Osmotic dehydration kinetics of biofortified yellow-flesh cassava in contrast to white-flesh cassava ( Manihot esculenta ) Abstract In recent times, the cultivation, processing and consumption of biofortified yellow-flesh cassava is of significant interest to breeders and food processors due to its relatively high pro-vitamin-A content, compared to the conventional white-flesh cassava. In light of this, osmotic dehydration (OD) kinetics of a recently released biofortified yellow-flesh cassava was compared to that of a white-flesh cassava, using salt, sugar, and salt–sugar solutions at different temperatures (30, 45, 60 °C) and fixed cube/solution-ratio. Water loss (WL) and solids gain (SG) data were fitted by non-linear regression using four models (Page, Weibull, Azuara, and Peleg). Azuara model was most appropriate in describing OD kinetics for both cultivars. Azuara estimates for equilibrium WL and equilibrium SG, respectively, ranged between 0.101–0.120 and 0.049–0.094 g/g for salt solution, 0.158–0.212 g/g and 0.107–0.268 g/g for sugar solution and 0.234–0.306 g/g and 0.189–0.276 g/g for salt–sugar solution. The best conditions for OD of both cultivars by salt solution and sugar solution was at 60 °C and 45 °C, respectively, while that for salt–sugar solution varied with cultivar. Increasing temperature increased water loss and solids gain. Salt-OD conformed to Arrhenius temperature dependence of diffusivity, but sugar-OD and salt–sugar-OD did not. Micrographs reveal biofortified yellow-flesh cassava was more susceptible to cell wall collapse than white-flesh cassava. Extent of dehydration by OD agents ranked: salt–sugar > sugar > salt. Osmotic dehydration may be useful as a means of dehydration for cassava prior to drying, and is especially relevant for the carotenoids-rich biofortified yellow cassava.

Proteomic analysis of Saccharomyces cerevisiae to study the effects of red wine polyphenols on oxidative stress Abstract Understanding the molecular mechanisms underlying the “French paradox” has contributed to a growing interest in the investigation of the biological activity of red wine polyphenols (RWP). The main goal of this research is to provide valuable information on how RWP could exert their biological action at the cellular level. So, we report a proteomic analysis of S. cerevisiae exposed to both pro-oxidant (H2O2) and antioxidant (wine) agents. Cellular proteome analysis shows that RWP modify the level of certain proteins. Under both normal conditions (Wine treatment) and oxidative stress situations (Wine + H2O2 treatment), the proteins involved in the metabolism and biosynthesis of biomolecules were down-regulated, while one ribosomal protein was up-regulated, probably performing its ribosome-independent functions, and so contributing to the stress defense system. Considering this action mechanism, we suggest that RWP may be acting as mild pro-oxidants and, therefore, exerting a hormetic effect that leads to the strengthening of cells’ antioxidant capacity.

Sensory analysis and fatty acid profile of specialty coffees stored in different packages Abstract The conservation of the quality of special coffees depends on the storage conditions. Therefore, new technologies for the packaging of grains need to be studied. This work was carried out with the objective of evaluating the effect of different packages on the quality of the stored coffee. The free fatty acid profile, fat acidity and sensory characteristics of the grains were analyzed during storage. The coffees were stored for 12 months in 8 packaging types. Coffee stored in jute bags differed mainly due to the higher values of fat acidity and lower scores in sensory analysis. The high-barrier packages were more efficient in the storage of the coffee beans since they presented the lowest deterioration indicators, represented by the low values of fat acidity, free fatty acids and higher scores in the sensorial evaluation.

