Application of high hydrostatic pressure and ultrasound-assisted extractions as a novel approach for pectin and polyphenols recovery from tomato peel waste

Square wave voltammetry (SWV) analysis was used to assess the antioxidant interactions (synergism, addition, and antagonism) of fruit mixture extracts from grape (G), lemon (L), and blueberry (B) obtained by conventional extraction, ultrasound-assisted extraction, and high hydrostatic pressure extraction. The experimental results showed antagonistic antioxidant effects in all binary mixture extracts (L-G, L-B, and G-B). In DPPH and FRAP assays, the greatest antioxidant capacity was found in the G-B mixture (108.7 and 108.8 μmol TE g−1 dry extract, respectively) obtained by high hydrostatic pressure extraction; however, there were no significant differences when measured by ultrasound-assisted extraction. For TPC and TFC assays, the greatest values were for G-B (6.67 mg GA g−1 dry extract) and L-G (1.63 mg QE g−1 dry extract), respectively. SWV experiments showed antagonistic behavior in the mixtures. Among the different ratios of the fruit mixture extracts evaluated by SWV, 1 : 1 (w/w) combination showed the greatest antagonistic antioxidant effects. SWV suggests the components of the mixture with the highest antioxidant capacity oxidize after mixing. The results indicate that the presence of natural bioactive antioxidants in fruit mixtures does not guarantee that the interactions are synergistic.

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Valorisation Approach for the Soybean By-Product Okara Using High Hydrostatic Pressure

Current Nutrition & Food Science ◽

10.2174/1573401314666180516092837 ◽

2019 ◽

Vol 15 (6) ◽

pp. 548-550 ◽

Cited By ~ 1

Author(s):

Inmaculada Mateos-Aparicio ◽

Elena Pérez-López ◽

Pilar Rupérez

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure ◽

Dietary Fibre ◽

New Technologies ◽

Scale Up ◽

Industrial Transformation ◽

Novel Approach ◽

Soluble Dietary Fibre ◽

Carcinogenic Effects ◽

The Rich

Okara is a perishable, cheap and abundant by-product derived from soybean after extracting the soluble fraction for tofu or soybean drink, mainly known as soymilk, production. Nowadays, Okara is mostly discarded: landfill and incineration, but a useful alternative for valorisation would be to use it as a valuable source of dietary fibre. However, it presents low soluble dietary fibre (SDF) content responsible for prebiotic and anti-carcinogenic effects, so an easy industrial transformation to maximize its SDF content would be most interesting for this purpose. Different approaches can be used to increase SDF content, such as chemical or enzymatic treatments with food-grade enzymes at atmospheric pressure, but these conventional methods present some disadvantages as that the chemical procedures are pollutant and the extractions normally are incomplete, and the enzymatic methods could be expensive to scale-up. On the other hand, currently, consumers are demanding for safer, more natural and minimally-processed foods. This request has led researchers and manufacturers to develop new technologies, and within these, high hydrostatic pressure (HHP) is one of the top-10 most popular emerging technologies applied in the field of food science. The effect of HHP, and more recently, the combined effect of HHP and enzymatic treatment on okara by-product have been studied, showing that this novel approach, should also be considered in order to stabilise other agro-food byproducts -due to their perishable character- as well as to improve the functionality of the rich-ininsoluble dietary fibre from vegetable residues.

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High hydrostatic pressure aided by food-grade enzymes as a novel approach for Okara valorization

Innovative Food Science & Emerging Technologies ◽

10.1016/j.ifset.2017.07.012 ◽

2017 ◽

Vol 42 ◽

pp. 197-203 ◽

Cited By ~ 10

Author(s):

E. Pérez-López ◽

I. Mateos-Aparicio ◽

P. Rupérez

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure ◽

Food Grade ◽

Novel Approach

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Survival of mouse blastocysts after low-temperature preservation under high pressure

Acta Veterinaria Hungarica ◽

10.1556/avet.52.2004.4.10 ◽

2004 ◽

Vol 52 (4) ◽

pp. 479-487 ◽

Cited By ~ 7

Author(s):

Cs. Pribenszky ◽

M. Molnár ◽

S. Cseh ◽

L. Solti

Keyword(s):

Phase Transition ◽

Hydrostatic Pressure ◽

Low Temperature ◽

High Hydrostatic Pressure ◽

Room Temperature ◽

Freezing Point ◽

Significant Loss ◽

Embryo Cryopreservation ◽

Subzero Temperatures ◽

Survival Capacity

Cryoinjuries are almost inevitable during the freezing of embryos. The present study examines the possibility of using high hydrostatic pressure to reduce substantially the freezing point of the embryo-holding solution, in order to preserve embryos at subzero temperatures, thus avoiding all the disadvantages of freezing. The pressure of 210 MPa lowers the phase transition temperature of water to -21°C. According to the results of this study, embryos can survive in high hydrostatic pressure environment at room temperature; the time embryos spend under pressure without significant loss in their survival could be lengthened by gradual decompression. Pressurisation at 0°C significantly reduced the survival capacity of the embryos; gradual decompression had no beneficial effect on survival at that stage. Based on the findings, the use of the phenomena is not applicable in this form, since pressure and low temperature together proved to be lethal to the embryos in these experiments. The application of hydrostatic pressure in embryo cryopreservation requires more detailed research, although the experience gained in this study can be applied usefully in different circumstances.

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