Sour Cherry Pomace Valorization as a Bakery Fruit Filling: Chemical Composition, Bioactivity, Quality and Sensory Properties

Sour cherry pomace filling (SCPF) and commercial sour cherry filling (CSCF) produced on a semi-industrial scale were tested and compared in terms of food safety, chemical composition, bioactivity, quality, sensory properties and thermal stability. Both samples were safe for human consumption, thermally stable and there was a lack of syneresis. SCPF had a significantly higher fiber concentration (3.79 g/100 g) due to higher skin fraction and is considered a "source of fibers". The higher skin fraction in SCPF also resulted in a higher mineral quantity (Fe-3.83 mg/kg fw) in comparison to CSCF (Fe-2.87 mg/kg fw). Anthocyanins concentration was lower in SCPF (7.58 mg CGE/100 g fw), suggesting that a significant amount of anthocyanins was removed from SC skin during juice extraction. However, there was a lack of statistical differences in antioxidant activity between the two fillings. CSCF was more spreadable, not as firm and less sticky, with lower storage and loss modulus values than SCPF. However, both fillings exhibited acceptable rheological and textural behaviour for fruit fillings. According to the consumer pastry test, 28 participants preferred each pastry; thus, there was a lack of preference toward any of the tested samples. SCP could be used as a raw material for the bakery fruit fillings industry, which leads to the valorization of food industry by-products.

Comparative characterization of sugar beet fibers to sugar beet pectin and octenyl succinic anhydride modified maltodextrin in aqueous solutions using viscometry, conductometry, tensiometry and component analysis

BACKGROUND

Knowledge about specific functional characteristics, such as viscosimetric, conductometric, tensiometric and structural properties of polysaccharide aqueous solutions is highly important in the successful and adequate application in food emulsion formulation. For the first time detailed characterization of sugar beet fibers aqueous solutions in comparison to high molecular weight (sugar beet pectin) and low molecular weight [octenyl succinic anhydride (OSA) maltodextrin] hydrocolloids/stabilizers was performed through viscometry, conductometry, tensiometry and component analysis.

RESULTS

Sugar beet fibers and its water-soluble fraction were investigated. All sugar beet fiber samples showed substantial surface-active properties but different effect on the viscosity values of aqueous solutions. Sugar beet pectin had higher impact on aqueous solutions viscosity values compared to sugar beet fiber samples. Structural bonding between investigated polysaccharides were evaluated through conductometric measurements. Intermolecular linking and probable embedding of OSA maltodextrin molecules into the sugar beet fiber complex structure was detected in conductometric studies. The increased concentration of sugar beet fibers in the presence of sugar beet pectin led to the accelerated increase in specific conductivity values indicating effects of 'macromolecular crowding', intermolecular and intramolecular conformation changes and charge formation.

CONCLUSIONS

Detailed characterization of sugar beet fibers provided scientific insight towards fundamental characteristics of sugar beet fiber aqueous solutions. The presented characteristics are particularly applicable in the field of food emulsion stabilization due to the presented surface-active properties of sugar beet fibers as well as specific characteristics of investigated multi-polysaccharide systems. © 2022 Society of Chemical Industry.

Ancient Wheat Varieties and Sourdough Fermentation as a Tool to Increase Bioaccessibility of Phenolics and Antioxidant Capacity of Bread

This study aimed to determine the impact of ancient wheat varieties (emmer, spelt and khorasan) and spontaneous sourdough fermentation on the bioaccessibility of total phenolic content (TPC) and the DPPH antioxidant capacity evolution during breadmaking and in vitro digestion. Sourdough and yeast-fermented modern wheat breads were used as controls. After 6 h of fermentation, the total titrable acidity of the sourdough increased from 139 to 167%. The wheat variety, type of fermentation and processing affected TPC, antioxidant activity and bioaccessibility. Antioxidant activity and TPC were reduced by dough mixing, increased after sourdough fermentation and slightly decreased or remained the same after baking. Although wheat flour had the highest TPC, the modeling of TPC kinetic revealed that emmer and spelt sourdough exhibited a higher bound phenolics release rate due to the higher acidity, which contributed to increased phenolics solubility. Although wheat bread, both before and after digestion, had the lowest TPC, especially the one prepared with yeast, high TPC bioaccessibilities and antioxidant activities after the digestion suggested that, except phenolics, digestion process improved the release of additional compounds with different bioaccessibility and biological activity. The results of this study proved that the application of sourdough fermentation can increase the potential of ancient wheats in the developing of functional bakery products.

