The fate of phenolics, soysaponins, major isoflavones and antioxidant activity in soy milk by-product during conventional drying process

Black rice and black rice flour is a food product which is very beneficial for the body, because it contains antioxidants. Antioxidant contained in black rice and black rice flour analyzed by examining the antioxidant activity. The purpose of this study is to determine changes to the antioxidant activity of black rice and black rice flour. The research method is using experimental with 2 samples (black rice and black rice flour). In the Data analysis is using independent t test. The results indicate that there are the differences between the antioxidant activity of black rice and black rice flour. It can be concluded that the drying process in the manufacture of black rice flour lowered antioxidant activity in black rice products.

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Supercritical CO2 drying of food matrices

Proceedings of 21th International Drying Symposium ◽

10.4995/ids2018.2018.7753 ◽

2018 ◽

Author(s):

S. Spilimbergo ◽

A. Zambon ◽

T. M. Vizzotto ◽

G. Morbiato ◽

M. Toffoletto ◽

...

Keyword(s):

Supercritical Co2 ◽

Supercritical Drying ◽

Microbial Inactivation ◽

Process Conditions ◽

Drying Methods ◽

Drying Process ◽

Promising Alternative ◽

Supercritical Co2 Drying ◽

Conventional Drying ◽

Drying Efficiency

This work explore the use of supercritical CO2 drying as alternative technique for the obtainment of pasteurized and high quality dried product. Several tests were conducted on animal, vegetable and fruit matrixes in order to investigate the effectiveness of SC-CO2 drying process at different process conditions. Design of experiment was performed to find the optimal process conditions for vegetable and fruit matrices, using the final water activity of the products as key indicator for the drying efficiency. The inactivation of naturally present microorganisms and inoculated pathogens demonstrated the capability of SC-CO2 drying process to assure a safe product. Moreover, retention of nutrients was compared with conventional drying methods. Results suggest that supercritical drying is a promising alternative technology for food drying. Keywords: supercritical drying; carbon dioxide; food drying; microbial inactivation

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ANTIOXIDANT ACTIVITIES OF HYDROLYSATES ORIGINATED FROM SOYBEAN AND SOY MILK RESIDUE

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/55/5a/12188 ◽

2018 ◽

Vol 55 (5A) ◽

pp. 134

Author(s):

Ngo Minh Ngoc

Keyword(s):

Antioxidant Activity ◽

Protein Content ◽

Manufacturing Industry ◽

Antioxidant Activities ◽

Proteolytic Enzymes ◽

Radical Scavenging ◽

Soy Milk ◽

Dpph Radical ◽

Ic50 Value ◽

Ic50 Values

Soybean (Glycine max) and soy milk residue (okara) are protein-rich materials. Soybean possesses the highest protein content among different types of beans (protein content of soybean varies from 40–42 %). Soy milk residue, a by-product of the soy milk manufacturing industry, contains approximately 27 % protein (by dry weight). A number of recent studies have investigated the improvement of functional properties of protein contained in soybean and okara by fermentation or by the use of proteolytic enzymes. The aim of this study was to evaluate the antioxidant activities of soybean and okara hydrolysates obtained by the fermentation with Aspergillus oryzae or by using proteolytic enzymes (neutrase and flavourzyme). DPPH radical scavenging assay was used to determine the antioxidant activities of hydrolysates. The concentration of peptides required to scavenge DPPH radical by 50 % (IC50 value) was used to evaluate the antioxidant activity of peptides produced obtained from hydrolysates. The results showed that when fermented with A. oryzae, the okara hydrolysate had higher antioxidant activity than the soybean hydrolysate, with IC50 values of 0.447 mg/ml and 3.95 mg/ml, respectively. The hydrolyzed okara obtained from hydrolysis using Neutrase had higher antioxidant activity than the one obtained from hydrolysis using Flavourzyme, with IC50 values of0.200 mg/ml and 0.407 mg/ml, respectively. Different peptide fractions obtained from the hydrolysates using cut-off membrane (10 kDa, 3 kDa and 1 kDa) possessed different antioxidant activities. The < 1 kDa peptide fraction exhibited the highest antioxidant activity with an IC50 value of 0.158 mg/ml.

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Effects of the drying process on the fatty acid content, phenolic profile, tocopherols and antioxidant activity of baru almonds (Dipteryx alata Vog.)

Grasas y Aceites ◽

10.3989/gya.1170182 ◽

2020 ◽

Vol 71 (1) ◽

pp. 343

Author(s):

M. L.L. Campidelli ◽

J. D.S. Carneiro ◽

E. C. Souza ◽

M. L. Magalhães ◽

E. E.C. Nunes ◽

...

