Food Science and Technology International最新文献

The combination of Saccharomyces cerevisiae and Rhizopus oligosporus liquid inoculum has been successfully used to ferment soybeans into tempeh that contains β-glucan. However, using the liquid inoculum of these two microbes as a starter is impractical; so, developing an instant tempeh dry inoculum in powdered form, called the Mosaccha inoculum powder, for ease of use is necessary. This study aimed to determine the best concentration of instant Mosaccha inoculum powder to produce high-quality Mosaccha tempeh. The study used a Complete Randomized Block Design with seven different levels of instant Mosaccha inoculum powder percentage, ranging from 0.3% to 1.8% (w/w). A commercial tempeh inoculum, RAPRIMA, amounting to 0.2%, was used as control. Then, the microbiological (total mold and total yeast) and sensory (color, aroma, texture, and taste) properties were evaluated. The data obtained was analyzed statistically using analysis of variance (ANOVA) and Honestly Significant Difference (HSD) tests at the 5% level. The results showed that the percentage of instant Mosaccha inoculum powder significantly affected the microbiological and sensory properties of Mosaccha tempeh. A concentration of Mosaccha inoculum powder between 0.6% to 1.8% could produce good quality Mosaccha tempeh, but the best Mosaccha tempeh was produced with 1.5% instant Mosaccha inoculum powder, which met the Indonesian National Standards (SNI) 3144:2015, had a very favorable taste, and contained 0.49% β-glucan. Therefore, Mosaccha inoculum in powdered form can be developed and used as a starter in making high-quality tempeh that contains β-glucan.

The investigation was conducted to optimize process variables to manufacture functional pasta from composite flour. The selected grains were steeped, germinated, dried, and milled to produce flour. The flours were mixed at optimized proportions (57.31% buckwheat flour, 12.68% finger millet flour, and 30% paheli dal flour) to produce composite flour. The full factorial experimental design opted for optimization of process variables namely, moisture content (mc) (28, 30, 32, and 34%) and mixing speed (60, 80, 100, and 120 rpm). The optimized multi-grain pasta showed shorter processing time, in-range cooking loss, and higher cooking weight and water absorption capacity (WAC). The highest overall acceptability was recorded for multi-grain pasta processed at 60 rpm with an initial mc of 32%. Proximate analysis of optimized multi-grain pasta showed that pasta contained protein (13.95%), crude fiber (5.05%), ash (2.05%), a lower amount of fat (0.74%), and carbohydrates (71.71%).

The objective of this investigation was to evaluate the influence of two carrier agents, Nopal and Aloe Vera mucilage on the physicochemical properties and stability of blackberry and raspberry powders obtained by spray drying. A pilot scale spray dryer with a feed flow of 20 L/h and an atomization speed of 28,000 rpm was used. The inlet and outlet air temperatures were from 180 to 80 °C, respectively. Yield, moisture content, water activity, hygroscopicity index, solubility time, volumetric density, stability diagrams, micrographs, and particle temperature were evaluated. The highest yields for blackberry extract were 75% with a concentration of 2.5% (w/v) Nopal mucilage, while raspberry extract yielded 65% with a concentration of 5% (w/v) Nopal mucilage. The increase in the concentration of the carrier agent presented an increase in the values of humidity, water activity, volumetric density, and solubility when Nopal mucilage was used as a carrier agent in both blackberry and raspberry extracts. Furthermore, when Aloe Vera mucilage was used as a carrier agent, these same values decreased with increasing concentration. The storage conditions of the powders obtained should be stored at temperatures below 20°C and water activities below 0.4. In addition, the stability diagrams show the particle conditions that should not be exceeded during spray drying.

