Food Technology and Biotechnology最新文献

Research background: Nowadays, there is a growing interest in active packaging with the addition of natural extracts due to safety concerns and consumer preferences. Physalis angulata is a medicinal and edible species of the Solanaceae family and is rich in phenolic compounds. Phenolic compounds, the secondary metabolites, are synthesised and stored in all plant tissues. They can be used as plasticizers or fillers to improve the interfacial interaction between the two biopolymers and prevent the transfer of moisture and gas from the food product and extend the shelf life to some degree.

Experimental approach: The effect of a three-layer (P/G/B) film based on polylactic acid (P), gelatine (G) and polybutylene adipate-co-terephthalate (B) incorporated or not with Physalis leaf extract (PLE) on the quality changes of fish meat powder (sample) stored at 27-30 °C (30 days) was investigated in comparison with control (uncovered), polyethylene (PE), polylactic acid, polybutylene adipate-co-terephthalate and gelatine films. The samples were sealed in a cylindrical bottle covered with the prepared films. The storage properties such as moisture content, pH, peroxide value (PV), thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), changes in colour, sensory properties and volatile compounds of samples packed with the developed films were analysed.

Results and conclusions: The moisture content was lower in the sample covered with the P/G/B-PLE-7 % film throughout the storage period. However, the sample covered with PE film had the highest PV (p<0.05). TBARS, TVB-N and volatile compounds decreased in the sample covered with P/G/B-PLE-7 % on day 30 of storage. The incorporation of Physalis leaf extract into the three-layer film improved the properties of the film and extended the shelf life of fish meat powder. Thus, the addition of Physalis leaf extract to the three-layer film could serve as a biodegradable active packaging and be a promising substitute for commercial plastic films.

Novelty and scientific contribution: This is the first report on the study of chemical changes of fish meat powder covered with a three-layer (P/G/B) film incorporated with Physalis leaf extract. This will lead to a better understanding of the role of the three-layer (P/G/B) film containing Physalis leaf extract on the extension of shelf life of fish meat powder.

Research background: Glucomannan is a polysaccharide compound used widely in food and pharmaceutical industries. The tuber of Amorphophallus muelleri Blume is called porang in Indonesia. Ethanol extraction is commonly used to extract glucomannan from porang flour; however, the method has some limitations. Glucomannan obtained by ethanol extraction has a higher protein content than standard glucomannan. In this work, the salting-out effect of the salts of the aqueous two-phase system was investigated for the extraction of glucomannan. In this way, the protein can be removed from the glucomannan flour, thus increasing the purity of the obtained glucomannan.

Experimental approach: A novel glucomannan extraction method using an aqueous two-phase system (ATPS) consisting of salt and ethanol was investigated. The Na₂HPO₄ and K₂HPO₄ salts at 3 different mass fractions (1, 2 and 3 %) mixed with 40 % ethanol in a 1:1 volume ratio were used to prepare the ATPS. The efficiency of ATPS in the extraction of glucomannan was based on the phase separation and better properties of glucomannan, including proximate composition, colour, thermal properties and surface morphology were obtained. Statistical analysis was performed to test the significant differences between the mean values of each treatment. The statistical significance level was set at p=0.05.

Results and conclusions: The results showed that the aqueous two-phase system was able to separate a solution of porang flour into three layers, namely bottom (F1), middle (F2) and top (F3) layer. The bottom (F1) and middle (F2) layers were rich in glucomannan and starch, respectively, while the top layer (F3) consisted of an ethanol-soluble compound. The salts affected the yield of glucomannan and the properties of the obtained glucomannan, including colour, impurities (protein and ash), thermal properties, molecular mass and surface morphology. Increasing salt mass fraction decreased the yield of glucomannan but increased the yield of other components. ATPS reduced the protein content and increased the lightness of the glucomannan. The glucomannan obtained with ATPS had a higher thermal stability than the control.

Novelty and scientific contribution: Salting-out ability of the salt of the aqueous two-phase system is commonly used in protein precipitation and isolation. However, there was no report found on the application of ATPS for the isolation of glucomannan. This study has shown that the ATPS (ethanol/Na₂HPO₄ and ethanol/K₂HPO₄) is a potential new extraction method for glucomannan extraction.

Research background: In India, widespread dietary deficiency in calcium and vitamin D is a significant public health concern. Over the past five decades, evidence has shown a decline in dietary calcium intake in rural, tribal and urban populations. This persistent deficiency poses a serious risk to bone health and contributes to the development of rickets, osteoporosis and osteopenia, as well as potential disturbances in metabolic rates and physiological functions. A key factor in this decline appears to be the reduced consumption of calcium-rich dairy products. As a result, research is exploring alternative, highly bioavailable sources of calcium, such as those derived from fish bone waste. The potential of nano-calcium supplements to improve absorption and bone density compared to traditional supplements is an area of active investigation.

