV=2,77%). Između senzorskih svojstava, boja žumanjka je imala najmanju varijabilnost (CV=15,27%), a svojstvo teksture najveću (CV=21,69%). Hedonističkim senzorskim testom je utvrđeno da se jaja iz slobodnog uzgoja s obiteljskih farmi značajno razlikuju (P<0,05) od jaja iz slobodnog uzgoja iz maloprodaje u boji žumanjka. Nadalje, jednostavnim testom razlika je u 72,23% situacija postignuto uspješno razlikovanje jaja iz slobodnog uzgoja s obiteljskih farmi i iz maloprodaje. Navedeno potvrđuje vrijednost R-indeksa od 77,70% zbog čega možemo zaključiti da se jaja iz slobodnog uzgoja s obiteljskih farmi i jaja iz slobodnog uzgoja iz maloprodaje statistički značajno razlikuju (P<0,05) u senzorskim svojstvima.

Abstract (english)

Free-range eggs are eggs from laying hens that spend their days in grassy fields, which provides an additional source of nutrients that can lead to variability in the physical and sensory characteristics of the eggs. In this study, it was found that freshness was the trait with the highest variability, with a coefficient of variation (CV) of 31.01%, while egg width had the lowest variability (CV =2.77%). Among the sensory traits, yolk color showed the lowest variability (CV =15.27%) and texture the highest (CV =21.69%). The hedonic sensory test revealed that free-range eggs from family farms differed significantly (P 0.05) from free-range retail eggs in yolk color. In addition, panelists were able to successfully discriminate free-range eggs from family farm eggs from retail eggs in 72.23% of the given situations using the same-different test. These results confirm the R-index value of 77.70%. It can be concluded that free range eggs from family farms are statistically significantly (P<0.05) different from free range retail eggs in terms of sensory attributes.

• Keywords: jaja; slobodni uzgoj; fizikalna svojstva; senzorska svojstva; R-indeks
• Keywords (english): eggs; free range; physical characteristics; sensory traits; R-index
• Language: croatian
• URN:NBN: urn:nbn:hr:204:581277
• Study programme: Title: Production and Processing of Meat; Study programme type: university; Study level: graduate; Academic / professional title: magistar / magistra inženjer/inženjerka proizvodnje i prerade mesa (magistar / magistra inženjer/inženjerka proizvodnje i prerade mesa)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2022-11-23
• Created on: 2021-11-23 09:00:00