Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Foods ; 13(17)2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39272606

RESUMO

Storing ground beef at frozen temperatures prior to refrigerated display when using thermoforming vacuum packaging is not a common manufacturing practice. However, limited data on thermoforming packaging film and its interaction with meat quality suggests that more information is needed. The current study aimed to identify the influences of thermoforming packaging on the surface color and lipid oxidation of ground beef. Ground beef was portioned into 454 g bricks and packaged into one of three thermoforming films: T1 (150 µ polyethylene/EVOH/polyethylene coextrusion), T2 (175 µ polyethylene /EVOH/polyethylene coextrusion), and T3 (200 µ polyethylene/EVOH/polyethylene coextrusion), stored for 21 days at -20.83 °C (±1.50 °C), and displayed for 42 days at 3.0 °C ± 1.5 °C. There were no statistical differences for the packaging treatment of lipid oxidation (p = 0.0744), but oxidation increased throughout storage day (p < 0.0001). The main effects of treatment and day resulted in altered (p < 0.05) surface lightness (L*), redness (a*), yellowness, hue angle (°), red-to-brown (RTB), and relative myoglobin for met-myoglobin (MET), deoxymyoglobin (DMB), and oxymyoglobin (OMB). Surprisingly, there was an interaction between treatment and day for the calculated relative values of chroma (p = 0.0321), Delta E (p = 0.0155), and the ratio of a*:b* (p < 0.0001). These results indicate that thermoforming vacuum packaging can reduce the rate of deterioration that occurs to ground beef color and the rate of oxidation.

2.
Heliyon ; 10(18): e37650, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39323837

RESUMO

Moxa wool (MW), derived from the dried leaves of A r t e m i s i a a r g y i , plays a significant role in traditional Chinese medicine. However, the quality of MW varies with its storage period, impacting its therapeutic efficacy. Traditional methods for quality detection are limited and destructive. To address this, we propose a non-destructive detection method using hyperspectral imaging technology and machine learning algorithms to accurately identify the storage period of MW. Nevertheless, hyperspectral data poses challenges due to its high dimensionality and redundancy, leading to increased computational complexity. To overcome this, we employed principal component analysis (PCA), competitive adaptive reweighted sampling (CARS), and successive projection algorithm (SPA) for data dimensionality reduction and wavelength selection. The results demonstrate that these techniques significantly enhance the accuracy of MW storage year identification. For Nanyang MW, the CARS+SVM model achieved the highest accuracy rates of 99.8% in the visible-near-infrared (VNIR) range and 99.55% in the shortwave infrared (SWIR) range. Similarly, for Qichun MW, the SPA+SVM model achieved identification accuracies of 99.78% and 99.47% in the VNIR and SWIR ranges, respectively. This research provides valuable insights into the rapid detection of MW quality by indication of storage years and presents a novel approach for quality control of MW in the field of traditional Chinese medicine. The combination of hyperspectral imaging and machine learning offers a promising solution for efficient and accurate MW identification, contributing to the advancement of traditional medicine practices.

3.
BMC Plant Biol ; 24(1): 880, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342125

RESUMO

BACKGROUND: While water availability is important for quality at harvest, it also continues to influence the quality of pomegranates during storage. Reducing the amount of irrigation, in addition to water saving has different effects on bioactive compounds of pomegranate during storage time. This study was conducted to determine the influence of irrigation level on fruit quality changes during storage period of two commercial Iranian pomegranate cultivars ('Shishecap' and 'Malas-Yazdi'). Sustained deficit irrigation (SDI) was applied to plants that received 75% (moderate stress) or 50% (severe stress) of their normal water requirement. A control group received 100% of their water requirement. RESULTS: At harvest time and during storage period, fruit weight loss and some biochemical traits such as fruit total soluble solids (TSS), titratable acidity (TA), pH, total phenolic compounds (TPC), total anthocyanins content (TAC), antioxidant activity and vitamin C were measured in pomegranate fruits. Also, the quantity of the produced product was also measured at the time of harvesting. Results indicated that control fruits exhibited more weight loss than those produced under water deficit during the storage period in both years. According to results, fruit TSS, TAC, and antioxidant activity significantly increased during storage period but fruit TA and vitamin C significantly decreased throughout storage period. Also, reduction in irrigation level resulted in a decline in the yield. CONCLUSIONS: This study revealed a crucial link between irrigation level and the quality of pomegranate fruits, despite a reduction in the yield. This included affecting weight loss and the content of bioactive compounds, both at harvest and during storage.


