Undesirable Flavor Research Articles

Flavor and Metabolite Profiles of Meat, Meat Substitutes, and Traditional Plant-Based High-Protein Food Products Available in Australia

Demand for plant-based proteins and plant-based food products is increasing globally. This trend is driven mainly by global population growth and a consumer shift towards more sustainable and healthier diets. Existing plant-based protein foods and meat mimetics often possess undesirable flavor and sensory properties and there is a need to better understand the formation of desirable meat-like flavors from plant precursors to improve acceptance of novel high-protein plant foods. This study aimed to comprehensively characterize the non-volatile flavor metabolites and the volatiles generated in grilled meat (beef, chicken, and pork) and compare these to commercially available meat substitutes and traditional high-protein plant-based foods (natto, tempeh, and tofu). Solid phase microextraction with gas-chromatography mass-spectrometry was used for elucidation of the flavor volatilome. Untargeted characterization of the non-volatile metabolome was conducted using Orbitrap mass spectrometry and Compound DiscovererTM datamining software. The study revealed greater diversity and higher concentrations of flavor volatiles in plant-based foods in comparison to grilled meat, although the odor activity of specific volatiles was not considered. On average, the total amount of volatiles in plant-based products were higher than in meat. A range of concentrations of free amino acids, dipeptide, tripeptides, tetrapeptides, nucleotides, flavonoids, and other metabolites was identified in meat and plant-based foods.

Yeast cells for encapsulation of bioactive compounds in food products: A review.

Nowadays bioactive compounds have gained great attention in food and drug industries owing to their health aspects as well as antimicrobial and antioxidant attributes. Nevertheless, their bioavailability, bioactivity, and stability can be affected in different conditions and during storage. In addition, some bioactive compounds have undesirable flavor that restrict their application especially at high dosage in food products. Therefore, food industry needs to find novel techniques to overcome these problems. Microencapsulation is a technique, which can fulfill the mentioned requirements. Also, there are many wall materials for use in encapsulation procedure such as proteins, carbohydrates, lipids, and various kinds of polymers. The utilization of food-grade and safe carriers have attracted great interest for encapsulation of food ingredients. Yeast cells are known as a novel carrier for microencapsulation of bioactive compounds with benefits such as controlled release, protection of core substances without a significant effect on sensory properties of food products. Saccharomyces cerevisiae was abundantly used as a suitable carrier for food ingredients. Whole cells as well as cell particles like cell wall and plasma membrane can act as a wall material in encapsulation process. Compared to other wall materials, yeast cells are biodegradable, have better protection for bioactive compounds and the process of microencapsulation by them is relatively simple. The encapsulation efficiency can be improved by applying some pretreatments of yeast cells. In this article, the potential application of yeast cells as an encapsulating material for encapsulation of bioactive compounds is reviewed.

Application of natural antioxidants in the oxidative stabilization of fish oils: A mini‐review

Fish oils are a source of omega-3 unsaturated fatty acids which are known for their beneficial effects on human health. These acids are highly unstable and are easily oxidized on storage, whereby their nutrition value deteriorate, undesirable flavor develops, and toxic compounds are generated. Antioxidants extend the fish oil shelf-life. However, synthetic antioxidants may annihilate the health-promoting properties of omega-3 fatty acids, which is not the case when natural antioxidants are used. Application of the latter may bring about many benefits. However, the number of approved natural antioxidants is still very low. Therefore, new sources of natural antioxidants are explored among polyphenol compounds in plants, for example, in herbs, spices, or by-products of fruit and vegetable processing. A review of studies addressing the application of natural antioxidants in the extension of fish oil shelf-life is presented and the effectiveness of natural antioxidants in protecting long-chain omega-3 fatty acids is discussed. Practical applications The use of natural antioxidants in foods and food supplements raises no reservations as to the toxicological safety and is accepted by consumers. Many natural antioxidants are highly effective in inhibiting oxidation and may be successfully used to extend the shelf-life of health-promoting omega-3 polyunsaturated fatty acids.

