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Oleogelation offers the possibility to reduce the saturated fatty acid (SAFA) content while maintaining the desired organoleptic properties. Hereby, SAFA are replaced by other structurants which can create a three-dimensional network that immobilizes the liquid oil. Depending on the type of structurants, different structuring routes are identified. The use of monoglycerides (MAGs) as structurants is a promising approach thanks to their great self-assembling properties. However, implementation into the food industry is still hampered due to insufficient characterization. This research includes a multiscale analysis of two dynamically produced MAG-based oleogels as a function of the storage time (up to 8 weeks). Slight differences in the production process resulted in differences in techno-functional properties between the MAG-based oleogels MO1 and MO2. MO1 consisted of larger crystals, which resulted in a lower rigidity, lower stability and lower oil binding capacity compared to the other oleogel (MO2). On the nanoscale, it was found that the crystal nanoplatelets (CNPs) of MO1 contained a higher number of lamellae compared to the MO2. Additionally, the results obtained with ultra-small angle X-ray scattering indicated a larger equivalent diameter for the CNPs of MO1. As a function of the storage time, both oleogels did not show major structural changes up to 8 weeks of storage.

β-carotene is a carotenoid with provitamin A activity and other health benefits, which needs to become bioavailable upon oral intake to exert its biological activity. A better understanding of its behaviour and stability in the gastrointestinal tract and means to increase its bioavailability are highly needed. Using an in vitro gastrointestinal digestion method coupled to an intestinal cell model, we explored the stability, gastrointestinal bioaccessibility and cellular uptake of β-carotene from microparticles containing carotenoid extracts derived from mango by-products. Three types of microparticles were tested: one with the carotenoid extract as such, one with added inulin and one with added fructooligosaccharides. Overall, β-carotene was relatively stable during the in vitro digestion, as total recoveries were above 68 %. Prebiotics in the encapsulating material, especially inulin, enhanced the bioaccessibility of β-carotene almost 2-fold compared to microparticles without prebiotics. Likewise, β-carotene bioaccessibility increased proportionally with bile salt concentrations during digestion. Yet, a bile salts level above 10 mM did not contribute markedly to β-carotene bioaccessibility of prebiotic containing microparticles. Cellular uptake experiments with non-filtered gastrointestinal digests yielded higher absolute levels of β-carotene taken up in the epithelial cells as compared to uptake assays with filtered digests. However, the proportional uptake of β-carotene was higher for filtered digests (24 – 31 %) than for non-filtered digests (2 – 8 %). Matrix-dependent carotenoid uptake was only visible in the unfiltered medium, thereby pointing to possible other cellular transport mechanisms of non-micellarized carotenoids, besides the concentration effect. Regardless of a filtration step, inulin-amended microparticles consistently resulted in a higher β-carotene uptake than regular microparticles or FOS-amended microparticles. In conclusion, encapsulation of carotenoid extracts from mango by-products displayed chemical stability and release of a bioaccessible β-carotene fraction upon gastrointestinal digestion. This indicates the potential of the microparticles to be incorporated into functional foods with provitamin A activity.

Food-approved colloidal particles that can construct stable emulsions, but destabilize on purpose using a specific stimulus like pH change would be of great importance to food and pharmaceutical industries (bioactive delivery). However, such edible Pickering stabilizers are quite rare, since they must possess superb interfacial activity (rapid, strong and reversible adsorption at oil-water interface) to be efficient in stabilization of these unique systems. Herein, we report the formation of sodium caseinate (SC)-κappa-carrageenan (kC) colloidal conjugates that can offer such Pickering ability. SC-kC conjugates were prepared by wet-heating Maillard reaction after sonication pre-treatments (400 W, 20 kHz) for 10, 20, and 30 min. The SC-kC conjugation was confirmed by Fourier transform infrared spectroscopy, CD spectra, intrinsic fluorescence analysis, and glycation degree (GD). With increased sonication duration, a higher GD (59.75 ± 0.69% in 30 min) was observed which led to improved interfacial activity (higher adsorption quantity and rate at interface), lower particle size (

The effect of different dosages of anhydrous milk fat (AMF) (25%, 50% and 75%, w/w) on shear-crystallization of fat blends made of refined palm oil, refined palm stearin, and rapeseed oil was studied. Classical techniques as differential scanning calorimetry (DSC), pulsed field gradient nuclear magnetic resonance (pfg-NMR), rheometer, and X-ray diffraction (XRD) were applied to evaluate the crystallization kinetics of fat blends as well as the fat compatibility between components in rapid cooling (15 degrees C min(-1)), isothermal crystallization (at 15 degrees C), and storage (5 degrees C). Obtained results revealed that the mixtures of palm oils and milk fat had a low compatibility. The co-crystallization between triacylglycerols (TAG) of milk fat and of palm oil occurred during isothermal crystallization and storage resulting in slower crystallization kinetics and the formation of some eutectic mixtures.

