Optimizacija tehnološkog procesa proizvodnje namaza sa visokim sadržajem omega masnih kiselina upotrebom pogače semena uljane tikve golice

Abstract

Cilj istraţivanja u okviru ove teze je bio da se ispita mogušnost upotrebe pogače uljane tikve golice, nusproizvoda pri proizvodnji devičanskog ulja, za proizvodnju namaza sličnom kikiriki maslacu, kako po spoljašnjem izgledu i teksturi, tako i po reološkoj stabilnosti. Namazi su formulisani tako da imaju visok sadrţaj omega-6 i omega-3 masnih kiselina, uz njihov izbalansirani odnos prema principima kvalitetne ishrane i preporukama nutricionista, prijatna senzorska svojstva i dobru oksidativnu stabilnost. Upotrebom dvo-faktorskog eksperimentalnog dizajna na pet nivoa i metode odzivnih površina, kao i statističke analize podataka, izvršena je optimizacija tehnološkog procesa za proizvodnju namaza sa definisanim poţeljnim funkcionalnim karakteristikama proizvoda sa nutricionističkog i teksturalnog aspekta. Rezultati su pokazali da je pogača (na 100 g proizvoda) veoma bogata mineralima, uz izuzetno visok sadrţaj fosfora, gvoţđa, magnezijuma i cinka koji prevazilazi 100% dnevnih potreba prema Pravilniku (2004), a takođe sadrţi i velike količine mangana, kalijuma i bakra, te opravdava valorizaciju iste za proizvodnju nutritivno visokovrednog namaza. Devičansko tikvino ulje, poreklom iz pogače, je znatno doprinelo i nutritivnoj vrednosti namaza, buduši da je isto bogato omega-6 masnim kiselinama (51.04%) i γ-tokoferolima (704 mg/kg). Konopljino ulje je veoma uticalo na senzornu ocenu namaza, pre svega na ukus i teksturu, kao i na oksidativnu stabilnost. Ustanovljeno je da rok trajanja namaza zavisi od stepena oksidacije ulja u njegovom sastavu, pre svega od količine i kvaliteta konopljinog ulja, i moţe biti najduţe do 6 meseci pri sobnoj temperaturi čuvanja. Utvrđeno je da izdvajanje ulja na površini namaza zavisi od količine dodatog stabilizatora, a najbolji rezultati su postignuti dodatkom 1.6% stabilizatora. Optimalna vrednost za dobijanje namaza najprihvatljivijeg nutritivnog i senzornog kvaliteta, oksidativne stabilnosti i teksture, je sadrţaj stabilizatora od 1.2-1.4% uz 40-60% dodatog konopljinog ulja u masnu fazu proizvoda. Svi proizvedeni namazi su sadrţali esencijalnu omega-3 masnu kiselinu uz mogušnost deklarisanja kao „izvor omega-3 polinezasišenih masnih kiselina“, od kojih su pojedini uzorci imali vrlo visok sadrţaj (0.98 i 1.24 g) po konzumnoj jednici (15 g). Svi proizvedeni namazi su sadrţali i omega-6 masne kiseline, od kojih su pojedini uzorci imali visok sadrţaj po konzumnoj jedinici (2.5-3 g), uz mogušnost deklarisanja kao „izvor omega-6 polinezasišenih masnih kiselina“. Svi namazi (izuzev jednog) su imali odlično izbalansiran odnos između omega-6 i omega-3 masnih kiselina (2-3:1).

The goal of this research was to investigate the possible use of hull-less pumpkin seed oil press cake, a by-product of the pumpkin seed oil pressing process, for the manufacturing of a spread. The spread would be similar to a peanut butter, in appearance, texture and rheological stability. Spreads were formulated in such way that they would have pleasant sensory attributes, good oxidative stability with a high omega-6 and omega-3 fatty acids content, while providing their balanced ratio based on modern healthy food principles as recommended by nutritionists. Optimization of the spread manufacturing technology was conducted based on the results of the two factorial experimental design on five levels using response surface methodology and statistical analysis (ANOVA). Desirable functional characteristics of the spreads were defined based on nutritional and textural attributes. Results have shown that pumpkin seed oil press cake (per 100 g) is very rich in minerals, especially phosphorus iron, magnesium and zinc that exceeds recommended daily intake (Pravilnik, 2004) over 100%. In addition, it contains high amounts of manganese, potassium and copper, which justifies the use of the seed oil press cake for investigation of the possibility for its use in nutritious spread manufacturing. Cold pressed hull-less pumpkin oil significantly contributed to the nutritional value of the spreads, since it is rich in omega-6 fatty acids (51.04%) and γ-tocopherols (704 mg/kg). Hemp oil had a significant effect on the sensory evaluation of the spreads, primarily on the taste and texture, as well as the oxidative stability of the spreads. It was confirmed that the shelf life of the spreads depended on the oxidation of the oils present in the spread, and primarily depended on the hemp oil quantity and quality. All spreads had a shelf life of maximum 6 months at ambient temperature. It was also confirmed that oil separation on the spreads’ surface depended on the amount of added stabilizer, where the best results were achieved with the addition of 1.6% stabilizer. Considering nutritional value, sensory evaluation, oxidative stability and texture, the optimal spreads were made using the stabilizer at 1.2-1.4% and hemp oil at 40-60% added to the fatty phaze of the spread. All prepared spreads contained omega-3 essential fatty acid that could be declared as a “source of omega-3 polyunsaturated fatty acids“. Few samples had a very high content of omega-3 fatty acids (0.98 and 1.24 g) per serving size 15 g). In addition, all prepared spreads contained omega-6 fatty acids, where some samples had a high content of omega-6 fatty acids per serving size (2.5-3 g), and could be declared as a “source of omega-6 polyunsaturated fatty acids“. All prepared spreads (except one) had a well balanced ratio between omega-6 and omega-3 fatty acids (2-3:1).