Assuntos
Irrigação Agrícola , Armazenamento de Alimentos , Frutas , Valor Nutritivo , Punica granatum , Punica granatum/fisiologia , Frutas/crescimento & desenvolvimento , Frutas/química , Irrigação Agrícola/métodos , Armazenamento de Alimentos/métodos , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Irã (Geográfico) , Fenóis/metabolismo , Fenóis/análise , Antocianinas/análise , Antocianinas/metabolismo , Água
4.
Food Chem ; 460(Pt 2): 140544, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089023

RESUMO

A novel antibacterial film based on arabinoxylan (AX) was prepared by introducing ferulic acid (FA) to AX through a laccase-catalyzed procedure. The ferulic acid-arabinoxylan conjugates (FA-AX conjugates) have been characterized. Results showed that FA was successfully grafted onto the AX chains by covalent linkages, likely through nucleophilic addition between O-Ph in the phenolic hydroxyl group of FA, or through Michael addition via O-quinone intermediates. FA-AX conjugates showed improved crystallinity, thermal stability, and rheological properties, as well as a distinct surface morphology, compared with those of native AX. Moreover, FA-AX conjugates exhibited enhanced antibacterial ability against Staphylococcus aureus, Escherichia coli, Shewanella sp., and Pseudomonas sp. Mechanistic studies revealed that the enhanced antibacterial ability was due to the penetration of bacterial membrane by the phenolic molecule and the steric effect of FA-AX conjugates. The study demonstrates that the laccase-induced grafting method was effective in producing FA-AX conjugates; we have demonstrated its antibacterial ability and great potential in prolonging the shelf life of fresh seafood products.


Assuntos
Antibacterianos , Ácidos Cumáricos , Xilanos , Xilanos/química , Xilanos/farmacologia , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Lacase/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos
5.
Heliyon ; 10(14): e34573, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39113980

RESUMO

The Diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) tests can easily and rapidly measure the state of oxidative stress in the blood; they have been used to determine the relationship between oxidative stress and various diseases. However, the extent to which the blood storage period affects the analyzed data remains unclear. In clinical practice, the storage conditions for samples after blood collection vary. Therefore, the influence of blood storage conditions, particularly the reversible redox state, on biochemical tests has been thoroughly investigated. The storage conditions of the sample may affect its state; however, its effect on oxidative stress has not been investigated yet. In this study, considering that the time from blood collection to blood cell separation differs depending on the clinical setting, we analyzed the effect of storage period on the redox analysis data of blood samples stored for a certain period in a 4 °C refrigerator without centrifugation. Heparinized plasma samples from three healthy adult men in their 30s were subjected to the d-ROMs and BAP tests. The analysis was performed at the following 12 time points: immediately after blood collection; 1, 3, 6, 12, and 24 h later; and 2, 3, 4, 5, 6, and 7 days later. The d-ROMs and BAP values varied and were unstable after 1 h of blood collection. These findings suggest that centrifugation should be performed within 1 h after blood collection, at the latest. In a clinical setting, data should be interpreted with caution if centrifugation is performed more than 1 h after blood collection, even if heparin is added and the samples are stored at 4 °C.

6.
Food Chem X ; 23: 101538, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39071927

RESUMO

The quality of green tea deteriorates the longer it is stored. However, there is a lack of accurate and rapid methods for determining the storage period of tea. In this study, hyperspectral imaging (HSI) was used to determine the storage period of green teas stored at 4 °C (set 1) and 25 °C (set 2), and to quantify and visualize the main chemical components (e.g. catechins). In this study, three prediction algorithms were compared, in which partial least squares discriminant analysis outperformed the other models in qualitative discrimination, with 98% and 96% correct discrimination for two sets, respectively. Moreover, quantitative models for ester catechins, simple catechins, and total catechins were developed with Rp > 0.90 and RPD > 1.0, indicating that the models were reliable. Further, a more intuitive visualization of catechin content was achieved. In conclusion, the HSI provides a rapid, non-destructive method to determine the freshness of stored green tea.