Studies of quality development and major chemical composition of green tea processed from tea with different shoot maturity

Apart from geographical difference and processing method, the maturity of fresh tea shoot is an important factor that determines tea quality. However, the quality development and chemical variation of green tea with tea shoot maturity remain unclear. This study aimed to investigate the metabolic consequences of tea shoot maturity on the taste and aroma quality of green tea by metabolite profiling. In terms of taste quality, a concentration-dependent decrease with tea shoot age was observed in gallic acid and caffeine. The levels of catechin, epicatechin, and epigallocatechin increased with tea shoot maturity, whereas those of epicatechin gallate, epigallocatechin gallate, and total catechins decreased. Furthermore, the maximum contents of most amino acids were recorded in green tea processed from one bud with two leaves. In terms of aroma quality, volatile profiles of green tea were analyzed by gas chromatography–mass spectrometry combined with chemometrics. A total of 32 differential volatile organic compounds showing significant differences were identified and divided into Groups I and II, which contribute undesirable flavor and sweet flowery aroma to tea, respectively. The relative abundance of Group I increased with tea shoot maturity whereas that of Group II decreased. These findings can be used in guiding the production of green tea.

Monitoring the evolution of free and cysteinylated aldehydes from malt to fresh and forced aged beer

During storage, beer staling coincides with a gradual increase in the concentrations of aldehydes resulting in the appearance of undesirable flavours. Cysteinylated aldehydes, also referred to as 2-substituted 1,3-thiazolidine-4-carboxylic acids, have been proposed as potential precursors of this increase. This study aimed to further understand the origin of aldehydes in aged beer, by monitoring both free and cysteinylated aldehydes throughout the brewing process, from the raw materials until the stored product. Quantification of free and cysteinylated aldehydes was performed for two different brews via headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS), respectively. All selected marker aldehydes were quantified in malt, wort, and the resulting fresh and aged beer samples. Cysteinylated aldehydes were quantifiable in malt and up to the wort boiling phase. The highest levels of free aldehydes were found in malt, whereas cysteinylated aldehydes showed highest levels at mashing-in pointing to their formation during both malting and subsequent mashing-in. During beer ageing, an increase in all free aldehydes was measured. In particular, a rise in 2-methylpropanal and furfural is most striking. Although the presented experimental data obtained on malt and brewery samples do support the concept of bound-state aldehydes, cysteinylated aldehydes cannot be consider as the cause of increasing levels of staling aldehydes during beer ageing.

Global transcriptomic analysis of Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 reveals the role of LDB_RS05285 in the post-acidification of yogurt.

During the storage of yogurt, acid-resistant bacteria continue to produce lactic acid (i.e., post-acidification process), leading to undesirable taste and flavor. Many methods have been proposed to inhibit post-acidification. However, the specific genes involved during this biological process have not yet been systematically studied. Hence, herein, we assessed the culture starter Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 with regards to its transcriptomes under in vitro acid- and cold-culture conditions. Through differential gene expression analysis, we screened out 69 candidate genes that persistently responded to acid with or without cold stress. qPCR was then used to determine the in situ expression levels of these candidate genes at different stages of yogurt fermentation and storage. Genes whose expression levels did not change much from the end of fermentation to the early stage of yogurt storage were more likely to be post-acidification genes, as such stability indicated that they were not affected by cold stress. LDB_RS05285 was determined to be one such gene; the overexpression of this gene showed that the increase of gene expression could reduce the acid production of the strain without affecting normal growth. Therefore, the genetic manipulation techniques that increased the expression level of the LDB_RS05285 gene might have the potential to inhibit the post-acidification of yogurt. Thus, LDB_RS05285 plays an important role in the post-acidification process and would become a new target for regulating yogurt post-acidification.

Influence of Oil Types and Prolonged Frying Time on the Volatile Compounds and Sensory Properties of French Fries.

