Food Technology and Biotechnology最新文献

An increasing amount of plastics is being used due to the growing population. Plastic waste pollution has become a major problem, especially in the marine environment, due to the increasing global demand for plastic materials. Bioplastics produced from waste in biorefineries offer a sustainable alternative to traditional plastics by recycling materials that are normally thrown away in the food, farming and manufacturing industries. This technology tackles both the plastic waste crisis and the inefficient use of biomass. By recycling biorefinery waste into bioplastics, the impact on the environment can be reduced, waste minimised and less fossil fuel consumed. Improving material qualities, reducing production costs and optimising the efficiency and scalability of these processes are all ongoing challenges. This review focuses on waste biorefineries for bioplastic synthesis as a sustainable approach to the circular bioeconomy. It also provides a better understanding of environmental sustainability, societal well-being and technological advances in the utilisation of various biorefineries as different substrates and methods for bioplastic synthesis.

Research background: The increasing environmental concerns due to fossil fuel consumption and industrial wastewater pollution necessitate sustainable solutions for bioenergy production and wastewater treatment. Palm oil mill effluent (POME), a high-strength industrial wastewater, poses significant environmental challenges. Microbial electrolysis cells (MEC) and microbial fuel cells (MFC) offer promising avenues for bioenergy recovery from such wastewaters.

Experimental approach: Dual-chamber H-type reactors equipped with proton exchange membranes were used to separately evaluate the performance of MEC and MFC in the production of bioenergy from POME. Hydrogen production and chemical oxygen demand (COD) removal in MECs were evaluated at different applied voltages and influent COD expressed as oxygen concentrations, while in MFCs the effect of external resistance on power output and COD reduction was investigated. Response surface methodology (RSM) was used to optimise these operational parameters for maximum bioenergy recovery and efficient wastewater treatment.

Results and conclusions: The results showed that the efficiency of hydrogen production and COD removal in MECs were maximised at low influent COD value and low voltage supply. The MEC effectively produced hydrogen and treated industrial wastewater, while the MFC successfully produced electricity and reduced COD. Field emission scanning electron microscopy confirmed the formation of biofilms on the electrodes, indicating active microbial communities involved in the production of bioenergy. A trade-off between power density and COD removal efficiency in MFCs was observed, with medium resistance values yielding maximum power output. The integration of MEC and MFC showed potential for treating high-strength industrial wastewater like POME, offering a greener and more energy-efficient approach.

Novelty and scientific contribution: This study demonstrates the potential feasibility of integrating MEC and MFC technologies for simultaneous bioenergy production and wastewater treatment from POME. It extends the knowledge in biochemical engineering by optimising operational conditions for improved bioenergy recovery and highlights the role of microbial communities in bioelectrochemical systems. The results form a basis for future research on sustainable bioenergy production and contribute to efforts towards environmental sustainability.

The cultivation of citrus fruits has increased significantly around the globe due to rising consumer demand. The citrus fruit processing industry produces approx. 110 to 120 million tonnes of citrus fruit waste worldwide every year. This in turn contributes to landfills and environmental pollution, and poses a risk to human health and the ecosystem. Proper recycling of citrus waste helps reduce pollution and also serves as a sustainable source for the production of different bio-based products. Abundant bioactive compounds in citrus waste offer immense economic value for the production of various useful products. Moreover, bioactive compounds found in citrus wastes have various biological properties, including antioxidant, anticancer, antimutagenic, antiplatelet, cardioprotective and antiviral activities. Instead of disposing of them directly, citrus wastes can be upcycled into various value-added products, including single-cell proteins, biopolymers, pectin, biofuel, biofertilizer and bioenergy. Citrus peels serve as a cost-effective reservoir of nutraceuticals and provide an affordable dietary option for the treatment of degenerative diseases. The citrus waste, which is used as a biofertilizer and is a rich source of phenolic compounds and carotenoids, helps to extend the shelf life of food. The aim is to maintain economic viability and sustainability with the help of recent innovations in the industry. This review discusses recent advances in the valorization of citrus fruit waste and presents innovative biotechnological approaches to extract valuable bioactive compounds such as limonene, flavonoids and pectin. These compounds are used in different sectors, from the food and pharmaceutical industries to bioenergy. Techniques such as microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) are characterized by high yields and energy efficiency. Techniques for sampling, pretreatment, extraction of phytochemicals, purification and identification of citrus fruit waste are also studied. Additionally, this review highlights the environmental benefits of waste valorization as part of a circular economy approach that contributes to both economic sustainability and pollution reduction.