7.
Foods ; 13(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998522

RESUMO

In recent years, the use of natural preservatives in food products has gained significant attention due to their potential health benefits and effectiveness. A standardized microbiological analysis was conducted on Slovak farm-produced lump goat cheese samples to determine the antibacterial activity of dry herbs and essential oils added to vacuum-packed goat cheese. We employed five dried herbs and five essential oils derived from the same plants. The microbiological quality of 145 fresh and vacuum-packed goat cheese samples was assessed. The number of coliform bacteria, total viable count, lactic acid bacteria, and microscopic filamentous fungi were examined in raw cheese samples stored for 12 days at 4 °C. All cheese samples were vacuum-packed (control samples were packed without vacuum). This study evaluated the potential benefits of using essential oils and dried herbs from thyme (Thymus serpyllum L.), black pepper (Piper nigrum L.), clove (Eugenia caryophyllus Thunb.), mint (Mentha × piperita L.), and basil (Ocimum basilicum L.) as preservatives. The essential oils were obtained from Hanus Ltd., Nitra, Slovakia, and were applied at a concentration of 2%. The dried herbs were obtained from Popradský caj (Poprad, Slovakia) and Mäspoma Ltd. (Zvolen, Slovakia). The results showed that all microorganism groups were significantly reduced in cheese samples following the application of essential oils throughout the entire storage period. During the preservation of cheese samples in polyethylene bags used for vacuum packing food, Lactococcus garvieae, L. lactis, Enterobacter cloacae, and Serratia liquefaciens were the most frequently isolated microbiota. Essential oils and dried herbs demonstrated antimicrobial potential during the storage of vacuum-packed goat cheese.

8.
Aesthetic Plast Surg ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913200

RESUMO

BACKGROUND: We previously showed comparable volume effects of injections of acellular adipose matrix (AAM), an adipose tissue-derived extracellular matrix, and conventional fat grafting in a murine model. Thus, AAM could be a novel allogenic injectable product. However, its retention rate poses a concern, as repeated AAM injections may be required in some cases. This study investigated the biological properties and therapeutic value of stored AAM and compared them with those of fresh AAM, in a murine model. METHODS: AAM was manufactured from fresh human abdominoplasty fat. Fresh and stored injectable AAM was prepared within 24 h and 3 months after generation, respectively. Either fresh or stored injectable AAM was injected into the scalp of athymic nude mice (0.2 mL/sample, n = 6 per group). After 8 weeks, graft retention was assessed through weight measurement, and histological analysis was performed, including immunofluorescence staining for CD31 and perilipin. RESULTS: Retention rate was significantly reduced in the stored compared to the fresh injectable AAM group. Nevertheless, histological analysis revealed comparable inflammatory cell presence, with minimal capsule formation, in both groups. Adipogenesis occurred in both groups, with no significant difference in the blood vessel area (%) between groups. CONCLUSIONS: Although the volume effects of stored AAM for soft tissue reconstruction were limited compared to those of fresh injectable AAM, stored AAM had similar capacity for adipogenesis and angiogenesis. This promising allogeneic injectable holds the potential to serve as an effective "off-the-shelf" alternative for repeated use within a 3-month storage period. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors https://link.springer.com/journal/00266 .

9.
Foods ; 13(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38790773

RESUMO

Postharvest rot is an urgent problem affecting the storage of winter jujube. Therefore, the development of new technologies for efficient and safe preservation is very important. This study aimed to elucidate the fungal microbiota found on the epidermis of jujube during the storage period using high-throughput sequencing, as well as to monitor the changes in quality indexes throughout this period. Through internal transcribed spacer (ITS) sequencing, we identified two phyla (Basidiomycota and Ascomycota) and six genera (Cryptococcus, Bulleromyces, Sporidiobolus, Alternaria, Pseudozyma, and Sporobolomyces), which potentially contribute to the spoilage and deterioration of jujube, referred to as "core fungal taxa". A high correlation was further found between preservation indices (including decay rate, firmness, and total soluble solids) and the growth of multiple core fungi over time. These findings will provide insights and a theoretical basis for further research on preservation techniques related to biological control during date fruit storage.

