Olive stone powder: A potential source of fiber and antioxidant and its effect on the rheological characteristics of biscuit dough and quality

Lignocellulolytic Enzymes Production by Four Wild Filamentous Fungi for Olive Stones Valorization: Comparing Three Fermentation Regimens

Lignocellulolytic enzymes play a crucial role in efficiently converting lignocellulose into valuable platform molecules in various industries. However, they are limited by their production yields, costs, and stability. Consequently, their production by producers adapted to local environments and the choice of low-cost raw materials can address these limitations. Due to the large amounts of olive stones (OS) generated in Morocco which are still undervalued, Penicillium crustosum, Fusarium nygamai, Trichoderma capillare, and Aspergillus calidoustus, are cultivated under different fermentation techniques using this by-product as a local lignocellulosic substrate. Based on a multilevel factorial design, their potential to produce lignocellulolytic enzymes during 15 days of dark incubation was evaluated. The results revealed that P. crustosum expressed a maximum total cellulase activity of 10.9 IU/ml under sequential fermentation (SF) and 3.6 IU/ml of β-glucosidase activity under submerged fermentation (SmF). F. nygamai recorded the best laccase activity of 9 IU/ml under solid-state fermentation (SSF). Unlike T. capillare, SF was the inducive culture for the former activity with 7.6 IU/ml. A. calidoustus produced, respectively, 1,009 μg/ml of proteins and 11.5 IU/ml of endoglucanase activity as the best results achieved. Optimum cellulase production took place after the 5th day under SF, while ligninases occurred between the 9th and the 11th days under SSF. This study reports for the first time the lignocellulolytic activities of F. nygamai and A. calidoustus. Furthermore, it underlines the potential of the four fungi as biomass decomposers for environmentally-friendly applications, emphasizing the efficiency of OS as an inducing substrate for enzyme production.

Rhubarb powder: Potential uses as a functional bread ingredient

As a traditional staple food, bread lacks several nutrients such as fiber and minerals. In this study, the possibilities of using rhubarb powder to enrich wheat bread were investigated. Rhubarb powder was replaced with wheat flour at the ratios of 0%, 4%, 8%, and 12%. In order to reveal effects of rhubarb powder on quality properties of bread, color, moisture, total protein, fat content, antioxidant activity, textural, and sensory analysis were conducted. As the rhubarb powder ratio increased, the fiber (10.60 ± 0.55), ash (4.34 ± 0.13), and fat content (2.17 ± 0.55) of bread samples increased significantly (p < 0.05). Antioxidant activity (19.61% ± 0.53%) and total phenolic contents (916.38 ± 2.69) of bread samples also increased significantly (p < 0.05). The colors of the enriched breads were relatively dark. The breads containing 12% rhubarb powder had the highest ash content (4.34 ± 0.13). The samples containing 4% rhubarb powder took the highest sensory scores from the sensory panel in terms of odor, flavor, and overall impression. However, as the ratio of rhubarb powder increased, the sensory values of bread samples decreased. According to the results of this study, rhubarb powder could be used up to 4% to produce acceptable breads in terms of sensory properties with improved nutritional quality.

Effects of different types of electrolyzed waters on rheological characteristics of dough and quality properties of bread

Water is an ingredient of considerable importance in bread dough. Effects of four different types of electrolyzed water (Anolyte NaCl, Catholyte NaCl, Anolyte Na2CO3, Catholyte Na2CO3) on quality characteristics of bread were investigated. For this aim, rheological and textural analysis of bread doughs and color, physical properties, water activity, moisture content, antioxidant activity, total phenolic content, texture profile analysis, and micrographic analysis of bread samples were performed. Electrolyzed water affected quality characteristics of dough and bread samples significantly (p < 0.05). Anolyte Na2CO3 increased the water-holding capacity of the dough from 60 ± 0.05 to 66 ± 0.07. The bread samples prepared with Anolyte Na2CO3 (363 ± 1.70) and Catholyte Na2CO3 (346 ± 1.61) electrolyzed water has higher loaf volume than the bread samples prepared with Anolyte NaCl (320 ± 1.00) and Catholyte NaCl (310 ± 1.52) electrolyzed water and control bread (270 ± 1.04) (p < 0.05). Electrolyzed water also increased the antioxidant activity (23.62 ± 0.05% inhibition) and total phenolic content (460.61 ± 2.12 GAE/100 g) of bread samples. The results of this study may be evidence that using electrolyzed water can improve the quality characteristics of bread.

