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1.
Int J Biol Macromol ; : 132618, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38795880

ABSTRACT

High-temperature blanching (HTB) is the primary process that causes texture softening in frozen yellow peaches. The implementation of low-temperature blanching reduced pectin methyl esterification, increased pectin cross-linking, and mitigated pectin depolymerization during the subsequent HTB, leading to the superior texture of frozen yellow peaches with enhanced water holding capacity, higher fracture stress, and initial modulus. However, adding 2 % calcium lactate (w/v) during low-temperature blanching did not further improve the texture of frozen yellow peaches. Instead, it softened the texture by reducing Na2CO3-soluble pectin (NSP) and increasing water-soluble pectin (WSP) content. This study provided a theoretical basis for applying low-temperature blanching to improve the texture of frozen yellow peaches.

2.
Heliyon ; 10(7): e28278, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38560217

ABSTRACT

Background: Globally, lung carcinoma remains the leading cause of death, with its associated morbidity and mortality rates remaining elevated. Despite the slow advancement of treatment, the outlook remains bleak. Cellular senescence represents a halt in the cell cycle, encompassing a range of physiological and pathological activities, along with diverse phenotypic alterations, including variations in secretory phenotype, macromolecular harm, and metabolic disturbances. Research has revealed its vital function in the formation and growth of tumors. This study aimed to examine cellular senescence-related mRNAs linked to the outlook of non-small cell lung cancer (NSCLC) and to formulate a predictive risk framework for NSCLC. Methods: We acquired the NSCLC expression data from The Cancer Genome Atlas (TCGA) to examine mRNAs linked to cellular senescence. Both single-variable and multiple-variable cox proportion risk assessments were utilized to determine the traits of cellular senescence-related mRNAs linked to NSCLC prognosis. Subsequently, the prognostic model for cellular senescence-related mRNAs was integrated with clinical-pathological characteristics to create a prognostic nomogram. Furthermore, the study delved into the risk-oriented predictive model, examining immune infiltration and responses to immunotherapy among both high and low-risk categories. Results: Utilizing both univariate and multivariate Cox proportion risk assessments, a risk model comprising 12 mRNAs associated with cellular aging was ultimately developed: IGFBP1, TLR3, WT1, ID1, PTTG1, ERRFI1, HEPACAM, MAP2K3, RAD21, NANOG, PRKCD, SOX5. Univariate analysis and multivariate analysis illustrated that the risk score served as a standalone indicator for prognosis, and the hazard ratio (HR) of the risk score were 1.182 (1.139-1.226) (p < 0.001) and 1.162 (1.119 - 1.206) (p < 0.001), respectively. Individual prognoses were forecasted using nomogram, c-index, and principal component analysis (PCA). Furthermore, the risk-oriented model revealed notable statistical variances in immune infiltration and response to immunotherapy among the high and low risk categories. Conclusions: This study shows that mRNAs related to cell senescence associated with prognosis are reliable predictors of NSCLC immunotherapy reaction and prognosis.

3.
Food Chem X ; 22: 101337, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38601949

ABSTRACT

Hot air drying (HD), vacuum freeze drying (FD), and pilot-scale freeze drying (PSFD) are extensively used to prepare peach slices. However, the aroma of hot air drying and vacuum freeze-drying is yet to be addressed. In this study, HS-SPME-GC-MS was used to characterize and quantify the volatile compounds in peach slices. First, 33, 36, and 46 volatile compounds were identified and quantified in the HD, FD, and PSFD groups, respectively. PSFD is preferable to HD and FD in terms of the volatile compound types, content, and aroma profiles. PSFD was selected for subsequent permeation and dehydration experiments. The key aroma compounds with an OAV ≥ 1 were found in the PSFD30 group. GC-O analysis was conducted on the PSFD30 group, leading to the preliminary identification of 2-methylbutanal, pentanal, hexanal, 2-hexenal, phenylacetaldehyde, ethyl acetate, 2-methylbutyl acetate, ethyl lactate, linalool, methyl heptenone, and γ-octalactone as distinctive aromas in dried peach slices.

