Stability and expression of K-ras mimotopes in freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder during storage in vacuum packaging.

AIMS: This study aims to evaluate the storage stability of the freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder expressing K-ras (Kristen rat sarcoma viral oncogene homolog) mimotopes targeting colorectal cancer in vacuum packaging. METHODS AND RESULTS: The freeze-dried L. lactis-fermented milk powder stored in 4-ply retortable polypropylene (RCPP)-polyamide (PA)-aluminium (AL)-polyethylene terephthalate (PET) and aluminium polyethylene (ALPE) was evaluated throughout 49 days of accelerated storage (38°C and 90% relative humidity). The fermented milk powder stored in 4-ply packaging remained above 6 log10 CFU g-1 viability, displayed lower moisture content (6.1%), higher flowability (43° angle of repose), water solubility (62%), and survivability of L. lactis after simulated gastric and intestinal digestion (>82%) than ALPE packaging after 42 days of accelerated storage. K-ras mimotope expression was detected intracellularly and extracellularly in the freeze-dried L. lactis-fermented milk powder upon storage. CONCLUSIONS: This suggests that fermented milk powder is a suitable food carrier for this live oral vaccine.

Microencapsulated polyphenol extracts from Georgia-grown pomegranate peels delay lipid oxidation in salad dressing during accelerated and ambient storage conditions.

Lipid oxidation is a major cause of quality deterioration in salad dressings. This study evaluated the effect of incorporating microencapsulated polyphenol extracts via spray drying from pomegranate peels (MPP) to delay lipid oxidation in Italian-style salad dressings (ISD) during accelerated (55°C) and ambient (25°C) storage conditions. ISDs, prepared at high (5000 rpm) and low (250 rpm) shear rates conditions, were formulated with unencapsulated polyphenol extracts from pomegranate peels (PPP), MPP, and/or grape seed extract (GSE). Lipid oxidation in ISDs was evaluated by measuring peroxide value (PV), iodine value (IV), and TBARS, stored in accelerated and ambient conditions for 21 days and 8 weeks, respectively. Tannis in extracts were measured via HPLC-DAD and the total hydrolyzable tannin content of PPP and MPP was 283.09 and 427.74 (mg/g extract), respectively. Condensed tannins were not detected in PPP and MPP but were found in GSE (348.53 mg/g extract). Salad dressings prepared at high shear rates had significantly (p < .05) higher emulsion stability than those homogenized at low shear rates. Mixing conditions did not affect the lipid oxidative stability of IDSs. Salad dressing stored under accelerated storage had higher lipid oxidation (higher PV, lower IV, and higher TBARS) after 21 days than IDSs stored under ambient conditions for 8 weeks. ISDs prepared with MPPP showed significantly (p < .05) lower lipid oxidation than the other ISDs at the end of the shelf life studies. Results from the accelerated storage suggested that incorporating MPP could have extended the shelf life of IDSs by 20% compared to using unencapsulated polyphenol extracts. The study demonstrated that MPP delays lipid oxidation in ISDs during storage more effectively than unencapsulated extracts. MPP may serve as a natural and effective functional food ingredient for controlling lipid oxidation in high-lipid and acidified foods.

Antibacterial and antibiofilm effects of Camellia oleifera seed dreg extract and its application in cosmetics.