Experimental approach: Nano-calcium powder was synthesised from the bones of two commercial fish species, Daysciaena albida and Otolithes ruber, ethically sourced from the Kerala coast following relevant regulations. Alkali extraction method was used and the resulting nano-calcium powder was characterized by various physiological and chemical analyses.

Results and conclusions: The yield percentage of two samples was different. Notably, both samples had different colour properties, proximate composition and results of scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The nano-calcium from D. albida also contains slightly more calcium and phosphorus than that from O. ruber. The nanoparticles of the calcium from D. albida (d=153.8 nm) were also smaller than the nanoparticles of the calcium from O. ruber (d=337.1 nm). Interestingly, further analyses using techniques such as Fourier transform infrared spectroscopy (FTIR), zeta potential, thermogravimetric analysis (TGA) and X-ray diffraction (XRD) showed significant similarity between the nano-calcium samples from D. albida and O. ruber, despite the initial differences in yield, composition and particle size. This result suggests that the choice of fish species significantly affects the yield, composition and properties of the synthesised nano-calcium powder with D. albida appearing to be a more favorable source, but both products can exhibit similar functionality and warrant further investigation.

Novelty and scientific contribution: This is the first report on the extraction and characterization of biogenic nano-calcium from two commercial fish, Daysciaena albida and Otolithes ruber from the Malabar Coast, India. The extracted nano-calcium powders from these two fish are a good source of calcium and help overcome calcium-related disorders.

Research background: Hydrodistillation is a convenient and economical method to extract essential oils, but this technique has been abandoned due to limited extraction rates. Comparison to conventional hydrodistillation, maceration-mediated hydrodistillation could increase mass transfer and provide better control over the extraction thermodynamics, thereby preserving the aroma constituents and their antioxidant activities. The present study describes a useful and innovative modification of conventional hydrodistillation by introducing a macerating agent Triton X-100 and NaCl as an electrolyte to accelerate mass transfer for better extraction of caryophyllene-rich essential oil from sea buckthorn berries.

Experimental approach: The parameters of maceration-mediated hydrodistillation, including the mass fraction of macerating agent, electrolyte concentration and extraction time, were investigated within a wide range of 1-10 %, 1-10 g/100 mL and 3-8 h, respectively, to increase the oil yield (g/100 g). The parameters were optimized according to the desirability approach using response surface methodology. The antioxidant activity of the essential oil obtained under optimal conditions was measured using in vitro antioxidant assays and its aroma profile using gas chromatography with mass spectrometery (GC-MS).

Results and conclusions: The optimized parameters for the modified hydrodistillation were observed at 4.22 mL Triton X-100 and 4.03 g NaCl for 5.61 h of extraction time with the essential oil yield of (3.2±0.1) % compared to 2.1 % obtained with conventional hydrodistillation. The essential oil produced by the assisted hydrodistillation was rich in (-)-β-caryophyllene (37.2 %) with good antioxidant activities in terms of free radical scavenging capacity (84.2 %), inhibition of linoleic acid peroxidation (68.2 %) and antioxidant capacity expressed in Trolox equivalents (168 µmol/mL).

Novelty and scientific contribution: Triton X-100 can disrupt the cell membrane to release the bioactive compounds, while the NaCl reduces the solubility of the non-polar components of the essential oil in the aqueous phase, which can ultimately improve the extraction yield. The proposed approach can be used with minor modifications with the existing hydrodistillation setups and it seems to be more economical for the extraction of sea buckthorn essential oil without compromising its antioxidant potential or its valuable aroma compounds on an industrial scale.

Research background: Dragon fruit (Hylocereus spp.) has been known to be a rich source of bioactive compounds, such as anthocyanins, betacyanin, betaxanthin and other phenolic substances, and it has a nutritional profile suitable to produce wine with functional properties. The aim of this study is to characterize the wine fermentation from red dragon fruit juice by a newly identified yeast strain.

Experimental approach: Yeast strains from banh men, a Vietnamese traditional alcoholic fermentation starter, were screened for ethanol production using thermally pretreated red dragon fruit juice. The most potent candidate was identified by the DNA sequencing method and subjected to an optimization study using a one-factor-at-a-time approach to optimize the conditions for red dragon fruit wine fermentation.

