Antioxidant characteristics of non-traditional spicy-aromatic vegetable raw materials for restaurant technology

Introduction. The aim of the study is to determine the antioxidant capacity of non-traditional for restaurant technology spicy-aromatic vegetable raw materials. Materials and methods. Antioxidant capacity of spicy-aromatic plant raw materials: Hyssopus officinalis L. , Dracocephalum moldavica L. , Agastache foeniculum L. , Melissa officinalis L. , Ocimum basilicum L. , Foeniculum vulgare Mill. , Glebionis coronaria L. , Satureja hortensis L. were determined by redoxmetry and pH-metry of water-alcohol infusions; sensory indicators – by expert method; the results of mathematical and statistical processing – by the method of linear Pearson correlation. Results and discussion. The hydrogen index for water-alcohol infusions from spicy-aromatic raw materials has a value of 5.28 units pH ( Hyssopus officinalis L.) to 6.69 units pH ( Agastache foeniculum L. ). The minimum theoretical value of redox potential ( RP ) for plant water-alcohol infusions, which varies from 258.6 mV ( Agastache foeniculum L. ) to 343.2 mV ( Hyssopus officinalis L. ), was obtained. The actual measured RP of infusions was established – from 93 mV ( Hyssopus officinalis L. ) to 148 mV ( Glebionis coronaria L. ). Water-alcohol infusions from plant raw materials and a volume fraction of ethanol of 40% have a value of reduction

These biologically active substances are very sensitive to the conditions of preparation, especially to solventswater (Tülek et al., 2020), ethyl alcohol, water-alcohol mixture (Kuzmin et al., 2020). Therefore, the conditions necessary for the efficient extraction of these compounds are specific to each plant, and this is an important issue in the process of their extraction (Tülek et al., 2020). Despite some achievements, a number of issues remain related to the preparation of spicy-aromatic plant raw materials (Priecina et al., 2018), which has antioxidant capacity. These are rare plant crops in Ukraine that are unconventional for restaurant technology (Kuzmin et al., 2020).
They have gained growing interest among scientists and consumers due to their antioxidant properties (Breiter et al., 2011;Dube et al., 2017. The ability of plant phenolics to act as free radical scavengers has led to increased interest in their ability to act as antioxidants Humia et al., 2020;Keating et al., 2014;Oh et al., 2013). Antioxidants are able to reduce the output of oxidation products: hydroperoxides, alcohols, aldehydes, ketones, fatty acids.
These circumstances determine the relevance of this work, which is to develop wateralcohol extracts of vegetable raw materials in the technology of restaurants. Creating restaurant products with reduced toxicity through the introduction of spicy-aromatic infusions with antioxidant properties, allows restaurant establishments to create new products, which favorably differentiates them from competitors, creating a favorable image of the institution, which cares for the protection of consumers.
The aim of the study is to determine the antioxidant capacity of non-traditional for restaurant technology spicy-aromatic vegetable raw materials.
To achieve this goal, the following research objectives were set: -To confirm the prospect of using non-traditional for restaurant technology spicyaromatic vegetable raw materials; -To establish the value of antioxidant capacity of spicy-aromatic vegetable raw materials; -To carry out the mathematical and statistical analysis of indicators of antioxidant ability of spicy-aromatic vegetable raw materials and to establish internal correlation; -To identify the richest sources of natural antioxidants due to spicy-aromatic plant raw materials for use in restaurant technology; -To investigate the compositions of spicy-aromatic vegetable raw materials for restaurant technology.

Materials
The study used plant raw materials that are allowed to be used in the production of restaurant products. In the M.M. Gryshko National Botanic Garden of NAS of Ukraine was created new cultures of spicy-aromatic plants, which became the subject of these studies (Rakhmetov, 2011).

Description of research procedure
Drying of spicy-aromatic vegetable raw materials was carried out in natural conditions for 6-8 days to constant humiditynot more than 14 %. Collected and inspected raw materials were laid out on clean white paper, each type separately.
The first stagethe preparation of infusions. Plant raw materials were minced into a size of 3x3 mm, suspensions of 4 g were placed into the glass bottles, were filled by 100 ml of alcohol solvent with volume fraction of rectified ethyl alcohol 40 %. The resulting infusions were cooled to 20 °C for 7 days, stirring periodically.
Next, the infusions were filtered and studies were performed to determine the indicators of active acidity, which was measured on a pH meter in the mode of pH measurement with a combined glass electrode. The RP was measured in the potential measurement mode with a combined redoxmetric platinum electrode.

Expert method of sensory evaluation
The expert method of determination of values of indexes of quality is based on the account of opinions of group highly skilled specialists-experts. (The expert of − it a specialist on the certain type of object which owns the increased sensitiveness to properties of this object) (Kuzmin et al., 2016).