Utilization of industrial hemp by-product defatted seed flour: effect of its incorporation on the properties and quality characteristics of 'tsoureki', a rich-dough baked Greek product

BACKGROUND

A rich-dough baked Greek product named 'tsoureki' was prepared using non-gluten hemp seed flour at ratios of 0:100, 10:90, 30:70, and 50:50. The effects of hemp flour addition on the properties of 'tsoureki', including physicochemical properties (moisture content, water activity, sorption phenomena), structural properties, textural properties, total phenolic content, antioxidant activity, and sensorial characteristics, as well as the macroscopic structure and morphological characteristics, were studied.

RESULTS

Hemp flour addition affected dough rheology, showing tan δ values < 1, a decrease in both G' and G″ values, while both flow behavior and consistency indices were also significantly affected, which might have an influence on the final baked goods. The Guggenheim-Anderson-de Boer model satisfactorily described sorption data, while both hemp addition and temperature had a significant effect. A significantly higher hardness of 11.55 N, a lower specific volume of 2.65 cm³  g^-1 , and a lower porosity of 0.676 were observed at high hemp additions. The hemp flour level influenced the color of the crumb and crust, and the total color difference (ΔE) increased significantly with the increase in hemp flour. Hemp flour additions were detectable by the naked eye, with an obvious color difference between control and hemp-containing samples. Moreover, the phenolic content and antioxidant capacity were increased, as were some organoleptic characteristics, such as the bitter aftertaste. Concurrently, overall acceptability decreased significantly.

CONCLUSION

Overall, the incorporation of gluten-free defatted hemp seed flour in 'tsoureki' formulations seems to be a promising alternative for improving quality of such rich-dough baked products. © 2022 Society of Chemical Industry.

Phenolic Compounds and Antioxidant Status of Cookies Supplemented with Apple Pomace

The post-production leftovers after the pressing of apple juice are a rich source of health-promoting compounds, which could be used in the food industry for the manufacture of dietary foods, applicable also for people with celiac disease. This raw material is currently little used, and the cost of its disposal is considerable. Therefore, an attempt was made to enrich gluten-free cookies with different proportions of apple pomace. The content of individual polyphenols determined by the UPLC-PDA-MS/MS method, basic chemical composition, physical properties of cookies with 15%, 30%, 45%, and 60% apple pomace, were evaluated. It was found that apple pomace in gluten-free cookies caused an increase in the content of phenolic acids, quercetin derivatives, flavan-3-ols and dihydrochalcones. An elevation in protein, fat, and minerals was also observed. The growing share of apple pomace caused a significant increase in the content of total fiber, soluble, and insoluble fractions, but resulted in an increase in the hardness and darkening of the cookies while reducing their volume.

Effect of Wheat Replacement by Pulse Flours on the Texture, Color, and Sensorial Characteristics of Crackers: Flash Profile Analysis

Pulse flours are growing in popularity as alternatives to wheat in bakery products due to their high protein and nutritional value. However, the effect of different pulse species and substitution on sensory perception is unclear. The sensory perception of crackers made by partially replacing wheat with chickpea (40-80%) and lupin flour (10-30%) was evaluated using Flash profile analysis in association with instrumental analysis of texture and color. Flash profile analysis was conducted in Greece and Indonesia in order to allow culture comparison of the profiling of the samples and language by the subjects of the panel. Lightness (L∗) and hardness of crackers were decreased by the addition of pulses. Flash profile analysis indicated an association among color, texture, and sensory perception by judges. Derived attributes were associated with the physicochemical characteristics and raw materials of crackers for both panels. GPA analysis of Greek panel indicated that increasing the replacement of wheat led to the generation of more attributes regardless of pulse species, while the Indonesian panel was able to detect differences among pulse species.

Whole wheat bread enriched with silver fir (Abies alba Mill.) needles extract: technological and antioxidant properties

BACKGROUND

The interest of consumers and market and scientific research for added-value foods obtained with environmentally sustainable productive chains is increasing. Silver fir (Abies alba Mill.) needles (SFNs), often by-products of forest management and logging, represent an unexploited source of bioactive compounds.