4.
J Texture Stud ; 55(2): e12830, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38581175

ABSTRACT

Freezing and blanching are essential processing steps in the production of frozen yellow peaches, inevitably leading to texture softening of the fruit. In this study, the synergistic mechanism of stem blanching, freezing conditions (-20°C, -40°C, -80°C, and liquid nitrogen [-173°C]), and sample sizes (cubes, slices, and half peaches) on macroscopic properties of texture, cellular structure, and ice crystal size distribution of frozen yellow peaches were measured. Blanching enhanced the heat and mass transfer rates in the subsequent freezing process. For nonblanched samples, cell membrane integrity was lost at any freezing rate, causing a significant reduction in textural quality. Slow freezing further exacerbated the texture softening, while the ultra-rapid freezing caused structural rupture. For blanched samples, the half peaches softened the most. The water holding capacity and fracture stress were not significantly affected by changes in freezing rate, although the ice crystal size distribution was more susceptible to the freezing rate. Peach cubes that had undergone blanching and rapid freezing (-80°C) experienced 4% less drip loss than nonblanched samples. However, blanching softened yellow peaches more than any freezing conditions. The implementation of uniform and shorter duration blanching, along with rapid freezing, has been proven to be more effective in preserving the texture of frozen yellow peaches. Optimization of the blanching process may be more important than increasing the freezing rate to improve the textural quality of frozen yellow peaches.


Subject(s)
Prunus persica , Steam , Freezing , Food Preservation , Ice
5.
J Sci Food Agric ; 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597282

ABSTRACT

BACKGROUND: Peach gum (PG) is an exudate of the peach tree (Prunus persica of the Rosaceae family), which consists primarily of polysaccharides with a large molecular weight and branching structure. Consequently, PG can only swell in water and does not dissolve easily, which severely limits its application. Current conventional extraction methods for PG polysaccharide (PGPS) are time consuming and inefficient. This study investigated the impact of ultrasonic-assisted extraction (UAE) on PGPS structure and conformation, and their relationship to hypoglycemic activity in vitro. RESULTS: In comparison with conventional aqueous extraction, UAE enhanced PGPS yielded from 28.07-32.83% to 80.37-84.90% (w/w) in 2 h. It drastically decreased the molecular size and conformational parameters of PGPS, including weight-average molecular weight (Mw), number-average molecular weight (Mn), z-average radius of gyration (Rg), hydrodynamic radius (Rh) and instrinsic viscosity ([η]) values. Peach gum polysaccharide conformation converted extended molecules to flexible random coil chains or compact spheres with no obvious primary structure alteration. Furthermore, UAE altered the flow behavior of PGPS solution from that of a non-Newtonian fluid to that of a Newtonian fluid. As a result, PGPS treated with UAE displayed weaker inhibitory activity than untreated PGPS, mostly because UAE weakens the binding strength of PGPS to α-glucosidase. However, this negative effect of UAE on PGPS activity was compensated by the increased solubility of polysaccharide. This enabled PGPS to achieve a wider range of doses. CONCLUSION: Ultrasonic-assisted extraction is capable of degrading PGPS efficiently while preserving its primary structure, resulting in a Newtonian fluid solution. The degraded PGPS conformations displayed a consistent correlation with their inhibitory effect on α-glucosidase activity. © 2024 Society of Chemical Industry.

6.
Food Chem ; 450: 139375, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-38653052

ABSTRACT

Cooked off-flavor was produced during the processing of concentrated peach puree (CPP), which led to aroma deterioration. Enzymatic treatment was beneficial in eliminating off-flavors and improving the aroma quality. Herein, the efficacy of glycosidase (AR2000), glucose oxidation (GOD), and their combination on the inhibition of off-flavors and aroma enhancement were evaluated. Compared with CPP, contents of benzaldehyde, benzyl alcohol, nonanal, and linalool increased by 198%, 1222%, 781%, and 71% after AR2000 treatment via the metabolisms of shikimate, glucose, linoleic acid, and linolenic acid, leading to the strengthening of floral and grassy. Due to the removal of 1-octen-3-one via linolenic acid metabolism, cooked off-flavor could be significantly weakened by GOD. Furthermore, Furthermore, the combination of AR2000 and GOD could not only inhibit the production of 1-octen-3-one to weaken the cooked note but also enhance grassy and floral attributes via the increase of aldehydes and alcohols.


