A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t) (min), solvent (methanol) concentration (S) (v/v) and microwave power level (MP) for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g−1 dry weight (dw) was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g−1 dw), caffeic acid (1.33 mg g−1 dw), ferulic acid (0.50 mg g−1 dw) max contents were obtained at S of 100%, t of 15 min, and MP of 10%, while the max chlorogenic acid content (1.35 mg g−1 dw) was obtained at S of 100%, t of 5 min, and MP of 10%. The radical scavenging activity of the extract was evaluated by using the DPPH assay and optimum antioxidant activity was obtained at S of 100%, t of 5 min, and MP of 10%.

With the turn of this century, novel food processing techniques have become commercially very important because of their profound advantages over the traditional methods. These novel processing methods tend to preserve the characteristic properties of food including their organoleptic and nutritional qualities better when compared with the conventional food processing methods. During the same period of time, there is a clear rise in the populations suffering from food allergies, especially infants and children. Though, this fact is widely attributed to the changing livelihood of population in both developed and developing nations and to the introduction of new food habits with advent of novel foods and new processing techniques, their complete role is still uncertain. Under the circumstance, it is very important to understand the structural changes in the protein as food is processed to comprehend whether the specific processing technique (conventional and novel) is increasing or mitigating the allergenicity. Various modern means are now being employed to understand the conformational changes in the protein which can affect the allergenicity. In this review, the processing effects on protein structure and allergenicity are discussed along with the insinuations of recent studies and techniques for establishing a platform to investigate future pathway to reduce or eliminate allergenicity in the population.

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The molecular dynamic (MD) modeling approach was applied to evaluate the effect of an external electric field on soybean hydrophobic protein and surface properties. Nominal electric field strengths of 0.002 V/nm and 0.004 V/nm had no major effect on the structure and surface properties of the protein isolate but the higher electric field strength of 3 V/nm significantly affected the protein conformation and solvent accessible surface area. The response of protein isolate to various external field stresses demonstrated that it is necessary to gain insight into protein dynamics under electromagnetic fields in order to be able to develop the techniques utilizing them for food processing and other biological applications.

This review presents an overview of the application of molecular dynamic simulation to study food proteins. Processing of food using thermal, chemical, radiation, electromagnetic, and mechanical techniques is subject to its macromolecular bio-components such as carbohydrates and proteins to extreme heat, ionic strength, pH, and mechanical deformation. These processing factors affect protein's functional properties such as emulsification, dough formation, gelation, etc., which are associated with changes in their structure. It is difficult to study the structural changes of protein during processing using standard methods like Circular dichroism, Nuclear Magnetic Resonance (NMR), and X-ray diffraction. Hence, in this manuscript application of molecular dynamic simulation to visualize and analyze the protein dynamics during processing has been evaluated. Effect of external stresses such as hydration, temperature, and electric field on protein structure have been analyzed and related mechanisms are explained. The response of food proteins to these stresses demonstrated that it is necessary to gain insight into protein dynamics to be able to develop novel and/or modify existing food processing techniques to improve the overall nutritional and organoleptic qualities of processed food products.

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Soymilk is lower in calories compared to cow’s milk, since it is derived from a plant source (no cholesterol) and is an excellent source of protein. Despite the beneficial factors, soymilk is considered as one of the most controversial foods in the world. It contains serine protease inhibitors which lower its nutritional value and digestibility. Processing techniques for the elimination of trypsin inhibitors and lipoxygenase, which have shorter processing time and lower production costs are required for the large-scale manufacturing of soymilk. In this study, the suitable conditions of time and temperature are optimized during microwave processing to obtain soymilk with maximum digestibility with inactivation of trypsin inhibitors, in comparison to the conventional thermal treatment. The microwave processing conditions at a frequency of 2.45 GHz and temperatures of 70 °C, 85 °C and 100 °C for 2, 5 and 8 min were investigated and were compared to conventional thermal treatments at the same temperature for 10, 20 and 30 min. Response surface methodology is used to design and optimize the experimental conditions. Thermal processing was able to increase digestibility by 7% (microwave) and 11% (conventional) compared to control, while trypsin inhibitor activity reduced to 1% in microwave processing and 3% in conventional thermal treatment when compared to 10% in raw soybean.

This study evaluated the effect of the thermal and high electric field stresses on the secondary structure conformation of peanut protein using Fourier transform infrared spectroscopy. The amide I region between the wavelengths 1700-1600 cm-1 of the spectra were studied for different thermal and high electric field treatments. Within thermal treatments, both hot air roasting and microwave processing treatments were evaluated. Hot air treatments were performed at temperatures of 50, 75, and 100°C from 15, 30, and 45 min while the microwave treatments were conducted at the same temperatures, but for 5, 10, 15, and 20 min. Three experimental conditions were evaluated for the electric field intensity of 10, 15, and 20 kV for 60, 120, and 180 min. Changes were observed at 1654-1650 cm-1 , indicating conformational changes in the α-helix secondary structure. Similar changes were observed at various other wavelengths indicating changes in the 3/10 helix, β-sheets and random coils present in the protein. With an increase in the treatment time, the secondary structure reorganizations increased with the creation of new random coils and aggregated strands. Curve-fitting using Gaussian band shapes further supported the observations. In vitro protein digestibility studies were also performed and the protein changes also supported the observations from the spectra.