Techno-Functional Performance of Emmer, Spelt and Khorasan in Spontaneously Fermented Sourdough Bread

The aim of this study was to test the suitability of three different ancient wheat varieties (emmer, spelt and khorasan) to produce spontaneously fermented sourdough bread and to evaluate the impact on the dough rheological properties, ultrastructure and baking quality. Modern wheat sourdough bread and bakery yeast fermented bread were used as controls. Sourdoughs produced from modern and ancient wheats exerted different effects on dough viscoelastic properties, bread specific volume, texture, firming rate, colour and sensory properties, while there was no influence on bread water activity. Both khorasan sourdough, being characterised with the highest dough strength and dense gluten protein matrix, and emmer sourdough, with loose and thin gluten strands of low strength, yielded breads characterised by low specific volume and hard crumb texture. Spelt and modern wheat sourdough were characterised by foam-like dough structures with entrapped gas cells leading to breads of similar specific volume and texture. Although the yeast-fermented wheat flour exerted a higher specific volume and the lowest firmness, the sourdough wheat flour bread had a lower firming rate. A comparison of sourdough bread prepared with modern and ancient wheats revealed that breads based on ancient varieties possess a less noticeable sour taste, odour and flavour, thus contributing to more sensory-appealing sourdough bread.

Impact of Short-Time Micronization on Structural and Thermal Properties of Sugar Beet Fibre and Inulin

Research background

By tailoring dietary fibre's structural and physicochemical properties, their functionality and applicability can be remarkably increased. One of the approaches used in this respect is fibre particle size reduction. Accordingly, the present study explores the impact of short-time micronization in a planetary ball mill on structural and thermal changes of modified and commercial sugar beet fibre, inulin and sucrose for their potential application as food excipients.

Experimental approach

Short-time micronization in a planetary ball mill (30 and 60 min) was applied for particle size reduction of modified and commercial sugar beet fibre, inulin and sucrose as less energy-consumptive and less destructive approach than long-time micronization. Dietary fibre and sucrose samples were characterised in terms of particle size, morphology, intermolecular bonds and presence of functional groups, crystallinity and thermal properties, before and after the short-time micronization.

Results and conclusions

Particle size was successfully reduced to micron-scale already after 30 min of micronization in most of the samples without significant changes in thermal properties and crystallinity or present functional groups. An enhanced particle size decrease with prolonged micronization time (60 min) was noticed in modified sugar beet fibre with slightly wider particle size distribution than in other examined samples. Furthermore, morphology and exposure of the present functional groups in samples were altered by the micronization, which is favourable for their further application as excipients in the food matrix.

Novelty and scientific contribution

The corresponding research reports the short-time micronization impact on sugar beet fibre and modified sugar beet fibre, inulin and sucrose for the first time, hence contributing to the widening of their application as excipients in diverse products.

Gluten-Free Crackers Based on Chickpea and Pumpkin Seed Press Cake Flour: Nutritional, Functional and Sensory Properties

Research background

Despite the growing trend of the gluten-free market and the presence of a wide range of gluten-free products, there are still some shortcomings in nutritional and sensory quality of these products. The commercially available gluten-free products are characterised as products of inferior nutritional quality, particularly in terms of protein and dietary fibre content and with high glycaemic index. On the other hand, from a sensory point of view, gluten-free products usually have inappropriate textural and mechanical properties, poor mouthfeel and flavour. This is a consequence of the limiting choice of raw materials that mainly possess large amount of carbohydrate components.

Experimental approach

Chickpea flour and two types of pumpkin seed press cake flour (virgin and cold pressed), at two substitution mass fractions (20 and 35%), were blended to produce gluten-free crackers without the presence of conventional gluten-free starch-rich ingredients. This study aims to investigate the effect of these non-conventional flours on nutritional and physicochemical properties, sensory acceptability, antioxidant activity and glycaemic index of crackers.

Results and conclusions

All produced crackers can bear nutritional claims 'high fibre', 'source of protein' and 'source of minerals'. Replacing chickpea flour with pumpkin seed press cake flour increased protein and total phenolic content and enhanced antioxidant activity. The selected combination of raw materials allows the production of gluten-free crackers with a moderate glycaemic index. Besides nutrient content, the addition of cold-pressed flour increased overall sensory acceptability, noticeably improving taste and flavour scores compared to the control and crackers with virgin pumpkin seed flour.

Novelty and scientific contribution

To the best of our knowledge, there is no study investigating the use of chickpea and pumpkin seed press cake flour blend without using conventional gluten-free flour and starch. The used non-conventional flour represents complementary raw materials in terms of protein quality and valuable alternatives to produce nutrient-rich, health-promoting gluten-free crackers with reduced glycaemic response and acceptable sensory properties.