Subject(s)
Flavoring Agents , Glucose Oxidase , Metabolomics , Odorants , Prunus persica , Volatile Organic Compounds , Glucose Oxidase/metabolism , Glucose Oxidase/chemistry , Volatile Organic Compounds/metabolism , Volatile Organic Compounds/chemistry , Odorants/analysis , Flavoring Agents/chemistry , Flavoring Agents/metabolism , Prunus persica/chemistry , Prunus persica/metabolism , Prunus persica/enzymology , Glucosidases/metabolism , Taste , Fruit/chemistry , Fruit/metabolism , Fruit/enzymology
7.
Food Chem ; 450: 139394, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-38653058

ABSTRACT

In this study, the effect of osmotic dehydration (OD) pretreatment with various sugar (erythritol, glucose, and trehalose) on the quality of hot-air-predried peach slices was investigated, particularly focusing on electrical properties, texture, thermal stability, and cell wall strength. Furthermore, the correlation between the properties of predried peach slices and the texture of the instant controlled pressure drop (DIC) dried peach chips was explored. OD pretreatments improved the stability and integrity of the cell wall and cell membrane of pre-dried peach slices, which inhibited the excessive expansion of samples during DIC drying. Especially, peach chips with trehalose-OD exhibited the highest crispiness (1.05 mm), the highest hardness (101.34 N) was obtained in erythritol-OD samples. Overall, the type of osmotic agents affected the texture of DIC peach chips with OD pretreatments. It should be noted that trehalose is a promising osmotic agent for controlling and regulating the quality of DIC peach chips.


Subject(s)
Osmosis , Prunus persica , Prunus persica/chemistry , Food Handling/instrumentation , Desiccation/methods , Hot Temperature , Pressure , Food Preservation/methods , Food Preservation/instrumentation
8.
Food Chem ; 451: 139397, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38678662

ABSTRACT

This study investigated the dynamic degradation process of peach gum polysaccharide (PGPS) within ultrasonic field. The results show that the molecular weight, intrinsic viscosity, and polydispersity of PGPS were rapidly reduced within the initial 30 min and then gradually decreased. The solubility of PGPS was drastically improved from 3.0% to 40.0-42.0% (w/w) after 120 min. The conformation of PGPS changed from an extended chain to a flexible random coil within initial time of ultrasound, and gradually tended to be compact spheres. The apparent viscosity of PGPS significantly decreased after 30 min, and PGPS solution exhibited a near-Newtonian fluid behavior. It is possible that these above changes are a result of random cleavage of the decrosslinking and the backbone of PGPS, resulting in the preservation of its primary structure. The results will provide a fundamental basis for orientation design and process control of ultrasonic degradation of PGPS.


Subject(s)
Molecular Weight , Plant Gums , Polysaccharides , Prunus persica , Polysaccharides/chemistry , Plant Gums/chemistry , Viscosity , Prunus persica/chemistry , Ultrasonics , Solubility
9.
BMC Public Health ; 24(1): 864, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38509510

ABSTRACT

BACKGROUND: Cost-related medication nonadherence (CRN) is associated with poor prognosis among patients with chronic obstructive pulmonary disease (COPD), a population that requires long-term treatment for secondary prevention. In this study, we aimed to estimate the prevalence and sociodemographic characteristics of CRN in individuals with COPD in the US. METHODS: In a nationally representative survey of US adults in the National Health Interview Survey (2013-2020), we identified individuals aged ≥18 years with a self-reported history of COPD. Cross-sectional study. RESULTS: Of the 15,928 surveyed individuals, a weighted 18.56% (2.39 million) reported experiencing CRN, including 12.50% (1.61 million) missing doses, 13.30% (1.72 million) taking lower than prescribed doses, and 15.74% (2.03 million) delaying filling prescriptions to save costs. Factors including age < 65 years, female sex, low family income, lack of health insurance, and multimorbidity were associated with CRN. CONCLUSIONS: In the US, one in six adults with COPD reported CRN. The influencing factors of CRN are multifaceted and necessitating more rigorous research. Targeted interventions based on the identified influencing factors in this study are recommended to enhance medication adherence among COPD patients.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Adult , Humans , Female , United States/epidemiology , Adolescent , Aged , Cross-Sectional Studies , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/epidemiology , Surveys and Questionnaires , Insurance, Health , Medication Adherence
10.
Int J Biol Macromol ; 262(Pt 2): 130028, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38340927