In order to study the flavor of French fries (FFs) prepared in different frying oils, we identified and compared the volatiles of FFs fried in high-oleic sunflower oil (HSO), sunflower oil (SO), linseed oil (LO), and palm oil (PO) during prolonged 24 h frying time. 47 different kinds of volatiles were presented, and aldehydes were the most abundant compounds. The FFs prepared in SO were rich in alkadienals, especially the (E, E)-2,4-decadienal, thus inducing the highest deep-fried odor. The content of alkenals was higher in FFs prepared in HSO, among which (E)-2-nonenal and 2-undecenal provided the undesirable oily flavor. Whereas, FFs prepared in PO were rich in alkanals, and showed an undesirable green aroma because of hexanal. Besides, the aldehydes in FFs fried in LO were the least with more undesirable flavor substances (e.g. (E, E)-2,4-heptadienal). In addition, except for the FFs fried in LO, the aldehydes in other FFs showed an increasing trend. While, the volatiles from the Maillard reaction (e.g. pyrazines) showed no clear pattern. Meanwhile, frying process had optimum frying window (approximately 12 h with total polar compounds content of 14.5%-22.2% in different oils), and the French fries prepared in this period obtained higher flavor score. Therefore, the comparison related to volatiles of FFs provided a basis for the flavor control to a certain extent.

Antioxidant activity ofEryngium campestreL.,Froriepia subpinnata, andMentha spicataL. polyphenolic extracts nanocapsulated in chitosan and maltodextrin

The antioxidant activity of Eryngium campestre, Froriepia subpinnata, and Mentha spicata polyphenolic extracts nanocapsulated in chitosan (CS) and maltodextrin (MD), and incorporated in canola oil under accelerated oxidation condition was evaluated. The zeta potential of nanoemulsions coated with 10%MD, 9.5%MD:0.5%CS, 9%MD:1%CS, and 8.5%MD:1.5%CS was −7.51 to −7.68, −0.06 to −0.08, 1.20 to 1.25, and 1.85 to 1.89 mV, respectively, also the average particle size was 52.73–52.91, 50.33–50.73, 26.05–27.29, and 15.78–15.92 nm, respectively. The highest (>91%) and lowest (70%–75%) encapsulation efficiency of the extracts obtained for 8.5%MD:1.5%CS and 10%MD, respectively. IC50 (DPPH assay) and EC50 (FRAP assay) of 8.5%MD:1.5%CS-treated samples were the lowest among the different formulations. The E. campestre extract nanoencapsulated with 8.5%MD:1.5%CS had the best antioxidant capacity in canola oil, followed by 9%MD:1%CS, 9.5%MD:0.5%CS, and 10%MD. In the conclusion, the encapsulation with 8.5%MD:1.5%CS is suggested as an efficient coating formulation to enhance the antioxidant efficacy of the extracts. Practical applications Despite the great potential of herbal extracts as food antioxidants and antimicrobials, low solubility in oil and high volatility of phenolic compounds cause problems in their usage. To protect hydrophobic bioactive compounds against processing conditions in food preparation, increase their solubility and stability in the food matrix, and prevent undesirable flavors, nanoencapsulation, and nanoemulsifying of herbal extracts are used. Due to the small size, transparency, and high thermodynamic stability against precipitation and accumulation in food complex, nanoemulsions are most preferred. So, the results of this work will help design the proper formulation of coatings for bioactive compounds applied in the food industry.

Elucidating mechanisms involved in flavor generation of dry-aged beef loins using metabolomics approach

The present study was conducted to identify flavor-related chemical compounds and to elucidate beef flavor development in response to dry-aging. Paired grass-fed beef loins (n = 18) were obtained at 7 d postmortem, cut into two sections and assigned to 3 aging methods: conventional dry-aging (DA), vacuum packaged wet-aging (WA) and dry-aging in a bag (DW) for 28 days. Following aging, samples were analyzed for UPLC-MS metabolomics, volatile, fatty acid profiling, and consumer sensory comment analysis. Greater number of proteins and nucleotides derived metabolites were liberated in dry-aged samples compared to WA (P < 0.05). In particular, the liberation of gammaglutmayl peptides and glutamine metabolites through the glutathione metabolism were identified. While fatty acid profile was not affected by treatments (P > 0.05), higher concentrations of volatile compounds were found in the dry-aged (P < 0.05). Dry-aging process decreased the presence of terpenoid and steroid lipid group, which could possibly result in reducing undesirable flavor of grass-fed beef.