10.
J Sci Food Agric ; 104(11): 6756-6768, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38563620

RESUMO

BACKGROUND: Most microorganisms that cause food decay and the lower the shelf life of foods are fungi. Nanotechnologies can combat various diseases and deal with the application of nanomaterial to target cells or tissues. In this study selenium nanoparticles (Se-NPs) were synthesized using ascorbic acid and characterized by ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), X-ray diffraction and zeta potential. The different concentrations of As/Se-NPs were tested against various fungi, including Alternaria linicola, Alternaria padwickii, Botrytis cinerea, Bipolaris sp., Cephalosporium acremonium, Fusarium moniliform and Fusarium semitectum. This study tested the influence of coated As/Se-NPs on healthy strawberry fruits and those infected with Botrytis cinerea during 16 days of storage, with regard to shelf life, decay percentage, weight loss, total titratable acidity percentage, total soluble solids content (TSS) and anthocyanin content. RESULTS: Energy-dispersive X-ray analysis showed only two elements: selenium and oxygen. TEM images showed that the nanoparticles ranged in size between 26 to 39 nm and were rhombohedral in shape. Se-NPs showed antifungal activity against all tested fungi, the most effective being against Botrytis cinerea, Cephalosporium acremonium and Fusarium semitectum. During storage periods of strawberries fruits coated with As/Se-NPs, the shelf life was increased, and the number of decaying fruits was less than in control (uncoated) and coated infected fruits. The decline in weight loss was lower in coated fruits than in control fruits. CONCLUSION: These findings demonstrated that As/Se-NPs could effectively maintain the postharvest quality of strawberries, even when the fruit was infected with B. cinerea. © 2024 Society of Chemical Industry.


Assuntos
Botrytis , Conservação de Alimentos , Fragaria , Frutas , Fungos , Fusarium , Nanopartículas , Doenças das Plantas , Selênio , Fragaria/microbiologia , Fragaria/química , Frutas/química , Frutas/microbiologia , Conservação de Alimentos/métodos , Selênio/farmacologia , Selênio/química , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Nanopartículas/química , Fungos/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Antifúngicos/farmacologia , Antifúngicos/química , Alternaria/efeitos dos fármacos , Alternaria/crescimento & desenvolvimento , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Armazenamento de Alimentos
11.
Poult Sci ; 103(7): 103772, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38669822

RESUMO

This investigation aimed to assess how Japanese quail hatchability, growth, and carcass traits were affected by quail egg weight, storage length, and their interactions. One thousand two hundred sixty eggs of the commercial Japanese quail were purchased, and the average age of the birds was 13 wk. Quail egg weights were divided into 3 groups using a 3 × 4 factorial design: small (< 11 g), medium (11-12 g), and large (> 12 g). Each group had four storage times (1, 4, 7, and 10 d) and held 105 eggs. The study used a storage room with 70% humidity and 18°C. There were 12 treatment groups. For the final 3 d of incubation, the eggs were positioned in a hatching machine after being incubated for 14 d at 37.6°C and 65% humidity. For the study, 540 one-day-old Japanese unsexed quail chicks were randomly chosen and placed in groups of 5 that resembled the distribution of eggs. Three duplicates (15 chicks each) made up each of the 4 storage periods that comprised the 180 birds. The findings showed that the percentage of hatchable eggs is significantly influenced by their weight and the length of storage; medium and heavy-weight eggs exhibited higher percentages of hatchability while holding for 7 to 10 d. However, no significant interaction was observed-additionally, heavy egg weight results in higher weight at different ages. Egg weight also significantly impacts chick weight at hatch, 3 wk, and 6 wk. Egg weight and storage time affect dressing and carcass measurement percentages. We can conclude that the best results in terms of hatch and post-hatch efficiency, as well as carcass characteristics, were obtained with medium or heavy quail eggs and storage times of either 1 d or 4 d.


Assuntos
Coturnix , Óvulo , Animais , Coturnix/crescimento & desenvolvimento , Coturnix/fisiologia , Óvulo/fisiologia , Óvulo/crescimento & desenvolvimento , Fatores de Tempo , Feminino
12.
Food Chem X ; 22: 101327, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38590633

RESUMO

To investigate the effect of gelatin peptide on the inhibition of quality deterioration in stored pudding, gelatin peptide with antioxidant properties was added to pudding products. For this purpose, a pudding recipe containing gelatin peptides was created. The gelatin peptides were characterized based on their antioxidant activity and protein structure. It was found that gelatin peptides had better antioxidant properties, lower thermal stability and crystallinity, higher hydrophobic amino acid content, and greater surface hydrogen bond exposure than commercially available peptides. Properties such as the pH, colony growth, and sensory characteristics of the pudding were characterized at 4 °C and 25 °C. The results showed that the addition of 0.5-1.0 % gelatin peptide to pudding was capable of significantly (P< 0.05) slowing down the decline in pH and sensory scores of the pudding and significantly inhibiting colony growth. It could prolong its storage life by five days at 4 °C and three days at 25 °C.