BACKGROUND: Cosmetic care products contain a high proportion of water and nutrients. Therefore, preventing bacterial growth is an important issue to ensure product quality and safety. The application of antibacterial natural ingredients derived from plants is considered to have the potential to maintain product quality and reduce the use of chemicals in formulations. Additionally, chemically synthesized antiseptic and antibacterial agents are widely used in the industry at present. However, some preservative ingredients have been reported that may cause skin irritation, redness, allergies, and even dermatitis. AIMS: This study aimed to prepare extract from Camellia oleifera tea seed dregs (CTSD), investigate the antibacterial effects on two pathogenic bacteria and evaluate the product preservative ability. METHODS: Ethanol extraction was prepared and subjected to characterize their triterpenoid contents. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum biofilm eradication concentration (MBEC) were determined for Pseudomonas aeruginosa and Staphylococcus aureus. The product's stability and preservative qualities, along with its ability to scavenge free radicals through antioxidant activity, were also assessed. RESULTS: The gram-positive S. aureus showed greater susceptibility to the treatment. In additional, CTSD possessed significant free radical scavenging activity in vitro and cultured normal human skin fibroblast CCD-966SK cells under nontoxic concentration. The challenge test and accelerated storage test confirmed the CTSD containing formulated emulsion is eligible for commercialization. CONCLUSIONS: CTSD has the potential to be developed as an alternative agent to control microbial biofilm formation, or can be used as an adjuvant compound for infectious disease control.

Characterization and Mechanism of Gel Deterioration of Egg Yolk Powder during Storage.

Egg yolk forms have several health and industrial applications, but their storage characteristics and gel mechanisms have not been thoroughly studied. In order to investigate the relationship between the changes in structure and properties of egg yolk gel and egg yolk powder during storage, in this paper, egg yolk powder was stored at 37 °C for 0, 1, 3, and 6 months in an accelerated storage experiment, and the influence of storage time on the gel properties of egg yolk powder was analyzed. The results showed that the contents of protein carbonylation and sulfhydryl in the yolk decreased gradually with the extension of storage time. Circular dichroism and fluorescence spectra showed that the ordered structure and structural stability of egg yolk proteins decreased gradually. Oxidation led to the formation of intermolecular crosslinking in the egg yolk proteins and oxidized aggregates, resulting in a decrease in surface hydrophobicity, which affected the gel properties of the egg yolk powder after rehydration, resulting in the phenomenon of lipid migration and gel degradation. The results provide a theoretical basis for improving egg yolk powder's overall quality and storage stability.

Effects of Non-Enzymatic Browning and Lipid Oxidation on Color of Ready-to-Eat Abalone during Accelerated Storage and Its Control.

The deepening of color of ready-to-eat (RTE) abalone during storage leads to sensory quality degradation, which seriously affects the shelf life of products and consumers' purchasing desire. The goal of this study is to look into the causes of non-enzymatic browning and lipid oxidation, as well as how to control them, and their effect on the color of RTE abalone during storage. The control, bloodletting and antioxidants groups (lactic acid, citric acid and 4-hexylresorcinol) of RTE abalone were stored for 0, 20 and 40 days at 40 °C, respectively, to explore the rule and mechanism of the color change in RTE abalone. This research shows that RTE abalone undergoes browning during storage. Meanwhile, the content of reducing sugar, phenols and unsaturated fatty acids decreases, while the formation of lipid hydroperoxides and aldehydes increases during storage. In addition, the color change in RTE abalone during storage is mainly related to the Maillard reaction, while the lipid oxidation mainly forms pyrrole and participates in the Strecker degradation process as part of the Maillard reaction. The quality of RTE abalone can be maintained by controlling browning effectively as well as lipid oxidation through bloodletting and the addition of antioxidants to ensure that RTE abalone has high storage stability. According to our research, bloodletting and the addition of antioxidants to RTE abalone have a good application prospect and popularizing value in the storage of RTE abalone.

Simultaneous analysis of the oxidation of solvent-extracted and cold-pressed green coffee oil during accelerated storage using 1H NMR and 13C NMR spectroscopy.

