Quality Characteristics of Vegan Mayonnaise Produced Using Supercritical Carbon Dioxide-Processed Defatted Soybean Flour.

Emulsifiers, like egg yolk (EY), are necessary for the formation of mayonnaise, which is an oil-in-water type of colloid. This study aimed to assess the potential of defatted soybean powder treated with supercritical carbon dioxide (DSF) to enhance the quality of plant-based mayonnaise as plant-based alternatives gain popularity. This study involved the production of DSF and the comparison of its quality attributes to those of mayonnaise made with varying amounts of control soy flour (CSF), DSF, and EY. It was found that mayonnaise made with an increased quantity of DSF showed better emulsion stability, viscosity, and a smaller, more uniform particle size when compared with CSF mayonnaise. Additionally, DSF mayonnaise was generally rated higher in sensory evaluation. The addition of approximately 2% DSF positively influenced the emulsion and sensory properties of the vegan mayonnaise, indicating that DSF is a promising plant-based alternative emulsifier for the replacement of animal ingredients.

Effect of different vacuum levels for beef brisket during cold storage: A microbiological and physicochemical analysis.

Effect of packaging at different vacuum levels such as 7.2 Pa (99.99% vacuum), 30 kPa (70.39%), 70 kPa (30.91%), and 101.33 kPa (0%, atmospheric condition) using a specially designed airtight container on physicochemical and microbial properties of beef brisket cuts during cold storage was investigated. Dramatic pH increase was found only in air atmospheric packaging. Higher vacuum level yielded higher water holding capacity and lower volatile basic nitrogen (VBN), 2-thiobarbituric acid (TBA), and growth rate of aerobic bacteria and coliforms, whereas the fatty acid composition showed no difference among various vacuum levels. The highest vacuum level (7.2 Pa) yielded no increases in VBN, TBA, and coliform and the least increase in aerobe counts. For bacterial communities, higher vacuum levels yielded higher proportions of Leuconostoc, Carnobacterium, and lactobacilli belonging to the phylum Firmicutes and lower proportions of Pseudomonas belonging to the phylum Proteobacteria. Predictive curves for bacterial communities showed that just a little oxygen significantly affects the bacterial dominance based on different oxygen dependence of individual bacteria and their logarithmic changes by vacuum level.

Miyeokgui (Undaria pinnatifida Sporophyll) Characteristic under Different Relative Humidity: Microbial Safety, Antioxidant Activity, Ascorbic Acid, Fucoxanthin, α-/ß-/γ-Tocopherol Contents.

This study aimed to investigate the effects of different relative humidities (%) on the microbial safety, antioxidant activity, ascorbic acid, fucoxanthin, and tocopherol contents of Undaria pinnatifida sporophyll powder (UPSP) stored for 4 weeks. The caking phenomenon did not occur in the 11-53% relative humidity conditions, but it did in the 69%, 81%, and 93% relative humidity conditions with caking index values of 88.30%, 99.75%, and 99.98%, respectively. The aerobic bacterial contents increased drastically in samples stored at 69-93% relative humidity. Ascorbic acid was unstable at high relative humidity, but fucoxanthin and tocopherol were more unstable at low relative humidity. Therefore, it was most stable at intermediate relative humidity. The 69% relative humidity sample had higher DPPH (12.57 g BHAE/kg), ABTS (4.87 g AAE/kg), and FRAP (4.60 g Fe (II)/kg) than the other samples. This study could be helpful for the storage and transport of UPSP under optimum relative humidity conditions, which can significantly prevent quality losses.

Effect of Heating under Different Vacuum Levels on Physicochemical and Oxidative Properties of Beef Sirloin.

The physicochemical and oxidative properties of beef sirloin slices heated under atmospheric (101.33 kPa, a vacuum percent of 0%, control) and vacuum (50.8 kPa, 50% and 7.2 Pa, 99.99%) conditions by using an airtight vacuum container were compared. Heating at a higher vacuum level resulted in the lowest pH and cooking loss compared with the other conditions (p < 0.05). The beef in vacuum groups was less hard, chewy, and gummy than the control group, without any significant differences between the vacuum groups. More structural shrinkage and lower browning were observed in the meat heated at higher vacuum levels. Similarly, higher vacuum levels suppressed increases in the lightness (L*), redness (a*), and total color difference (E*) of the surface after heating. The thiobarbituric acid (TBA) values, a sensitive indicator of meat oxidation due to heating, were only influenced by the vacuum conditions. Consequently, applying a vacuum effectively prevents the degradation in the meat's physicochemical and oxidative properties during heating. The findings are useful for the sous-vide industry because they scientifically demonstrate how vacuum pressure affects the physicochemical and oxidative properties of the meat by using a specially designed airtight vacuum container.