Utilization of pulsed UV light for inactivation of Salmonella Enteritidis on shelled walnuts

Due to their nutritional value, walnut consumption has been increasing worldwide, however outbreaks caused by walnuts are still of concern. Current chemical methods in walnut industry to prevent pathogenic microorganisms are not preferred by the consumer while thermal treatments may cause undesired flavor. UV light is the portion of the electromagnetic spectrum with wavelengths of 100–400 nm. UV light in the 100–280 nm range has germicidal capabilities. Walnut halves and pieces were inoculated with Salmonella Enteritidis and treated in a pulsed UV light system chamber at three different distances for varying treatment times. Maximum log reduction of 3.18 CFU/g was obtained after pulsed UV treatment at 8 cm for 45 s. Measurement of energy levels revealed an increase in energy and temperature with longer treatment time and shorter distance from the strobe to the sample. Furthermore, quality parameters were assessed to determine the influence of pulsed UV light treatment on the quality of walnuts. The quality results showed no significant differences between control and pulsed UV treated samples. Overall, this study demonstrated that pulsed UV light technology is a promising method to decontaminate walnuts without using any chemicals, which will open doors for the food industry.

Barrel-Induced Variation in the Microbiome and Mycobiome of Aged Sour Ale and Imperial Porter Beer

Traditional styles of beer that undergo spontaneous fermentation and/or maturation in oak barrels are becoming increasingly popular amongst craft beer consumers. These products are costly to produce, partly because some barrels develop undesirable flavor profiles and are excluded from the final blend. As a first step towards understanding variation in beer quality that occurs during barrel maturation, next-generation sequencing was used to profile the bacterial microbiome and fungal mycobiome of three beers; an American Coolship Ale (ACA), an aged sour ale, and an Imperial Porter. For the aged sour ale, produced across three years, it was observed that while there were significant differences in key lactic and acetic acid bacterial genera according to beer age, within each production batch there was substantial barrel-induced variation in microbiome profiles. Similarly, for the Imperial Porter significant differences were observed in the relative abundance of Saccharomyces cerevisiae and Brettanomyces bruxellensis across the barrel population at two sampling time points. Overall, the results point towards barrel-induced variation in the rate of “microbial maturation”. Further work to understand the underlying cause of this variation will enable brewers to better predict and monitor their barrel projects to achieve more consistent outcomes.

Can hydro-thermo-mechanical treatment by instant controlled pressure-drop (DIC) be used as short time roasting process? Effect of processing parameters on sensory, physical, functional, and color attributes of Egyptian carob powder

This study deals with the manufacture of a specific cocoa-like powder from Egyptian carob. The crucial unit operation consists of texturing/roasting unseeded carob kibbles, with the aim being to ensure perfect control of the chemical transformations that generate the desired flavor, drying to remove excess moisture, deodorizing to eliminate the undesirable flavor, and texturing to favor the physical/micro-mechanical changes that regulate the microstructure of the end product, in order to obtain an expanded-granule powder that can be used in many food formulations. The effect of saturated steam pressure of 0.30-0.60MPa (133.5-158.8°C) and processing time of 40-70s, on the sensory attributes, physical and functional properties, and color characteristics were evaluated and optimized using response surface methodology (RSM). DIC-texturing/roasting could be used to improve the sensory and color characteristics, increase the expansion ratio and oil holding capacity, and decrease the bulk density of DIC-textured/roasted carob powder. The desired quality of textured/roasted carob powder was obtained at 0.60MPa (158.8°C) for 55s (experimental conditions) with water holding capacity close to those of non-textured/unroasted sample. DIC can be used as a coupled process of texturing and roasting at 0.60MPa for 68s as predicted by RSM.

Optimization of the Emulsifying Properties of Food Protein Hydrolysates for the Production of Fish Oil-in-Water Emulsions.

