Improvement of coffee beverage quality by selecting optimal roasting conditions and optimal ratio of different coffee species

Na našim prostorima napitak crne kafe veoma je cijenjen i ima dugu tradiciju pripreme i konzumiranja. Izborom optimalnih parametara procesa prženja u industrijskim uslovima proizvodnje i definisanjem recepture, nastoji se postići odgovarajući kvaliteta, odnosno najprihvatljivija senzorska svojstava napitka kafe. Da bi kafa na određenom tržištu zadovoljila želje i očekivanja porošača, potrebno je definisati parametre kvaliteta kafe za potrebe svakog ciljnog tržišta. Primjenom deskriptivne senzorske analize moguće je dati precizan opis arome, ukusa i boje napitka kafe, kao najvažnijih senzorskih svojstava, sa značajnim uticajem na kvalitet i prihvatljivost kvaliteta. Cilj ove doktorske disertacije je postizanje optimalnog senzorskog kvaliteta napitka crne kafe definisanjem parametara procesa prženja kafe u industrijskim uslovim proizvodnje i definisanjem optimalnog odnosa kafe vrste Arabika i kafe vrste Robuste, kao i definisanje senzorskog profila i sistema senzorskog ocjenjivanja napitka crne kafe koji se priprema na tradicionalan način. Da bi se definisali parametri procesa prženja, neophodno je odrediti optimalnu temperaturu prženja, koja će omogućiti razvoj i formiranje prijatnih senzorskih svojstava u zrnu kafe. Za pripremanje napitka crne kafe na tradicionalan način obično se koriste dvije vrste kafe, Arabika i Robusta u različitom odnosu. Na osnovu rezultata dobijenih hemijsko-fizičkim analizama uzoraka različitih vrsta kafa i mješavina na različitim temperaturama prženja i senzorskom analizom napitka kafe pripremljenog od ispitivanih uzoraka kafe na tradicionalan način, sa ciljem poboljšanja kvaliteta napitka kafe izborom optimalnih uslova prženja i odnosa različitih vrsta kafe može se zaključiti da uzorci napitka kafe pripremljeni od uzoraka proizvedenih prema proizvođačkoj specifikaciji nemaju očekivani kvalitet napitka kafe, kao i da proizvodnjom uzoraka pojedinačnih vrsta kafe pržene na 167°C i 175°C i njihovih mješavina nije postignut optimalni kvaliteta napitka kafe. Takođe je zaključeno da je uzorak napitka kafe pržene na 171°C N1 ocjenjen kao uzorak najboljih senzorskih svojstava (82,35%). Odnos kafa Arabika II klasa, Arabika I klasa i Robusta je bio 34,28%:51,42%:14,30%. Vrijednost titracione kiselosti iznosila je 128,86, sadržaj hlorogenske kiseline 3,77%, sadržaj kofeina 2,29%, sadržaj proteina 13,79%, sadržaj slobodne masti 14,37%, odnosno sadržaj ukupno zasićenih masnih kiselina 42,65%, a sadržaj ukupno nezasićenih masnih kiselina 57,36%, vrijednost pH 5,35 i aktivnost vode 0,102. Antioksidativna aktivnost je iznosila 235,57 μmola TE/g uzorka (DPPH) i 217,62 μmola TE/g uzorka (ABTS). Uzorak U1 napitka kafe pripremljen na tradicionalan način od mješavine kafe pržene na 171°C, sitno mljevene okarakterisan je kao veoma prijatan za konzumiranje, sa najskladnijim aromatskim profilom, usaglašene gorčine i kiselosti, prijatne i umjerene punoće ukusa i blagog i harmoničnog utiska u ustima. Odnos kafa Arabika II klasa, Arabika I klasa i Robusta u ovom uzorku je bio 34,28%:51,42%:14,30%.Consumption of black coffee prepared in a traditional way is very popular in our region. By selecting the optimum parameters of roasting in industrial conditions and defining ratio of the individual species of coffee, it aims to achieve the appropriate quality, and the most acceptable sensory properties of a coffee beverage. In order to fulfill consumers expectations, it is necessary to define the parameters of quality coffee for the needs of each target market. Using descriptive sensory analysis it is possible to give a precise description of the aroma, taste and color of coffee beverage, as the most important sensory characteristics, with significant impact on the quality and acceptability of quality. The aim of this PhD thesis was to achieve optimal sensory quality black coffee beverage, by defining the parameters of the coffee roasting within the industrial conditions and defining the optimal ratio of coffee Arabica and Robusta species, as well as defining a sensory profile and the system of sensory analysis black coffee beverage which was prepared on traditional way. In order to define the parameters of the roasting process, it is necessary to determine the optimum temperature of roasting, which will enable the development and formation of pleasant sensory properties of coffee beans. For the preparation of coffee beverage in the traditional way, usually used two species of coffee, Arabica and Robusta in different ratio. Based on the results of chemical and physical analysis of coffee samples (different species and blends) at different roasting temperatures and results of sensory analysis of a coffee beverage prepared from coffee samples in the traditional way, with the aim of improving the coffee beverage quality, by determining optimal conditions of roasting and ratio of different species of coffee, it could be concluded that the samples of coffee beverage prepared from samples produced according to the production specification do not had the expected quality of coffee beverage. It also could be concluded that by production of individual species of coffee samples roasted at 167 and 175° C, and their blends was not reached optimal quality of coffee beverage. It was also concluded that the coffee beverage of sample roasted at 171C, N1 was rated as the sample of the best sensory properties (82.35%). The ratio of coffee Arabica Class II, Arabica Class I and Robusta was 34.28%: 51.42%: 14.30%. Value of titratable acidity was 128.86, chlorogenic acid content was 3.77%, caffeine content was 2.29%, protein content was 13.79%, the content of free fat was 14.37%, total content of saturated fatty acids was 42.65%, and total content of unsaturated fatty acids was 57.36%, pH value was 5.35 and aw value was 0.102. The antioxidant activity was amounted 235.57 μmol TE/g sample (DPPH) and 217.62 μmol TE/g sample (ABTS). Coffee beverage prepared in the traditional way from a sample U1 roasted at 171 °C, finely ground, was characterized as very pleasant, with the most harmonious aromatic profile, pleasant bitterness and acidity, pleasant and moderate body and gentle and harmonious impression in the mouth. The ratio of coffee Arabica Class II, Arabica Class I and Robusta in this sample was 34.28%: 51.42%: 14.30%