Microwave-assisted extraction of hempseed oil: studying and comparing of fatty acid composition, antioxidant activity, physiochemical and thermal properties with Soxhlet extraction Abstract This work aimed to investigate the effects of the microwave-assisted extraction (MAE) on the hempseed (Cannabis sativa L.) oil yield, oxidation stability, and antioxidant activity. Power (300, 450, and 600 W) and time (5, 10, and 15 min) were independent variables while oil extraction yield, peroxide value (PV), p-anisidine value (AV), TOTOX value (TV), and DPPH scavenging activity were considered as dependent ones. Optimization was conducted by response surface methodology where the optimum point was 450 W and 7.19 min. In this point, the extraction yield obtained 33.91% w/w and the oil showed acceptable oxidation quality (PV of 2.5 meq/kg, AV of 0.67, and TV of 5.67) and antioxidant activity with the IC50 value of 30.82 mg/mL. The Soxhlet extraction (SE) method was carried out to be compared with MAE. It showed relatively higher oil extraction yield (37.93% w/w) but lower oil oxidation stability with PV of 6.4 meq/kg, AV of 3.69, TV of 16.49, and higher amount of IC50 32.47 mg/mL which showed lower antioxidant activity. Any significant difference between fatty acid compositions was not observed with the dominant amounts of linoleic acid and α-linolenic acid. Also, the tocopherol contents and thermal properties were studied by HPLC and DSC, respectively. MAE showed higher total tocopherol content (929.67 mg/kg) than SE (832.61 mg/kg) and γ-tocopherol was dominant. Moreover, DSC analysis showed that both profiles (crystallization and melting transitions) are likely influenced mostly by the triglyceride compositions and crystals structure.

Amelioration in gliadin antigenicity and maintenance of viscoelastic properties of wheat ( Triticum aestivum L.) cultivars with mixed probiotic fermentation Abstract Sourdough fermentation of twenty wheat cultivars was carried out using mixed probiotic culture (Lactobacillus acidophilus UNI, Lactobacillus brevis LR/5 and Lactobacillus plantarum ATCC 8014). The gliadin antigenicity was expressed in terms of its content in twenty different wheat cultivars. The gliadin proteins were characterized by SDS-PAGE and structural changes analyzed on FTIR spectrophotometer. Moreover, changes in the viscoelastic character of fermented and non-fermented dough were studied by rheometry. The results showed a remarkable reduction in antigenicity by 60% (average) in all wheat cultivars on sourdough fermentation. This reduction may be due to the synergistic effect of protease secretion by mixed lactobacilli, responsible for gliadin degradation. These changes in gliadins by mixed culture proteolysis were confirmed on SDS-PAGE on observing new gliadin-derived low molecular weight peptides. The results were further validated by FTIR spectroscopy where structural changes of gliadins were analyzed in the fermented dough. The rheological data indicated a higher storage modulus (G′) compared to loss modulus (G″) in both control and fermented flour of all wheat cultivars, however, with a lower efficacy in sourdoughs. The present study thus establishes that mixed culture sourdough fermentation decreases the antigenic potential of gliadins without any change in the rheology and thereby maintaining the baking or viscoelastic properties of the wheat flour.

Extraction of bioactive ingredients from fruiting bodies of Antrodia cinnamomea assisted by high hydrostatic pressure Abstract The aim of this study was to use high hydrostatic pressure treatment to enhance the extraction efficiency of the active components from the fruiting bodies of Antrodia cinnamomea, and compare with those obtained by shake and ultrasonic extraction methods. The conditions of high pressure extraction (HPE) at 600 MPa, a liquid/solid ratio of 40:1, and 3 min of treatment yielded triterpenoids and adenosine concentrations of 410.41 mg/100 mL and 0.47 mg/100 mL, respectively, which did not differ significantly from those with the two other treatments—shake extraction at 180 rpm for 8 h and ultrasonic extraction at 50 Hz for 60 min. The HPE extracts significantly attenuated reactive oxygen species, nitric oxide and prostaglandin E2 production in lipopolysaccharide-stimulated RAW 264.7 cells than shake extracts did. SEM micrographs revealed that high-pressure caused physical morphological damage to the mycelium of fruiting bodies, such as distortion and disruption of mycelial cells, and increased the mass-transfer effectiveness of the solvent and solute. HPE can be employed as an efficient extraction technique for production of bioactive ingredients that might have a potential application in food and related industries.