Shortenings and margarines are semi-solid lipid-continuous products which are traditionally structured by triacylglycerols containing mainly trans or saturated fatty acids. Since an overconsumption of trans and saturated fatty acids is linked with cardiovascular health diseases, alternative structurants are investigated. In this respect, natural waxes have received a lot of attention as they are known to form a three-dimensional matrix which enables liquid oil to be entrapped at low concentrations. However, wax oleogels are still quite shear sensitive, which limits their use in certain food applications. Besides, including higher amounts of waxes to create stronger gel networks may result in sensory defects. This chapter therefore discusses the potential of combining waxes with common hardstock fats to produce hybrid fat systems. This approach allows fat systems to be created which are partially reduced in trans or saturated fatty acids but maintain the desired rheological and functional properties.

This paper reports the production of O/W high internal phase emulsions (HIPEs) using protein-anionic poly-saccharide Maillard conjugates. First, Maillard conjugates were prepared from soy protein isolate (SPI) or sodium caseinate (SC) proteins and Alyssum homolocarpum seed gum (AHSG) or kappa-carrageenan (kC) polysaccharides. The conjugation process was confirmed and monitored by UV spectrophotometry, Fourier transform infrared, circular dichroism, fluorescence spectroscopies, and differential scanning calorimetry. Under the optimized re -action conditions, SC-AHSG conjugates exhibited the highest glycation degree and emulsifying properties. Next, HIPEs were made using the optimized conjugates, and their microstructure, droplet size, and physical stability were evaluated. The emulsion stabilized by SC-AHSG conjugate had the lowest mean droplet size (363.07 & PLUSMN; 34.56 nm), orderly-packed oil droplets with monomodal distribution, the highest zeta potential (-27.70 & PLUSMN; 0.70 mV), high storage stability (no creaming or oil-off) and was ultra-stable against environmental stresses. Results of this research are helpful for development of emulsion-based foods with novel functionality.

Buckwheat is an important starch source because of its health benefits. In this study, buckwheat starches isolated from 12 varieties were analyzed based on the morphological, structural and physicochemical properties. The results showed that starch samples from different varieties had high purity with the total starch ranging from 91.29 to 95.11%, while showing significant differences in ash content (0.12-0.25%), protein content (0.26-0.34%) and amylose content (29.55-36.13%), respectively. All samples presented spherical and irregular shapes and typical A-type crystalline structure, but obvious differences in granule size distribution and relative crystallinity (26.37-35.21%) were observed among 12 varieties. Starch samples differed in lamellar structures, showing higher values of thickness of the samples with higher amylose content. In addition, buckwheat starches with higher amylose content showed higher values in light transmittance and rheological properties, while starch samples with lower amylose content obtained higher values in terms of water solubility, swelling power, pasting behaviors and thermal parameters. The principal component analysis and cluster analysis based on starch property parameters indicated that there were significant similarities and differences among 12 varieties, which might be related to the genotypes. This study would provide valuable information for the full use of buckwheat starch in food and non-food industries.

Oil-in-water-in-oil (O/W/O) double emulsions are recognized as an advanced design route for oil structuring that shows promising applications in the pharmaceutical, cosmetic, and food fields. This review summarizes the main research advances of O/W/O double emulsions over the past two decades. It mainly focuses on understanding the preparation strategies, stabilization mechanism, and potential applications of O/W/O double emulsions. Several emulsification strategies are discussed, including traditional two-step emulsification method, phase-inversion approach, membrane emulsification, and microfluidic emulsification. Further, the role of interfacial stabilizers and viscosity in the stability of O/W/O double emulsions will be discussed with a focus on synthetic emulsifiers, natural biopolymer sand solid particles for achieving this purpose. Additionally, analytical methods for evaluating the stability of O/W/O double emulsions, such as advanced microscopy, rheology, and labeling assay are reviewed taking into account potential limitations of these characterization techniques. Moreover, possible innovative food applications are highlighted, such as simulating fat substitutes to decrease the trans- or saturated fatty acid content and developing novel delivery and encapsulation systems. This review paves a solid way for the exploration of O/W/O double emulsions toward large-scale implementation within the food industry.