Green coffee oil (GCO) extracted from green coffee beans, is known for its antioxidant and anticancer properties, and has been increasingly utilised in cosmetic and other consumer products. However, lipid oxidation of GCO fatty acid components during storage may be harmful to human health, and there remains a need to understand the evolution of GCO chemical component oxidation. In this study, proton nuclear magnetic resonance (1H and 13C NMR) spectroscopy was used to investigate the oxidation status of solvent-extracted and cold-pressed GCO under accelerated storage conditions. Results show that the signal intensity of oxidation products gradually increased with increasing oxidation time, while unsaturated fatty acid signals gradually weakened. Five different types of GCO extracts were clustered according to their properties, except for minor overlapping in the two-dimensional plane of the principal component analysis. Partial least squares-least analysis results demonstrate that oxidation products (δ = 7.8-10.3 ppm), unsaturated fatty acids (δ = 5.28-5.42 ppm), and linoleic acid (δ = 2.70-2.85 ppm) in 1H NMR can be used as characteristic indicators of GCO oxidation levels. Furthermore, the kinetics curves of unsaturated fatty acids, linoleic, and linolenic acyl groups all fit an exponential equation with high coefficients of GCO for 36 days under accelerated storage conditions. Our results show that the current NMR system is a fast, easy-operated and convenient tool for the oxidation process monitoring and quality control of GCO.

Lipid Oxidation and Volatile Compounds of Almonds as Affected by Gaseous Chlorine Dioxide Treatment to Reduce Salmonella Populations.

The effects of gaseous chlorine dioxide (ClO2) treatment, applied to inactivate Salmonella, on lipid oxidation, volatile compounds, and chlorate levels of dehulled almonds were evaluated during a 3 month accelerated storage at 39 °C. At treatment levels that yielded a 2.91 log reduction of Salmonella, ClO2 promoted lipid oxidation as indicated by increased peroxide values, total acid number, conjugated dienes, and thiobarbituric acid-reactive substances. Furthermore, several chlorine-containing volatile compounds including trichloromethane, 1-chloro-2-propanol, 1,1,1-trichloro-2-propanol, and 1,3-dichloro-2-propanol were identified in ClO2-treated samples. However, all the volatile chlorine-containing compounds decreased during the 3 months of storage. Chlorate (26.4 ± 5.1 µg/g) was found on the ClO2-treated samples. The amounts of non-ethanol alcohols, aldehydes, and carboxylic acids increased following ClO2 treatments. Some volatiles such as 2,3-butanediol that were present in non-treated samples became non-detectable during post-ClO2 treatment storage. Overall, our results demonstrated that gaseous ClO2 treatment promoted lipid oxidation, generation of volatiles of lipid origin, and several chlorine-containing compounds.

Effects of Packaging Materials on Structural and Simulated Digestive Characteristics of Walnut Protein during Accelerated Storage.

Walnuts are rich in fat and proteins that become oxidized during the processing and storage conditions of their kernels. In this study, the effect of three packaging materials (e.g., polyethylene sealed packaging, polyamide/polyethylene vacuum packaging, and polyethylene terephthalate/aluminum foil/polyethylene vacuum packaging) were investigated on the oxidation, structural and digestive properties of walnut kernel proteins. Results showed that the amino acid content gradually decreased and carbonyl derivatives and dityrosine were formed during storage. The protein molecule structure became disordered as the α-helix decreased and the random coil increased. The endogenous fluorescence intensity decreased and the maximum fluorescence value was blue-shifted. After 15 days of storage, surface hydrophobicity decreased, while SDS-PAGE and HPLC indicated the formation of large protein aggregates, leading to a reduction in solubility. By simulating gastrointestinal digestion, we found that oxidation adversely affected the digestive properties of walnut protein isolate and protein digestibility was best for polyethylene terephthalate/aluminum foil/polyethylene vacuum packaging. The degree of protein oxidation in walnuts increased during storage, which showed that except for fat oxidation, the effect of protein oxidation on quality should be considered. The results of the study provided new ideas and methods for walnut quality control.

QTRAP LC/MS/MS of Garlic Nanoparticles and Improving Sunflower Oil Stabilization during Accelerated Shelf Life Storage.