Phospholipids molecular species, proteins secondary structure, and emulsion microstructure of egg yolk with reduced polar and/or nonpolar lipids.

This study investigated the phospholipids (PLs) molecular species (PLs-MS), protein secondary structure (PSS), and emulsion microstructure of the egg yolk (EY) treated with supercritical-CO2 (T1), hexane (T2), and ethanol {at room temperature (T3) and 65 °C (T4)}. PLs-MS, PSS, and microstructure of EY emulsion were investigated with UPLC-Q-TOF-MS, Fourier-transforms infrared and Raman spectroscopy, and confocal laser scanning microscope, respectively. Predominant PLs molecular fractions were C18:0-C20:4, C18:0-C20:4, C16:0-C18:2, C16:0, C18:0-C18:2, and d18:1/16:0, for phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, lysophosphatidylcholine, sphingomyelin, and phosphatidylserine, respectively. All the PLs-MS were highest for T1 and many of them (C14:0-C16:0, C18:0-C18:1, C18:0-C20:3) were absent in T2, T3, and T4. PSS components (α-helices, ß-sheets, ß-turn, and random coil) were highest for T4, followed by T3, T2, T1, and control (non-treated EY). However, T1-added o/w emulsion showed excellent stability (95.64 %) with smaller and denser oil droplets due to better ionic interactions by synergistic effect of PLs-MS and PSS components.

Phytochemical profile and antioxidant activity of Dracocephalum moldavica L. seed extracts using different extraction methods.

Dracocephalum moldavica L. (DM) is used to treat cardiovascular diseases and dermatitis. However, the properties of DM seed and its extracts remain unclear. We analyzed the bioactive compounds and antioxidant activity of aqueous extract (AE), ethanolic extract (EE), and supercritical CO2 extracted oil (SC-oil) of DM seed. Alpha-linolenic acid was the most abundant fatty acid (51.4-61.6%) with an ω-3 to ω-6 ratio of 2.93-3.42 to 1. Stigmasterol and ß-sitosterol + fucosterol were the main components of DM seed extracts, and campesterol was detected only in SC-oil. The total tocopherol content, especially γ-tocopherol, was 60% higher in EE than in AE and SC-oil, whereas ß-carotene was detected only in SC-oil. The content of total phenols and flavonoids was the highest in EE. Rosmarinic acid, apigenin, and caffeic acid were detected only in EE. The radical scavenging activity of EE was the highest in EE. The results can help promote DM application.

Thermal processing under oxygen-free condition of blueberry puree: Effect on anthocyanin, ascorbic acid, antioxidant activity, and enzyme activities.

The effect of thermal treatment of blueberry was investigated using a designed grinding and continuous packaging system under oxygen-free conditions. The grinding, packaging, and heating at 90 °C for 30 min under anaerobic condition were compared to heating under aerobic conditions, showing complete inactivation of oxidative enzymes. Heating without oxygen retained anthocyanins and ascorbic acid whereas heating in atmospheric air does not. Delphinidin glycoside was mostly influenced by oxygen deficiency during heating, followed by petunidin and malvidin glycosides. The differences in oxygen sensitivity may be closely associated with the number of hydroxylation in the B ring. The result of anthocyanin led to higher antioxidant activity and redness values of purees heated without oxygen than purees heated with oxygen. Consequently, thermal processing under oxygen-free condition can prevent oxidation of anthocyanin, resulting in higher retention of color and nutritional values of blueberry products.

Effect of storage temperature on the antioxidant activity and catechins stability of Matcha (Camellia sinensis).

This study was conducted to evaluate the storage conditions of matcha (Camellia sinensis) according to temperature during 2 months. The moisture content of matcha tend to decrease with increasing temperature. To evaluate the brightness and green value of matcha, changes in L* and G* values were examined. These values decreased with increasing temperature and time. Total phenolic content and total flavonoid content also decreased with increasing temperature and time. ABTS and DPPH radical scavenging activities decreased with the increase in storage temperature and time. The content of catechins such as epicatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate showed a tendency to decrease gradually according to the storage temperature and time. Also, caffeine and rutin content in matcha significantly decreased according to storage temperature and time. This study could be used as basic data to determine optimal storage conditions by measuring physiological changes according to the temperature conditions of matcha.