Quinoa cultivation has gained increasing interest in Europe but more research on the characteristics of European varieties is required to help determine their end use applications. A comparative study was performed on 13 quinoa varieties cultivated under North-West European field conditions during three consecutive growing seasons (2017-2019). The seeds were milled to wholemeal flour (WMF) to evaluate the physicochemical properties. The WMFs of 2019 were characterized by the highest water absorption capacity (1.46-2.06 g/g), while the water absorption index (WAI) between 55 °C (2.04-3.80 g/g) and 85 °C (4.04-7.82 g/g) increased over the years. The WMFs of 2018 had the highest WAI at 95 °C (6.48-9.48 g/g). The pasting profiles were characterized by a high viscosity peak (1696-2560 mPa.s) and strong breakdown (-78-643 mPa.s) in 2017. The peak viscosity decreased in 2018 and 2019 (823-2492 mPa.s), while breakdown (-364-555 mPa.s) and setback (19-1037 mPa.s) increased. Jessie, Summer Red, Rouge Marie, Vikinga, and Zwarte WMFs were characterized by low WAIs and high shear resistance. Bastille WMF developed high viscosities and, along with Faro WMF, showed a high breakdown. The wide variation in physicochemical properties suggests that the potential food applications of WMFs depend on the variety and growing conditions.

The aims of this study were (i) screening of antifungal activity of thyme essential oil on Penicillium paneum; (ii) development of growth/no-growth models (G/NG); and (iii) validation of the G/NG models by performing bread baking trials. The screening method was based on the measurement of fungal growth in a semi-solid medium through optical density. The combined influence of aw (0.88–0.97), pH (4.8–7.0), temperature (22 and 30 °C), time (0–144 h) and varying concentrations of thyme oil (0–2 μL/mL YES) were assessed. Growth of P. paneum at aw 0.88 was significantly reduced compared to aw 0.93–0.97. A slight pH effect was observed at aw 0.93; growth was delayed at pH 6 compared to pH 4.8. The lowest concentration of thyme oil preventing growth during 144 h of incubation was 1 μL/mL medium. According to the results of the shelf-life test of par-baked bread, fungal growth was inhibited for more than 45 days using 0.3 mL thyme oil/100 g dough. To conclude, this study recognized the potential of using G/NG models to develop better product formulations and to facilitate product innovation.

Pea protein-based delivery systems have drawn much attention in the food and pharmaceutical fields in recent years. However, its broad application faces great limitations because of the low solubility. Here, we present a novel and effective approach to overcome this difficulty and enhance the techno-functional characteristics, especially emulsifying stability, of the pea protein isolate (PPI). By combining pH-shifting with ultrasound and heating (PUH), we concluded that the solubility of PPI greatly increased from 29.5 % to 90.4 %, whereas its surface hydrophobicity increased from 1098 to 3706. This was accompanied by the changes of PPI structure, as shown by circular dichroism and scanning electron microscopy. In addition, the modified PPI was applied to stabilize sunflower oil-in-water emulsions. The droplet size of the emulsion with PUHP was reduced and its emulsion stability was significantly elevated. Taken together, we propose a novel combined approach to prepare modified PPI with high solubility and emulsion stability. We expect our method will have a wider application in modifying plant proteins and improving their industrial processing.

A sound fundamental knowledge of the seed and flour characteristics of pseudocereals is crucial to be able to promote their industrial use. As a first step towards a more efficient and successful application, this study focuses on the seed characteristics, chemical composition and technological properties of commercially available pseudocereals (amaranth, quinoa, buckwheat). The levels of starch, fat, dietary fiber and minerals were comparable for amaranth and quinoa seeds but the protein content is higher in amaranth. Due to the high amount of starch, buckwheat seeds are characterised by the lowest amounts of fat, dietary fibre and minerals. Its protein content ranged between that of amaranth and quinoa. Buckwheat seeds were larger but easily reduced in size. The lipid fraction of the pseudocereals mostly contained unsaturated fatty acids, with the highest prevalence of linoleic and oleic acid. Palmitic acid is the most abundant unsaturated fatty acid. Moreover, high levels of P, K and Mg were found in these pseudocereals. The highest phenolic content was found in buckwheat. Amaranth WMF (wholemeal flour) had a high swelling power but low shear stability. The pasting profile strongly varied among the different quinoa WMFs. Buckwheat WMFs showed high shear stability and rate of retrogradation.