Sweet bakery products for diabetic’s diet and analysis of risk associated with selected ingredients

Diabetes is a complex, chronic illness that demands a healthy diet. The overall quality of consumed food is important for diabetics, but benefits are expected from whole grains and lower-energy food. Choice of appropriate sweet bakery product may present the problem for diabetics in meal planning. The aim of this research is to provide an overview of some opportunities for new food product development for persons with diabetes and to analyze the risks associated with selected food ingredients, which can be used. It includes identification of special requirements for controlled nutrition. Quality parameters and food product composition are determined on a formulation for muffins modified to contain ingredients recommended and safe for diabetics’ diet with lower energy value, but keeping prescribed and acceptable product quality. The research focuses on assessment of the risks analysis associated with selected ingredients on an example of muffin-like cake formulation modelling and use of wheat flour, sugars, fats, salt and some additional ingredients, milk, eggs and cocoa powder, based on experience, insight into recommendations for diabetics’ nutrition and scientifically identified indicators aimed at health protection. Methodology for the selection of the ingredients for energy-reduced muffin-like cakes with whole-grain wheat flour and cocoa, suitable for diabetics’ diet presented in the paper, can be used as a model for developing other products aimed to improve nutrition of persons with healthy food preferences or diseases. In addition, it presents an opportunity for the food industry contribution to healthy lifestyle by developing products adapted to modern dietary recommendations and target consumers group

Nutritive and sensory quality of commercial dry - fermented sausages - ”ČAJNA” type with different salt content

The aim of this study was to evaluate the quality of dry-fermented pork sausages – “čajna” type from the market, with similar composition and different salt content. Physicochemical parameters of selected samples were determined and sensory quality parameters were evaluated. In samples M and D, with significantly higher (P ≤ 0.05) sodium chloride content, higher values of color parameter a* and breaking force and lower values of pH and water activity were found compared to samples T and L. Sample D had the highest protein (25.51%) and sodium chloride content (5.04%), and the lowest fat content (30.04%). Samples M and D had significantly higher sensory quality, especially odor, aroma, taste, consistency and cross-section, compared to other samples. These samples were evaluated as sausages with a pronounced pleasant aroma, taste and odor characteristic for dry-fermented products, with pleasant salinity, appropriate for the product. Although the dry-fermented sausage samples with a lower salt content had more acceptable nutritive values, their sensory quality was lower than expected