Quality changes in perilla seed powder related to storage duration and temperature.

Perilla seed powder (PSP) was stored at 25 °C, 35 °C, and 45 °C for 8 weeks. Changes in the metabolite profiles of the powders, including fatty acids, were monitored. Correlations between these changes and quality parameters, including lipid oxidation, color, and antioxidant activity, were analyzed to evaluate the effects of storage duration and temperature on PSP quality. Acid values increased significantly with the duration of storage, but not with temperature. Multivariate statistical analysis was performed to identify differences among the metabolite profiles. The PSP sample stored for 1 week at 45 °C and all samples stored at 25 °C and 35 °C were grouped separately from the control and samples stored at 45 °C for more than 4 weeks. Among the many metabolites associated with these differences, lysophosphatidylethanolamines, tocopherol, sitosterol, tryptophan, 12-hydroxyjasmonic acid glucoside, and maltose correlated negatively with quality parameters with the exception of L* and antioxidant activity. Luteolin, apigenin, luteolin 4'-methyl ester, citric acid, isocitric acid, 9(S)-HPODE, and 3,5-octadien-2-one correlated positively with quality. Although the quantities of some antioxidants and lipids decreased during storage, the results suggested that the quality of PSP samples stored at 25 °C, 35 °C, and 45 °C for 8 weeks was acceptable. This was because lipid oxidation promoted by the storage environment was limited by antioxidants in the samples. These metabolites could be useful for monitoring changes in PSP quality.

Anaerobic Degradation of [14C]Methiozolin under Aquatic Sediment Conditions.

The fate of methiozolin under anaerobic conditions was investigated in clay loam with a high organic carbon content and sandy loam with a low carbon content using [dihydroisoxazole ring-14C] and [phenyl-14C] radiolabels. The sediment/water ratio was 1:3 based on the dry weight:volume (w/v) ratio; the incubations lasted up to 355 days after the treatment (DAT) and were performed in the dark at 20.4 ± 0.7 °C. The overlying water flow-through systems consisted of glass vessels containing sediment with traps for [14C]carbon dioxide and [14C]volatiles. The samples were collected and analyzed at 0, 3, 7, 14, 50, 100, 200, and 355 DAT. The water and sediment samples were extracted with solvent systems, centrifuged, concentrated, and analyzed by liquid scintillation counting and a high-performance liquid chromatography (HPLC) system equipped with a flow scintillation analyzer. Following extraction, the sediments were air-dried, and the subsamples were combusted. [14C]Methiozolin was degraded in the water phase and partitioned rapidly into the sediments, where it was further degraded to other metabolites, which were identified by HPLC and liquid chromatography- or gas chromatography-tandem mass spectrometry (MS/MS) with authentic standards. The dissipation of methiozolin from the overlying water was rapid (with half-lives of 1.1-1.8 and 3.6-4.9 days in the clay loam and sandy loam, respectively). However, methiozolin dissipation from the sediment phase and the whole system was much slower than from the water phase (with half-lives of 122.0-220.0 and 110.0-130.0 days in the sediment phase of the clay loam and sandy loam and 116.0-166.0 and 70.8-85.7 days in the whole system of the clay loam and sandy loam, respectively).

Physicochemical properties, sensory traits and storage stability of reduced-fat frankfurters formulated by replacing beef tallow with defatted bovine heart.

The consumer interests for low-fat meat products are increasing to reduce obesity and chronic diseases. Reduced-fat frankfurter (RFF) was prepared by replacing beef tallow with defatted bovine heart (DBH) produced by supercritical-CO2 (SC-CO2) and hexane. Six different frankfurters i.e. control (20% beef fat), T1 (30% fat replacement with non-defatted bovine heart), T2 and T3 (20% and 30%, respectively, fat replacement with SC-CO2-treated DBH), T4 and T5 (20% and 30%, respectively, fat replacement with hexane-treated DBH), were formulated. Physicochemical properties, sensory traits and storage stability of the control and RFFs were investigated. T3 had highest native proteins (18.50 g/100 g) resulting in increased viscosity, emulsion stability, hardness and redness (a⁎) with lowest energy value and cooking loss. T2 showed better sensory attributes than the control and other RFFs. Incorporation of SC-CO2-treated DBH in frankfurter by replacing fat led to higher oxidative stability and lower microbial content during storage than the control, T1, T4 and T5.