Lauric fat blends aimed for bakery shortening were prepared as a ternary mixture characterised by three distinct melting peaks on their differential scanning calorimeter (DSC) melting thermograms. Those melting peaks closely correlated to the high, medium, and low melting fractions (HMF, MMF and LMF) in the blends. In the simpler binary mixture, hard fats, (i.e. palm stearin and fully hydrogenated rapeseed oil) formed an ideal solubility in different liquid oils [i.e. medium chain triacylglycerol oil (MCI-oil) and high oleic sunflower oil (HOSO)]. However, slight deviations from ideality were observed when liquid oils were replaced by lauric oils (i.e. palm kernel oil and coconut oil). In the more complex ternary mixture, the I HMF formed an ideal solubility in both the MMF and LMF within the range of given formulas. In addition, the interaction of solid crystals in lauric fat blends was of monotectic behaviour as shown in the isosolid diagram. Nevertheless, the influence of solubility seemed to override that of solid interaction. Both the solubility curves and isosolid lines can provide valuable information about the interaction of HMF, MMF and LMF in lauric fat blends. Therefore, they are useful for improving the formulation of plastic fats.

The production of composite or double-layer (DL) bread was optimized to reduce the amount of the chemical preservative calcium propionate. It was validated using sourdough (SD) in the crust (0–80 g/100 g crust dough). Par-baked (PB) and fully baked (FB) breads were evaluated based on their shelf-life extending, bread technological and sensorial properties. The shelf-life of PB bread was increased with ≥60 g SD/100 g crust dough for air packaged and ≥20 g SD for modified atmosphere packaged (MAP) breads. Use of 60 g SD/100 g crust dough was sufficient to achieve the same level of preservation with or without MAP. Par-baked and fully baked bread were mould free for respectively 7 and 30 days using 60 g sourdough in 100 g crust dough. Specific volume decreased for PB bread containing 40–60 g SD/100 g crust dough and for FB bread with 80 g SD/100 g crust dough. Accordingly, crumb hardness was impaired under the latter conditions.

The application of dynamic-crystallization (a combination of shear with rapid cooling) often plays an important role in the production of industrial fat-based products such as shortenings/margarines but has been rarely reported. In this study, three blends of palm oil (PO) with anhydrous milk fat (AMF) (0, 25 and 50% AMF, w/w) were rapidly crystallized under static (using freezer) and dynamic conditions (using a benchtop scraped surface heat exchanger). Various techniques including differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized light microscopy (PLM), rheology and texture analysis were applied to investigate physicochemical properties of fat blends as well as their crystal morphology upon the long-term storage (4 weeks) at 5 °C and 15 °C. The results revealed that high cooling rate of dynamic-crystallization not only affected melting behavior of fat blends but also prevented the polymorphic transformation from β’ to β crystals. Besides, the application of shear during fat crystallization helped to improve significantly the gel strength of produced shortenings. Although post-crystallization of low melting triacylglycerols (TAGs) occurred for all produced shortenings during storage at 5 °C which was accompanying with a firmness increase, it was more considerable for samples owning higher AMF content. Moreover, this phenomenon promoted the sintering as well as Ostwald ripening between fat crystals of dynamic-crystallized fat blends resulting in the formation of unwanted large aggregates (or granular crystals) with the size ranging from 100 to 500 μm.

The impact of processing conditions on the microbial quality of par-baked wheat and sourdough bread was investigated. Processing conditions included par-baking time (8 and 13 min), temperature (150 and 200 °C), amount of steam (200 and 600 mL), and packaging (air and modified atmosphere (MA)). Total anaerobic mesophilic plate counts, moulds and yeasts and spore-forming bacteria, together with pH and aw of the par-baked breads were evaluated. Data were used to make predictive models showing the impact of the main effects and their interactions. Sourdough addition could extend the time of acceptable bread quality based on the anaerobic counts from 8 to more than 13 days. Visual growth of moulds and yeasts (presence/absence of single spots) was most efficiently suppressed by the combination of MA-packaging and the highest baking temperature and time. Microbiological analysis of moulds and yeasts however, showed that again sourdough had the best preservation potential, followed by MA-packaging. This study showed that adjusting the par-baking conditions, bread composition and packaging can increase the shelf-life of par-baked bread in a natural way.