The purpose of this research was to assess and utilize the bioactive compounds of garlic nanoparticles (Ga-NPs) as a natural antioxidant in sunflower oil (SFO) stored at 65 ± 1 °C for 24 days. The garlic nanoparticles (Ga-NPs) from the Balady cultivar were prepared, characterized, and added to SFO at three concentrations: 200, 600, and 1000 ppm (w/v), and they were compared with 600 ppm garlic lyophilized powder extract (Ga-LPE), 200 ppm BHT, 200 ppm α-tocopherol, and SFO without Ga-NPs (control). The QTRAP LC/MS/MS profile of Ga-NPs revealed the presence of four organosulfur compounds. Ga-NPs exhibited the highest capacity for phenolic, flavonoid, and antioxidant compounds. In Ga-NP SFO samples, the values of peroxide, p-anisidine, totox, conjugated dienes, and conjugated trienes were significantly lower than the control. The antioxidant indices of SFO samples containing Ga-NPs were higher than the control. The Ga-NPs enhanced the sensory acceptability of SFO treatments up to day 24 of storage. The shelf life of SFO treated with Ga-NPs was substantially increased (presuming a Q10 amount). The results show that Ga-NPs are a powerful antioxidant that improves SFO stability and extends the shelf life (~384 days at 25 °C).

Investigation on the impact of quality characteristics and storage stability of foxtail millet induced by air cold plasma.

The aim of this work was to investigate the effects of dielectric barrier discharge-air cold plasma (DBD-ACP, 15-35 kV, 2-12 min) on the quality of foxtail millets. The L and b* values were evaluated by a digital colorimeter representing that the color of millets was significantly changed at 25 kV for 4-12 min or at 35 kV for 2-12 min. The results were consistent with the change of total yellow pigment in millets, indicating that DBD-ACP damaged the carotenoids if the treatment condition was too high. The activity of lipoxygenase and lipase, involving the oxidation and hydrolysis of lipids of millet, decreased significantly induced by DBD-ACP. For example, the lipoxygenase and lipase activity of Mizhi millet was decreased from 44.0 to 18.7 U g-1min-1, 56.0-15.1 U/(mg pro) (p<0.05) after being exposed to 25 kV for 2-12 min, respectively. Changes of color, lipoxygenase and lipase activity, and malondialdehyde content of millets were determined during accelerated storage (40 ± 2°C and 75% Relative Humidity) for 15 days after being treated by DBD-ACP under 15 and 25 kV for 4 min. Results showed that millets treated by DBD-ACP at 15 kV kept a better color with lower malondialdehyde content, and lower lipoxygenase and lipase activity compared to control. This work implied that DBD-ACP is an underlying approach for the storage of foxtail millets.

Effects of different antioxidants and their combinations on the oxidative stability of DHA algae oil and walnut oil.

Through monitoring Rancimat induction time (RIT), peroxide value (POV), and thiobarbituric acid-reactive substances (TBARS) of docosahexaenoic acid (DHA) algae oil and walnut oil during accelerated storage, the effects of the single and the combinations of seven kinds of antioxidants involving ascorbyl palmitate (AP), phytic acid (PA), vitamin E (VE), antioxidant of bamboo leaves (AOB), rosemary extract, tea polyphenols (TP), and tea polyphenol palmitate (TPP) against lipid oxidation were evaluated. RIT, POV, and TBARS results showed that the DHA algae oil sample containing 600 mg/kg TPP revealed the strongest stability and the walnut oil sample containing 450 mg/kg TPP and 100 mg/kg TP revealed the strongest stability. Then, the shelf lives of two oils were predicted from the extrapolation of the linear regression model between Log RIT and temperature. Our results indicated that the optimal antioxidant could prolong the shelf lives of DHA algae oil and walnut oil by 2.31- and 7.74-fold, respectively.

Individual and Joint Effect of Alpha-Tocopherol and Hydroxytyrosol Acetate on the Oxidation of Sunflower Oil Submitted to Oxidative Conditions: A Study by Proton Nuclear Magnetic Resonance.

