Food Technology and Biotechnology最新文献

Research background: The extensive cultivation of bananas (Musa sp.) is related to producing tons of residues, such as leaves, pseudostems and bracts (inflorescences). The banana bract is a commercially interesting residue due to its dietary fibre content and high antioxidant potential. With this in mind, this study evaluates the effects of administering banana bract flour in animal models fed a cafeteria diet.

Experimental approach: Thirty-two male rats were divided into 4 groups: (i) control diet, (ii) control diet with 10 % banana bract flour, (iii) hypercaloric diet, and (iv) hypercaloric diet with 10 % bract banana flour. The study was conducted for 12 weeks and included analysis of phenolic compounds, assessment of the antioxidant effect of banana bract flour, determination of serum biochemical parameters (glucose, total cholesterol, triglycerides, aspartate aminotransferase (AST), alanine transaminase (ALT), amylase, albumin, uric acid, creatine, total protein, and oral glucose), determination of faecal fat content, and histomorphological analysis of the liver, pancreas and adipose tissue. In addition, molecular parameters such as IL6, total and phosphorylated JNK, total and phosphorylated IKKβ, TNFα, TLR4 and HSP70 were determined.

Results and conclusions: The banana bract flour showed a high content of phenolic compounds and an antioxidant effect. The in vivo results suggest that the supplementation of a hypercaloric diet with banana bract flour prevented pathological damage by reducing total cholesterol and glucose amounts, which may imply a hepatoprotective effect of this supplement. Thus, using banana bract flour as a supplement can increase the consumption of fibre, antioxidants and bioactive compounds.

Novelty and scientific contribution: The development of flour from banana waste and its inclusion in the diet can prevent and/or help treat obesity. In addition, the use of banana bracts can help protect the environment, as they are considered a source of waste by the food industry.

Mead is a fermented alcoholic beverage that is made from honey diluted in water and commonly with the addition of other ingredients. The chemical characteristics of mead are closely related to the ingredients and additives that are used in its preparation, especially the type of honey, yeast strain and prefermentation nutrients, as well as herbs, spices and/or fruits. These additives can affect not only the fermentation process, in particular the yeast activity, the formation of metabolites and fermentation time, but also the bioactive potential of the mead, which mainly depends on phenolic compounds. Scientific studies have shown that the mead with added different plant species contains considerable amounts of different classes of polyphenols, which have important biological activities. Within this context, this review study seeks to investigate how different ingredients and additives can affect each of the stages of the preparation of mead, as well as its bioactive potential, in order to understand the effects on its chemical composition, and thus add greater commercial value to this beverage.

The meat and meat product industry has evolved according to the needs of the market. Consumers are increasingly seeking quality in food. Thus, the concern regarding the excessive use of additives such as preservatives and antioxidants has driven research towards natural, healthy and safe substitutes. Essential oils and plant extracts have been shown to be a good option for resolving this problem. They are completely natural with biological activity, which mainly includes prevention of oxidation and the proliferation of microorganisms, thus arousing the interest of the industry and consumers. This review will present studies published in the last five years regarding the potential of essential oils and plant extracts to act as preservatives and antioxidants in meat and meat products. The forms of application, innovations in the area, alternatives to the incorporation of essential oils and extracts in meat products, effects caused in food, and limitations of applications will be detailed and discussed.

Research background: While it is clear that SARS CoV-2 coronavirus is the primary respiratory virus, there are no entirely clarified ways of transmission. Foodborne transmission has remained an unexplained path. Therefore, the goals of this paper are to examine and present an assessment of the most appropriate of the four selected kits for RNA extraction for the testing and detection of SARS-CoV-2 on food packaging surfaces, food surfaces, and in food. This will enable to indicate the possibility of infection through contact or direct food consumption.