Thermal and functional characteristics of defatted bovine heart using supercritical CO2 and organic solvent.

BACKGROUND: Consumer demand for low-fat foods has been increasing as a result of attempts to reduce obesity and chronic diseases. Bovine heart was defatted using supercritical CO2 (SC-CO2 ) at different pressures together with solvent extraction to produce a protein-based functional ingredient for low-fat food products. Thermal and functional characteristics of control and defatted samples were compared. RESULTS: Supercritical CO2 treatment at high pressure results in more removal of fat, producing a protein-rich defatted bovine heart (DBH). The differential scanning calorimeter (DSC) thermograms and SDS-PAGE bands for SC-CO2 -treated DBHs were similar to those of the control sample, indicating high protein stability and better functionality. Hexane-treated DBH showed no major thermal peaks and very diffuse bands in SDS-PAGE, indicating denaturation of proteins during solvent extraction. No denaturation of proteins in SC-CO2 -treated DBHs resulted in significantly higher water/oil absorption capacities (3320.00 and 2630.00 g kg-1 , respectively), total soluble solids (822.20 and 208.71 g kg-1 at pH 3.5 and 6.5, respectively), foaming capacities (149.37%), and emulsion activity (66.89%) than the hexane-treated DBH. CONCLUSION: Supercritical CO2 treatment of DBH led to higher thermal stability and functional properties than the control and hexane-treated DBH. Defatted bovine heart using SC-CO2 can be a functional ingredient for various low-fat and high-protein food products for health-conscious consumers. © 2018 Society of Chemical Industry.

Perilla Oil Decreases Aortic and Hepatic Lipid Accumulation by Modulating Lipogenesis and Lipolysis in High-Fat Diet-Fed Mice.

Perilla oil has been shown to be beneficial for ameliorating metabolic disorders, but its protective effect is still controversial. We investigated the effect of perilla oil on obesity-induced hepatic and vascular changes in high-fat diet (HFD)-fed mice and provided underlying mechanisms for potential therapeutic applications. Tomato and paprika extract was added to prevent the oxidation during storage of perilla oil. HFD-fed mice were orally administered palm or perilla oil for 90 days. Food intake, body and liver weight, and serum cholesterol levels were measured. Arterial and hepatic lipid accumulation was determined by histological staining. Hepatic triglyceride levels and the expression of proteins regulating lipid metabolism were analyzed. Food intake and body weight were not different between palm oil-treated and perilla oil-treated mice. Serum cholesterol level was significantly lower in perilla oil-treated mice compared with palm oil-treated mice. HFD-induced lipid accumulation was also lower in thoracic aorta and liver by perilla oil compared with palm oil. Perilla oil also decreased hepatic triglyceride level without changing the liver weight. Perilla oil treatment increased the AMP-activated protein kinase and acetyl-CoA carboxylase phosphorylation and the lipolytic protein levels, whereas it decreased the lipogenic protein levels in the liver. In conclusion, perilla oil reduced serum cholesterol and arterial and hepatic lipid accumulation in HFD-fed mice. The data suggest that perilla oil improves the balance of lipogenic and lipolytic protein expression, and ameliorates obesity-induced metabolic disorders and cardiovascular diseases.

The Effects of Added Water and Grinding Temperature on Stability and Degradation Kinetics of Antioxidant Activity, Phenolic Compounds, and Ascorbic Acid in Ground Apples.