This study tackles the individual and joint effect of alpha-tocopherol and hydroxytyrosol acetate on the oxidation of sunflower oil submitted to accelerated storage conditions at intermediate temperature, in order to deepen the understanding of antioxidant-prooxidant behaviour. This was accomplished by 1H Nuclear Magnetic Resonance. For this purpose, the evolution of the degradation of both the main components of the oil and the aforementioned added compounds was monitored by this technique throughout the storage time. Furthermore, the formation of a very large number of oxylipins and the evolution of their concentration up to a very advanced stage of oil oxidation, as well as the occurrence of lipolysis, were also simultaneously studied. The results obtained show very clearly and thoroughly that in the oxidation process of the oil enriched in binary mixtures, interactions occur between alpha-tocopherol and hydroxytyrosol acetate that notably reduce the antioxidant effect of the latter compound with the corresponding negative consequences that this entails. The methodology used here has proved to be very efficient to evaluate the antioxidant power of mixtures of compounds.

Alpha-Tocopherol, a Powerful Molecule, Leads to the Formation of Oxylipins in Polyunsaturated Oils Differently to the Temperature Increase: A Detailed Study by Proton Nuclear Magnetic Resonance of Walnut Oil Oxidation.

Lipid oxidation causes food degradation and the formation of toxic compounds. Therefore, the addition to foods of compounds able to avoid, delay or minimize this degradative process is a commonly used strategy. Nevertheless, neither the identity of most of the formed compounds in this complex process nor the way in which their formation is affected by the strategy used are well known. In this context, the effect the temperature increase and the enrichment level in alpha-tocopherol on the evolution of the walnut oil oxidation, as a model of an oil rich in polyunsaturated omega-6 acyl groups, submitted to storage conditions, are tackled by 1H NMR. The study has allowed knowing the degradation kinetic of both the oil acyl groups and alpha-tocopherol, the identification of a very high number of oxylipins and the kinetic of their formation. The temperature increase accelerates the formation of all oxylipins, favouring the formation of hydroperoxy conjugated E,E-dienes and related derivatives versus that of the Z,E-isomers. The enrichment in alpha-tocopherol accelerates the formation of hydroperoxy conjugated Z,E-dienes and related derivatives, and delays in relation to the formation of the former that of the E,E-isomers and related derivatives, hindering, to a certain extent, the formation of the latter in line with the enrichment level.

Influence of Hydroxytyrosol Acetate Enrichment of an Oil Rich in Omega-6 Groups on the Evolution of Its Oxidation and Oxylipin Formation When Subjected to Accelerated Storage. A Global Study by Proton Nuclear Magnetic Resonance.

Sunflower oil samples, both unenriched and enriched with four different concentrations of hydroxytyrosol acetate, were subjected to accelerated storage at 70 °C until a very advanced oxidation stage and the process was monitored by 1H NMR spectroscopy. The aim of the study is to know the effect that the presence of this antioxidant has on the oxidation process of sunflower oil under the aforementioned conditions, as well as on the formation and evolution of the concentration of a significant number of oxylipins. The oxidation process was studied globally by monitoring, during storage time, the degradation of both the linoleic acyl group of sunflower oil, which is the main component of sunflower oil, and the added hydroxytyrosol acetate. Simultaneously, the identification of up to twenty-six different types of oxylipins formed in the oxidation process and the monitoring of the evolution of their concentration over the storage time were carried out. In this way, essential information about the effect that hydroxytyrosol acetate provokes on the oxidation of this oil rich in omega-6 polyunsaturated acyl groups, has been obtained. It has also been shown that the enrichment of sunflower oil with this antioxidant under the conditions tested does not prevent the oxidation process but slows it down, affecting the entire oxidation process.

Evaluation of Hemp Seed Oils Stability under Accelerated Storage Test.

