Utjecaj karakteristika sirovine i procesa prerade na kvalitetu steriliziranog graška

master's thesis

• Title (english): Effect of characteristics of raw materials and processing on the quality of sterilized peas
• Author: Borka Lončarić
• 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: 2010-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj rada bio je ispitati kakav je utjecaj karakteristika sirovine i procesa prerade na kvalitetu steriliziranog graška. Trima različitima sortama graška (Barle, Karina i Milor) određivana su fizikalno kemijska svojstva (u alkoholu netopljive tvari (ANT), tekstura, boja) nakon sterilizacije. Također, određena su i fizikalno kemijska svojstva naljeva (udio soli (NaCl), pH vrijednost, sadržaj topljive suhe tvari), te su sve tri sorte senzorski ocijenjene (tekstura, vanjski izgled, boja, miris i okus). Grašak sorti Karina i Milor steriliziran je kao svježa sirovina, dok je grašak sorte Barle steriliziran iz zamrznute sirovine koja je bila skladištena na -18 °C kroz sedam mjeseci. Na sortama graška ispitano je kako različite neto mase punjenja, različite sorte, različite tvrdoće svježe sirovine i različiti režimi sterilizacije utječu na kvalitetu steriliziranog graška i naljeva nakon sterilizacije. Ispitano je kakva je kvaliteta steriliziranog graška iz svježe sirovine, te onog koji je bio prethodno zamrznut, skladišten i odmrznut. Boja graška je mjerena kolorimetrom. Tekstura graška mjerena je teksturometrom. Senzorsko ocjenjivanje provedeno je kvantitativno deskriptivnom metodom. Utvrđeno je da grašak veće tenderometrijske vrijednosti ima veći postotak u ANT, a naljev takvog graška ima nešto višu pH vrijednost i udio soli (NaCl) nakon sterilizacije. Produženim trajanjem sterilizacije u grašku pada postotak u ANT, a pH vrijednost naljeva polagano raste. Uzorak veće mase punjenja zrna ima u naljevu manji udio soli (NaCl). Od dva uzorka graška iste polazne tvrdoće mekšu teksturu ima onaj koji je duže vremena podvrgnut sterilizaciji. Grašak steriliziran iz svježe sirovine (sorte Milor i Karina) ima bolja senzorska svojstva od grašaka steriliziranog iz zamrznute sirovine (sorta Barle), dok je tvrdoća graška u oba slučaja zadovoljavajuća.

Abstract (english)

The aim of this study was to examine what effect does the characteristics of raw materials and processing have on the quality of sterilized peas. Physical and chemical properties (in alcohol insoluble substances (AIS), texture, appearance, colour, smell and taste) were determined for three different varieties of peas (Barle, Karina and Milor) after sterilization. Physical and chemical properties of brine (proportion of salt in the solution (NaCl), pH value, as well as soluble solids were determined and sensorial evaluation of all three varieties was made. The varieties Karina and Milor were sterilized as fresh raw materials, while the pea variety Barle was sterilized out of frozen raw material that was stored for seven months at -18° C. The pea varieties Karina and Milor were examined for how different net weights of grain fillings and different tenderometric values of fresh raw materials affect the quality of sterilized peas and the brine after being stored. The variety Barle was examined for different regimes of sterilization affecting the quality of sterilized peas and brine. The colour of peas was measured by a colorimeter. The texture of peas was measured by a texture meter. The sensory evaluation was carried out by using the quantitative descriptive method. It was determined that the peas of bigger tenderometric values have bigger percentage of AIS and the brine of such peas has after the sterilization a slightly bigger pH value and proportion of salt (NaCl). Prolonged duration of sterilization decreases the percentage of AIS and the pH value of the brine increases slowly. The sample of bigger grain fillings has a smaller proportion of salt (NaCl). Of two samples of peas with the same starting hardness the one which was for longer time subjected to sterilization has the softer texture. The peas sterilized out of fresh raw material (varieties Milor and Karina) have better sensor features than the peas sterilized out of frozen raw materials (variety Barle).

• Keywords: grašak; režim sterilizacije; u alkoholu netopljive tvari; tekstura; boja
• Keywords (english): peas; regimes of sterilization; in alcohol insoluble substances; texture; colour
• Language: croatian
• URN:NBN: urn:nbn:hr:159:253132
• 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: 2017-08-28 11:30:34