The effects of added water (1:0 up to 1:4 apple:water w/v) and grinding temperature on browning and antioxidant capacity of apples were investigated. Grinding apple with addition of water decreased browning and loss of antioxidant activity when ground with water up to 1:3 ratio. Browning, antioxidant capacity, major phenolic compounds (chlorogenic acid, epicatechin, and procyanidin B2), and ascorbic acid in ground apple with water (1:1) were evaluated at grinding temperatures from 5 °C to 45 °C. The degradation of antioxidant activity, phenolic compounds, and ascorbic acid followed first-order kinetics. The temperature-dependent degradation was adequately modeled using the Arrhenius equation, and kinetic parameters such as k, t1/2 , Q10 , and Ea indicated that the grinding temperature was a key factor affecting retention of antioxidant activity, phenolics, and ascorbic acid contents in apple. PRACTICAL APPLICATION: The phenolic compounds and antioxidant activity of fruits and vegetables can be altered by processing such as thermal treatments and grinding. Therefore, it is important to evaluate and predict the quality characteristics of the fruits as affected by processing conditions. In this study, we found grinding conditions retard the changes in color and loss in phenolic compounds and antioxidant activity of ground apples. This new finding can be helpful for engineers and scientists to control and optimize the grinding system by retaining the high nutritional values of apple products.

Yield and physicochemical properties of low fat tofu prepared using supercritical carbon dioxide treated soy flours with different fat levels.

The consumer demands for low fat foods are increasing to reduce obesity and chronic diseases. Low-fat tofu (LFT) was prepared using soy flours treated with supercritical CO2 (SC-CO2) at pressures of 10, 20, and 30 MPa. After SC-CO2 treatment, the residual oil contents of the soy flours were 12.07, 8.12, and 1.64%, respectively, whereas that of the control soy flour was 18.20%. The objective of this study was to investigate the yield and quality characteristics of LFTs, compared to the control tofu. All SC-CO2-treated LFTs had significantly higher protein and moisture contents than the control tofu. The yields (g/100 g soy flour) of SC-CO2-treated tofu were 442.69, 507.44, and 535.47 g, respectively, at three fat levels, whereas the yield was 385.23 g in case of the control tofu. The SC-CO2-treated LFTs had softer textural attributes due to increasing moisture contents. In addition, the LFTs obtained higher sensory scores owing to softer texture and lower beany flavor than control sample. SC-CO2-treated soy flours showed higher solubility in soy milk, leading to higher yield, produced softer texture of tofu, and increased nutritional value with low fat and high protein content.

Anti-amyloidogenic properties of an ethyl acetate fraction from Actinidia arguta in Aß1-42-induced ICR mice.

This study aimed to investigate the ameliorating effect of an ethyl acetate fraction from the fruit Actinidia arguta (EFAA) on amyloid beta (Aß)-induced neurotoxicity and cognitive deficits in ICR mice. EFAA showed potent protective effects against Aß-induced neurotoxicity through 2',7'-dichlorofluorescein diacetate (DCF-DA), 2',3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) release into the assay medium. EFAA treatment reduced the intracellular ROS level and lactate dehydrogenase (LDH) release in the mitochondria, and increased cell viability in Aß-induced neuroblastoma MC-IXC cells. The administration of EFAA significantly attenuated Aß-induced learning and memory deficits, which were evaluated by Y-maze, passive avoidance, and Morris water maze tests. Furthermore, EFAA showed the ameliorating effect of cholinergic functions by increasing acetylcholine (ACh) levels and decreasing acetylcholinesterase (AChE) activity, and protected antioxidant systems by increasing superoxide dismutase (SOD) and decreasing the oxidized glutathione (GSH)/total GSH and malondialdehyde (MDA) in the brain. Finally, EFAA prevented mitochondrial dysfunction via regulating apoptotic signaling molecules including phosphorylated Akt (p-Akt), phosphorylated tau (p-tau), Bax, and cytochrome c in the brain tissues. Therefore, the present study suggests that EFAA might be a potential source of natural antioxidants with the ability to ameliorate Aß-induced amnesia.

Effect of Grinding at Modified Atmosphere or Vacuum on Browning, Antioxidant Capacities, and Oxidative Enzyme Activities of Apple.

This study evaluated the effects of grinding at atmospheric pressure (control), under vacuum (∼2.67 kPa), or with modified atmosphere (N2 and CO2 ) on the browning, antioxidant activity, phenolics, and oxidative enzyme activity of apples as a function of time. The control group was affected most, showing distinct browning and losing most of the antioxidant activity and concentrations of the main phenolic compounds. The modified atmosphere groups retained color, antioxidant activity, and phenolic compounds better than the control group. Least changes were obtained with vacuum grinding, particularly in terms of preventing enzymatic browning and oxidation of antioxidants apples. At 12 h after grinding, vacuum-ground apples retained total phenolic contents 5.32, 1.54, and 1.49 times higher than control, nitrogen gas, and carbon dioxide gas-ground samples, respectively. The oxidative enzyme activity, including that of polyphenol oxidase and peroxidase, decreased in the control and modified atmosphere group, but they were maintained in the samples ground under the vacuum. PRACTICAL APPLICATION: In this study, we found that grinding with modified atmosphere or vacuum conditions could effectively prevent browning as well as loss of phenolic compounds and antioxidant activity of ground apples. These results can help scientists and engineers build better grinding systems for retaining nutrient and quality factors of ground apples. In addition, these results may be useful to other fruit and vegetable industries that wish to retain fresh-like quality and nutritional value during grinding and storage.