The interest in hemp seed oil has recently increased, due to the latest regulations which allow its use as food. Hemp seed oil is characterized by a high content of polyunsaturated fatty acids, which are highly prone to oxidation. Accelerated thermal oxidation (60 °C, 18 days) has been applied to nine types of cold-pressed hemp seed oils to monitor the evolution of the samples during oxidative deterioration. The results showed that the only determinations of primary (peroxide value) and secondary (TBARs) oxidation products did not allow a sufficient or correct evaluation of the oxidative changes of hemp seed oils during storage. In fact, samples at the end of the test were primarily characterized by a high presence of oxidation volatile compounds and a significant decrease of antioxidants. Several volatiles identified before the accelerated storage, such as the predominant α-pinene and ß-pinene, gradually decreased during the accelerated storage period. On the other hand, aldehydes (hexanal, (E)-2-hexenal, heptanal, (E,E)-2,4-hexadienal, (E)-2-heptenal, (E,E)-2,4-heptadienal, (E,Z)-2,4-heptadienal, 2-octenal, nonanal, nonenal, 2,4-nonadienal, (E,E)- 2,4-decadienal and 2,4-decadienal), ketones (1-octen-3-one, 3-octen-2-one, (E,E)-3,5-octadien-2- one and 3,5-octadien-2-one), acids (propionic acid, pentanoic acid, hexanoic acid and heptanoic acid) and 2-pentyl-furan increased during the accelerated storage, as principal markers of oxidation.

Goji Berry (Lycium Barbarum L.) Carotenoids Enrichment through 'Green' Extraction Method Improves Oxidative Stability and Maintains Fatty Acids of Yak Ghee with Microwave Heating and Storage.

As the oxidation of yak ghee is inevitable and as consumer demand for natural products continues to increase, this study aimed to enrich yak ghee with goji berry carotenoids by means of green solvent extraction and determined changes in the oxidative stability and fatty acid profiles of yak ghees during microwave heating (MW-heating) and accelerated storage. An enriched ghee (GG0) was prepared by high shear dispersion and ultrasound-assisted extraction, while a control ghee (FG0) was prepared by heating and filtration; both ghees were stored at 65 °C for 30 days and were microwave-heated (MW-heating) at 180 °C (15 and 30 min) and 200 °C for 30 min. The results showed that the carotenoid enrichment increased the oxidative stability of yak ghee during MW-heating and storage. The initial CLA and PUFA values of GG0 were not significantly different from those of FG0; SFA increased, and MUFA and TFA decreased. There was a faster rate of UFA loss and an increase in SFA and TFA in FG0 during MW-heating and storage. This indicated a protective effect of carotenoid enrichment on yak ghee. Therefore, the findings in this study support the use of goji berry carotenoids as a natural colorant and antioxidant in yak ghee. This study provides vital information for dairy processors and marketers.

Effects of konjac glucomannan on the long-term retrogradation and shelf life of boiled wheat noodles.

BACKGROUND: Starch retrogradation and moisture migration of boiled wheat noodles (BWNs) result in quality deterioration and short shelf life. The objective of this research was to investigate whether konjac glucomannan (KGM) could improve the quality of BWNs and further establish the shelf-life prediction model. RESULTS: The moisture distribution, recrystallization, and thermal properties of BWNs during refrigerated or ambient temperature storage were determined. Low-field nuclear magnetic resonance data showed that KGM addition induced left-shifts of T21 and T22 values, indicating that KGM limited the mobility of bound and immobile water among noodle matrices. X-ray diffraction spectra revealed that KGM did not change the crystal patterns of BWNs but could inhibit the starch recrystallization after refrigerated storage. The Tp and ΔH values of retrograded samples notably (P < 0.05) decreased with the increase of KGM addition, suggesting the hinderance of starch retrogradation behavior by KGM. The shelf life of BWNs was predicted by accelerated storage test combined with the Arrhenius equation. The present data displayed that the predicted shelf life of vacuum-packed and sterilized BWNs with 10 g kg-1 KGM at 25 °C was 733 days, 2.4-fold that of the control group. CONCLUSION: BWNs with KGM addition could inhibit starch retrogradation and improve the storage stability, consequently promoting noodle quality. © 2021 Society of Chemical Industry.