Influence of coffee blends and roasting process on the antioxidant activity of coffee

The aim of this paper is to develop specification for the production of roasted coffee with improved nutritional quality. In this sense, the influence of different coffee blends and temperatures of roasting on the antioxidant activity of coffee was examined. Also, the composition of some bioactive components in the analyzed samples was determined. Two Arabica coffees of different quality and Robusta coffee were used for preparation of coffee blends. Experimentally determined green coffee blends B1, B2 and B3 were roasted at 167°C, 171°C and 175°C for 25 minutes in order to establish the effect of temperature roasting on the antioxidant activity and the content of bioactive components in blends. Based on results of DPPH and ABTS test, coffee blends B3 and B2, roasted at 171°C, had the highest (P<0.05) antioxidant activity. Those coffee blends had higher content of Robusta coffee than coffee blend B1. Results of this research can provide opportunities for development roasted ground coffee with improved nutritive quality, which could ensure competitiveness of producers in the target market. Keywords: coffee blends, antioxidant activity, nutritive qualit

EFFECT OF FORMULATION VARIABLES ON SENSORY QUALITY OF THERMO-REVERSIBLE FRUIT FILLING FOR FROZEN SEMI-FINISHED BAKERY PRODUCTS: MODELLING AND OPTIMIZATION

Development of a food product requires integrated scientific and professional knowledge on the technological process, the final product and, the quality of the ingredients and their interaction. This research examined the effect of formulation variables on the sensory quality of a thermo-reversible sour cherry fruit filling, as well as the modelling and optimization of the variables for achieving the quality suitable for filling frozen semi-finished bakery products in industrial conditions. Each formulation for 15 model-samples was successively corrected, to achieve the appropriate sensory quality of the filling in finished products after baking. Their quality was evaluated by descriptive sensory and physico-chemical methods of analysis and compared. The basic formulation for the filling was defined after the successive production of 7 model-samples in laboratory conditions, their use in industrial conditions (puff pastry filling, shaping, quick freezing, storage for at least 24 hours at -18°C, baking and cooling to room temperature) and analysing their quality. Further formulation optimization included selecting: the type and amount of fruits (sour cherry, apple), food additives and cherry flavour for 8 new model-samples. The formulation and ingredients for the fruit filling production (30% sour cherry fruit, 30% apple puree, 58% sugar, 2% starch, 1% pectin, 0.03% firming agent E509, 0.03% acidity regulator E331, 0.025% cherry flavour) and quality parameters (dry matter 65%, acidity 0.85%, pH = 3.2-3.4) were defined. The fruit filling had appropriate sensory quality before and after baking of filled puff pastry: clear cherry-red colour, moderately firm consistency and stable volume, rich fruity aroma, and refreshing sweet-sour taste. The results also confirmed that the product was suitable for manual or machine filling of raw dough

Application of sensory analysis in the assessment of the quality of meat products with different sodium chloride content

The aim of this paper was to evaluate sensory quality of commercial boiled chicken sausages and boiled pork sausages with different salt content. Descriptive sensory analysis was used. The basic physicochemical parameters of samples were also determined. The results showed that the chicken sausage sample with 3.42% salt and the pork sausage sample with 3.03% salt had better sensory quality compared to the samples with 2.43 and 3.30% salt, respectively. Chicken sausages with lower salt content had a less pronounced odour, aroma, taste, and softer consistency with significant differences (P 0.05)

Improvement of coffee beverage quality by selecting optimal roasting conditions and optimal ratio of different coffee species

