Applied Food Research最新文献

One of the most important foods in the world is milk, due to its nutrients and composition. Milk also contains lactic acid bacteria (LABs), which can produce antimicrobial compounds and organic acids; an essential factor in developing different methods to control other bacteria. Another critical factor is that several species of LABs are considered potential probiotics, offering several health benefits. This study aimed to isolate, identify LABs, characterize the antimicrobial susceptibility profile, and evaluate the inhibition potential against Staphylococcus aureus (ATCC 25923), Listeria monocytogenes (ATCC 7644), Escherichia coli (ATCC 25922) and Salmonella Typhimurium (ATCC 14028); as well as verifying the acidification capacity, survival of simulated in vitro gastrointestinal conditions and identification of virulence genes and bacteriocin-producing genes. The study was carried out with LABs previously isolated from milk of cows with clinical mastitis, low and high (Somatic Cells Count) in herds from all regions of Brazil (South, Southeast, Central-West, North, and Northeast). One hundred and ten strains were selected for identification using the MALDI-TOF technique. The genera with the most significant spectrum of action were Lactococcus, Lactobacillus, and Pediococcus in the antimicrobial action test against pathogens, concluding that Lactobacillus showed resistance to several antibiotics. The analysis of antimicrobial action made it possible to verify the potential production of antimicrobial compounds by LABs against the primary pathogens of food origin. The most significant reduction in pH could be observed from 24 h to 48 h, ranging from 6.8 (0 h) to 4.74 (48 h) for Lactobacillus and Lactococcus. All isolates survived tolerance tests at pH=3.0 and bile salts (0.5 %), with survival rates ranging from 34.2 to 69.9 % at pH = 3.0 and above 82 % at 0.5 % bile salts. Lacotococcus and Lactobacillus isolates presented the plnEF and plnNC8 genes. This study contributes to the search for alternatives in the treatment of bacterial infections with a reduction in the use of antibiotics, which, due to the increase in bacterial resistance, is causing difficulties in treating diseases caused by these microorganisms. pH is an important parameter when it comes to food safety and conservation. Tolerance to acid stress and bile salts are important properties in evaluating probiotic potential and the ability to maintain high counts under these conditions. The presence of the plnEF and plnNC8 genes suggests bacteriocin production.

This study assessed the effect of pH (5.7, 6.8, and 8.0, adjusted using phosphate buffer) and calcium chloride (0.2 g kg^-1, 0.6 g kg^-1, and 1.0 g kg^-1) on the chlorophyllase (Chlase) activity and thermal inactivation in mulberry leaves at temperatures ranging from 75 ℃ to 100 ℃. The overall lethality was calculated, and the subsequent data were described using a two-fraction kinetics model. The results showed that the Chlase activity displayed an initial increase at a higher pH level and calcium chloride concentration, followed by a decline. Furthermore, the pH and calcium chloride also affected the Chlase inactivation kinetics. Weak acidity (pH 5.7) distinctly promoted Chlase inactivation during thermal treatment, while weakly alkaline conditions (pH 8.0) enhanced heat stability. The presence of calcium chloride increased the Chlase thermal stability, while the response to thermal processing (TP) varied depending on the calcium chloride concentration.

Chitosan is a biopolymer abundantly present in the exoskeletons of crustaceans like shrimp and crabs. Chitosan is derived from chitin by a process called deacetylation, which includes demineralization, deproteinization, and deacetylation steps. Its many attributes, including biodegradability, biocompatibility, and antibacterial action, have made it extensively useful in food processing sector. Chitosan, due to its different reactive groups (primary -OH, secondary -OH, and -NH2), has been discovered to impede the growth of wide range of fungi and both gram-positive and gram-negative bacteria. This is achieved through electrostatic interactions with the cell wall, cell membrane, and cytoplasmic components of the microorganisms. Papaya is a significant tropical fruit belonging to the genus Carica. Post-harvest losses in papaya are high, owing to factors such as physical damage, microbial proliferation, and moisture depletion. Utilizing chitosan coating, either alone or in combination with other preservative components, has been discovered to effectively mitigate these variables, resulting in decreased post-harvest losses and enhanced papaya shelflife. The review analyzes the impact of chitosan coating on the antibacterial characteristics, quality preservation, and decrease of post-harvest losses in papaya. Applying a chitosan coating on papaya has great potential in enhancing the sustainability of papaya production and supply.