The incorporation of lipid ingredients into food matrices presents a main drawback—their susceptibility to oxidation—which is associated with the loss of nutritional properties and the generation of undesirable flavors and odors. Oil-in-water emulsions are able to stabilize and protect lipid compounds from oxidation. Driven by consumers’ demand, the search for natural emulsifiers, such as proteins, is gaining much interest in food industries. This paper evaluates the in vitro emulsifying properties of protein hydrolysates from animal (whey protein concentrate) and vegetal origin (a soy protein isolate). By means of statistical modelling and bi-objective optimization, the experimental variables, namely, the protein source, enzyme (i.e., subtilisin, trypsin), degree of hydrolysis (2–14%) and emulsion pH (2–8), were optimized to obtain their maximal in vitro emulsifying properties. This procedure concluded that the emulsion prepared from the soy protein hydrolysate (degree of hydrolysis (DH) 6.5%, trypsin) at pH 8 presented an optimal combination of emulsifying properties (i.e., the emulsifying activity index and emulsifying stability index). For validation purposes, a fish oil-in-water emulsion was prepared under optimal conditions, evaluating its physical and oxidative stability for ten days of storage. This study confirmed that the use of soy protein hydrolysate as an emulsifier stabilized the droplet size distribution and retarded lipid oxidation within the storage period, compared to the use of a non-hydrolyzed soy protein isolate.

Activated Kaolin Minerals as Bleaching Clays for Prolonging the Useful Life of Palm Oil in Industrial Frying Operations

AbstractDuring frying operations, vegetable oils break down and compounds with undesirable flavors are produced. Various procedures have been developed to extend the useful life of frying oils, including treatment with bleaching clays. In this article, we describe the activation of kaolin minerals by a combination of grinding and chemical treatments, and report their performance in removing breakdown products generated in palm oil that had been used for 20 hours continuous frying. There was little influence of the original kaolin mineral form on the ability to reduce the free fatty acid (FFA) contents, and grinding only changed FFA reduction from ∼32% to ∼36%. However, much greater FFA reductions were obtained after chemical treatment of the ground clays, and the best performing kaolin product gave similar FFA reduction to a commercial bleaching clay (∼76% and ∼77%, respectively). This activated kaolin also produced a reduction in viscosity at 40 °C from ∼73 to 48.4 cSt (compared to 45.5 cSt in the unused oil), and in the peroxide value from 30.0 to 22.0 meq/kg (compared to 10.0 meq/kg in the initial oil). Thus, activated kaolin samples represent a cheap and convenient alternative to conventional bleaching clay for improving common quality parameters in used palm oil, although we also found that the optimum kaolin preparation conditions were different from those that have been reported for raw rice bran oil refining.

Effect of roasting as a premilling treatment on the functional and bread baking properties of whole yellow pea flour

AbstractBackground and objectivesThere is a growing global interest in partially replacing wheat flour with pulse flours in foods, including bread. However, undesirable flavors associated with pulse flours, especially yellow pea flour, have limited their use in foods. Pretreating pulses prior to milling offers a possible solution for improving the flavor of pulse flours. The objective of this research was to examine the effect of oven roasting and Revtech roasting (with and without steam) on the compositional, functional, and bread baking properties of whole yellow peas.FindingsRegardless of the roasting method used, a roasting temperature of 120°C resulted in flours that retained good functionality and bread baking properties with less detrimental changes in flour color. Bread made with peas roasted at 120°C also had reduced aroma and flavor properties compared to bread made with untreated peas.ConclusionsThe strong aroma and flavor properties of yellow peas can be reduced by pretreating the peas prior to milling using conventional oven roasting and Revtech roasting. By selecting the appropriate roasting temperature, flour functionality for bread baking can be maintained.Significance and noveltyRoasting is a useful premilling treatment for yellow peas. Reducing the off‐flavors associated with pulses while maintaining flour functionality will allow for greater use of pulse flours in formulating foods.