ABSTRACT

Porous morphology and mechanical properties determine the applications of cryogels. To understand the influence of the ionic network on the microstructure and mechanical properties of pectin cryogels, we prepared low-methoxyl pectin (LMP) cryogels with different Ca2+ concentrations (measured as R-value, ranging from 0 to 2) through freeze-drying (FD). Results showed that the R-values appeared to be crucial parameters that impact the pore morphology and mechanical characteristics of cryogels. It is achieved by altering the network stability and water state properties of the cryogel precursor. Cryogel precursors with a saturated R-value (R = 1) produced a low pore diameter (0.12 mm) microstructure, obtaining the highest crispness (15.00 ± 1.85) and hardness (maximum positive force and area measuring 2.36 ± 0.31 N and 12.30 ± 1.57 N·s respectively). Hardness showed a negative correlation with Ca2+ concentration when R ≤ 1 (-0.89), and a similar correlation with the porosity of the gel network when R ≥ 1 (-0.80). Given the impacts of crosslinking on the pore structure, it is confirmed that the pore diameter can be designed between 56.24 and 153.58 µm by controlling R-value in the range of 0-2.


Subject(s)
Cryogels , Pectins , Cryogels/chemistry , Mechanical Phenomena , Porosity , Hardness
11.
J Food Sci ; 89(2): 1127-1142, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38193192

ABSTRACT

Superfine grinding (SG), as an innovative technology, was conducted to improve the physicochemical and structural properties of fruit pulps. Nectarine, apple, and honey peach were selected as the materials. With the increase in SG frequency, the soluble solids content, viscosity, D[4, 3], D[3, 2], G' and G″ of fruit pulps were evidently decreased, whereas the turbidity was increased. The smallest D[4, 3] (294.90 µm) and D[3, 2] (159.67 µm) were observed in nectarine pulp under SG at 50 Hz. The highest turbidity (266.33) was shown in honey peach pulp under SG at 50 Hz. The active groups of the fruit pulps with SG were exposed by Fourier transform infrared spectroscopy (FT-IR). Notably, the excessive destruction in structure was confirmed in SG with 50 Hz. With soy protein isolate (SPI) addition, D[4, 3] and D[3, 2] of complexes decreased, whereas G' and G″ increased. The formation of new fruit pulp-SPI complexes was demonstrated by FT-IR and LF-NMR analysis. The dense and uniform structure was found in complexes prepared by SPI and fruit pulp with 30 Hz SG. Especially, apple-SPI complex with 30 Hz SG showed the highest water-holding capacity (WHC) (0.75) and adhesiveness (7973.00 g s). A significant correlation between fruit pulps and the complexes was revealed. Taken together, the impact of SG modification on fruit pulps would enhance WHC, rheology, and textural properties of the fruit pulp-SPI complexes, especially for SG with 30 Hz. PRACTICAL APPLICATION: This research provided a comprehensive exploration of the potential of SG technology to modify fruit pulps, solving the diversity of textural customization problems and offering valuable insights for the development of semisolid food products.


Subject(s)
Malus , Prunus persica , Soybean Proteins/chemistry , Fruit/chemistry , Spectroscopy, Fourier Transform Infrared , Viscosity , Allergens/analysis
12.
Food Chem ; 439: 138105, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38043287

ABSTRACT

Non-volatiles offer some insight into the formation of aroma-active components in peach puree (PP), but more depth investigation is still needed. Formation pathways of key aroma-active and off-flavor components in PP during thermal concentration (PP + C) and sterilization (PP + C + S) are unclear. Therefore, GC-O-MS combined with UPLC-MS/MS was used to identify the volatile and nonvolatile components and their formation pathways. Among the 36 aroma-active compounds, the contents of γ-decalactone, hexyl acetate, leaf acetate, hexanal, and 1-hexanol (odor activity value ≥ 1) decreased by 46 %, 100 %, 100 %, 92 %, and 100 % between PP and PP + C + S, causing the weakening of "green" and "fruity" attributes. Off-flavor components including 1-octen-3-one, isobutyric acid, isothiazole, and isovaleric acid were identified during thermal processing. 1-Octen-3-one content increased by 75 % from PP to PP + C + S through linolenic acid metabolism, which contributed to "cooked"; the formation of isobutyric and isovaleric acids, isothiazole, resulted in the enhancement of "sour/rancid" via serine and leucine metabolism.