Plant oils have potential as antimicrobial ingredients in bread. However, they may influence bread production. This study compares the influence of blackcurrant (BC), cumin seed (CS), thyme (TH) and wheat germ (WG) oil on the technological quality of dough/bread, as well as their antifungal activity. The influence of the oils was tested on the water absorption and kneading properties of dough, elasticity, starch gelatinization and yeast activity and were compared with a control without oil and a reference with calcium propionate. Bread weight, volume, color and crumb texture were evaluated. The antifungal activity was tested through a shelf-life test of breads. Results showed that, generally, the addition of oils resulted in a decrease of dough consistency. WG showed the highest overall resemblance with the control concerning water absorption and kneading properties of the dough. Additionally, WG and TH were the only oils that could extend the shelf-life. WG caused a shelf-life increase of 3 days (+33%), TH 20 days (+100%). However, TH had a negative impact on dough rheology and yeast activity due to the high presence of thymol. In conclusion, it can be stated that WG showed the most promising combined technological and microbiological benefits in dough/bread.

This review addresses the recent advances of the application of essential oils (EOs) in in vitro systems and in bread systems for the reduction of fungal spoilage. Given the number of research articles concerning the use of EOs as potential antifungal food preservatives, it is generally accepted that they must be given further attention for use in specific food matrices. However, despite the numerous articles stating the antifungal effect of EOs, very few report the actual application in bread or other bakery products and the impact addition can have on dough and bread production, physico-chemical, microbiological and sensorial quality. Advances have been made in the area of food preservation, but further research is necessary to fully comprehend the mode of action and to establish actual food applications of EOs in the bread and bakery industry.

In this study, the incorporation of leek in wheat bread was explored. Green leek leaves were dried with two techniques to obtain leek powder after milling. The air-dried and freeze-dried powders were incorporated into wheat flour at five substitution levels (0, 0.5, 1, 1.5 and 2 g/100 g). The impact of leek powder on dough rheology, bread quality, sensory evaluation and mould-free shelf-life was investigated. Leek powder negatively impacted the mixing properties and significantly changed the viscoelastic properties of the wheat flour dough. At low levels, the dough was strengthened whereas at higher levels both dough resistance as extensibility decreased. Bread quality was also affected, resulting in lower bread volume and coarser crumb structure. The negative impact on dough and bread properties was more pronounced for freeze-dried powder. The result of the sensory study showed that wheat flour could be fortified by 1 g/100 g of leek powder without adverse effect on the consumer acceptability. Finally, the addition of leek powder did not impact the mould-free shelf-life of wheat bread.

The main objectives of this study were to investigate the antifungal activity of thyme essential oil (Thymus zygis) in-vitro and to validate its activity in par-baked wheat and sourdough bread (in-vivo) using the fungal strains Aspergillus niger and Penicillium paneum. The impact of thyme oil was evaluated in-vitro with the macro-dilution method with modified pH (4.8, 5.0, 5.5 & 6.0), aw (0.95 & 0.97) and temperature (22 & 30 °C) to mimic the conditions of wheat and sourdough par-baked bread stored at room temperature. Furthermore, the oil was applied in par-baked bread (0, 15 and 30 g sourdough/100 g dough). Challenge and shelf-life tests were performed to investigate the biopreservative potential of thyme oil in par-baked wheat and sourdough bread. Despite the promising in-vitro potential of thyme oil, no clear shelf-life extension was observed for par-baked bread which could be attributed to the oil. More research on food applications of essential oils is necessary to give the abundance of in-vitro studies industrial relevance. The use of sourdough, on the contrary, resulted in much more promising shelf-life extending properties. In both in-vitro as in-vivo assays, pH and aw showed no significant effect on fungal growth.