Methods for determining antioxidant capacity
RP is an important indicator of the biological activity of solutions (Kuzmin O. et al., 2016;Merwe et al., 2017). It characterizes the deviation from the ionic balance of free electrons in a liquid medium. Changing the concentration of free electrons leads to a change in its electron charge and, accordingly, the RP. If the RP is positive, it indicates the oxidizing ability of the solution, negative indicates recovery ability. The value of RP allows to estimate the energy of processes, that is, characterizes the activity of ions in redox reactions (Bahir, 1999;Priluckij, 1997). Therefore, in order for the human body to optimally use in the exchange processes water-alcohol solutions and food, the RP values must correspond to the RP values of the internal environment of the organism, or have more negative values (Bahir, 1999).
To evaluate the antioxidant properties of the obtained water-alcoholic plant extracts, the method (Priluckij, 1997), based on the difference of RP in inactivated inorganic solutions and complex biochemical media. The main criteria of this method were its clarity, simplicity, specificity, reproducibility of results and efficiency. A number of researchers also emphasize that method allows to determine the total antioxidant activity of liquid products, including in total in a complex mixture, and multifunctional antioxidants (Kuzmin et al., 2016).
Formula (1) holds for inactivated inorganic solutions in equilibrium. This formula links the active acidity of the pH and the RP (Priluckij, 1997): where Ehminthe minimum theoretically expected value of the RP; рНactive acidity of the test solution.
Acquired RP values were compared with actual measurements of Ehact solution. Тhe change of the RP toward the recovery energy (RE) was determined by the formula (Priluckij, 1997): where REthe shift of RP to the side of recovered meanings (resilence); Ehminminimal theoretically expected meaning of RP; Ehactactual measured RP.

Mathematical and statistical methods
Pearson correlation coefficient measures the strength of the linear association between variables. Each variable should be continuous, random sample and approximately normally distributed. There are many rules of thumb on how to interpret a correlation coefficient, but all of them are domain specific. For example, here is correlation coefficient (Table 1) interpretation for behavioral sciences offered by Hinkle et al., 2003. The correlation coefficient can take a range of values from +1 to -1. Positive correlation coefficient means that if one variable gets bigger, the other variable also gets bigger, so they tend to move in the same direction. Negative correlation coefficient means that the variables tend to move in the opposite directions: If one variable increases, the other variable decreases, and vice-versa. When correlation coefficient is close to zero two variables have no linear relationship (Hinkle et al., 2003;Shendrik et al., 2019).

Sensory evaluation
The results of sensory evaluation (S.e., points) of the obtained infusions on the extractant are presented in the Table 2 and Figures 1.

Determination of Pearson's linear correlation
According to the physicochemical and sensory evaluation, mathematical and statistical analysis (Hinkle et al., 2003;Shendrik et al., 2019) was performed in the Pearson correlation matrix (Table 3). found that physicochemical parameters (t, pH, Ehmin, Ehact, RE) are statistically insignificant for sensory evaluation (S.e.), because the correlation coefficient is very weak (r 0.0-0.3) and weak (r 0.3-0.5). Also, a weak (r 0.3-0.5) and very weak (r 0.0-0.3) relationship is observed between temperature (t) and other physicochemical and sensory evaluation. The range of values with very high correlation (r 0.9-1.0) includes the following indicators: pH, Ehmin, Ehact, RE. Figure 6 shows the graphical dependence of pH on Ehmin. It was found that the pH is in the range of 5.  mV. According to the obtained equation, at a pH value of 6.00 Ehmin is 300 mV. When the pH value changes by 1 (pH 7.00), the Ehmin decreases by 60 mV (Ehmin 240 mV). That is, the relationship between Ehmin and pH is very high, because r=-1, because it is inversely correlated, which leads to an increase in pH to a decrease in the level of Ehmin.  Figures 7-11 show the graphical dependence of the pH level, Ehact, Ehmin, RE. It was found that Ehact is in the range from 93 to 180 mV, and the pH is 5.28-7.96. At the value of Ehact 111 mV, the pH level is 6.0. If you increase the pH to by one to 7.0 then the value of Ehact will be 145 mV, i.e. Ehact will increase by 34 mV. This is due to the fact that there is a very strong interdependence between the variables Ehact and pH (r=0.9). As the pH value increases, the Ehact index increases.
It was found that RE is in the range from 2.4 to 250.2 mV, and the pH is 5.28-7.96. When the value of RE 190 mV, the pH level is 6.0. If you increase the pH by one to 7.0, the value of RE will be 95 mV. Increasing the pH per unit from 6.0 to 7.0 leads to a decrease in RE by 94 mV. This is due to the fact that there is a very strong interdependence between the variables RE and pH (r=-1.0). As the pH value increases, the RE decreases.
The general graph of the three most correlation-significant physicochemical parameters is shown in Figure 12. In volumetric form, it is seen that some points (Ehact, RE, Ehmin) are as close as possible to the surface, i.e. there is a very strong correlation between them. The farther the points are from the surface, the weaker the relationship. Based on mathematical and statistical analysis, it was found that physicochemical parameters (pH, Ehmin, Ehact, RE) are statistically insignificant for sensory evaluation (S.e.) and infusion temperature (t). The range of values with very high correlation (r 0.9-1.0) includes the following indicators: pH, Ehmin, Ehact, RE.