The aim of this study was to produce chocolate using roasted (RB) and unroasted cocoa beans (URB). The effect of roasting on the total phenolic content (TPC), antioxidant activity [2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) values], phenolic compounds, caffeine, oxidative stability [free fatty acid, peroxide, conjugated dienes, conjugated trienes, and thiobarbituric acid reactive substances (TBARS)], Fourier transform infrared (FTIR), and differential scanning colorimetry (DSC) analysis of both cocoa beans and chocolate samples were analyzed. According to the results, the TPC of URB (24.96 mg gallic acid equivalent (GAE)/g sample) was higher than roasted beans (21.32 mg GAE/g sample). Similar results were also seen in the TPC of chocolate samples. Although roasting did not affect the DPPH scavenging activity and caffeine content of cocoa beans, it decreased FRAP and CUPRAC values. (-)-Epicatechin and chlorogenic acid values were higher in unroasted bean and chocolate samples, but the amount of gallic acid increased with the roasting process. Free fatty acid, peroxide, conjugated dienes, conjugated trienes, and TBARS results of unroasted samples were lower than roasted ones, indicating better oxidative stability. The melting temperatures of cocoa beans changed with roasting while it was similar between chocolate samples. Composition of the beans and the chocolate samples were qualitatively determined with FTIR.

Rice flour (100%, 97.4%, 94.7%, 89.5% (w/w)) and okra powder (2.6%-10.5%) were used to replace wheat flour to make gluten-free chiffon cakes. The effects of okra powder addition on the physicochemical, color, texture, moisture content, total phenolic content, antioxidant, and sensory scores of cakes were evaluated. The batter viscosity, chewiness, ash, protein, fat, total phenolics, and antioxidant activities (1,1-diphenyl-z-picrylhydrazyl hydrate and reducing power) of cakes showed an increasing trend with okra powder addition. Gluten-free chiffon cake containing 5.3% okra powder showed significantly (p < 0.05) higher protein and ash contents as compared to their control and chiffon cake made with wheat flour. Nevertheless, center height, volume index, L*, a*, and b* values, and white index of gluten-free cake decreased with increased okra powder levels. The sensory characteristics of wheat and gluten-free chiffon cakes substituted with 2.6%-5.3% okra powder showed no difference (p > 0.05). Nevertheless, the sensory scores of the 5.3% okra powder addition cake obtained a higher preference than other gluten-free cakes. Although the overall acceptability of gluten-free chiffon cake supplemented with 10.5% okra flour had a lower (p < 0.05) overall acceptability (2.84) than all cake samples, it was still shown acceptable to consumers. Gluten-free rice chiffon cakes with high nutrient contents and antioxidant activities can be processed by the incorporation of okra powder of less than 10.5% to increase the diversification of gluten-free foods. Gluten-free cakes with high amounts of okra powder addition would produce cake having high water content, total phenol content, 1,1-diphenyl-z-picrylhydrazyl hydrate radical scavenging activity, reducing power, hardness, chewiness, cohesiveness, batter viscosity, ash, and crude protein content through principal component analysis.

In baked products, such as muffins, the fat reduction to decrease the caloric content is important without detrimental effects on product quality. Among the fat replacers, emulsion-filled gels imply lower fat depending on the oil fraction. The objective of this work was to replace soybean oil in muffins formulation with two different emulsion-filled gels, containing candelilla wax oleogel or ethylcellulose oleogel as oil fraction, to enhance nutritional quality. Colour, texture, crumb quality, moisture, fat, and protein were analysed. Emulsion-filled gels samples resulted in a darker colour, and a more hard and resilient texture, as a reflection of lower cells number developed in crumbs during baking; but there was a lower fat and an increase in protein content. Emulsion-filled gels with candelilla wax as oil fraction are a alternative to decrease caloric content without compromising the energetic values of the foods.

