Food and Bioprocess Technology最新文献

Lanthanides were tested (Ce³⁺, Er³⁺, and Yb³⁺) as catalysts to produce lactic acid (LA) from the monosaccharides present in corn stover (glucose, xylose, and arabinose) resulting in ytterbium being the most active. A MW-heated system led to similar LA yield as a conventionally heated pressurized system. The maximum value of LA yield was 40% at 240 °C after 20 min of isothermal treatment regardless the starting monosaccharides, which allowed to propose a similar LA production route based on the products profile determined along time for the three monosaccharides. Temperature and time determined the product profile, observing furfural degradation at severity factors higher than 3.5, while values higher than 5.5 were needed to observe LA degradation. By increasing temperature, catalyst solubility decreased, increasing its presence in the solid residue after treatment. Xylan conversion to LA was similar as for xylose, but lower yield was obtained from microcrystalline cellulose. Corn stover presented more amorphous regions leading to higher hydrolysis yields of its cellulose fraction.

Controlled release of curcumin by a pH-sensitive carrier provides long-term preservation, which extends the shelf lives of fish. FTIR, XRD, ¹H NMR, zeta potential, swelling ratio, and TG analyses indicated that a pH-sensitive starch-based carrier with a narrow pH-sensitivity range (pH 6–7) was fabricated from the carboxymethyl starch grafted with methacrylic acid and then cross-linked with β-cyclodextrin to achieve dual functionality. FTIR, XRD, and fluorescence spectroscopy revealed that the mechanism by which curcumin was encapsulated in the starch-based carriers involved hydrophobic interactions and intermolecular hydrogen bonding. The encapsulated curcumin showed improved stability, higher antioxidant activity, antibacterial activity, and biocompatibility. The pH, TVB-N, TVC, and drip loss tests confirmed that the use of the carrier-curcumin complex at a concentration of 10 mg/mL for the preservation of yellow catfish extended the shelf life for 2–4 days during cold storage and improved the storage quality of the resulting fillets. This work provides a dual functionality strategy for constructing a pH-sensitive starch-based carrier to deliver curcumin and offers a promising choice for fish preservation.

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Selenylation modification is an effective way to improve the nutritional and health effects of tea polysaccharide, but the effects of different selenylation methods on the structure and efficacy of polysaccharides remain unclear. In this study, a series of chemically selenized tea polysaccharides (CSe-TPS, selenium content of 129.98 ~ 1454.99 µg/g) were prepared by Na₂SeO₃-HNO₃ method, which were promoted by heating (HCSe-TPS), ultrasound (UCSe-TPS), and pulse electric field (PCSe-TPS) treatments, respectively. These different CSe-TPSs were systematically compared with ordinary tea polysaccharides (Ord-TPS) and natural selenium-enriched tea polysaccharides (NSe-TPS) in aspect of molecular structure and biological functions. The results of molecular structure and apparent morphology showed that the particle size (p < 0.05) and the thermal stability of Ord-TPS were reduced after selenylation modification, while the absolute potential of polysaccharide was increased (p < 0.05), coupled with altered monosaccharide composition and changed apparent morphology. However, the main functional groups and the secondary structure of Ord-TPS did not change. The antioxidant activities of tea polysaccharides after selenylation were improved as well as their inhibitory effects on carbohydrate digestive enzymes (p < 0.05). The total antioxidant capacity of PCSe-TPS (selenium content of 240.66 ± 1.43µmol/g) was enhanced by 85.41% compared with Ord-TPS (selenium content of 129.80 ± 3.42 µmol/g), while its IC₅₀ values on inhibition of α-amylase (2.91 ± 0.18 mg/mL) and α-glucosidase (0.18 ± 0.01 mg/mL) were significantly lower than other tea polysaccharides (p < 0.05), which suggested best antioxidant and hypoglycemic activity. Moreover, tea polysaccharides with higher selenium content and smaller particle size showed better antioxidant and hypoglycemic activities. This research will provide new strategies for the application of tea polysaccharides.