Subject(s)
Prunus persica , Volatile Organic Compounds , Odorants/analysis , Prunus persica/metabolism , Chromatography, Liquid , Tandem Mass Spectrometry , Acetates , Volatile Organic Compounds/metabolism
13.
Food Chem ; 440: 138236, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38142552

ABSTRACT

To investigate the influence of sugar structure on the quality of peach chips produced using osmotic dehydration (OD) in combination with instant controlled pressure drop (DIC) drying, erythritol, glucose, maltose, and trehalose were selected as osmotic agents. The properties of the osmotic solutions, as well as the macro- and micro-texture, water distribution, and thermal stability of peach chips were investigated. Results showed that OD pretreatments inhibited the formation of large cavity structures. The highest hardness (101.34 N) and the lowest hydrophobicity (0°) were obtained in erythritol-OD samples. Trehalose-OD samples with the most homogeneous pore structure exhibited the highest crispness (1.05 mm) and the highest glass transition temperature (52.06 °C). Various absorption peaks of peach chips pretreated with different OD methods, characterized by Raman spectroscopy, suggested changes in composition and functional groups due to the diffusion of sugars into the cells of peach tissues, which also contributed to the higher Tg.


Subject(s)
Prunus persica , Water , Trehalose/chemistry , Prunus persica/chemistry , Desiccation/methods , Osmosis , Erythritol
14.
Int J Biol Macromol ; 253(Pt 8): 127515, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37865353

ABSTRACT

Pectic polysaccharides modulate gut fermentation ability, which is determined by structural characteristics. In this work, apple pectins were extracted by HCl (HAEP), NaOH (AEP), cellulase (EAEP), and in parallel cell wall pectic fractions were sequentially extracted by water (WEP), chelator (CEP) and NaOH (NEP). The aim is to comprehensively compare the impact of extraction on pectin structure and gut fermentation behavior. Results showed that high content of galacturonic acid (90.65 mol%) and large molecular weight (675 kg/mol) were detected in the HAEP. Molecular morphology of the HAEP presented high linearity, while AEP, EAEP and WEP exhibited compact filamentous structures with highly branched patterns. The AEP was characterized by high yield (33.1 g/100 g d.b.), moderate molecular weight (304 kg/mol) and large extent of rhamnogalacturonan-I region (24.88 %) with low degree of branching (1.77). After in vitro simulated gut fermentation for 24 h, total content of short-chain fatty acid (SCFA) generated with the AEP supplement increased to 36.8 mmol/L, followed by EAEP, HAEP and WEP (25.2, 24.2 and 20.3 mmol/L, respectively). Meanwhile, WEP simultaneously produced the highest ammonia content (22.4 mmol/L). This investigation suggests that the fermentation of AEP produces more beneficial SCFA and less ammonia, thus indicating a better gut fermentation property.


Subject(s)
Ammonia , Pectins , Fermentation , Ammonia/metabolism , Sodium Hydroxide , Pectins/chemistry , Polysaccharides/chemistry , Fatty Acids, Volatile/metabolism , Cell Wall/chemistry
15.
Food Chem ; 428: 136758, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37413836

ABSTRACT

The ice crystal morphology formed under a series of amidated pectin gels with various crosslink strengths were investigated. The results showed that as the degree of amidation (DA) increased, pectin chains exhibited shorter homogalacturonan (HG) regions. Highly amidated pectin exhibited a faster gelation rate and a stronger gel micro-network via hydrogen bonds. Based on cryogenic scanning electron microscopy (cryo-SEM), smaller ice crystals were formed in frozen gel with low DA, suggesting that a weaker cross-linked gel micro-network was more effective at inhibiting crystallization. After sublimation, lyophilized gel scaffolds with high crosslink strength displayed less number of pores, high porosity, lower specific surface area, and greater mechanical strength. This study is expected to confirm that the microstructure and mechanical properties of freeze-dried pectin porous materials could be regulated by changing the crosslink strength of pectin chains, which is achieved by increasing the degree of amidation in the HG domains.