13.
Foods ; 13(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611423

RESUMO

In this study, we present a comprehensive literature review of the potential impacts of climate change on potato storage. Potato preservation can help reduce food loss and waste while increasing long-term food security, as potatoes are one of the most important crops worldwide. The review's results suggest climate change can negatively affect potato storage, especially tuber sprouting and diseases in storage chambers. Lower Sielianinov coefficient values (indicating dry and hot conditions) during the vegetative season of potato growing can lead to earlier sprouting. For instance, a decrease of 0.05 in the Sielianinov coefficient during the growing season results in tubers stored at 3 °C sprouting 25 days earlier and tubers stored at 5 °C experiencing a 15-day reduction in dormancy. This is due to the fact that the dry and hot climate conditions during the vegetation period of potato planting tend to shorten potato tubers' natural dormancy, which further leads to earlier sprouting during storage. Furthermore, high Sielianinov coefficient values may lead to worse disease situations. The results also suggest that research about the impacts of climate change on potato storage is very limited at the current stage, and further studies are needed to address the key knowledge gaps identified in this study.

14.
Food Sci Nutr ; 12(4): 2619-2633, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628216

RESUMO

The present study aimed to prepare and evaluate a new probiotic functional beverage, using single-probiotic and compound probiotic fermentation on okara. Four different forms of fermentation microorganisms used were Lacticaseibacillus rhamnosus S24 (Lr), Lacticaseibacillus paracasei 6244 (Lp), Lactobacillus acidophilus 11,073 (La), and mixed fermentation (Lr + Lp + La). The physicochemical properties, antioxidant activity, flavor change, and storage period of fermented okara beverages with probiotics were investigated. The results showed that different fermentation schemes could significantly improve the physicochemical properties, antioxidant activity, and sensory quality of the okara beverages. The number of viable bacteria in the Lp group (3.53 × 108 CFU/mL), isoflavone content (0.514 µg/mL) were the highest; total phenol and flavonoid content were 3.32 and 5.68 times higher than in the CK group, respectively. DPPH and ABTS+ free radical scavenging rates were increased by 11.32% and 20%, respectively (p < .05). Through SPME/GC-MS analysis, 44 volatile compounds were identified in the Lr + Lp + La groups, mainly as a result of changes in alcohols and aldehydes produced by fermentation metabolism. It enhances the floral and fruity aroma of the okara beverage. All probiotic-fermented okara beverages can be stored at 4°C for 15 days, with probiotic activity greater than 107 CFU/mL. This study can obtain a probiotic okara beverage rich in soybean isoflavones and with good flavor. Overall, okara can be used to develop functional beverages containing probiotics and contribute to a zero-waste approach in the food industry.

15.
Molecules ; 29(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675551

RESUMO

This study aimed to determine the effect of the drying method (freeze-drying, air-drying), storage period (12 months), and storage conditions (2-4 °C, 18-22 °C) applied to two legume species: green beans and green peas. The raw and dried materials were determined for selected physical parameters typical of dried vegetables, contents of bioactive components (vitamin C and E, total chlorophyll, total carotenoids, ß-carotene, and total polyphenols), antioxidative activity against the DPPH radical, and sensory attributes (overall quality and profiles of color, texture, and palatability). Green beans had a significantly higher content of bioactive components compared to peas. Freeze-drying and cold storage conditions facilitated better retention of these compounds, i.e., by 9-39% and 3-11%, respectively. After 12 months of storage, higher retention of bioactive components, except for total chlorophyll, was determined in peas regardless of the drying method, i.e., by 38-75% in the freeze-dried product and 30-77% in the air-dried product, compared to the raw material.


