New formulations of functional white sauces enriched with red sweet pepper: a rheological, microstructural and sensory study

Cooking methods determine chemical composition and functional properties of squash blossoms: A study of microstructural and bioaccessibility changes

This research aimed to evaluate the effect of different cooking methods (boiling, stir-frying, and steaming) on the microstructure, moisture, fat, protein, and glucose-derived carbohydrate contents, and the bioactive compounds (total carotenoids: CAR, total chlorophyll: CHLO, and total phenolic compounds: TPC) and antioxidant capacity (AC) of squash blossoms. Furthermore, we characterized polyphenolic compounds using HPLC and evaluated their bioaccessibility via in vitro digestions. Our results show that steaming and boiling do not affect moisture content. Only stir-frying decreased (p < 0.05) this parameter by 8 %. Additionally, the cooking methods increased (p < 0.05) protein and glucose-derived carbohydrate contents. All cooking methods changed the microstructure of the blossoms, probably due to the thermal and mechanical variations that result in moisture loss and degradation of cell wall components. As for the functional properties, boiling caused a greater loss of TPC (up to 96 %) and AC (up to 91 %). Stir-frying caused the greatest loss of CAR (up to 81 %) and CHLO (up to 84 %). The in vitro digestion assays showed changes in the bioaccessibility of CAR, CHLO, TPC, and AC in the cooked flowers compared to the fresh ones. Finally, kaempferol and gallic acid were the most resistant polyphenols to the cooking methods and in vitro digestion.

Crickets (Acheta domesticus) as Wheat Bread Ingredient: Influence on Bread Quality and Safety Characteristics

The aim of this study was to assess respondents' opinions on the choice of edible insects as a food, and to evaluate the influence of cricket flour (ECF) (10, 20, 30%) on the quality of wheat bread (WB). Whereas ECF is an additional source of acrylamide precursors, in order to reduce acrylamide formation in WB, fermentation of ECF with Lactiplantibacillus plantarum-No.122 was applied. It was established that 70.7% of the respondents had never eaten insects and more than 30% would not choose them. However, ECF was suitable substrate for fermentation (lactobacilli count 8.24 log₁₀CFU/g, pH-4.26). In addition, fermentation reduced the total biogenic amines content in ECF (by 13.1%). The highest specific volume showed WB, prepared with fermented ECF (10, 20, 30%). All the tested WB showed similar overall acceptability (on average, 7.9 points). However, the highest intensity of emotion "happy" was induced by the WB, prepared with fermented ECF. Most of the WB with non-treated and fermented ECF showed higher acrylamide concentration (except WB with 10% of fermented ECF), in comparison with the control. Finally, fermentation is recommended for ECF inclusion in the main WB formula because fermentation improves not only quality but also reduces acrylamide concentration in WB.

Technological Changes in Wheat-Based Breads Enriched with Hemp Seed Press Cakes and Hemp Seed Grit

Hemp and hemp seed press cake—a by-product of hemp oil production—are high-protein, gluten-free raw materials that are often used to enhance the nutritional value of breads. The addition of hemp materials, however, often negatively impacts the technological parameters of breads. Consequently, this study investigated whether and how much the addition of various by-products of hemp seed press cakes to wheat bread mixtures adversely affects the texture and colour profile. The texture profile and colour were determined using a texture analyser and tristimulus measurements. The particle size of raw materials was also measured. Principal component analysis was then used to visualise the correlation between all measured values as well as nutritional parameters. The results showed that the addition of only 1% of some hemp raw materials caused significant technological changes (p > 0.05). Hemp raw materials increased bread hardness and decreased elasticity. The colour of breads containing 1% hemp was also visibly darker than the reference bread. The addition of more hemp led to further darkening and the deterioration of the technological parameters of the products. Consequently, while various hemp materials have high nutritional value, a balance with sensory properties, e.g., textural and colour, has to be reached.

Microbial Communities and Physiochemical Properties of Four Distinctive Traditionally Fermented Vegetables from North China and Their Influence on Quality and Safety

The bacterial communities and physicochemical characteristics of four types of extremely distinctive traditionally fermented vegetables (pickled pepper (PP), pickled Brassica napobrassica (PBN), salted flowers of wild chives (SFWC), and pickled cucumber (PC)) were identified and compared from north China. Lactobacillus was the main bacterial genus in PP and PBN samples, with Oceanobacillus only being observed in PBN. The predominant genus in SFWC was Weissella, while in PC they were were Carnimonas and Salinivibrio. At the species level, Companilactobacillus ginsenosidimutans, Fructilactobacillus fructivorans, and Arcobacter marinus were abundant in PP and PBN. Levilactobacillus brevis and Companilactobacillus alimentarius were enriched in PP, and L. acetotolerans, Ligilactobacillus acidipiscis and Pediococcus parvulus were observed in PBN. Weissella cibaria and Kosakonia cowanii were abundant in SFWC. Moreover, tartaric acid was the most physicochemical factor influencing microbial composition, followed by malic acid, titratable acidity (TA), and lactic acid. Furthermore, functional analysis demonstrated that the most genes of the bacterial profiles correlated with carbohydrate metabolism. However, some foodborne pathogens were existed, such as Staphylococcus and Arcobacter marinus. The results of this study provide detailed insight into the relationship between the bacterial communities and physicochemical indices of fermented vegetables, and may improve the quality and safety of traditional Chinese fermented vegetables.