Sourdough is a very interesting natural preservation system to prolong mould free shelf-life of bread. Numerous studies have reported that the antifungal activity of sourdough is mainly correlated with the presence of lactic (LA) and acetic acid (AA), but very few information is available on the effect of undissociated acid concentrations in the aqueous phase of bread (C-HA; mmole/L). This study was conducted to provide additional information about the mode of action of the acids in sourdough bread, enabling a better shelf-life prediction. This study was divided into two parts. In part 1, three industrial biological sourdoughs were characterized (dough yield, pH, a(w), fermentation quotient, microbiota). During 7 weeks, a shelf-life test with natural flora was conducted with daily checks of visible mould growth (21 degrees C). In part 2, the effect of the acids present in the antifungal active sourdough breads was validated in chemically acidified wheat breads. Complete growth inhibition was observed in full-baked sourdough bread (30 g/100 g dough) containing Lactobacillus sanfranciscensis and Saccharomyces cerevisiae as dominant sourdough micro-organisms, whereas in control bread the shelf-life was limited to 4.4-9.2 days. These full-baked sourdough breads contained 36 mmole undissociated LA/L and 220 mmole undissociated AA/L. The data were used to make General Linear Regression models for shelf-life prediction and resulted in a fit of R-2 = 0.79 when expressing the shelf-life in function of C-HA,C- LA and C-HA,C-AA. In acidified breads, the role of lactic acid was not significant and only impacted shelf-life indirectly through acidification. No difference between antifungal activity of sourdough breads and chemically acidified bread with comparable C-HA,C- AA concentrations was observed. Shelf-life increased when 150-200 mmole undissociated AA/L aqueous phase in bread was present. To conclude, this study showed the importance of the undissociated acid fraction of acetic acid in relation to bread shelf-life, together with bread pH and moisture content.

Quinoa kernels are generally whole-milled due to their small kernel size. However, roller milling allows the separation of the starchy perisperm from the protein- and fat-rich bran fraction. Both fractions can be used for specific food applications. Studies have focused on roller milling of quinoa but information on tempering is rather limited. This study investigates the impact of different tempering conditions on roller milling of quinoa. Three types of commercially available quinoa seeds were roller-milled on small scale by a Brabender Quadrumat Junior. Two levels of tempering time (8 and 20 h) were combined with three levels of tempered moisture (13, 15 and 17%). Flour yield was recorded and the obtained flour was characterised by moisture, ash and protein content, flour colour index (FCI) and particle size distribution (PSD). An increase in tempered moisture reduced the flour yield, while a change in tempering time had no effect on two out of three samples. Flour composition depended on the combination of tempering conditions but increasing tempered moisture generally resulted in a better bran-perisperm separation. Differences in kernel properties were reflected in the PSD: small kernels created a coarser flour with higher ash and protein content.

Commercial shortenings and margarines are mainly produced via rapid cooling with scraped surface heat exchangers (SSHE) and therefore, controlling fat crystallization in the cooling process of these systems plays an important role. In this study, four batches of puff pastry shortening were produced from palm oil blends containing 25% and 50% anhydrous milk fat (AMF) using a bench-top SSHE. The outlet temperature of SSHE was investigated at 20 °C and 12 °C relating to the difference of crystallization temperature between palm oil and milk fat. Physico-chemical properties, crystal morphology and fat stability of these shortenings during storage at 5 °C were determined by various classical technologies including differential scanning calorimetry (DSC), polarized light microscopy (PLM), rheological and texture analyzer. Our results showed that fat blends crystallized at 12 °C had a stronger crystal network after production but the discrepancy of hardness diminished after the first storage week at 5 °C. Besides, the change of crystallization temperature did not affect significantly melting behavior as well as fat polymorphism of products. Upon storage, some big aggregates were detected in shortenings as a combined result of the recrystallization of palm fat crystals and the post-crystallization of milk fat triacylglycerols (TAGs).

EU regulation No. 1169/2011 states that foods that have been frozen and thawed before being sold, the name shall be accompanied by the designation ‘defrosted’. This requirement does not apply when defrosting has no negative impact on their safety and quality. Producers should be able to show that defrosting has no negative impact during the shelf-life. Therefore, the impact of temporary frozen storage on the quality and safety of industrially produced bakery products, including wholemeal bread, sandwich rolls, sponge cake and pie, was studied in comparison with non-frozen products. Total plate count, aw, texture analysis and sensory analysis were applied to assess microbial, physico-chemical quality and consumer acceptability of the products. All tests were performed before and after the defrosted shelf-life period. Freezing and defrosting of bakery products did not enhance microbial spoilage. All values remained under the maximal limit of microbial contamination, respectively 5 log CFU/g for bread products and 4 log CFU/g for sponge cake and pie. Texture analysis and aw showed only limited differences between fresh and defrosted products. Although a slight difference in texture was observed for sandwich rolls, sponge cake and pie through sensory trials, all products were found acceptable for consumption.