Plant-based foods have prevailed around the world, and various high-quality plant proteins have been explored and studied in recent years. Chia seeds have received extensive attention for their rich nutrients, with up to 20 % protein content. Protein in chia seed contains 18 essential and non-essential amino acids, which can be considered as an alternative plant protein source for individuals who are vegans and allergic to soy or gluten. This review provides an overview of the functional properties of chia seed protein and its fractions, focusing on solubility, water and oil absorption capacity, water and oil holding capacity, emulsifying, foaming as well as gelling properties. The chemical methods of chia seed protein processing using acidic or alkaline solutions, including purification and fractionation, are also discussed. The few literature studies on the application of chia protein, chia seeds or chia seed flour used in food production were exclusively investigated. Furthermore, the current challenges and future opportunities related to the economy, environment, and ethics render it the potential to become a main ingredient for plant-based foods are also thoroughly analysed.

Synbiotic yogurts can offer several potential benefits due to the combination of yogurts probiotics, prebiotics, and the nutritional qualities of milk. Local yogurt variants might add to the variety of probiotic alternatives because they frequently have distinct microbial communities. Employing indigenous strains not only represents cultural preferences but also increases the probability of obtaining bacteria adapted to the surrounding environment. This study was intended to isolate and characterize potential lactic acid bacterial strains from local yogurt and assess the effectiveness of inulin on the physicochemical and microbiological properties during the fermentation of synbiotic yogurt. A total of eight strains were identified and isolated. Two chosen isolates were combined with inulin at 0, 0.5, 1, and 1.5 % concentrations to produce synbiotic yogurts. The physicochemical and microbiological properties were assessed during the fermentation process of synbiotic yogurts. The result showed that the isolated Lactobacillus spp. and Streptococcus spp. strains had probiotic characteristics and good growth. After the fermentation, the yogurt sample containing 1.5 % inulin had the highest count of Lactobacillus spp. (8.17 ± 0.01 log CFU/ml) and Streptococcus spp. (8.03 ± 0.03 log CFU/ml), highest optical density (2.931 ± 0.001), acidity (1.43 ± 0.03), and water-holding capacity (63.54 ± 0.51), and lowest syneresis (34.75 ± 0.48). The addition of inulin did not affect color during the fermentation of synbiotic yogurt. This study concluded that inulin could boost yogurt's stability when combined with local lactic acid bacteria strains.

Aflatoxin contamination in agricultural products such as pistachios threatens human health. Ozone has intense antimicrobial activity against microorganisms. The effect of ozone-treated time (3,4 and 5 h) and stirring time (10, 15 and 20 min) on microbial, aflatoxin content, peroxide value, and sensory properties of aflatoxin contaminated pistachios were investigated in this study. The microbial test results also show a significant reduction of microbial load in ozone-treated samples. According to the results, ozone gas caused a significant reduction in aflatoxin levels in pistachio kernels. Aflatoxins B1, B2, G1, G2 and total which was 33.5, 1.5, 0.06, 0. 31 and 35.13 ppb in the control sample, reached 0 ppb after 5 h of ozone-treatment (15 or 20 min). The results show that the longer the ozone gas is gasified, the higher the peroxide value. The lowest and highest peroxide value was observed in the control and the ozone-treated sample for 5 h (stirring the samples every 20 min), respectively. All peroxide values were below the allowable limit (1 meq/kg). The results of sensory evaluation show that ozonation did not have a negative effect on the falvor, texture, and color score of pistachios, but only had a significant effect on the aroma of pistachios that were ozone-treated for 5 h. According to results, 3 h of ozonation and stirring of pistachios every 20 min is recommended as the best treatment for reducing microbial load, aflatoxin content, peroxide value and maintaining the sensory properties of dried pistachios.

The agri-food system plays a critical role in meeting global food demand, with traceability and food safety becoming key priorities for producers and consumers. Consumer trust, influenced by perceptions of food safety, quality and origin, has been declining due to the complexity of the food supply chain. Blockchain technology (BCT) has emerged as a promising solution to increase transparency, ensure data immutability, and improve food safety and quality. This study employs a systematic literature review methodology to analyze consumer perceptions of BCT in the agri-food sector. Using the PRISMA method, articles from Scopus®, Web of Science®, and PubMed® were reviewed, focusing on publications from 2019 to 2023. A total of 34 relevant studies were identified and examined to determine the key factors influencing consumer acceptance of BCT-tracked foods. Results indicate that trust, ngness to pay, perception of traceability, perceived risk and perceived safety are critical variables influencing consumer perceptions of BCT. Trust in BCT is supported by its ability to ensure data integrity and transparency, which significantly influences consumer behavior and adoption intentions. Consumers' willingness to pay for BCT-tracked products is influenced by their awareness and understanding of the benefits of BCT in improving food safety. In addition, BCT's potential to reduce perceived risk and improve supply chain transparency further enhances consumer trust. In conclusion, promoting consumer confidence through transparent information provided by BCT is essential for its widespread adoption in the agri-food sector. In order to educate consumers about the benefits of BCT and promote greater acceptance, the study recommends targeted communication strategies. Future research should focus on real-world applications and consumer education to further validate the impact of BCT on improving food safety and trust.