Assuntos
Antioxidantes , Clorofila , Fabaceae , Liofilização , Verduras , Antioxidantes/análise , Antioxidantes/química , Verduras/química , Clorofila/análise , Clorofila/química , Fabaceae/química , Carotenoides/análise , Carotenoides/química , Armazenamento de Alimentos/métodos , Polifenóis/análise , Polifenóis/química , Ácido Ascórbico/análise , Ácido Ascórbico/química , Dessecação/métodos , beta Caroteno/análise , beta Caroteno/química , Pisum sativum/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Vitamina E/análise , Vitamina E/química
16.
Food Microbiol ; 121: 104497, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637068

RESUMO

Daqu is a saccharification agent required for fermenting Baijiu, a popular Chinese liquor. Our objective was to investigate the relationships between physicochemical indices, microbial community diversity, and metabolite profiles of strong-flavor Jinhui Daqu during different storage periods. During different storage periods of Jinhui Daqu, we combined Illumina MiSeq sequencing and non-target sequencing techniques to analyze dynamic changes of the microbial community and metabolite composition, established a symbiotic network and explored the correlation between dominant microorganisms and differential metabolites in Daqu. Fungal community diversity in 8d_Daqu was higher than that in 45d_Daqu and 90d_Daqu, whereas bacterial community diversity was higher in 90d_Daqu. Twelve bacterial and four fungal genera were dominant during storage of Daqu. Bacillus, Leuconostoc, Kroppenstedtia, Lactococcus, Thermomyces and Wickerhamomyces decreased as the storage period increased. Differences of microbiota structure led to various metabolic pathways, and 993 differential metabolites were found in all Daqu samples. Differential microorganisms were significantly related to key metabolites. Major metabolic pathways involved in the formation of amino acids and lipids, such as l-arogenate and hydroxyproline, were identified. Interactions between moisture, acidity, and microbes may drive the succession of the microbial community, which further affects the formation of metabolites.


Assuntos
Bacillus , Microbiota , Fermentação , Bactérias , Metaboloma
17.
J Food Sci ; 89(3): 1442-1453, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38258911

RESUMO

C-phycocyanin (C-PC) is a natural high-value blue phycobiliprotein from Spirulina platensis, which has wide biological applications in food, pharmaceutical, and cosmetics. However, the freshness of S. platensis powder (SPP) materials and C-PC purification play critical roles in evaluating the stability and bioactivities of C-PC, which severely affect its commercial application. This study investigated the effect of spray-dried SPP freshness on the biofunctional activities of analytical grade C-PC (AGC-PC). The yield of AGC-PC extracted from spray-dried SPP could reach 101.88 mg/g (75% recovery ratio) after purification by reversed phase high-performance liquid chromatography (RP-HPLC) system. The half-life period (t1/2 ) of AGC-PC stability at 60°C and 8000 lux light could remain 171.70 min and 176.11 h within 6 months storage of spray-dried SPP. The emulsifying activity index (EAI) and foaming capacity (FC) of AGC-PC from fresh-dried SPP showed maximum values of 68.64 m2 /g and 252.9%, respectively. The EC50 of AGC-PC from fresh spray-dried SPP on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline -6-sulfonic acid (ABTS+·) scavenging activity could reach 63.76 and 92.93 mg/L, respectively. The EC50 of AGC-PC from fresh spray-dried SPP on proteinase inhibition and anti-lipoxygenase activity were 302.96 and 178.8 mg/L, respectively. The stability and biofunctional activities of AGC-PC remained stable within 6 months storage of SPP, and then rapidly decreased after 9 months storage due to the disintegration of the trimeric (αß)3 and hexameric (αß)6 forms of C-PC. It is concluded that the optimal storage period of SPP for preparation of AGC-PC in commercial use should be less than 6 months. PRACTICAL APPLICATION: The C-phycocyanin (C-PC) from dried Spirulina platensis powder (SPP) has been widely applied in food nutritional, florescent markers, pharmaceuticals, cosmetics, etc, due to its blue color, fluorescence, and antioxidant properties. However, the effect of dried SPP freshness on the stability and functional activity of C-PC has been rarely reported. This study found that the thermostability, photostability, emulsifying, antioxidant, and anti-inflammatory activities of analytical grade C-PC (AGC-PC) significantly decreased after 6 months storage of SPP. Based on investigations, we have proposed that the suitable storage time of dried SPP for preparation of AGC-PC in commercial application should be within 6 months.