RESULTS

For the first time, SFN aqueous extract obtained through controlled hydrodynamic cavitation was used to enrich whole wheat flour bread. The first trial found that 35% SFNs extract addition was the absolute threshold of taste perception. The second trial investigated dough rheological properties and bread technological and antioxidant properties in samples enriched with 35% and 100% SFNs extract compared with the control (0% SFNs extract). SFNs extract significantly increased bread antioxidant capacity in both 35% and 100% SFN fresh breads by ~42.5% and ~87% respectively and in 100% SFNs bread samples after 72 h of storage by ~76%. Enrichment of 35% showed higher alveograph dough extensibility (~11%) and different bread texture in terms of hardness, springiness, and chewiness. Enrichment with 100% SFNs extract significantly improved dough and bread technological quality: it increased alveograph dough extensibility L (~18%), swelling index G (~8%), and flour strength W (~14%) and showed the highest increase in bread specific volume (~0.200 L kg^-1 ).

CONCLUSIONS

SFNs aqueous extract produced with controlled hydrodynamic cavitation appeared a valuable technical material for the manufacturing of added-value and functional breads. © 2021 Society of Chemical Industry.

Designing Nutritious and Sustainable Biscuits Using Upcycled Fibre-Rich Ingredients Obtained by Hot Air - Microwave Drying of Orange by-Products

Circular use of resources implies developing mild processes to transform food by-products into value-added products, without using organic solvents or extensive washing and drying steps. Refined ingredients are commonly used in gluten-free bakery resulting in high levels of saturated fatty acids and sugars as well as a lack of essential nutrients like dietary fibres. The objective of this study was (i) to compare the nutritional composition and the water retention capacity (WRC) of an upcycled orange fibre dried by hot air combined with microwave (HAD+MW) and a commercial orange fibre obtained by different methods (COM), and (ii) to compare the nutritional, texture and sensory profile of gluten-free biscuits formulated with HAD+MW and with COM fibres. The total dietary fibre content (72.0 ± 3.0%) and WRC (21.1 ± 2.7 g_water/ g) of HAD+MW fibre did not differ from the nutritional composition of the control orange fibre (COM). However, for HAD+MW fibre, protein (+2.34 fold), fat (-4.75 fold), ash (-2.31 fold), sugars (-1.42 fold) and moisture content (+11.5 fold) was different from COM. Instrumental texture analysis showed that biscuits with HAD+MW fiber resulted in less hardness (26%) than those with COM fiber. However, this difference was not perceived by panellists (p > 0.05). Exterior colour, cereal, vanilla and citrus aroma-flavour, and granularity were slightly more intense in HAD+MW biscuits but still similar to the commercial control fiber. Thus, the HAD+MW drying method can be used for upcycling orange by-products, obtaining less refined and more nutritious and sustainable ingredients for fiber-enrichment of gluten-free biscuits.

Valorization of microwave roasted Tamarindus indica seed in functional biscuit production and effects on rheological and textural properties of biscuit dough

As one of the most popular bakery products, biscuits lack several nutrients such as fiber, protein, and some minerals. In this study, biscuits were enriched with T. indica seed flour. T. indica seeds were roasted by microwave at 600 W for 8, 16 and 24 min. Wheat flour was substituted by unroasted and roasted tamarind flour at level of 10%. Owing to its appreciated antioxidant activity, fiber and protein content, T. indica seed flour improved the nutritional value and antioxidative properties of biscuits. The fiber content of biscuits increased up to 3.88 ± 0.02% and protein content up to 11.22 ± 0.05 (p < 0.05). Moderately roasting process developed the sensory and antioxidative properties of T. indica seeds. Microwave roasting was used successfully for roasting T. indica seeds.

Incorporation of high fructose corn syrup with different fructose levels into biscuit: An assessment of physicochemical and textural properties

This study examined the effects of different concentrations of high-fructose corn syrup (HFCS, 28%, 44%, 55%) used in biscuit formulation on the hydroxymethyl furfural (HMF) acrylamide content, and textural properties were investigated and compared with invert sugar and sucrose-incorporated samples. No significant difference in the chemical composition (moisture, fat, protein, and ash) among different samples was noted based on the results. The highest L* was associated with a control sample containing sugar and invert sugar, although an increase in F55 content decreased the L* value significantly (p < .05). The highest hardness value was correlated with control samples (6.5 N), although the sample with 12.5% F42 and 25% F55 demonstrated lower hardness 6.27 N, and the lowest hardness value (3.97 N) was related to the sample containing 12.5% F42 and 25% F28. The amounts of water activity of all samples were in the range of 0.22 to 0.29, with the highest amount related to the control sample. The SEM images showed a uniform surface with several holes for all the biscuits. The highest and lowest (HMF) levels were related to the samples containing 25% F55 (46.04) and 12.5% F42 with 2.36 ppm. The control sample with the acrylamide amount of 28.50 ppb and the sample containing 12.5% F42 and 25% F55 with the acrylamide amount of 27.33 ppb showed the highest acrylamide content.