Results and conclusions: Results showed that thermal pretreatment of the red dragon fruit juice at 70 °C for 10 min resulted in a higher amount of phenols and antioxidants than at other pretreatment temperatures. Among the four isolates, M7 was the strongest alcohol fermenter, which was then identified as Saccharomyces cerevisiae using a DNA sequencing method. The optimal conditions for wine fermentation from red dragon fruit juice by S. cerevisiae M7 included a pitching rate of 10⁸ CFU/mL, an initial sucrose content of 18 % (m/V), an initial pH=4.5, fermentation temperature of 30 °C and a fermentation time of 6 days. Under these conditions, the wine fermented by S. cerevisiae M7 had an ethanol volume fraction of (12.1±0.2) %, the concentration of total phenolics expressed as gallic acid equivalents (37.8±0.4), anthocyanins expressed as cyanidin 3-glucoside equivalents (11.2±0.3), betacyanin (65.2±0.8) and betaxanthin (60.5±1.3) mg/L and antioxidant activity measured by DPPH scavenging capacity of (65.4±0.4) %.

Novelty and scientific contribution: This study used a novel yeast strain Saccharomyces cerevisiae M7 for fermentation. In addition, the results of the study provide new data such as the optimal parameters and the accumulation of bioactive compounds (phenols, anthocyanins and betalains) related to the fermentation of red dragon fruit wine.

Nitrite and nitrate salts are preservatives that act as antimicrobial (bacteriostatic and bactericidal activity) and antioxidant agents in the processing of meat products and confer sensory properties to meat (by creating and preserving colours and flavours). Nitrite is mainly used as a preservative to prevent the growth of Clostridium botulinum and the production of its toxins. However, nitrite and nitrate are also associated with the production of N-nitroso compounds, such as carcinogenic N-nitrosamines, which can have adverse health effects. Therefore, the health risks of these preservatives must be weighed against the need to prevent foodborne pathogens, especially spores of C. botulinum, from infecting food. In this review, we discuss the advantages and disadvantages of using nonthermal technologies as a strategy to partially or totally replace nitrite in meat products, particularly regarding antimicrobial efficacy and N-nitrosamine formation. Methods such as high-pressure processing, pulsed electric fields and cold plasma have been studied for these purposes, but these technologies can alter the sensory properties and stability of foods. Nevertheless, irradiation at lower doses has great potential as a tool for reformulation of cured meat products. It contributes to the reduction of the residual nitrite and consequently to the production of N-nitrosamines while ensuring microbiological safety without significant changes in the product quality.

Research background: Green extraction technologies, such as microwave-assisted extraction, have been used to replace conventional methods of isolating essential oils from plants. In this study, the essential oil was extracted from the Lippia adoensis variety koseret using the advanced method of microwave-assisted hydrodistillation. The main objective was to investigate the effect of irradiation time, microwave power and particle size on the yield and chemical composition of the essential oil extracted from leaves dried in an oven at 50 °C and room temperature.

Experimental approach: The drying experiments were initially carried out by oven drying and drying at room temperature until 10 % of moisture was achieved. Several essential oils were then extracted from the oven-dried samples for a preliminary study, followed by optimisation of the essential oil yield. The Box-Behnken design with response surface methodology was used to optimise the process and effectively analyse the influence and interaction of the factors on the essential oil yield. The chemical composition and functional groups of the essential oil from both samples were then analysed.

Results and conclusions: The micrographs of the oven-dried leaves showed damage to the glandular trichomes. The analysis of variance showed significant linear, quadratic and interaction effects of particle size and time, as well as of microwave power and time on essential oil yield. The optimal conditions were: 30 min irradiation time, 550 W microwave power and a particle size of 0.5-0.7 mm, resulting in essential oil yields of (0.49±0.01) % from the oven-dried leaves and (0.40±0.01) % from the room-dried leaves, which accounted for (85.1±0.8) and (87.2±0.7) % of the oils, respectively, with linalool being the predominant component. Fourier-transform infrared spectra showed the presence of hydroxyl functional groups, confirming the chemical composition results.

Novelty and scientific contribution: The results showed the effect of drying methods and microwave-assisted process parameters on the quantity of the produced essential oils. The essential oil yield obtained by the innovative microwave-assisted hydrodistillation results in an efficient process and product quality that can be a very useful ingredient for the food and pharmaceutical industry.

Research background: Chickpea is a very good source of protein for the development of protein-enriched plant-based ingredients. Chickpea protein isolates are primarily obtained by wet extraction methods such as alkaline or salt extraction. The energy input required for the production of chickpea protein isolates can have an impact on both the environment and processing, thus affecting nutritional quality and human health. Therefore, further research is needed to develop mild processing techniques for the isolation of chickpea proteins.