Assuntos
Ficocianina , Spirulina , Antioxidantes/farmacologia , Pós , Spirulina/química
18.
Food Chem ; 440: 138186, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38104456

RESUMO

Navel orange remains metabolized continuously during postharvest storage, but few studies have monitored the changes of these metabolites. Therefore, HS-SPME-GC-MS and UPLC-Q-TOF/MS were used to comprehensively investigate the dynamic changes of the components of Gannan navel orange during storage at room temperature. A total of 62 volatile components and 68 non-volatile components were identified. Principal Component Analysis and Partial Least Squares Discriminant Analysis showed that navel orange under different storage periods were clearly distinguished. Combined with VIP > 1 and p < 0.05, 19 volatile and 27 non-volatile differential metabolites were obtained. KEGG enrichment analysis revealed that flavonoid biosynthesis (map00941) was the primary metabolic pathway. The middle storage period had a higher antioxidant enzyme activity, but the malondialdehyde content was the opposite. These results reveal the changes of postharvest components of Gannan navel orange, providing a theoretical basis for the storage and product development of navel orange.


Assuntos
Citrus sinensis , Microextração em Fase Sólida , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Sólida/métodos , Temperatura , Metabolômica/métodos , Antioxidantes
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-988731

RESUMO

ObjectiveThe aim of this study is to investigate change of platelet count in red blood cell (RBC) units at different storage periods and explore the efficiency of platelet removal by leukocyte filter. MethodsA total of 58 RBC units were divided into four groups according to different storage periods: 1 week Group (16), 2 weeks Group (16), 3 weeks Group (14) and 4 weeks Group (12). RBC units in the four groups were filtered through leukocyte filter. The RBC samples before and after filtration were obtained. The platelet count was detected by automatic blood cell counter and the efficiency of platelet removal was calculated. RBC samples before filtration were made into blood cell smears. The blood cell smears were dyed with Wright-Giemsa stain, and the morphology of platelets was observed through a microscope. ResultsThe platelet count in RBC units stored for 1, 2, 3 and 4 weeks was (286.5±62.34)×109/L, (238.0±57.37)×109/L, (193.6±56.21)×109/L and (167.8±24.76)×109/L, respectively. Platelet count in blood stored for 3 weeks (P<0.01) and 4 weeks (P <0.000 1) were significantly lower than those stored for 1 weeks. When observed in the blood smears of RBC units at different storage periods, platelets with normal morphology were distributed in clump and scattered style. The platelet removal rates of the four groups were (80.13±9.06) %, (76.41±10.13) %, (77.78±9.30) % and (70.63±9.39) %, respectively, with no significant difference (P >0.05). ConclusionsPlatelet count in RBC units decreases gradually as the storage period increases, but most platelets still remain in RBC units of late storage periods (3 weeks and 4 weeks). The leukocyte filter is able to remove most of the platelets, and the removal efficiency is similar among the groups.

20.
Front Plant Sci ; 13: 1034535, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523617

RESUMO

Because of their unique features, nanomaterials have been proposed and have gained acceptance in postharvest applications in fruit. Increasing the storage life and improving the quality of Valencia oranges was investigated using nano-chitosan. A chitosan nanoparticle was prepared by using high-energy ball milling. Chitosan nanoparticles were characterized by Dynamic light scattering, FTIR spectroscopy and Surface morphology by transmission electron microscopy. Fully mature Valencia oranges were harvested and then coated with one of these concentrations (0.2, 0.4, and 0.8% nano-chitosan) and control. The fruits were stored under room storage conditions for 75 days. The quality parameters (fruit weight losses, fruit decay percentage, fruit firmness, total acidity, total soluble solids percentage and T.S.S./acid ratio, ascorbic acid content) were taken in biweekly intervals after 0, 15, 30, 45, 60, and 75 days. Beside the in vitro testing of antifungal activity of chitosan nanoparticles. According to the findings of the two succeeding seasons, the nano-chitosan 0.8% treatment showed the best effects and had the lowest rate of fruit weight loss, fruit deterioration, and T.S.S./acid ratio in comparison to the other treatments in both seasons. Furthermore, the 0.8% nano-chitosan reveled the highest levels of fruit hardness and fruit pulp firmness. Fruit weight loss, fruit deterioration, TSS, and TSS/acid ratio, as well as other metrics, were steadily elevated prior to the storage time. The best results were obtained when Valencia oranges fruits were treated with 0.8% nano-chitosan for 75 days at room temperature.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA