Fizikalno-kemijska i senzorska svojstva obogaćenih praškastih mješavina na bazi kave

doctoral thesis

• Title (english): Physical, chemical and sensory properties of enriched, coffee based powder mixtures
• Author: Maja Benković
• Mentor: Ingrid Bauman (mentor)
• Committee member: Damir Ježek (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; Zagreb
• Defense date and country: 2013-11-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 663 - Industrial microbiology. Industrial mycology. Zymurgy, fermentation industry. Beverage industry. Stimulant industry

Abstract

Tri tipa praškastih mješavina na bazi kave – cappuccino, instant kava i mljevena kava, obogaćivani su funkcionalnim sastojcima – vitaminom A, vitaminom C, željezom i inulinom, sa svrhom dobivanja novog, funkcionalnog proizvoda te utvrđivanja utjecaja funkcionalnih dodataka na fizikalna, kemijska i senzorska svojstva tako dobivenih obogaćenih mješavina. Obogaćene mješavine skladištene su 12 mjeseci pri sobnim uvjetima u tripleks i limenoj ambalaži. Analizom fizikalnih svojstava utvrđen je značajan utjecaj vremena skladištenja na sadržaj vlage u uzorcima te njihovu nasipnu gustoću. Reometrijskom metodom utvrđene vrijednosti indeksa kohezije kategoriziraju cappuccino mješavine i mješavine mljevene kave kao vrlo i izrazito kohezivne, dok se kohezivnost instant kave protezala od kategorije lakog tečenja do izrazite kohezivnosti, do čega je došlo zbog loma aglomerata. Kod svih je mješavina utvrđena proporcionalnost između indeksa kohezije, koeficijenata sabijanja i omjera visine stupca kolača. Funkcionalni su dodaci najbolje očuvali kvalitetu cappuccino mješavina nakon 12 mjeseci skladištenja, dok je vrsta ambalaže najviše utjecala na indeks kohezije svih promatranih mješavina. Nakon 12 mjeseci skladištenja utvrđena je prisutnost vitamina A u obogaćenim mješavinama, što govori u prilog prihvatljivosti mikroinkapsulacije kao metode očuvanja stabilnosti vitamina dodanih u praškaste mješavine na bazi kave.

Abstract (english)

Three types of coffee-based powder mixtures – cappuccino, instant coffee and ground coffee were enriched with functional ingredients – vitamin A, vitamin C, iron and inulin, with a purpose of producing a new functional product and defining the influence of functional ingredients on physical, chemical and sensory properties of newly developed mixtures. Enriched mixtures packed in triplex bags and tin cans were stored for 12 months at room conditions. Physical property analysis revealed a significant influence of storage time on moisture content and bulk density of the mixtures. Rheometrically determined flow properties define the cappuccino and ground coffee mixtures as very or extremely cohesive powders, while instant coffee mixtures showed a great variety of cohesion properties, ranging from free flowing to extremely cohesive, due to agglomerate brakeage. All the mixtures exhibited a proportional relation between cohesion indexes, compaction coefficients and cake height ratios. Functional ingredients preserved the quality of cappuccino mixtures after 12 months of storage and the packaging material had the greatest influence on cohesion index values of the mixtures. Vitamin A was present in all the enriched mixtures after 12 months of storage, which confirmed the suitability of microencapsulation for preservation of vitamins added to coffee mixtures.

• Keywords: kava; obogaćene praškaste mješavine; funkcionalni dodaci; svojstva tečenja praškastih mješavina; kemijska svojstva; senzorska svojstva
• Keywords (english): coffee; enriched powder mixtures; functional ingredients; powder mixture flow properties; chemical properties; sensory properties
• Language: croatian
• URN:NBN: urn:nbn:hr:159:418909
• Promotion: 2014-07-06
• Study programme: Title: Food Technology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti (doktor/doktorica znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2018-05-17 09:57:50