Vpliv dodatkov na kakovost toasta

Bajc, Jernej (author), Bertoncelj, Jasna (mentor), Šegatin, Nataša (co-mentor)

Cilj raziskave je bil ovrednotiti kakovost toasta z različnimi dodatki, kot so glicerol, glukomanan, kalcijev laktat, maltodekstrin in modificirano mleko. Toaste smo pripravili s predhodno pripravljeno mešanico suhih sestavin, mleka, kvasa, palmine masti, vode, kislega testa in izbranega dodatka, ki je bil dodan v 0,5 % in 1 % glede na maso moke, v primeru dodatka glicerola tudi 3 %. Izbrani dodatki so bili uporabljeni v nizkih koncentracijah z namenom, da minimalno vplivajo na senzorične lastnosti toasta. Svežim vzorcem toasta smo prvi dan po peki določili hranilno vrednost (vsebnost beljakovin, maščob, ogljikovih hidratov, prehranske vlaknine in pepela ter energijsko vrednost). Kontrolnemu toastu in toastom z dodatki smo vsake tri dni, do pojava prve plesni, določili izbrane parametre (vodna aktivnost, vrednost pH, vsebnost vode, tekstura in senzorične lastnosti). Pri vseh toastih z dodatki smo, v primerjavi s kontrolnim toastom, vsaj pri enem od analiziranih parametrov opazili razlike. Rezultati senzorične analize kažejo, da imajo dodatki vpliv na senzorične lastnosti toastov, najpogosteje so vplivali na vonj, okus in aromo, dodatek modificiranega mleka je povzročil tudi rumenkasto barvo sredice, pri toastih z dodatkom maltodekstrina pa smo opazili spremenjeno poroznost sredice. Pri vseh vzorcih toasta se je skupna senzorična ocena tekom skladiščenja zmanjšala. Vpliv dodatkov v toastih pri ostalih obravnavanih parametrih ni bil tako izrazit, z nekaj izjemami. Dodatek glicerola je znižal vodno aktivnost, kar je nekoliko podaljšalo čas do pojava plesni. Dodatek kalcijevega laktata je znižal vrednost pH toasta, kar se je negativno izrazilo pri senzorični oceni. Toast z dodatkom glukomanana je v primerjavi s kontrolnim toastom vseboval več vode, zaradi česar je bil mehkejši, vendar tudi podvržen hitrejšemu pojavu plesni. Za dodatek maltodekstrina sklepamo, da je imel na končne lastnosti toastov le posreden vpliv, zaradi izrazitejše fermentacije v teh toastih in posledično bolj grobe poroznosti sredice, ker je bil porabljen kot substrat za kvasovke. Dodatek modificiranega mleka je izboljšal senzorične lastnosti toasta in mehkobo, po 14-ih dneh pa se je pojavila neprijetna rahlo kisla nota. Glede na rezultate lahko zaključimo, da dodatki vplivajo na kakovost toastov, vendar lahko zaradi nizkih koncentracij dodatkov vpliv opazimo le pri medsebojni primerjavi toastov.

• Language: Slovenian
• Keywords: pekovski izdelki, toast, aditivi, pekovski aditivi, glicerol, glukomanan, kalcijev laktat, maltodekstrin, modificirano mleko, hranilna vrednost, kakovost, staranje toasta, senzorične lastnosti, vodna aktivnost, tekstura
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [J. Bajc]
• Year: 2017
• PID: 20.500.12556/RUL-91404
• UDC: 664.664.32:641.1:543.92
• COBISS.SI-ID: 4768376
• Publication date in RUL: 05.04.2017

Secondary language

• Language: English
• Title: The influence of additives on toast bread quality

Abstract

The aim of the study was to evaluate the quality of the toast bread with a variety of additives, such as glycerol, glucomannan, calcium lactate, maltodextrin and modified powder milk. Toast breads were prepared with the prepared mixture of dry ingredients, milk, yeast, palm fat, water, sour dough and one of the selected additives which were added in 0.5% and 1% by weight of flour, in the case of glycerol also 3%. The chosen additives were used in low concentrations in order to minimally affect the sensory properties of the toast. We determined the nutritional value of toast bread samples the first day after baking (contents of protein, fat, carbohydrates, dietary fiber and ash as well as energy value). Selected parameters (water activity, pH value, water content, texture, and sensory properties) were measured every three days, until the occurrence of mold. All of toasts with additives were compared with the control toast. The results of the sensory analysis show that the additives in toast bread have an influence on the sensory properties. They most commonly affected the odor, taste and aroma, modified milk powder also caused a yellowish color of the crumb, in the toast with maltodextrin addition different porosity of the crumb was observed. In all of the samples, the overall sensory score during storage decreased. Effect of additives on toast in the other examined parameters was not as pronounced, with a few exceptions. The addition of glycerol decreased water activity, which slightly prolonged the time for the mold to appear. The addition of calcium lactate reduced the pH value of the toasts, which had a negative effect on the sensory score. Toast with the added glucomannan contained more water in comparison with the control, and was softer, but was also subject to rapid mold growth. We concluded that maltodextrin had only an indirect effect on the observed parameters due to stronger fermentation of the dough, as we observed coarser porosity in the toast crumb. The addition of the modified milk powder had improved the sensory properties and the texture of toast bread, but after 14 days, there was a slightly unpleasant sour note. Based on the results we can conclude that the additives affect the quality of toast bread, but due to low concentrations of additives, their influence is observed only in comparison of the toast breads.

• Keywords: bakery products, toast, additives, bakery additives, glycerol, glucomannan, calcium lactate, maltodextrin, modified milk, nutritional value, quality, toast staling, sensory properties, water activity, texture