Cocoa Spread with Grape Seed Oil and Encapsulated Grape Seed Extract: Impact on Physical Properties, Sensory Characteristics and Polyphenol Content

The aim of this study was to utilize grape pomace, as a polyphenol-rich by-product of wine production, in the manufacture of enriched cocoa spread. The formulation of the cocoa spread has been modified by substitution of refined sunflower oil with cold-pressed grape seed oil. The spread with grape seed oil (Cg) was further enriched with grape seed extract encapsulated on maltodextrins (E), where 10% and 15% of E was added to Cg obtaining the samples Cg10 and Cg15. The results showed an increase in volume-weighted mean in spread samples, from 19.17 μm in Cg to 19.71 μm in Cg10 and 21.04 μm in Cg15. Casson yield stress and Casson viscosity significantly (p ˂ 0.05) increased from 16.41 Pa and 1.58 Pa·s in Cg to 29.45 Pa and 5.70 Pa·s in Cg15 due to the reduction of the fat-phase content in enriched spreads. The addition of E had no significant effect on the melting temperature (Tpeak) of the enriched spreads, while increasing the amount of E significantly (p ˂ 0.05) increased their hardness. The incorporation of grape seed oil in the cocoa spread formulation contributed to an increase in total polyphenols and flavonoids. Moreover, the addition of 10% and 15% of E to Cg resulted in approximately 1.5× and 2× higher content of phenolic compounds in Cg10 and Cg15 compared to control spread with sunflower oil (Cs). Flavonoids increased from 0.43 mg CE/g in Cs to 0.74 mg CE/g in Cg 10 and 1.24 mg CE/g in Cg15. Encapsulates positively affected sensory characteristics of enriched spread samples by reducing their grape seed oil aroma and sweetness.

Effect of Sourdough and Whey Protein Addition on the Technological and Nutritive Characteristics of Sponge Cake

Whey protein and sourdough ferment were used in different combinations to prepare functional sponge cakes, and their mutual influence on batter rheological behaviour as well as product physico–chemical, textural, colour and sensory properties were evaluated. All samples containing whey protein concentrate could bear the nutrition claim ‘a source of protein’. The substitution of wheat flour with whey protein significantly influenced batter viscoelastic behaviour, lowered cake-specific volume, increased product hardness, chewiness, gumminess, and browning index and modified its sensory characteristics. The incorporation of sourdough in protein-enriched sponge cakes improved product-specific volume and appearance compared to a protein-containing sample without sourdough. Although sourdough addition has less of a deteriorating effect on sponge cake rheological and textural properties, when combined with whey protein, it led to a significant reduction in batter elasticity and an increase in product hardness. It was also shown that spontaneously fermented sourdough cannot act as the only leavening agent in sponge cake production. In general, the results of this study have shown that sourdough addition can contribute to improvement in protein-enriched sponge cake quality and that further investigations are necessary in terms of different sourdough and flour type incorporation to minimize the negative effects of protein addition.

Utilization of Sugar Beet Pulp as Biosorbent for Molassigenic Metal Ions: Kinetic Study of Batch Biosorption

The sugar industry is facing problems with high amount of molassigenic metal ions remained after the purification step in sugar juice. In this investigation the application of unmodified sugar beet pulp as a weak monofunctional cation-exchange biosorbent for molassigenic metal ions (Na+, K+ and Ca2+) removal from the alkalized sugar juice was studied. The batch biosorption experiments were performed at temperature (70 °C) and pH (10.5) of alkalized sugar juice similar to industrial conditions. The highest removal efficiency was noticed for divalent Ca2+ (30.2%), while monovalent Na+ and K+ ions were removed with 10.9 and 9.1% efficiency, respectively. Biosorption equilibrium was established in 90 min for all tested metals. Sugar beet pulp characterization from the perspective of cation-exhange material was conducted. The structure of the biosorbent and an insight of the functional groups were also characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The biosorption data were analyzed using four non-linear kinetic (pseudo-first order, pseudo-second order and Elovich) and diffusion models (Weber-Morris). The time course data of biosorption processes fitted well to the pseudo-first and the pseudo-second-order kinetic models indicating ion-exchange and chemisorption as dominant mechanisms for metal ions removal from the alkalized juice. HNO3 as a desorption reagent showed the highest average molassigenic metal ions desorption efficiency (54.4%). Utilization of sugar beet biomass as cation-exchange material imposes as a potential solution for more successful sugar juice purification.