Sodium metabisulfite is one of the most employed reducing agents in hard biscuit making. The recent results about its adverse effects on human health have pushed us to look in new safer and greener directions. Two different proteases, from distinct strains (bacterial and fungal), were selected and their effects on the dough thermomechanical performances, texture, and structure of the hard biscuits were compared with those obtained from the sodium metabisulfite. Doughs treated with fungal protease showed higher stability during mixing and higher consistency throughout the heating stage. On the other hand, bacterial protease had the greatest weakening effect on protein with a marked reduction of starch gelatinization. Doughs processed with fungal enzymes reached similar values to those containing sodium metabisulfite. In terms of hardness, no significant (p < 0.05) differences were found between biscuits made with bacterial protease and sodium metabisulfite. Analysis of the volumetric characteristics highlighted that bacterial enzymes gave higher values of specific volume and surface area. Regarding the structure of the hard biscuits, sodium metabisulfite produced a more uniform structure with fewer and smaller pockets as compared with the samples treated with proteases.

The aim of this study was to optimize drying conditions during ultrasonic-assisted osmotic dehydration and subsequent microwave drying of red beetroot using the Box-Behnken design. For this purpose, ultrasonic-assisted osmotic dehydration was performed at different ultrasonic powers (50, 75, and 100 W), sonication times (20, 40, and 60 min), and salt concentrations (0%, 15%, and 30%). The subsequent drying procedures were conducted with 231, 518, and 805 W microwave power. The best condition was selected as 5.15% salt concentration, 20 min sonication time, 50 W ultrasonic power, and 716.45 W microwave power. The responses obtained under optimum conditions were determined as 68.06%, 9.54 mg GAE/g dm, 28.23, 42.66, and 3.08 for DPPH• % inhibition, total phenolic content, L*, a*, and b* values, respectively. While favorable impacts on color were detected for the applied pretreatments, the DPPH• scavenging activities of the dried beetroot were determined to be more significant after ultrasonic-assisted osmotic dehydration. Furthermore, the drying kinetics of beetroot were evaluated according to the Midilli et al. model. When the fit to the model was investigated, it was compatible at R²> 0.90 level. As a result, the ultrasonic-assisted osmotic dehydration pretreatment performed before the microwave drying method preserved the quality characteristics of beetroot samples and was successfully applied.

Antioxidants in fruit and vegetable juices have become increasingly popular because of their potential health benefits. Nowadays, juice mixes made from berries present frequent consumer choices, due to their nutritive value and high content of bioactive compounds. Commercial fruit and vegetable juices available in Serbian markets (n = 32) were analyzed for the physicochemical properties, chemical composition, and antioxidant activity. Relative antioxidant capacity index was used for the ranking of the juices according to antioxidant capacity, while antioxidant effectiveness of phenolic compounds contained in juice samples was investigated depending on phenolic antioxidant coefficients. Principal component analysis was applied to study the data structure. In addition, a multi-layer perceptron model was used for modeling an artificial neural network model (ANN) for prediction antioxidant activity (DPPH, reducing power, and ABTS) based on total phenolic, total pigments, and vitamin C content. The obtained ANN showed good prediction capabilities (the r² values during training cycle for output variables were 0.942). Phenolic, pigments, and vitamin C contents showed a positive correlation with the investigated antioxidant activity. The consumption of commercial berry fruit juices available in Serbian markets may deliver great health benefits through the supply of natural antioxidants.

In this study, the effect of dual modification using ultrasound (100 and 300 W for 5, 10, and 15 min) and microwave (600 W for 45 s) treatments on functional properties of wheat gluten protein (WGP) and whey protein concentrate (WPC), as two by-products of food industry with different primary functional properties, was investigated. Ultrasound treatment did not affect the solubility of both proteins significantly but the emulsion and foam properties were increased up to 10 min. Nevertheless, microwave treatment after ultrasound caused a significant decrease in the solubility of both proteins. However, the foam stability of the WPC and WGP was not significantly modified after microwave treatment. The obtained results showed a more positive effect of ultrasound at 100 W for 10 min than other ultrasound treatments on the functional and structural properties of both proteins. The zeta potential of both proteins was decreased after dual physical modifications, but thermal stability of proteins was improved after microwave treatment.