Comparation sensory characteristic, non-volatile compounds, volatile compounds and antioxidant activity of MRPs by novel gradient temperature-elevating and traditional isothermal methods

Abstract

A novel gradient temperature-elevating Maillard reaction was developed to effectively produce light-colored MRPs. The main purpose of the present study was to compare the color, taste characteristic, non-volatile compounds, volatile compounds and antioxidant activity of MRPs prepared by the novel gradient temperature-elevating and traditional isothermal methods. The product prepared from soybean peptide, Dxylose and L-cysteine by gradient temperature-elevating method was termed MRP-60. Isothermal method was used to produce light and dark colored MRP, called PXC and PX, respectively. MRP-60 has not only the lowest brown intensity (A420, 0.088), also the highest overall acceptability taste from sensory evaluation. MRP-60 showed the lowest bitterness which could be attributed to the lowest content of bitter amino acids (1.48 mg/ml); MRP-60 also showed indistinctive mouthfulness compared with PXC which elucidated by the percentage of compounds with a molecular weight of 1,000-5,000 Da (15.03 %) and high antioxidant activity. Then, the MRPs prepared by gradient temperature-elevating method successfully attain desirable taste and high antioxidant activity.

Effect of Temperature on Flavor Compounds and Sensory Characteristics of Maillard Reaction Products Derived from Mushroom Hydrolysate

“…Additionally, there was only one sulfur containing compound, 2-methyl-5-propyl-thiophene (0.76 ng/g) in MRP100, which was less than half of its concentration in MRP125 (2.17 ng/g). These results might be due to the fact that higher temperature contributes to the thermal degradation of cysteine and carbonyl compounds, forming volatile compounds with sulfur and nitrogen groups in the final products [ 20 ]. Furthermore, 2-ethyl-6-methylpyrazine was the major nitrogen containing compound and its concentration increased dramatically from 0.93 ng/g at 120 °C to 8.31 ng/g at 130 °C.…”

“…These results were in agreement with umami properties obtained from sensory evaluation. Moreover, it was reported that hydrophobic amino acids including Ser, His, Arg, Val, Met, Phe, Ile and Leu were related to bitterness in products, and among them, Arg, His and Met had a stronger bitter perception [ 16 , 20 ]. Though, the concentration of these bitter taste amino acids in MRP125 was 2.89 mg/mL, higher than those in MH (1.26 mg/mL), however, the content of free amino acids related to bitterness in MRP125 was reduced to 46.03% from 54.40% in MH due to the increase of total free amino acids content after Maillard reaction.…”

“…Though, the concentration of these bitter taste amino acids in MRP125 was 2.89 mg/mL, higher than those in MH (1.26 mg/mL), however, the content of free amino acids related to bitterness in MRP125 was reduced to 46.03% from 54.40% in MH due to the increase of total free amino acids content after Maillard reaction. The high concentration of bitter amino acids does not necessarily result in the bitter taste in food since the overall taste is mostly determined by the balance of various non-volatile compounds other than single component [ 20 ]. This could explain why MRP125 had a lower bitterness score than MH when perceived by panelists.…”

“…On the other hand, different parameters such as temperature, pH, reaction time, and reactants concentration significantly affect the production of MRPs in terms of chemical composition and sensory properties. Thus, different studies have been carried out to determine favorable parameters and precursors in order to enhance the sensory characteristics of MRPs [ 3 , 5 , 19 , 20 ]. The reaction temperature is the most important parameter which affects the reaction rate and antioxidant capacity of MRPs [ 21 ]; also, the thermal treatment can produce MRPs with carcinogenic compounds, such as acrylamide, furans and furan analogues, all of which have negative health effects and should be taken into consideration [ 22 ].…”

Comparison of anti-browning ability and characteristics of the fractionated Maillard reaction products with different polarities

“…The free radical scavenging capacities of the MRPs fractions were determined using DPPH• according to the method of Huang et al (2015) with some modification. The free scavenging capacities of the MRPs and ascorbic acid were determined using DPPH•.…”