Subject(s)
Ice , Pectins , Crystallization , Gels/chemistry , Pectins/chemistry
16.
Ann Allergy Asthma Immunol ; 131(5): 606-613.e5, 2023 11.
Article in English | MEDLINE | ID: mdl-37499864

ABSTRACT

BACKGROUND: Asthma is a chronic disease that needs long-term control for secondary prevention. Health-related expenditures resulting from asthma are rising in the United States, and medication nonadherence is associated with adverse health outcomes in patients with asthma. OBJECTIVE: To estimate the prevalence and risk factors of cost-related medication nonadherence (CRN) in individuals with asthma in the United States. METHODS: We identified patients aged above or equal to 18 years with a history of asthma in nationally representative cross-sectional data, the National Health Interview Survey 2013 to 2020. Participants were considered to have experienced CRN if at any time in the 12 months they reported skipping doses, taking less medication, or delaying filling a prescription to save money. The weighted prevalence of CRN was estimated overall and by subgroups. Logistic regression was used to identify CRN-related characteristics. RESULTS: Of the 26,539 National Health Interview Survey participants with a history of asthma, 4360 (15.77%; representing 3.92 million of the US population) reported CRN, with 10.12% (weighted 2.51 million) of patients skipping doses to save money, 10.82% (weighted 2.69 million) taking less medication to save money, and 13.35% (weighted 3.31 million) delaying filling a prescription to save money. The subgroups young, women, low income, no health insurance, currently smoking, and with comorbidities had a higher prevalence of CRN. The results of this sensitivity analysis did not differ from the overall results. CONCLUSION: In the United States, 1 in 6 adults with a history of asthma is nonadherence with medications due to costs. Removing financial barriers to accessing medication can improve medication adherence in patients with asthma.


Subject(s)
Asthma , Health Expenditures , Humans , Adult , Female , United States/epidemiology , Aged , Cross-Sectional Studies , Surveys and Questionnaires , Medication Adherence , Asthma/drug therapy , Asthma/epidemiology
17.
Int J Biol Macromol ; 244: 125410, 2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37327923

ABSTRACT

To emphasize that differences in pectin structure among cultivars play a crucial role in the texture and quality of fruits and vegetables, the sugar content and methyl-esterification of pectin fractions from 13 apple cultivars was studied. Cell wall polysaccharides were isolated as alcohol-insoluble solids (AIS) and subsequently extracted to yield water-soluble solids (WSS) and chelating-soluble solids (ChSS). All fractions contained significant amounts of galacturonic acid, while sugar compositions varied between cultivars. AIS and WSS pectins showed a degree of methyl-esterification (DM) > 50 %, while ChSS pectins had either a medium (∼50 %) or low (<30 %) DM. Homogalacturonan as major structure was studied using enzymatic fingerprinting. Methyl-ester distribution of pectin was described by degrees of blockiness and -hydrolysis. Novel descriptive parameters were obtained by measuring the levels of methyl-esterified oligomers released by endo-PG (DBPGme) and PL (DBPLme). Pectin fractions differed in relative amounts of non-, moderately-, and highly methyl-esterified segments. WSS pectins were mostly lacking non-esterified GalA sequences, while ChSS pectins had medium DM and many non-methyl-esterified blocks or a low DM with many intermediate methyl-esterified GalA blocks. These findings will be of help to better understand physicochemical properties of apple and its products.