Experimental approach: Finding the best technique is vital as RNA extraction is one of the essential elements in detecting SARS-CoV-2. This was achieved through an experiment with four commercial kits following the original manufacturers' protocols, and with a modification of the original protocols that included the use of ethanol and isopropanol. The selected kit was used for RNA extraction from the swabs of packaging surfaces, food surface, and ready-to-eat food samples. The coronavirus was then identified using real-time reverse transcription-polymerase chain reaction (RT-PCR) assays to determine whether the SARS-CoV-2 virus or viral particles are present in the food chain with the overall purpose of demonstrating the possibility that food can contribute as a vehicle for the transmission of the virus.

Results and conclusions: The findings of this investigation made the most effective extraction kit and protocol stand out. The results of the applicability of the kit indicated a significant share of positive samples of viral SARS-CoV-2 virus particles on surfaces from the environment where infected persons with 'silent' COVID-19 infection, with mild symptoms or no symptoms, were present. However, according to the findings of the second part of the study, the virus was not detected on the examined samples of food packaging surfaces, food surfaces, and food.

Novelty and scientific contribution: The presented results distinguished one of the most suitable protocols for isolating RNA from environmental surface samples. The main contribution of the study is in the presentation of the results, that is, the examination of samples that are primarily related to the food chain, food packaging, food surfaces, and ready-to-eat food. The results of this study could also be helpful for further determination of the potential of food as a vector for the transmission of coronaviruses.

Research background: Ficus deltoidea (mistletoe fig) is a shrub well known among locals in Malaysia primarily for its treatment of toothaches, colds and wounds. The aim of this study is to determine the potential of leaves, sourced from three different varieties of F. deltoidea, to exhibit antioxidant activity, a reduction of lipid concentration, and protein expression in steatosis-induced liver cell lines.

Experimental approach: The leaves of three F. deltoidea varieties, namely Ficus deltoidea var. angustifolia, Ficus deltoidea var. trengganuensis and Ficus deltoidea var. kunstleri, were subjected to water extraction. The resulting crude extracts were fractionated using water and ethyl acetate. Palmitic acid was used to induce lipid accumulation (steatosis) in human liver (WRL68) cells, before all the samples were tested for their lipid-reducing activity. Several proteomic approaches were incorporated. The changes in protein expression were determined using 2-dimensional gel electrophoresis separation, whereas identification of our protein spots of interest was carried out via matrix-assisted laser desorption/ionization time-of-flight.

Results and conclusions: Ficus deltoidea var. kunstleri alone demonstrated the ability to reduce lipids at the highest tested concentration (200 µg/mL) and was, therefore, used for subsequent experiments. Treatment with Ficus deltoidea var. kunstleri was found to restore redox status by increasing superoxide dismutase and glutathione peroxidase amounts and decreasing malondialdehyde formation. Six proteins were successfully identified; these were heat shock protein beta-1 (HSPB1), proteasome subunit alpha type 1 (PSMA1), glutathione S-transferase omega 1 (GSTO1), peroxiredoxin-1 (PRDX1), histone H2B (HIST1H2BD) and ubiquitin c-terminal hydrolase L3 (UCHL3). Through bioinformatics analysis, it was found that these proteins were significantly involved in specific pathways such as oxidative stress (PRDX1 and GSTO1), protein homeostasis (HSPB1) and degradation (UCHL3 and PSMA1).

Novelty and scientific contribution: F. deltoidea pretreatment was shown to reduce lipid accumulation, thus improving the redox status and protein homeostasis. This suggests the role of F. deltoidea as a preventive mechanism in non-alcohol fatty liver disease.

Research background: Mayhaw jelly, made from mayhaw berries from the southern United States, is a popular food product that on processing produces a berry pomace waste. Little information is available in the literature about this waste or how to valorize it. This study investigated this food production waste and its possibilities for conversion to a biofuel.

Experimental approach: Dried mayhaw berry wastes were characterized with fiber analysis using the US National Renewable Energy Laboratory methods. After drying and grinding, hydrothermal carbonization was applied to the mayhaw berry wastes, the mayhaw waste without seeds, and mayhaw waste seeds. Fourier transform infrared spectroscopy (FTIR) was performed on mayhaw berry wastes, mayhaw waste without seeds, and mayhaw waste seeds. Calorimetry revealed the fuel value of each component of the waste and of the dried mayhaw berry wastes without any component separated. Friability testing on pellets of the biomass investigated their durability.