Keyword(s):

Fatty Acids ◽

Antioxidant Activity ◽

Vitamin C ◽

Fatty Acid Content ◽

Monounsaturated Fatty Acids ◽

Coumaric Acid ◽

Drying Process ◽

Phenolic Profile ◽

Dipteryx Alata

This study carried out a chromatographic and spectrophotometric characterization of the bioactive compounds, antioxidants, phenolics, tocopherols, sterols and fatty acids of baru almonds “in natura” and submitted to drying processes. It was determined that baru “in natura” almonds presented high levels of phenolic compounds, vitamin C, antioxidants, phenolics, sterols, total monounsaturated fatty acids and low thrombogenic, and atherogenic indexes. During the process of drying it at 65 °C for 30 minutes, a decrease was noted in the levels of caffeic acid, chlorogenic acid, anthocyanins, p-coumaric acid, ferulic acid, o-coumaric acid, quercetin, and polyunsaturated fatty acids. The same condition resulted in an increase in the levels of gallic acid, rutin, catechin, trans-cinnamic acid, vanillin, m-coumaric acid, tocopherols, monounsaturated fatty acids and antioxidant activity (ORAC and DPPH). When submitted to a temperature of 105 ºC for 30 minutes the same behavior was seen with a reduction in the vitamin C and ORAC contents and increased presence of flavonoids.

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Effect of Vacuum Impregnation with Apple-Pear Juice on Content of Bioactive Compounds and Antioxidant Activity of Dried Chokeberry Fruit

Foods ◽

10.3390/foods9010108 ◽

2020 ◽

Vol 9 (1) ◽

pp. 108

Author(s):

Agnieszka Nawirska-Olszańska ◽

Marta Pasławska ◽

Bogdan Stępień ◽

Maciej Oziembłowski ◽

Kinga Sala ◽

...

Keyword(s):

Antioxidant Activity ◽

Water Activity ◽

Bioactive Compounds ◽

Polyphenolic Compounds ◽

Vacuum Pressure ◽

Vacuum Impregnation ◽

Drying Process ◽

Vacuum Technology ◽

Pear Juice ◽

Positive Effect

Food technology seeks ways to preserve products while maintaining high bioactive properties. Therefore, an attempt was made to assess the effect of the process of impregnation with apple-pear juice and the drying process on the content of bioactive compounds in chokeberry fruit. Chokeberry fruits were subjected to impregnation with apple-pear juice at three levels of vacuum pressure, 4, 6, and 8 kPa; then, they were dried using microwave-vacuum technology. The water activity of the obtained products, the content of fructose, glucose, sorbitol, and polyphenolic compounds, and antioxidant activity were determined. A total of 20 polyphenolic compounds were identified in the fruits and the obtained products (seven anthocyanins, six flavonols, four phenolic acids, and three flavan-3-ols). Preliminary processing, which consisted of introducing the juice ingredients into tissue of the chokeberry fruit, resulted in increased content of bioactive compounds. Moreover, a positive effect of impregnation on the antioxidant stability of the fruit after drying was noted. Water activity in the obtained products showed their microbiological safety. Impregnation at 4 kPa vacuum pressure proved to be the most desirable; in such conditions, the best product in terms of the content of bioactive compounds was obtained.

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Effect of Dehydration on Several Physico-Chemical Properties and the Antioxidant Activity of Leeks (Allium porrum L.)

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha3915861 ◽

2011 ◽

Vol 39 (1) ◽

pp. 144 ◽

Cited By ~ 4

Author(s):

Mehmet OZGUR ◽

Arzu AKPINAR-BAYIZIT ◽

Tulay OZCAN ◽

Lutfiye YILMAZ-ERSAN

Keyword(s):

Antioxidant Activity ◽

Dry Matter ◽

Chemical Properties ◽

Effect Of Temperature ◽

Allium Porrum ◽

Drying Process ◽

Hot Air Drying ◽

Air Drying ◽

Hot Air ◽

Physico Chemical

This study investigated the changes in some physico-chemical properties and variations in antioxidant compounds of leeks (cv. ‘Inegol-92’) caused by the drying process. The dry matter and ash contents of the fresh leek samples were 8.06 and 0.58 g 100 g-1, respectively. The pH of the fresh leek samples was 6.02, and the titritable acidity in terms of citric acid was 0.14%. As expected, application of hot-air drying significantly increased the dry matter and ash values due to removal of water from the leek slices. The rehydration ratio of dried leeks at 45°C was 5.41, and the coefficient of rehydration was 0.47. The contents of chlorophyll a and b were higher in the dried leeks than in the fresh leeks. The dehydrated leeks showed a high total color difference (?E=12.53) mainly due to the effect of temperature on heat-sensitive compounds. As expected, both fresh and dried leek samples exhibited antioxidant activity with fresh leeks showing a higher capacity of antioxidant activity. Drying the leeks resulted in some ascorbic acid loss. Fresh leeks had much higher phenolic values (26.33 mg rutin eq 100 g DM-1) than the dehydrated samples. The antioxidant capacity of leeks was decreased by more than 50% during the drying process. Although being the most applied method of thermal dehydration, hot air drying causes the degradation of sensitive components, which results in significant losses in sensorial and physico-chemical properties of the dried products.

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