The aims of this study were (i) screening of antifungal activity of thyme essential oil on Penicillium paneum; (ii) development of growth/no-growth models (G/NG); and (iii) validation of the G/NG models by performing bread baking trials. The screening method was based on the measurement of fungal growth in a semi-solid medium through optical density. The combined influence of a

Objectives: To evaluate the long-term impact of zinc (Zn) supplementation on claw lesions, claw conformation, and histological and mechanical claw characteristics of sows housed in groups on rubber top layer or concrete floors during gestation. Materials and methods: Six groups of 21 ± 4 sows were allotted to group housing on different floor types for 80 days during gestation. Within each group, sows were randomly allocated to one of three diets supplementing a basal diet (46.6 and 128.9 mg Zn per kg during gestation and lactation, respectively) with 0, 50, or 100 mg Zn per kg. Claw lesion scoring, claw conformation, and horn growth and wear measurements were performed at days 50 and 140 of every cycle. Histological and mechanical characteristics were evaluated on claw samples of 36 sows after slaughter. Results: Dietary Zn supplementation affected heel horn erosion score (P = .01): sows supplemented with100 mg Zn per kg diet had better scores. Distances between dermal papillae of the sagittal heel horn were larger (P = .004). Heel height was lower for sows supplemented with 0 and 100 mg Zn per kg than for 50 mg per kg (P = .01). Horn growth and wear were lower for sows housed on rubber at day 50 (P < .001, both variables), but not at day 140. Dermal papillae distance was shorter for sows on rubber (P = .04). Implications: Unlike floor type and phase within the reproductive cycle, and under the conditions of this study, dietary zinc supplementation minimally influences claw quality.

The effect of sourdough amount and storage time on starch digestibility and estimated glycemic index (eGI) of tef bread was investigated. The rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) of 0-30% sourdough fresh tef breads ranged from 49 to 58, 16 to 29 and 20 to 26 g/100 g starch, respectively. Storage of tef breads up to 5 days decreased the RDS by more than 2-fold while SDS and RS increased by 2 and 3 fold, respectively. The eGI for fresh and stored breads ranged from 39 to 89. Addition of sourdough increased the eGI of fresh breads while no uniform pattern was seen in the stored breads. As the storage time increased, all the breads showed a decrease in eGI. In vivo study is necessary to further investigate the effect of sourdough on GI of tef bread.

Chemical composition, granular morphology and pasting properties of native starch extracted from tubers of Plectranthus edulis were analyzed. Starch was extracted from tubers of 6 accessions collected from 4 different areas in Ethiopia. Particle size analysis (PSA) and cryo-scanning electron microscope (cryo-SEM) imaging were used to examine the granular morphology and visualize the starch paste, respectively. Pasting properties, water absorption, and gelation capacity were compared. A wide range was found for the amylose (14.2% to 23.9%), calcium (216 to 599), potassium (131 to 878), and phosphorus (1337 to 2090) contents (parts per million per dry matter). PSA showed a bimodal distribution containing small spherical (14.6 μm) and large ellipse-shaped (190.4 μm) granules. Major differences were found for the pasting with peak viscosities differing from 3184 to 7312 mPa⋅s. Starch from accessions Chencha and Inuka showed a difference in packing density as clearly seen through cryo-SEM image at 75% of the peak viscosity (PV), and the granular integrity was mainly responsible for the significant difference in their PV and breakdown. Principal component analysis revealed 2 distinct groups: native starch extracted from accessions at the Wolayta zone (Inuka, Lofua, and Chenqoua) and other accessions (Jarmet, Arjo white, and Chencha). The study revealed the potential of P. edulis starch for its application in food industries. However, the inherent variation due to environmental conditions on physicochemical properties of the starch needs further investigation.Plectranthus edulis is cultivated in considerable amounts throughout Ethiopia, which makes it a valuable starch source. Due to its low tendency to retrograde, it could be applied in food industry as an equivalent for the current starch sources. Moreover, the low amylose content makes it preferable for an application in refrigerated foods as this unique quality trait prevents syneresis in end products during storage. Based on the significantly higher pasting temperature of the studied P. edulis starch extracts, it can form an alternative for potato starch, which is less suitable for its use in pasteurized foods.