Results and conclusions: Fiber analysis indicated a high proportion of lignin compared to cellulose in the dried mayhaw waste. Hydrothermal carbonization did not enhance the fuel value of the seeds due to their tough outer coat that inhibited hydrothermal carbonization's high ionic-product water penetration. Other mayhaw berry waste samples had enhanced fuel value after treatment at 180 or 250 °C for 5 min, with a higher fuel value attained for 250 °C treatment. After hydrothermal carbonization, the wastes were easily pelletized into durable pellets. Fourier transform infrared spectroscopy characterization indicated raw seeds had high lignin content, as did the hydrothermal carbonization-treated mayhaw berry wastes.

Novelty and scientific contribution: Hydrothermal carbonization is a process not previously applied to mayhaw berry wastes. This study fills in the gaps of this waste biomass' potential to become a biofuel.

Research background: Sourdough is a spontaneously formed, complex microbial ecosystem of various lactic acid bacteria (LAB) and yeast which, by producing specific metabolites, determines the quality of the baked products. In order to design and control the sourdough with preferred nutritional characteristics, it is crucial that the LAB diversity of the product of interest be elucidated.

Experimental approach: Using the opportunities of next-generation sequencing (NGS) of the V1-V3 hypervariable gene region of 16S rRNA, we studied the microbial ecosystem of a whole grain sourdough made of Triticum monococcum, originating from Southwestern Bulgaria. Since the DNA extraction method is considered crucial for the accuracy of the sequencing results, as it can introduce significant differences in the examined microbiota, we used three different commercial kits for DNA isolation and analyzed their impact on the observed bacterial diversity.

Results and conclusions: All three DNA extraction kits provided bacterial DNA which passed quality control and was successfully sequenced on Illumina MiSeq platform. The results received from the different DNA protocols showed variations in the microbial profiles. Alpha diversity indices (ACE, Chao1, Shannon, and Simpson) were also different among the three groups of results. Nevertheless, a strong dominance of phylum Firmicutes, class Bacilli, order Lactobacillales, represented mostly by family Lactobacillaceae, genus Lactobacillus (relative abundance of 63.11-82.28%) and family Leuconostocaceae, genus Weissella (relative abundance of 3.67-36.31%) was observed. Lactiplantibacillus plantarum and Levilactobacillus brevis with relative abundance of 16.15-31.24% and 6.21-16.29% respectively, were the two dominant species identified in all three DNA isolates.

Novelty and scientific contribution: The presented results give insight into the taxonomic composition of bacterial community of a specific Bulgarian sourdough. Having in mind that the sourdough is a difficult matrix for DNA isolation on the one hand, and that there is no standardized DNA extraction protocol for this matrix on the other hand, this pilot study aims to give a small contribution to the future establishment and validation of such a protocol, which will allow accurate assessment of the specific microbiota of sourdough samples.

Acetic acid bacteria (AAB) are microorganisms widely distributed in nature. Although this group is involved in the spoilage of some foods, AAB are of great industrial interest, and their functionality is still poorly understood. AAB convert ethanol, sugars and polyols into various organic acids, aldehydes and ketones via oxidative fermentation. These metabolites are produced during a succession of biochemical reactions in various fermented foods and beverages, such as vinegar, kombucha, water kefir, lambic and cocoa. Furthermore, important products such as gluconic acid and ascorbic acid precursors can be produced industrially from their metabolism. The development of new AAB-fermented fruit drinks with healthy and functional properties is an interesting niche for research and the food industry to explore, as it can meet the needs of a wide range of consumers. Exopolysaccharides such as levan and bacterial cellulose have unique properties, but they need to be produced on a larger scale to expand their applications in this area. This work emphasizes the importance and applications of AAB during the fermentation of various foods, their role in the development of new beverages as well as numerous applications of levan and bacterial cellulose.