Flavor modification of yellow pea flour using supercritical carbon dioxide + ethanol extraction and response surface methodology

Reduction of volatile aroma compounds that are the source of undesirable flavor is crucial for quality, acceptability, and marketability of products made with pea (Pisum sativum L.) flour. Supercritical carbon dioxide extraction was applicable for flavor modification of pea flour. Percentage ethanol, temperature, and pressure were optimized using a central composite rotatable design under response surface methodology. The minimum total volatile content (0.55 μg/g) was obtained significantly (p < 0.05) under optimum conditions, which were ethanol (22%), temperature (86oC), and pressure (42.71 MPa). Furthermore, flour color was lighter when processed using at optimum conditions. Through the response surface model, only ethanol, temperature, and quadratic term of ethanol were significant (p < 0.05). Principal component analysis revealed total volatile content, sensory attributes, and color values were highly interrelated. The data support supercritical carbon dioxide extraction as a viable method for removal of undesirable volatiles from pulse flour.

Determination of nucleotide and enzyme degradation in haddock (Melanogrammus aeglefinus) and herring (Clupea harengus) after high pressure processing.

BackgroundThe degradation of nucleotides and their enzymes had been widely used to evaluate fish freshness. Immediately after fish death, adenosine triphosphate (ATP) degrades into inosine-5-monophosphate (IMP) via adenosine-5-diphosphate (ADP) and adenosine-5-monophosphate (AMP). IMP degradation continues to produce inosine (ino) and hypoxanthine (Hx) and further deteriorates the fish by producing xanthine and uric acid. The dephosphorylation of IMP to Ino is carried out by the enzyme 5′-nucleotidase (5′-NT), whereas the degradation of Ino to Hx is carried out by the enzyme nucleoside phosphorylase (NP). This study assesses the application of high pressure processing (HPP) in two species of fishes; haddock (Melanogrammus aeglefinus) and herring (Clupea harengus) as a means to extend the shelf-life by slowing down the rate of nucleotides degradation.MethodsHaddock (Melanogrammus aeglefinus) and herring (Clupea harengus) fillets were subjected to HPP at 200, 250 and 300 MPa for 1 and 3 min before being stored for 14 days. In addition, 5′-NT and NP enzyme activities were determined on both fish species that were subjected to 100–600 MPa for 1 and 3 min.ResultsAdenosine triphosphate, ADP and AMP in both haddock and herring were lower at higher pressure levels. Inosine (Ino) increased (p < 0.05) after treatment at higher pressures in both species. Hx in herring decreased significantly (p < 0.05) at higher pressures but not in haddock. K values are the ratio of Ino and Hx to all nucleotides. K values in haddock were not significantly (p > 0.05) affected by the pressure treatment. H values are ratio of Hx to the sum of IMP, Ino and Hx. H values in haddock were significantly decreased (p < 0.05) with increasing pressure level. F values are ratio of IMP to the sum of IMP, Ino and Hx. F values showed no significant effects (p > 0.05) after pressure treatment. Furthermore, K values in control herring were significantly higher (p < 0.05) than those of the pressure-treated samples. H values in herring decreased significantly (p < 0.05) with increasing pressure level. F values in herring showed no significant effects (p > 0.05) after pressure treatment. Pressure treatment brought a significant decrease (p < 0.05) in protein content in both haddock and herring. 5′-NT activity was 20–35 fold higher compared to NP activity in haddock and 15–44 fold higher than NP activity in herring. 5′-NT and NP activities decreased significantly with increasing pressure level in both species.DiscussionHigh pressure processing effectively slows down the conversion of Ino to Hx, delaying the undesirable flavour that develops in spoiling fish. The autolytic conversion of IMP to Ino by endogenous 5′-NT predominates in the earliest stages of storage is an autolytic process. However, both bacterial and endogenous NP enzymes are probably responsible for the gradual accumulation of Hx in fish. K values are recommended as a useful measurement of fish freshness.

Effect of premilling treatments on the functional and bread‐baking properties of whole yellow pea flour using micronization and pregermination