Recommended storage temperature for green tea based on sensory quality Abstract This study aimed to evaluate the effect of storage temperature on the alteration of the sensory quality of tea. Huangshan Maofeng tea was stored at − 80 °C, − 20 °C, 4 °C, or room temperature for up to 150 days. The physicochemical parameters, taste-related components, appearance color, volatile compounds and sensory quality of tea were analyzed and compared. Results showed that storing tea at − 80 °C and − 20 °C effectively preserved the physicochemical parameters, taste-related compounds and appearance color in tea. Multivariate statistical analysis (PCA and OPLS-DA) indicated that tea stored at − 80 °C exhibited a similar volatiles composition as fresh tea based on gas chromatography–mass spectrometry, whereas the composition of volatiles was significantly altered in tea stored at 4 °C after 100 days of storage. Sensory evaluation illustrated that tea stored at − 80 °C and − 20 °C remained the freshness regarding leaves appearance and tea infusion color, taste and aroma, whereas an obvious decrease on the tea freshness was found in tea stored at 4 °C and room temperature. These findings indicated that storage temperature played a vital role in altering the aromatic and sensory quality of Huangshan Maofeng tea and the recommended tea storage temperature was − 80 °C or − 20 °C.

Effect of wooden breast condition on quality traits of emulsified chicken patties during frozen storage Abstract Wooden breast (WB) is a recent abnormality characterized by tougher consistency in raw broiler breast fillets. This myopathy has been associated with negative alterations in chicken meat quality. The aim of this study was to evaluate the influence of WB condition on quality parameters of emulsified chicken patties (ECP) during frozen storage. Three formulations of ECP were processed, namely, PN (100% normal breast), PW (100% WB) and PNW (50%:50% normal:WB). ECP were frozen stored during 90 days and assessed by physicochemical and sensory analysis. Variations in redness were less pronounced in PW along the storage. TBARS were higher in PW and PNW until 30 days of storage compared to PN samples. Incorporation of WB into ECP formulation resulted in reduced peroxide-value, p-anisidine index and carbonyl content at the end of storage. Despite the different alterations in lipid and protein oxidation markers along storage time, results did not influence sensory acceptability, since no effect of wooden breast condition and storage time in odor and color liking was found in our experiment. This study elucidates for the first time that the use of WB meat for the elaboration of ECP is a feasible strategy to minimize economic losses for the poultry industry.

Lactobacillus -fermented sourdoughs improve the quality of gluten-free bread made from pearl millet flour Abstract The study investigated the effect of sourdough made from combinations of four Lactobacillus spp. on the physicochemical properties, consumer acceptability, and shelf life of bread made from pearl millet flour. Fermentation based on both single and multiple species reduced the pH of the dough and increased its titratable acidity and H2O2 content. The addition of sourdough increased the elasticity and reduced the stiffness of the pearl millet dough. Sourdough fermented with L. brevis had the greatest effect on loaf height, specific volume, porosity, and moisture content. During storage, the moisture content of the bread crumb decreased, but that of their crust increased. Sourdough-based loaves retained their moisture better than conventional loaves and the sourdough suppressed the development of mold for a longer period. An organoleptic assessment showed that the sourdough-based bread was more palatable than either conventional or chemically acidified ones. The tissue softness, chewiness, and flavor of the pearl millet bread decreased during storage. The use of sourdough based on either L. brevis, L. paralimentarius, or L. brevis + L. paralimentarius is recommended to produce high-quality pearl millet-based bread.

Shelf life prediction and food safety risk assessment of an innovative whole soybean curd based on predictive models Abstract The aim of the present study is to predict the shelf life and evaluate the risk profile of an innovative whole soybean curd (WSC). Two main spoilage strains were isolated from spoiled WSC and identified as B. subtilis and B. cereus. The origin analysis confirmed that B. subtilis and B. cereus originated from soybean materials and survived in soybean curd. For microbial contamination analysis, thermotolerant coliforms, E. coli and S. aureus were not detected in soybean curd. The predicted shelf life of WSC and okara-filtered curd that was stored at 10 °C were 141.95 h (5.91 d) and 206.25 h (8.59 d), respectively. Moreover, the models applied in this study exhibited great fitting goodness and the predicted growth parameters were fail-safe. To conclude, introduction of okara into soybean curd reinforced the initial contamination level but didn’t significantly increase the risk profile of WSC.