Experimental approach: In this study, with the aim of developing a more efficient and effective method, chickpea proteins were isolated by ultrasound-assisted extraction and the process parameters were optimised using the Box-Behnken design.

Results and conclusions: Under the optimal extraction conditions (solid/solvent ratio 13.42 g/100 mL, pH=8.8, extraction time t=10 min, ultrasound amplitude 70 %), the highest extraction yield was obtained, 66.1 % with ultrasound-assisted extraction and 55.1 % with the conventional alkaline method. When comparing the ultrasound-assisted method with the conventional alkaline method, it was found that a higher protein isolation yield was obtained with a 6-fold shorter processing time and a 29-fold lower energy consumption. Moreover, it was found that the water/oil absorption properties of the protein isolate obtained by the ultrasound-assisted method increased and its foaming properties improved.

Novelty and scientific contribution: This research presents a feasible ultrasound-assisted extraction technique for the isolation of chickpea protein, which can then be used as a versatile ingredient in the food industry.

Research background: Porang (Amorphophallus muelleri Blume) contains a high amount of starch, glucomannan and Ca-oxalate. Soaking porang tuber in acid (citric acid) and salt (sodium chloride) solutions affects the Ca-oxalate content, functional, rheological and thermal properties of porang flour. The aim of this study is to thoroughly investigate the effect of soaking treatments in acid and salt solutions at different temperatures on the physicochemical, rheological and thermal properties, functional groups, molecular mass and morphology of porang flour.

Experimental approach: Soaking treatments in acid and salt solutions at different temperatures affect the properties of porang flour. This research investigated the effect of soaking porang slices in citric acid (5 %) and sodium chloride (8 %) solutions at different soaking temperatures (25, 55 and 85 °C for 1 h) on the properties of the resulting porang flour.

Results and conclusions: The results of this study showed that all treatments successfully reduced the Ca-oxalate mass fraction in porang flour. The acid treatments reduced the glucomannan content more than the salt treatments. Soaking in acid solutions also decreased viscosity, molecular mass and thermal stability of porang flour. When the soaking temperature was increased, the Ca-oxalate mass fraction, molecular mass, viscosity and thermal stability of the porang flour decreased. The acid and salt treatments did not change the FTIR patterns. The morphological analysis showed that the acid and salt treatments resulted in particles with rough surface and short crystal needles of Ca-oxalate. Soaking the porang slices in salt solution at a temperature of 55 °C was the most effective treatment to reduce the Ca-oxalate content of porang flour while retaining its other quality parameters.

Novelty and scientific contribution: The results of this study provided a comprehensive understanding of the effect of soaking porang slices in acid and salt solutions on the properties of the obtained porang flour. They can be used as scientific evidence on how to treat the porang slices to obtain the best quality of porang flour.

Research background: The use of plant extracts in the biological control of fungal plant diseases can reduce the use of fungicides and residues in food by effectively suppressing mycotoxigenic microorganisms. The focus of interest is therefore finding plant extracts that have antifungal properties and are not toxic to organisms, so that they can be used for the biological control of economically important phytopathogenic fungi such as Fusarium. Species of the genus Fusarium are considered economically important pathogenic fungi of numerous agricultural crops, which not only cause significant losses but also produce mycotoxins that reach consumers through food. One of the most important species of this genus is the species Fusarium sporotrichioides, which causes economically significant damage to a large number of agricultural crops.

Experimental approach: In this laboratory study, the influence of aqueous cinnamon bark extract on the growth and development of the toxicogenic fungus F. sporotrichioides was investigated using the poisoned food technique. For the study, the aqueous extract of cinnamon bark was obtained by ultrasound-assisted extraction and the content of antifungal compounds was detected by phytochemical tests.

Results and conclusions: The research results confirm a significant inhibition of the growth of the pathogen when grown individually on a potato-dextrose agar (PDA) medium with 3 and 5 % extract. The antifungal effect of the extract was demonstrated by microscopic analysis of the pathogen, which showed significant deformation of hyphae and a change in the mycelium colour after seven days of growth on medium with 5 % extract, resulting in a threefold higher inhibition of pathogen growth than growth on medium with 3 % extract. The microscopic changes also show a reduction in pathogen sporulation and a possible reduction in mycotoxin production. Phytochemical tests confirmed the presence of antifungal compounds in the extract.

Novelty and scientific contribution: Based on the obtained results, the aqueous extract of cinnamon bark shows a fungistatic effect on the growth and development of F. sporotrichioides, which opens the possibility of continuing research of cinnamon compounds as potential compounds of future control agents for the suppression of fungi of the genus Fusarium.