AbstractBackground and objectivesThere is interest in partially replacing wheat flour with pulse flours in bread. However, flavor of pulse flours may be detrimental to the final product. Processing pulses prior to milling, using micronization and pregermination (early seed germination without radicle emergence), was investigated as a way to improve the flavor of yellow pea flour while maintaining or improving flour functionality.FindingsMicronization and pregermination of peas prior to milling resulted in changes to flour particle size, color, and compositional and functional properties of the flours. Peas tempered to 18%–20% and micronized to 105–110°C produced a flour that was similar in baking properties to the flour milled from untreated peas with the exception of crumb firmness and aroma and flavor of the bread. All bread made from micronized peas tended to have reduced crumb firmness and improved aroma and flavor properties compared to bread made with untreated peas. Results for the pregerminated peas showed that the flour had higher starch damage and WAC and lower peak and final viscosities compared to the flour milled from untreated peas. Bread baked from pregerminated peas had lower bread quality in terms of bread scores, volume, crumb color, and C‐cell properties, but the bread had reduced crumb firmness and improved aroma and flavor properties, compared to bread made with untreated peas.ConclusionsBoth micronization and pregermination were suitable premilling treatments for yellow peas. Pregermination, however, warrants additional research to determine whether flour and baking properties can be improved.Significance and noveltyPretreating yellow peas using either micronization or pergermination prior to milling were successful in reducing undesirable flavors associated with pea flour. Depending on the treatment and conditions used, flour functionality and bread‐baking properties were maintained.

Evaluation of hot water and microwave blanching on qualities and sensory characteristics of water dropwort (Oenanthe javanicaDC.)

In the present study, water dropwort was comparatively treated in hot water blanching (HWB) and microwave blanching (MWB). The changes in polyphenol oxidase (PPO), weight loss, phytochemicals, color, firmness, flavor, and sensory evaluation were investigated. The sensory preference was predicted via artificial neural network (ANN) model. Results showed that high heating intensity inactivated PPO activity, enhanced lightness and greenness, but caused damage to the texture both in HWB and MWB. Moreover, MWB yielded lower weight loss and retained higher contents of ascorbic acid, soluble proteins, sugars, flavonoids, and total polyphenols than HWB. However, E-nose and E-tongue analysis indicated that HWB was more conducive for reducing undesired flavor. Importantly, ANN model suggested that the color and taste were the remarkable factors influencing sensory preference. Overall, blanching at 600 W for 1 min was predicted as the preferable condition for meeting sensory acceptability, and MWB could be a good alternative to HWB. Practical applications Blanching is usually considered as a suitable pretreatment to inactivate enzymes of the fruits and vegetables. Microwave blanching has gained significant momentum due to its capability of providing rapid and volumetric heating. The results of this study provide substantial information for comparing the effects of HWB and MWB on the qualities and sensory properties of water dropwort. Moreover, highlighting sensory analysis might be of importance to obtain insight into consumer attitudes toward products. Furthermore, artificial neural network model is served for comparing the influence of HWB and MWB on the sensory preference, which would be more valuable to control the food quality and satisfy the sensory requirements in actual production.

Microencapsulation performance of Fe-peptide complexes and stability monitoring.

Iron supplementation presents several challenges, such as low bioavailability, high reactivity and a metallic taste. Iron absorption is enhanced by complexing with organic compounds such as peptides, while microencapsulation is an alternative to protect the mineral and mask undesirable flavors. Fe-peptide complexes were obtained by reacting small whey peptides (< 5 kDa) with iron (from ferrous sulfate) under controlled conditions. Maltodextrin (MD) and polydextrose (PD) were used as the wall materials and spray dried to form particles containing the active Fe-peptide. The conditions of enzymatic hydrolysis with the bacterial endopeptidase produced from Bacillus licheniformis were optimized to achieve a high degree of cleavage (~20% degree of hydrolysis). The physicochemical and structural properties of the microparticles were evaluated during storage (365 days). The encapsulation process showed high efficiency (84%) and process yield (≥90%). The iron dialyzability and uptake by Caco-2 cells from microparticles were at least 3-fold higher than the ferrous sulfate. The water content and water activity varied from 3.0 to 5.7% and from 0.29 to 0.44, respectively, after 365 days. SEM revealed morphological stability during storage and EDX showed the presence of iron ions at the surface of the microparticles, which could be free or complexed. The microparticles can be an alternative of higher bioavailable iron besides the further protection and iron stability which the microparticles may present when compared with the Fe-peptide complexes. Future studies could demonstrate the feasibility of applying these microparticles in formulation for food supplementation, concerning bioavailability and sensory aspects.