Comparative study of the quality characteristics of defatted soy flour treated by supercritical carbon dioxide and organic solvent.

Defatted soy flour is a potential source of food protein, amino acids, ash and isoflavones. The supercritical carbon dioxide (SC-CO2) and a traditional organic solvent extraction methods were used to remove fat from soy flour, and the quality characteristics of a control soy flour (CSF), defatted soy flour by SC-CO2 (DSFSC-CO2) and defatted soy flour by an organic solvent (DSF-OS) were compared. The SC-CO2 process was carried out at a constant temperature of 45 °C, and a pressure of 40 MPa for 3 h with a CO2 flow rate of 30 g/min. The DSFSC-CO2 had significantly higher protein, ash, and amino acids content than CSF and DSF-OS. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated that CSF and DSFSC-CO2 had protein bands of similar intensity and area that indicated no denaturation of protein, whereas DSF-OS showed diffuse bands or no bands due to protein denaturation. In addition to higher nutritional value and protein contents, DSFSC-CO2 showed superior functional properties in terms of total soluble solids content, water and oil absorption, emulsifying and foaming capacity. The SC-CO2 method offers a nutritionally and environmentally friendly alternative extraction processing approach for the removal of oil from high-protein food sources. It has a great potential for producing high-protein fat-free, and low-calorie content diet than the traditional organic solvent extraction method.

Nutritional Quality and Physicochemical Characteristics of Defatted Bovine Liver Treated by Supercritical Carbon Dioxide and Organic Solvent.

Defatted bovine liver (DBL) is a potential source of protein and minerals. Supercritical carbon dioxide (SC-CO2) and a traditional organic solvent method were used to remove lipid from bovine liver, and the quality characteristics of a control bovine liver (CBL), bovine liver defatted by SC-CO2 (DBLSC-CO2) at different pressures, and bovine liver defatted by organic solvent (DBL-OS) were compared. The DBLSC-CO2 samples had significantly higher (p<0.05) protein, amino acid, carbohydrate, and fiber contents than CBL and DBL-OS. There was a higher yield of lipid from CBL when using SC-CO2 than the organic solvent method. SDS-PAGE analysis demonstrated that the CBL and DBLSC-CO2 had protein bands of a similar intensity and area, whereas DBL-OS appeared extremely poor bands or no bands due to the degradation of proteins, particularly in the 50 to 75 kDa and 20 to 25 kDa molecular weight ranges. In addition, DBLSC-CO2 was shown to have superior functional properties in terms of total soluble content, water and oil absorption, and foaming and emulsification properties. Therefore, SC-CO2 treatment offers a nutritionally and environmentally friendly approach for the removal of lipid from high protein food sources. In addition, SC-CO2 may be a better substitute of traditional organic solvent extraction for producing more stable and high quality foods with high-protein, fat-free, and low calorie contents.

The effect of grinding at various vacuum levels on the color, phenolics, and antioxidant properties of apple.

The purpose of this study was to evaluate the effect of grinding at different vacuum levels (2.67, 6.67, 13.33, 19.99, and 101.33kPa) on key quality factors of apple. In the control apple, ground at atmospheric pressure of 101.33kPa, the antioxidant activities rapidly decreased within the first 30min, then plateaued thereafter, while enzymatic browning increased. When apples were ground and held under vacuum, changes in color and antioxidant activity were much less, and the least change was measured in samples prepared at the lowest pressure. Model fitting of the data showed that antioxidant activity decreased as a function of the logarithm of the absolute pressure. The results from analysis for key phenolic compounds including chlorogenic acid, procyanidin B2, and epicatechin indicated that these compounds were least changed at vacuum grinding at 2.67kPa, compared to atmospheric grinding.