Na našim prostorima napitak crne kafe veoma je cijenjen i ima dugu tradiciju pripreme i konzumiranja. Izborom optimalnih parametara procesa prženja u industrijskim uslovima proizvodnje i definisanjem recepture, nastoji se postići odgovarajući kvaliteta, odnosno najprihvatljivija senzorska svojstava napitka kafe. Da bi kafa na određenom tržištu zadovoljila želje i očekivanja porošača, potrebno je definisati parametre kvaliteta kafe za potrebe svakog ciljnog tržišta. Primjenom deskriptivne senzorske analize moguće je dati precizan opis arome, ukusa i boje napitka kafe, kao najvažnijih senzorskih svojstava, sa značajnim uticajem na kvalitet i prihvatljivost kvaliteta. Cilj ove doktorske disertacije je postizanje optimalnog senzorskog kvaliteta napitka crne kafe definisanjem parametara procesa prženja kafe u industrijskim uslovim proizvodnje i definisanjem optimalnog odnosa kafe vrste Arabika i kafe vrste Robuste, kao i definisanje senzorskog profila i sistema senzorskog ocjenjivanja napitka crne kafe koji se priprema na tradicionalan način. Da bi se definisali parametri procesa prženja, neophodno je odrediti optimalnu temperaturu prženja, koja će omogućiti razvoj i formiranje prijatnih senzorskih svojstava u zrnu kafe. Za pripremanje napitka crne kafe na tradicionalan način obično se koriste dvije vrste kafe, Arabika i Robusta u različitom odnosu. Na osnovu rezultata dobijenih hemijsko-fizičkim analizama uzoraka različitih vrsta kafa i mješavina na različitim temperaturama prženja i senzorskom analizom napitka kafe pripremljenog od ispitivanih uzoraka kafe na tradicionalan način, sa ciljem poboljšanja kvaliteta napitka kafe izborom optimalnih uslova prženja i odnosa različitih vrsta kafe može se zaključiti da uzorci napitka kafe pripremljeni od uzoraka proizvedenih prema proizvođačkoj specifikaciji nemaju očekivani kvalitet napitka kafe, kao i da proizvodnjom uzoraka pojedinačnih vrsta kafe pržene na 167°C i 175°C i njihovih mješavina nije postignut optimalni kvaliteta napitka kafe. Takođe je zaključeno da je uzorak napitka kafe pržene na 171°C N1 ocjenjen kao uzorak najboljih senzorskih svojstava (82,35%). Odnos kafa Arabika II klasa, Arabika I klasa i Robusta je bio 34,28%:51,42%:14,30%. Vrijednost titracione kiselosti iznosila je 128,86, sadržaj hlorogenske kiseline 3,77%, sadržaj kofeina 2,29%, sadržaj proteina 13,79%, sadržaj slobodne masti 14,37%, odnosno sadržaj ukupno zasićenih masnih kiselina 42,65%, a sadržaj ukupno nezasićenih masnih kiselina 57,36%, vrijednost pH 5,35 i aktivnost vode 0,102. Antioksidativna aktivnost je iznosila 235,57 μmola TE/g uzorka (DPPH) i 217,62 μmola TE/g uzorka (ABTS). Uzorak U1 napitka kafe pripremljen na tradicionalan način od mješavine kafe pržene na 171°C, sitno mljevene okarakterisan je kao veoma prijatan za konzumiranje, sa najskladnijim aromatskim profilom, usaglašene gorčine i kiselosti, prijatne i umjerene punoće ukusa i blagog i harmoničnog utiska u ustima. Odnos kafa Arabika II klasa, Arabika I klasa i Robusta u ovom uzorku je bio 34,28%:51,42%:14,30%.Consumption of black coffee prepared in a traditional way is very popular in our region. By selecting the optimum parameters of roasting in industrial conditions and defining ratio of the individual species of coffee, it aims to achieve the appropriate quality, and the most acceptable sensory properties of a coffee beverage. In order to fulfill consumers expectations, it is necessary to define the parameters of quality coffee for the needs of each target market. Using descriptive sensory analysis it is possible to give a precise description of the aroma, taste and color of coffee beverage, as the most important sensory characteristics, with significant impact on the quality and acceptability of quality. The aim of this PhD thesis was to achieve optimal sensory quality black coffee beverage, by defining the parameters of the coffee roasting within the industrial conditions and defining the optimal ratio of coffee Arabica and Robusta species, as well as defining a sensory profile and the system of sensory analysis black coffee beverage which was prepared on traditional way. In order to define the parameters of the roasting process, it is necessary to determine the optimum temperature of roasting, which will enable the development and formation of pleasant sensory properties of coffee beans. For the preparation of coffee beverage in the traditional way, usually used two species of coffee, Arabica and Robusta in different ratio. Based on the results of chemical and physical analysis of coffee samples (different species and blends) at different roasting temperatures and results of sensory analysis of a coffee beverage prepared from coffee samples in the traditional way, with the aim of improving the coffee beverage quality, by determining optimal conditions of roasting and ratio of different species of coffee, it could be concluded that the samples of coffee beverage prepared from samples produced according to the production specification do not had the expected quality of coffee beverage. It also could be concluded that by production of individual species of coffee samples roasted at 167 and 175° C, and their blends was not reached optimal quality of coffee beverage. It was also concluded that the coffee beverage of sample roasted at 171C, N1 was rated as the sample of the best sensory properties (82.35%). The ratio of coffee Arabica Class II, Arabica Class I and Robusta was 34.28%: 51.42%: 14.30%. Value of titratable acidity was 128.86, chlorogenic acid content was 3.77%, caffeine content was 2.29%, protein content was 13.79%, the content of free fat was 14.37%, total content of saturated fatty acids was 42.65%, and total content of unsaturated fatty acids was 57.36%, pH value was 5.35 and aw value was 0.102. The antioxidant activity was amounted 235.57 μmol TE/g sample (DPPH) and 217.62 μmol TE/g sample (ABTS). Coffee beverage prepared in the traditional way from a sample U1 roasted at 171 °C, finely ground, was characterized as very pleasant, with the most harmonious aromatic profile, pleasant bitterness and acidity, pleasant and moderate body and gentle and harmonious impression in the mouth. The ratio of coffee Arabica Class II, Arabica Class I and Robusta in this sample was 34.28%: 51.42%: 14.30%