Subject(s)
Malus , Pectins/chemistry , Polysaccharides/analysis , Fruit/chemistry , Sugars/analysis
18.
Food Res Int ; 170: 113050, 2023 08.
Article in English | MEDLINE | ID: mdl-37316031

ABSTRACT

Changes in carotenoids and volatiles (including ß-carotene-metabolites) of freeze-dried carrots (FDC) treated by thermal/nonthermal-ultrasound (40 KHz, 10 min) and ascorbic (2%, w/v)-CaCl2 (1%, w/v) solution ((H)UAA-CaCl2) during a 120-day storage period were investigated. The results of HS-SPME/GC-MS showed that caryophyllene was the dominant volatile compound (70.80-275.74 µg/g, d.b) in FDC, and 144 volatile compounds were detected in 6 samples. Besides, 23 volatile compounds were significantly correlated with ß-carotene content (p < 0.05), and ß-carotene degraded to off-flavor compounds (ß-ionone: 22.85-117.26 µg/g, ß-cyclocitral: 0-113.84 µg/g and dihydroactindiolide: 4.04-128.37 µg/g) that had adverse effects on FDC flavor. However, UAA-CaCl2 effectively preserved the total carotenoid content (793.37 µg/g), and HUAA-CaCl2 reduced the off-odors (such as ß-cyclocitral and isothymol) formation at the end of storage. These results indicated that (H)UAA-CaCl2 treatments were conducive to the maintenance of carotenoids and the flavor quality of FDC.


Subject(s)
Carotenoids , Daucus carota , beta Carotene , Calcium Chloride
19.
J Texture Stud ; 54(5): 775-786, 2023 10.
Article in English | MEDLINE | ID: mdl-37248614

ABSTRACT

The influence of cell morphology on the textural characteristic of freeze-dried apple, strawberry, and mango cubes was evaluated. Corresponding restructured cube samples without intact cell morphology were prepared as controls. Results indicated that the presence of cell morphology strengthened the shrinkage and collapse of samples during freeze-drying, especially in mangoes due to the high content of sugar. Intact cell morphology was found in natural fruit cubes after freeze-drying by scanning electron microscopy (SEM) observation, making them exhibit a more regular microporous structure, further resulting in higher hardness than the restructured cubes. However, the intact cell morphology negatively affected the crispness of freeze-dried cubes since it enhanced structural collapse. The freeze-dried samples without cell morphology would destroy the cellulose structure and form a continuous open-pore structure under the concentration effect of ice crystals during freezing, which accelerates the escape of water molecules, increases the drying rate, and avoid collapse. Sensory experiments found that restructured cubes without intact cell morphology exhibited greater comprehensive acceptance, suggesting the potential application of cell morphology disruption in the future freeze-drying industry.


Subject(s)
Fragaria , Freeze Drying , Malus , Mangifera , Plant Cells , Fragaria/chemistry , Fragaria/ultrastructure , Freeze Drying/methods , Fruit/chemistry , Fruit/ultrastructure , Malus/chemistry , Malus/ultrastructure , Mangifera/chemistry , Mangifera/ultrastructure , Plant Cells/chemistry , Plant Cells/ultrastructure , Microscopy, Electrochemical, Scanning
20.
J Texture Stud ; 54(5): 763-774, 2023 10.
Article in English | MEDLINE | ID: mdl-37222133

ABSTRACT

Freeze-dried (FD) fruit and vegetable materials with a large amount of sugar are unstable. With the aim to understand the structure formation of FD products, the effects of fructose content on the texture and microstructure of FD matrix were investigated by using pectin-cellulose cryogel model. Cryogels containing fructose of 0-40% were produced using freeze-drying at three different primary drying temperatures of -40, -20, and 20°C. The resultant cryogels were characterized by texture profile analyzer, scanning electron microscope, and µCT. Results indicated that at drying temperature of -40°C, increasing fructose concentration promoted the hardness of the cryogels, and cryogels of 16% fructose obtained maximum hardness. Excessive fructose (≥20%) weakened the described hardness, while exhibiting stronger springiness and resilience. The microstructure showed that dense pores and increased wall thickness due to fructose aggregation were critical factors responsible for increased hardness. The porous structure as well as relatively large pore size were necessary for crispness, in addition, rigid pore wall with certain strength were also required. At the drying temperature of 20°C, large hetero-cavities dominated the microstructure of cryogels with 30% and 40% fructose, caused by melting inside during FD process. In this situation, lower Tm (-15.48 and -20.37°C) were responsible for cryogels' melting In conclusion, if possible, regulating fructose content and state may enable the precision texture design of FD fruit and vegetable foods.


Subject(s)
Cryogels , Fructose , Cryogels/chemistry , Cellulose , Freezing , Pectins
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