Research background: Oxidative stress plays a crucial role in different diseases, including chronic hepatitis, cirrhosis and liver cancer, which are a major cause of mortality worldwide. Liver cell injury resulting from oxidative stress contributes to the development of these diseases. Garlic is known for its diverse physiological activities, and black garlic, produced by thermal ageing of raw garlic, has attracted attention due to its biological properties.

Experimental approach: This study investigates the hepatoprotective potential of black garlic prepared in an electric cooker. The study includes mass loss, browning index, free amino acids, free-reducing sugar content, total phenolic compounds and DPPH radical scavenging activity. Additionally, the sensory evaluation shows a preference for the black garlic sample over raw garlic. The study also investigates the activation of Nrf2-ARE pathway in HepG2-C8 cells and evaluates the protective effect against H₂O₂-induced damage.

Results and conclusions: The results indicate that black garlic lost mass, possibly due to water loss and the Maillard reaction, which led to an increase in the browning index and a decrease in free amino acids. However, the content of free reducing sugars increased. After 14 and 21 days, the total phenolic content of black garlic increased and its ability to scavenge DPPH radicals improved. Significant activation of the Nrf2-ARE pathway was observed in HepG2-C8 cells. Sensory evaluation showed a preference for the 14-day aged black garlic. The Nrf2 pathway can be effectively activated in HepG2 cells by a 14-day aged black garlic extract, resulting in protection against H₂O₂-induced damage.

Novelty and scientific contribution: Our research shows the significant effect of thermal ageing on black garlic and highlights its enhanced antioxidant properties. A simple approach has been developed to prepare black garlic that is more effective, healthier and can potentially be used to protect the liver and treat diseases related to oxidative stress.

Research background: Food safety is threatened by the contamination of fresh fruits and vegetables by pathogenic bacteria, among which the particularly widespread ones are coliform bacteria. Due to the continuous increase in the incidence of severe diseases caused by the consumption of fresh (tomato) fruits contaminated with Escherichia coli, antimicrobial postharvest measures are needed. The problem is that many active antimicrobial compounds have a weak and short-lasting effect and/or are not environmentally friendly. Recently, the antibacterial and antifungal activity of environmentally friendly agent phenylboronic acid (PBA), including on two tomato pathogens, has been reported.

Experimental approach: The aim of this study is to determine the antibacterial effect of PBA on E. coli and three enteropathogenic Enterobacterales, and to check its ability to serve as a bacterial decontaminant of fresh tomato fruits.

Results and conclusions: The minimum inhibitory concentration (MIC) of PBA against E. coli, as well as Shigella sonnei, Salmonella enteritidis and Yersinia enterocolitica was 1.0, 1.2, 1.0 and 0.8 mg/mL, respectively. In addition, we have shown that PBA has a bacteriostatic effect on E. coli at lower concentrations and a bactericidal effect at higher (>3.0 mg/mL) concentrations. Importantly, the study found that an E. coli strain resistant to seven commonly used antibiotics, as well as strains producing extended-spectrum beta-lactamases (ESBL), is as sensitive to PBA as the wild-type strain without any resistance, suggesting that the mechanism of action of PBA differs from that of all these antibiotics. Finally, we have shown that washing and incubating contaminated tomato fruits in PBA solution reduces the growth of E. coli washed from fresh tomato fruits in a concentration- (0.5-3.0 mg/mL) and time-dependent manner, while having no adverse effect on the tomato fruits.

Novelty and scientific contribution: This is the first report on the antibacterial effect of PBA on medically important bacteria E. coli, S. enteritidis, S. sonnei and Y. enterocolitica. Moreover, we show that PBA kills multidrug-resistant E. coli, including those producing ESBL, making it a promising agent against such bacteria. Finally, PBA is shown to be an effective decontaminant of E. coli on fresh tomato fruits.

Research background: Despite being a substantial and expanding market segment, there remain challenges concerning the shelf life of plant-based meat alternatives when synthetic preservatives are not used. Consequently, it is necessary to investigate the integration of natural extracts into these products to extend their shelf life.

Experimental approach: The total phenolic content, flavonoid content and antioxidant capacity of the powder of dried mangosteen peel extract was characterised. The fresh soy-based burgers were then formulated for six treatments including control (no antioxidant added), 10 mg butylated hydroxytoluene (BHT, a synthetic antioxidant), 10, 7.5, 5 and 2.5 mg dried extract and their proximate composition, physicochemical characteristics, protein and lipid oxidation, texture profile and sensory parameters during 10 days of storage were evaluated.