Sensory evaluation of tea-herbal compositions with the addition of spicy-aromatic vegetable raw materials
The results of sensory evaluation of tea-herbal compositions are shown in table 4.  The highest score was obtained by tea-herbal compositions based on Melissa officinalis L. and a mixture of Melissa officinalis L.+Agastache foeniculum L. (1:1) -S.e. 4.975 points. The prospects of creating tea-herbal compositions based on ready-made dried mixtures have been confirmed by many authors (Alaşalvar, Çam, 2019;Tülek et al., 2020).

Sensory evaluation of white main sauce with the addition of spicy-aromatic vegetable raw materials
Evaluation of spicy-aromatic plants in mixtures showed that unsurpassed in taste, aroma and overall tasting evaluation of white main sauce based on meat broth with the addition of spicy spices (bay leaf, black peas, ground black pepper) and experimental samples of plants (broth) from beef + bay leaf + black pepper peas + ground black pepper + greens + Hyssopus officinalis L. + Ocimum basilicum L. + Dracocephalum moldavica L.) ( Table 5).
The undoubted advantage of non-traditional for restaurant spicy-aromatic vegetable raw materials is its biological value. The presence in the composition of substances that have antimicrobial, antioxidant, hepatoprotective properties, improve digestion when used daily in small doses. They do not cause allergies, have a positive effect on the psychophysical state of man. Studies have confirmed the value and availability of spicy-aromatic vegetable raw materials to culinary dishes and can be successfully used instead of the traditional set of spices or supplement them.

Sensory evaluation of red main sauce with the addition of spicy-aromatic vegetable raw materials
The addition of spicy-aromatic vegetable raw materials to the red main sauce significantly enriched it and increased the tasting score (Table 6).  For the production of red main sauce used a hybrid of tomatoes «Maximato F1», which have an increased dry matter content -5.2%; total sugar -3.0%; vitamin C content -20.9 mg/100 g; total acidity -0.51 %, which significantly exceeds other tomato hybrids.
To enrich the aroma and taste of the red main sauce, it is recommended to add spicyaromatic herbs, especially Ocimum basilicum L. S.e. -5,000 points.

Sensory evaluation of compotes with addition of spicy-aromatic vegetable raw materials
Traditionally, the healing drink in Ukraine is dried fruit compote. The aroma and taste of compotes were improved by adding spicy-aromatic vegetable raw materials (Table 7). The samples with the addition of spicy-aromatic herbs in aroma, color and taste were at the level of control (compote made from dried apples), slightly lower scores on aroma and taste can be considered insignificant compared to the fact that herbs significantly enriched the biochemical composition of the product. The specimen with the addition of Agastache foeniculum L. (S.e. -5,000 point), which was better than the control, was especially distinguished.

Conclusions
1. The expediency of using non-traditional for restaurant technology spicy-aromatic vegetable raw materials in the creation of tea-herbal compositions, sauces of white and red main, compotes, in order to increase the biological value and improve sensory characteristics. 2. Experimental studies show that all aqueous-alcoholic extracts of aromatic origin contain antioxidant systems. It was found that the recovery value of all the tested extracts is positive and ranges from (RE) 120.6 (Agastache foeniculum L.) to 250.2 mV (Hyssopus officinalis L.). 3. Based on mathematical and statistical analysis, it was found that the infusion temperature (t) has a statistically insignificant effect on physicochemical parameters (pH, Ehmin, Ehact, RE), which have a statistically insignificant effect on sensory evaluation (S.e.). The range of values with very high correlation (r=0.9-1.0) includes the following indicators: pH, Ehmin, Ehact, RE. 4. Improvement of restaurant technology by adding spicy-aromatic raw materials allows to increase the redox properties of the product, increases consumer properties and reduces the cost of the finished product. 5. Compositions of spicy-aromatic vegetable raw materials for restaurant technology in the production of tea-herbal compositions, white and red main sauces, compotes of high biological value and improved sensory characteristics have been studied.