Olive Tree in Circular Economy as a Source of Secondary Metabolites Active for Human and Animal Health Beyond Oxidative Stress and Inflammation

Extra-virgin olive oil (EVOO) contains many bioactive compounds with multiple biological activities that make it one of the most important functional foods. Both the constituents of the lipid fraction and that of the unsaponifiable fraction show a clear action in reducing oxidative stress by acting on various body components, at concentrations established by the European Food Safety Authority's claims. In addition to the main product obtained by the mechanical pressing of the fruit, i.e., the EVOO, the residual by-products of the process also contain significant amounts of antioxidant molecules, thus potentially making the Olea europea L. an excellent example of the circular economy. In fact, the olive mill wastewaters, the leaves, the pomace, and the pits discharged from the EVOO production process are partially recycled in the nutraceutical and cosmeceutical fields also because of their antioxidant effect. This work presents an overview of the biological activities of these by-products, as shown by in vitro and in vivo assays, and also from clinical trials, as well as their main formulations currently available on the market.

Optimization of Ingredients for Biscuits Enriched with Rapeseed Press Cake—Changes in Their Antioxidant and Sensory Properties

The optimum formulation for wheat flour (WF)-based biscuits containing the rapeseed press cake (RPC)—the primary by-product of rapeseed oil production rich in phenolic compounds and different types of fats (rapeseed oil, margarine and coconut oil)—was estimated using the central composite design (CCD) with two factors and response surface methodology (RSM). Effects of partial substitution of WF for RPC (0–40 g) in a total flour blend (100 g) and fats with various amounts of saturated fatty acids (SAFA = 2.3–24.9 g) on antioxidant capacity (AC) and sensory characteristics (color, odor, texture, flavor, overall acceptability, and purchase intent scores) of the novel biscuits were investigated. Conventional solid (liquid)–liquid extraction and ultrasound-assisted extraction (UAE) were applied to extract total antioxidants from main ingredients used for the preparation of doughs as well as the baked biscuits. The AC of biscuits and their components were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The DPPH results were the highest for the RPC flour (DPPH = 15,358–15,630 μmol Trolox (TE)/100 g) and biscuits containing rapeseed oil and 40 g of RPC flour (DPPH = 7395–10,088 μmol TE/100 g). However, these biscuits had lower sensory scores for each attribute and the lowest purchase intent scores. The quadratic response surfaces were drawn from the mathematical models in order to ensure the good quality of the proposed biscuits with RPC. The DPPH results obtained and the mean sensory scores correlate with the predicted values (R2 = 0.7751–0.9969). The addition of RPC with high antioxidant potential to biscuits and the replacement of margarine or coconut oil by rapeseed oil interfered with their acceptability.

Effects of waste fig seed powder on quality as an innovative ingredient in biscuit formulation

Being a rich source of antioxidants, phenolic compounds and dietary fiber, the fig seed could be valuable health-promoting food ingredient. The possibility of using fig seed powder in biscuits was investigated. For this purpose, wheat flour was replaced by fig seed powder at levels of 0, 5, 10, and 15%. The effects of replacement on proximate composition, color values, total phenolic contents, antioxidant activity, textural characteristics, and sensorial properties of biscuit samples were investigated. The composition of fig seed powder showed a significantly higher concentration of fiber (56.6 ± 0.27%), protein (14.32 ± 0.21%), fat (20.32 ± 0.32%), and total phenolic content (665.12 ± 0.52 mg GAE/100 g). The biscuit samples were obtained with increased fiber content by adding fig seed powder to the biscuit formulation. Moreover, fig seed powder increased the total phenolic content and antioxidant activity of biscuits significantly (P < 0.05). The addition of fig seed powder to the biscuit formulation up to 10% increased the sensory scores of the biscuits in terms of odor, flavor, and overall impression. PRACTICAL APPLICATION: The use of waste products in food industry is relevant in terms of the circular economy context. The enrichment of biscuit with waste fig seed powder could also supplies accessional channel for valorization of a food waste. Fig seed powder could be used to produce acceptable biscuits with improved nutritional quality.