The Azolla pinnata fern protein was enzymatically hydrolysed with Alcalase, Flavourzyme, and Papain at varying degrees of hydrolysis (10, 20, and 30%) to generate multi-biologically active protein hydrolysates. The extensively hydrolysed (30%) Alcalase-generated hydrolysate (AFPH-AE) was most active demonstrating antihypertensive (ACE inhibition), antidiabetic (DPP-IV, α-glucosidase, and α-amylase inhibition), and antioxidant (DPPH, ABTS, and FRAP) activities. AFPH-AE exhibited an uncompetitive inhibition mode against ACE and α-glucosidase, a mixed inhibition mode against α-amylase, and a noncompetitive inhibition mode against DPP-IV. This hydrolysate was highly stable under different food processing conditions including pH 5, 7, and 8, NaCl up to 150 mM, and a high temperature of 100 °C. The low molecular weight fraction (< 3 kDa) exhibited high biological activities, and a total of 15 low molecular weight bioactive peptides were identified. Molecular docking revealed that the peptide-enzyme interactions were mainly mediated via hydrogen bonds and hydrophobic interactions. Overall, these findings reveal the potential of AFPH-AE as a functional and/or nutraceutical ingredient with multifunctional antihypertensive, antidiabetic, and antioxidant effects.

Graphical Abstract

Β-glucans (BGs) are dietary fibers with human health benefits. Due to their emulsifying, thickening, and water-holding properties, they are frequently utilized in food formulations. Hull-less barley is one of the important sources of BGs. This research was performed to extract BGs from hull-less barley using microwave-assisted pressurized CO₂/H₂O (MW-PCO₂) extraction, a combination that had never been employed before. The MW-PCO₂ extraction conditions (temperature, time and water: barley flour ratio) were optimized using response surface methodology (RSM) with a Box-Behnken design for the maximum BG yield (%). Temperature of 47.74 °C, time of 19.92 min, and water: barley flour ratio of 10.10:1 (g/g) were found to be the optimum conditions for extraction with a BG yield of 62.43%. Additionally, MW-PCO₂ extraction was compared with conventional water extraction (CE) and BG extracts obtained by both methods were characterized. Chemical composition, molecular weight, thermal properties, water solubility, water holding capacity, surface morphology, and Fourier Transform Infrared Spectrum (FTIR) of the BG extracts were determined. MW-PCO₂ extraction gave higher BG yield and purity, molecular weight, and water holding capacity using less solvent in a shorter time. Furthermore, both extracts have similar morphological images, FTIR spectrum, and thermal properties. The results of this work demonstrate the potential of the MW-PCO₂ approach for extracting BGs from hull-less barley with improved selectivity and recovery, which can then be added to a variety of food and drug formulations.

This study investigates the production of pasta filata style cheese from a storable, frozen intermediate material. Homogenization (2–16 MPa, single-staged) of milk (fat/protein = 0.9) was used as a tool to decrease fat globule size and consequently fat losses. Plasticization was achieved by using a single-screw extruder set up with double-jacketed hot water cycle. Non-frozen and frozen cheese curd as well as the extruded pasta filata style cheese pre-treated with different homogenization pressure was analyzed regarding the thermo-rheological properties. Fat and protein gain/loss during extrusion was evaluated by analyzing fat in dry matter (FDM) and protein in dry matter (PDM) before and after extrusion. Homogenization of cheese milk leads to a reduction of tan δ for thereof produced raw cheese curd material as well as the extruded products. Freezing and extrusion counteract the reduction of tan δ. A homogenization pressure of 8 MPa is sufficient to prevent fat losses during extrusion while still maintaining plasticization of the product for fresh and frozen material, respectively. The FDM after extrusion is 0.8% higher for fresh material and 4.9% higher for frozen material, which means that the fat concentrates during extrusion due to water loss. Moreover, there is no loss of PDM for all samples, regardless of the homogenization pressure. A combination of homogenization pressure, freezing, and extrusion leads to a plasticizable product without losses of fat and protein. Hence, frozen cheese curd can be used as a storable intermediate.

Polyphenol compounds can modify myofibrillar proteins to improve the quality of fish and surimi. Nevertheless, research into the precise mechanisms of interaction between phenolic substances and sea bass myofibrillar proteins is lacking. This study aimed to explore the interaction mechanism between five phenolic compounds (caffeic acid (CFA), gallic acid (GA), chlorogenic acid (CHA), resveratrol (RES), and catechin (CAT)) with sea bass myofibrillar protein (MP). The results of UV–vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and fluorescence spectroscopy (namely, multi-spectroscopy) showed that all five phenolic compounds could spontaneously form new complexes with MP, with a binding molar ratio of 1:1. The interaction between CFA and MP is predominantly electrostatic, while the interaction between GA and MP is mainly hydrophobic. The rest of phenolic compounds and MP are mediated by hydrogen bonds and van der Waals forces. And molecular dynamics (MD) simulations indicated that CHA-myosin had the minimum root mean square deviation, while CFA-myosin had the smallest Rg value. In addition, the amino acid Lys-179 was the key residue for the interaction between five phenolic compounds and myosin. This study contributes to a better understanding of the interaction between phenolic compounds and sea bass MP, which could develop the processing of aquatic food products.