The aim of this study was to recover bioactive compounds from Smallanthus sonchifolius roots, including flavonoids, terpenoids, phenolics, vitamin C, and reducing sugar contents, as well as to examine antioxidant activities using ultrasonic-assisted and microwave-assisted extraction technique. Single-factor experiments were employed to explore the impact of various independent variables, including concentration, extraction method, power, duration, temperature, and pH, on the dependent variables of yacon extraction using the ultrasonic-microwave-assisted extraction method. The Plackett-Burman Design Model was used to screen the parameters that significantly influenced the extraction efficiency. Box-Behnken Design Model was utilized to optimize the ultrasonic-microwave-assisted extracting process to acquire bioactive compounds. The highest yield of total flavonoid contents was obtained with 4.00 of pH, 743.33 W of microwave power, and 39.08°C of ultrasonic temperature. According to reducing sugar contents yield optimization, the optimum conditions were 3.98 of pH, 36.17 seconds of microwave time and 40°C of ultrasonic temperature. To optimize vitamin C concentration, the optimized conditions were 1:40 g/mL of sample-to-solvent ratio, 3.99 of pH, 45.33 seconds of microwave time, and 451.09 W of ultrasonic power. Regarding total terpenoids yield, optimized conditions for extracting were 1:40 g/mL of sample-to-solvent ratio, 2.48 of pH, 30.49 seconds of microwave time, and 49.48 °C of ultrasonic temperature. Under optimized conditions, the recovery yield of flavonoid, terpenoid, vitamin C, and reducing sugar contents were 7.95 mg rutin equivalents/g, 47.93 mg ursolic acid equivalents/g, 107.78 mg ascorbic acid/g, and 230.39 mg D-glucose equivalents/g, respectively. Ultrasonic-microwave-assisted extraction showed significantly higher performance than singular extracting methods and is regarded as a sustainable and effective approach to recover target compounds from yacon roots.

The pre-fermentative steps play an important role on the characteristics of white wine. Among them, the grape pressing is a crucial phase as the extraction of grape compounds occurs having a relevant impact on the composition of must and, consequently, of wine. The grape pressing is particularly important for the sparkling wine production as it influences the acidity and phenol concentration of must.

The aim of this review was to explore the must changes occurring during grape pressing. The pressing technologies and conditions were discussed and compared, considering their impact on must composition. Special attention was devoted to the pressing of grape for obtaining must addressed to sparkling wine production, considering the challenges for preserving the acidity and managing the extraction of phenolic and aromatic compounds. Hence, the current awareness and the gaps of knowledge are presented and discussed.

Pressing grapes for white and sparkling winemaking requires a controlled approach to maintain must integrity and ensure the quality of the final product. High constraints on solid parts mean higher extraction of phenolics, aroma precursors and potassium. The latter, causing the precipitation of tartaric acid, leads to a pH increase and acidity decrease. Higher extraction of phenolics can make the must and the wine more susceptible to oxidation. Different conditions adopted in terms of grape temperature, oxygen exposure, applied pressure, fractioning and types of press affect the composition of must. Future researches on this step should also consider the grape composition.

Color change is a crucial parameter in the drying process of products like carrot slices. However, the impact of microwave output power on the kinetics of color change, physicochemical properties, and bioactive compounds of pretreated carrot (Daucus carota L) slices during drying has not been fully explored. Therefore, this study aims to determine the color change kinetics, physicochemical properties, and bioactive compounds of pretreated carrot slices during microwave drying. Blanched carrot slices (3–4 min) were dipped in potassium metabisulfite (0.25% w/w, 20 min) and then dried using a microwave dryer at different power levels (170 W, 340 W, and 510 W). The color change kinetics were assessed using Hunter L* (whiteness/darkness), a* (redness/greenness), and b* (yellowness/blueness) coordinates. Additionally, moisture content, pH, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity, and β-carotene levels were analyzed according to established methods. The mathematical modeling of color change revealed that L*, a*, and b* values fit both zero-order and first-order kinetic models, while the total color change (ΔE) followed a zero-order kinetic model. Among the three microwave power levels, 170 W showed superior physicochemical characteristics: moisture content (5.1 %), pH (5.45±0.12), total phenolic content (153.23±1.61 g/ml), total flavonoid content (23.33±0.76 g/ml), antioxidant activity (63.90±0.78 g/ml), and β-carotene content (67.28±0.61 ppm). Therefore, it is recommended to use a pre-treated 170 W microwave output power for drying carrots and other fruits and vegetables to preserve color, nutrients, and energy.