White Chocolate with Resistant Starch: Impact on Physical Properties, Dietary Fiber Content and Sensory Characteristics

Resistant starch (RS) is a part of insoluble dietary fiber, and it could be recognized as a functional food ingredient in some types of confectionery products that lack dietary fiber. Unlike dark and milk chocolate, white chocolate does not contain fat-free cocoa solids rich in dietary fiber. In the present study, 5%, 10%, and 15% of white chocolate were substituted with RS in order to improve the nutritional value of enriched white chocolate. The influence of RS on rheological, textural, and thermal properties of the chocolate fat phase was firstly investigated, and then further influence on physical properties, dietary fiber content, and sensory characteristics of enriched white chocolates were investigated. The obtained results showed that enriched chocolates had increased content of total dietary fiber and reduced total fats and protein content in accordance with the added amount of RS. At the same time, RS increased viscosity and reduced the hardness and volume mean diameter in enriched chocolates in accordance with the added amount. RS improved the nutritional composition of white chocolate by increasing the content of dietary fiber. At the same time, RS did not impair the color and sensory characteristics of enriched white chocolates.

ALIGNING NUTRITION KNOWLEDGE AND DIETARY HABITS OF GENERATION Z-IS THERE A ROOM FOR IMPROVEMENT?

The potential association between determinants such as nutrition knowledge and dietary habits with obesity development among adolescents of generation Z (Zoomers) was investigated in the presented study. Data regarding meals consumption frequency, snack choice and familiarity with amounts of basic food nutrients in diet were gathered throughout a self-designed questionnaire from 854 adolescents (11‒18 years) attending elementary and secondary schools in the Autonomous Province of Vojvodina, Serbia. The corresponding data was analysed and discussed primarily concerning BMI-for-age, and subsequently, gender and educational stage. The association between BMI categories and examined determinants was tested using chi-square and multinomial logistic regression statistics. Although most of the surveyed adolescents had normal weight (72.1%), a notable share of overweight adolescents was also detected (17.9%). Additionally, observed irregularities in breakfast and dinner consumption frequencies and participants’ modest nutrition knowledge can contribute to further diet deterioration. Statistically significant but weak associations between BMI-for-age and choice of snack, dinner consumption frequency, as well as the frequency of salty snack and fast food consumption, were noted. Furthermore, an increase in nutrition knowledge was inversely associated with obesity prevalence (OR 6.56, 95% CI 1.388‒31.037). As an outcome, the need for improvement regarding studied determinants especially nutrition knowledge is established and represents a task to achieve through health promotion strategies among generation Z.

Aligning nutrition knowledge and dietary habits of generation Z: Is there a room for improvement?

The potential association between determinants such as nutrition knowledge and dietary habits with obesity development among adolescents of generation Z (Zoomers) was investigated in the presented study. Data regarding meals consumption frequency, snack choice and familiarity with amounts of basic food nutrients in diet were gathered throughout a self-designed questionnaire from 854 adolescents (11-18 years) attending elementary and secondary schools in the Autonomous Province of Vojvodina, Serbia. The corresponding data was analysed and discussed primarily concerning BMI-forage , and subsequently, gender and educational stage. The association between BMI categories and examined determinants was tested using chi-square and multinomial logistic regression statistics. Although most of the surveyed adolescents had normal weight (72.1%), a notable share of overweight adolescents was also detected (17.9%). Additionally, observed irregularities in breakfast and dinner consumption frequencies and participants' modest nutrition knowledge can contribute to further diet deterioration. Statistically significant but weak associations between BMI-forage and choice of snack, dinner consumption frequency, as well as the frequency of salty snack and fast food consumption, were noted. Furthermore, an increase in nutrition knowledge was inversely associated with obesity prevalence (OR 6.56, 95% CI 1.388-31.037). As an outcome, the need for improvement regarding studied determinants especially nutrition knowledge is established and represents a task to achieve through health promotion strategies among generation Z.

Data-driven Modelling of Microfiltration Process with Embedded Static Mixer for Steepwater from Corn Starch Industry

Cross-flow microfiltration using ceramic tubular membrane was applied for treatment of steepwater from corn starch industry. Experiments are conducted according to the faced centered central composite design at three different transmembrane pressures (1, 2 and 3 bar) and cross-flow velocities (100, 150 and 200 L/h) with and without the usage of Kenics static mixer. For examination of the influence of the selected operating conditions at which usage of the static mixer is justified, a response surface methodology and desirability function approach were used. Obtained results showed improvement in the average permeate flux by using Kenics static mixer for 211 % to 269 % depending on experimental conditions when compared to the system without the static mixer. As a result of optimization, the best results considering flux improvement as well as reduction of specific energy consumption were obtained at low transmembrane pressure and lower feed cross-flow rates.