Results and conclusions: The addition of the extract reduced the moisture content and cooking loss. In addition, the burgers with the extract (5-10 mg/100 g) had remarkably lower values of peroxides, thiobarbituric acid reactive substances and carbonyls, indicating their higher stability against lipid and protein oxidation. These effects of the extract proved to be better than those of BHT. The burgers containing the extract also had improved texture in terms of springiness, chewiness and cohesiveness, resulting in higher texture scores. All treatments were accepted by consumers, with the average score of approx. 7 to 9 points. Therefore, the extract from mangosteen peels could be used as an excellent natural antioxidant substitution for synthetic ones currently used in food preservation.

Novelty and scientific contribution: The study fulfils a need for the growing plant-based meat alternatives with an extended shelf life of a healthier version by using a natural antioxidant extract from mangosteen peels instead of synthetic butylated hydroxytoluene. In addition, the study provides an assessment of product quality during storage and presents findings that could drive innovation in the use of natural preservatives in the food industry.

Research background: Cascara, the dried husk of coffee cherries, has attracted attention as a potential beverage due to its unique flavour profile and potential health benefits. Traditionally, cascara is prepared using hot brewing methods. However, recent interest in cold brewing methods has led to research on how temperature affects the functional properties of cascara beverages.

Experimental approach: Colour (CIE L*a*b*), total dissolved solids and titratable acidity were determined in cascara beverages prepared at 5, 10, 15 and 20 °C. The concentration of phenols and flavonoids, as well as antioxidant properties were evaluated using spectrophotometric methods. Caffeine, chlorogenic acid and melanoidins were quantified by HPLC. The mineral composition was determined using inductively coupled plasma mass spectrometry (ICP-MS). The results were compared with a hot-brewed cascara beverage.

Results and conclusions: Cold brewing resulted in significantly higher concentrations of total phenolic compounds, expressed as gallic acid equivalents (ranging from 309 to 354 mg/L), total flavonoids, expressed as quercetin equivalents (11.8-13.6 mg/L), and caffeine (123-136 mg/L) than the hot-brewed cascara beverage sample (p<0.05). Temperature had a noticeable effect on most variables, although the effect appeared to be random. In particular, concentrations of caffeine (p<0.01) and copper (p<0.001) were highest in beverages prepared at 20 °C and decreased with decreasing brewing temperature. Multivariate analysis showed that minerals (As, Co, Mn, Sn, Mg and Ca), hue and phenolic concentration contributed to the first principal component, which mainly differentiated the hot-brewed sample. Antioxidant-related variables, total titratable acidity and Se contributed most to the second principal component, which facilitated the separation of samples brewed at 5 °C.

Novelty and scientific contribution: To our knowledge, this is the first study to suggest that temperature affects the functional properties of cascara beverage produced by the cold brewing method. Experimental evidence supports the existence of a direct proportionality between caffeine and copper concentrations and brewing temperature.

Research background: Encapsulating lemuru fish protein hydrolysate is important to maintain its stability. However, optimal conditions for the encapsulation process of lemuru fish protein hydrolysate using statistical methods remain unexplored. This study aims to address this problem by optimizing the encapsulation conditions.

Experimental approach: Maltodextrin and gum Arabic were used as carrier agents, with mass per volume ratio ranging from 10 to 30 %, and spray dryer inlet temperatures between 90 and 100 °C. In this study, we analysed the main interactions of these variables using response surface methodology (RSM).

Results and conclusions: Our results show that mass per volume ratio of maltodextrin of 25 % and inlet temperature of 100 °C are the optimal conditions for the encapsulation of fish protein hydrolysate. The optimal conditions resulted in a high desirability index of 0.864, indicating an effective balance between yield, solubility and hygroscopicity. The actual results also fall well within the confidence interval of the predicted values, confirming the robustness of the model and the reliability of the predicted optimal encapsulation conditions. Encapsulated fish protein hydrolysate was compared with its non-encapsulated counterpart and characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and particle size analyser (PSA) to validate the results. The encapsulated fish protein hydrolysate showed distinct properties, such as the presence of functional groups from maltodextrin, interconnected particle and more homogeneous and narrower particle size distribution.

Novelty and scientific contribution: The encapsulation of lemuru fish protein hydrolysate using maltodextrin with mass per volume ratio of 25 % and inlet temperature 100 °C was successful in improving the properties of the protein hydrolysate. Further research should explore the functional properties of fish protein hydrolysate.