Correlations between chemical and certain rheological quality parameters of wheat flour and bread

The aim of this research was to determine existence of the correlation between chemical and certain rheological quality parameters of different wheat flour samples and quality of bread produced from them. Three samples of wheat flour type 500, which were produced as experimental samples in industrial conditions, were analyzed. The analysis of chemical composition (content of water, ash, ash on dry matter, fat, protein, starch) and farinograph parameters (farinograph water absorption, dough development time, stability of dough, softening degree of dough, quality number, quality group) of experimental samples of wheat flour has been conducted. These analyzed flour samples were used for bread production. Also, quality parameters of three produced bread samples were analyzed (volume of bread, mass of bread, overall sensory quality of bread). After that, the existence of the correlation between analyzed parameters has been examined and found as very important correlation between farinograph water absorption (FWA) and parameters of chemical composition: water content (p˂0.05), fat content (p˂0.05), protein content (p˂0.05) and starch content (p˂0.05). Also, a significant impact and positive correlation between the protein content and farinograph water absorption (FWA) on bread volume (p˂0.05) has been found

Influence of Heat Treatment Process on the Acceptability of Pasteurized Beetroot

Abstract: A heat-treated beet is defined as a food that is subject to a temperature, high enough to destroy microorganisms and to preserve all the nutrients. The aim of the study presented in this paper was to investigate the effect by cooking on the properties of heat threated beetroot in the temperature range between 75 °C and 115 °C during the 40, 50 and 60 minutes of cooking. In order to determine the optimal conditions for the implementation of various heat treatment procedures consequently, was followed the influence of heat treatment conditions (temperature/time) on the composition, rheological properties, pH, color change (L*, a*, b*) and sensory characteristics during the development of the “pasteurized/sterilized” beet product. This study has shown that the optimum time and temperature for processing of beetroot is 105 °C at 50 minutes. Samples of beetroot, processed under these conditions had the best softness, the most acceptable taste and color (sensory and instrumentally determined)

Changes of physical properties of coffee beans during roasting

The effects of heating time on physical changes (weight, volume, texture and colour) of coffee beans (Outspan and Guaxupe coffee) were investigated. The roasting temperature of both samples was 170°C and samples for analysis were taken at the intervals of 7 minutes during 40 minutes of roasting. Total weight loss at the end of the roasting process was 14.43 % (light roasted) and 17.15 % (medium to dark roasted) for Outspan and Guaxupe coffee beans, respectively. Significant (P < 0.05) changes in the coffee bean breaking force values were noted between the 7th and 14th minutes, and statistically not significant (P > 0.05) between the 35th and 40th minutes of the roasting. According to the L* colour parameter as a criterion for the classification of roasted coffee colour (light, medium, dark), the Outspan sample was medium and Guaxupe sample was dark roasted