Interactions between Blackcurrant Polyphenols and Food Macronutrients in Model Systems: In Vitro Digestion Studies

Blackcurrant pomace, rich in fiber and polyphenols, can be used as added-value ingredient for food formulation. However, the bounding of polyphenols to pomace and the interactions that take place with food nutrients modify polyphenol bioaccessibility. This work studied the interactions between polyphenols and the main macronutrients in foods, and the changes that occurred during in vitro digestion, using model systems. Model systems were formulated with (i) water, (ii) wheat starch, (iii) olive oil, (iv) whey protein, and (v) a model combining all the ingredients. Polyphenols were added from two sources: as pomace and as a polyphenolic pomace extract. Interactions between polyphenols and macronutrients were studied using light microscopy; total phenolic content (TPC) and antioxidant capacity (AC) were determined before and after the in vitro digestion process. Lastly, the bioaccessibility of the samples was calculated. Polyphenols incorporated into the model systems as pomace increased their bioaccessibility if compared to polyphenols added as extract. For single-nutrient model systems formulated with pomace, the bioaccessibility was higher than when the system contained all the nutrients. Of all the components studied, the greatest effect on bioaccessibility was observed for proteins.

Changes in volatile compounds of fermented minced pepper during natural and inoculated fermentation process based on headspace-gas chromatography-ion mobility spectrometry

Changes in volatile compounds of fermented minced pepper (FMP) during natural fermentation (NF) and inoculated fermentation (IF) process were analyzed by the headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). A total of 53 volatile compounds were identified, including 12 esters, 17 aldehydes, 13 alcohols, four ketones, three furans, two acids, one pyrazine, and one ether. Generally, fermentation time played an important role in volatile compounds of FMP. It was found that most esters, aldehydes, and alcohols obviously decreased with the increase in fermentation time, including isoamyl hexanoate, methyl octanoate, gamma-butyrolactone, phenylacetaldehyde, methional, and E-2-hexenol. Only a few volatile compounds increased, especially for 2-methylbutanoic acid, 2-methylpropionic acid, linalool, ethanol, and ethyl acetate. However, no significant difference in volatile compounds was found between NF and IF samples at the same fermentation time. In addition, the fermentation process in all samples was well discriminated as three stages (0 days; 6 day; and 12, 18, and 24 days), and all volatile compounds were divided into two categories (increase and decrease) based on principal component analysis and heat map.

Optimizing High Pressure Processing Parameters to Produce Milkshakes Using Chokeberry Pomace

High hydrostatic pressure is a non-thermal treatment of great interest because of its importance for producing food with additional or enhanced benefits above their nutritional value. In the present study, the effect of high hydrostatic pressure processing parameters (200–500 MPa; 1–10 min) is investigated through response surface methodology (RSM) to optimize the treatment conditions, maximizing the phenol content and antioxidant capacity while minimizing microbiological survival, in milkshakes prepared with chokeberry pomace (2.5–10%). The measurement of fluorescence intensity of the samples was used as an indicator of total phenolic content and antioxidant capacity. The results showed that the intensity of the treatments had different effects on the milkshakes. The RSM described that the greatest retention of phenolic compounds and antioxidant capacity with minimum microbiological survival were found at 500 MPa for 10 min and 10% (w/v) chokeberry pomace. Therefore, this study offers the opportunity to develop microbiologically safe novel dairy products of high nutritional quality.

Composition and physicochemical properties of dried berry pomace

BACKGROUND

Berry pomace is a valuable but little used by-product of juice manufacturing. When processed to a stable fruit powder, the composition differs from that of the whole fruit. To facilitate application in foods, a detailed knowledge of its composition and physicochemical properties is essential.

RESULTS

Blackcurrant, redcurrant, chokeberry, rowanberry and gooseberry were selected for analysis. All pomace powders had a high fibre content (> 550 g kg^-1 ) and a fat content of up to 200 g kg^-1 . Despite identical milling conditions, the particle sizes of the pomace powders varied. This can be traced back to seed content and brittleness, which also becomes apparent with respect to surface characteristics. Blackcurrant pomace powder differed from other varieties in terms of its low water-binding capacity (3.2 g g^-1 ) and a moderate moisture uptake, whereas chokeberry pomace powder showed the highest polyphenol content and rowanberry pomace powder was rich in flavonols.

CONCLUSION

The results obtained in the present study provide a comprehensive overview of the properties of berry pomace powder and allow conclusions to be made regarding their applicability for use in complex food systems. © 2018 Society of Chemical Industry.