Influence of Anticaking Agents and Storage Conditions on Quality Characteristics of Spray Dried Apricot Powder: Shelf Life Prediction Studies Using Guggenheim-Anderson-de Boer (GAB) Model.

Apricot powder was developed through spray drying using gum arabic as an encapsulating material at a concentration of 19%. Inlet air temperature, feed total soluble solids (TSS), feed flow rate, and atomization speed were 190 °C, 23.0 °C, 300.05 mL/h, and 17,433 rpm, respectively. This study was therefore conducted to investigate the influence of anticaking agents (tricalcium phosphate and silicon dioxide) and storage conditions (ambient and accelerated) on physicochemical, micrometric, and thermal characteristics of spray-dried apricot powder (SDAP) packaged in aluminum laminates. Both tricalcium phosphate (TCP) and silicon dioxide (SiO2) improved the shelf life and quality of SDAP, with TCP being more effective, since a lower increase in water activity (aw), moisture content, degree of caking, hygroscopicity, and rehydration time was observed in TCP-treated samples followed by SiO2-treated samples than the control. Furthermore, flowability, glass transition temperature (Tg), and sticky-point temperature (Ts) of SDAP tended to decrease in a significant manner (p < 0.05) under both storage conditions. However, the rate of decrease was higher during accelerated storage. The water activity of treated samples under ambient conditions did not exceed 0.60 and had a total plate count within the permissible range of 40,000 CFU/g, indicating shelf stability of the powder. The predicted shelf life of powder obtained from the Guggenheim−Anderson−de Boer (GAB) model and experimental values were very similar, with TCP-treated samples having a predicted shelf life of 157 days and 77 days under ambient and accelerated storage conditions, respectively. However, the respective experimental shelf life under the same conditions was 150 and 75 days, respectively. Similarly, the predicted shelf life of SiO2-treated samples under ambient and accelerated storage was 137 and 39 days, respectively, whereas the experimental values were 148 and 47 days, respectively. In conclusion, TCP proved more effective than SiO2 at preserving shelf life by preventing moisture ingress.

Changes in surface chemical composition relating to rehydration properties of spray-dried camel milk powder during accelerated storage.

Alterations in surface chemical composition relating to rehydration properties of spray-dried camel milk powders during accelerated storage (11-33% RH, 37 °C) over 18 weeks were investigated. The results showed that the surface of the fresh spray-dried camel milk powder (t = 0) was dominated by lipids (78%), followed by proteins (16%) and lactose (6%). During storage, the surface protein and lactose content decreased while the surface lipid content increased, resulting in an increase in surface hydrophobicity and slight agglomeration of the powder, especially for powder kept at 33% RH. Although fresh camel milk powder had very poor wettability, it displayed very high dispersibility and solubility (99%). During storage, dispersibility and solubility declined with increasing storage time and increasing RH levels, which correlated with an increase in surface lipid content. However, at the end of the storage period, camel milk powder still retained very high solubility (>93%).

Effects of gallic acid alkyl esters and their combinations with other antioxidants on oxidative stability of DHA algae oil.

The most effective composite antioxidants for DHA algae oil were optimized by combining the selected gallic acid (GA) alkyl ester with other commonly used antioxidants. Results of Rancimat induction time, peroxide value, thiobarbituric acid-reactive substances, and free radical generation indicated that octyl gallate (OG) was the best one in DHA algae oil among GA alkyl esters with various chain lengths. Therefore, OG was used to combine other antioxidants (antioxidant of bamboo leaves, rosemary extract, tea polyphenols, tea polyphenol palmitate (TPP), ascorbyl palmitate, vitamin E, phytic acid and phospholipid) for further improving the oxidative stability of DHA algae oil. The combination of OG + TPP showed the best antioxidant effect among the composite antioxidants of two and three components. Through optimization of mixture ratio, the combination of 53.20 mg/kg OG + 360 mg/kg TPP demonstrated the best antioxidant capacity, which prolonged the shelf life of DHA algae oil by 4.24 folds.