Elemental Composition of Japanese Matcha Powder and Infusions—Potential Role as a Functional Food in Metabolic Health

Abstract

Matcha tea (Camellia sinensis (L.) Kuntze) is a Japanese powdered green tea characterized by an exceptionally high content of health-promoting compounds. It is produced by shading the tea plants for 21 days prior to harvesting. It can be consumed both as an infusion and as a whole powder form. The present study aimed to analyze the micro- and macronutrient composition of matcha tea infusions (traditional and daily) brewed with water at different temperatures, as well as that of matcha powder. Samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OS). Two types of matcha infusions were analyzed: daily and traditional, prepared at 25 °C, 70 °C, 80 °C, and 90 °C in addition to matcha powders. The results demonstrated that both infusions and matcha powder are sources of the tested elements (potassium, phosphorus, magnesium, calcium, zinc) and may complement a healthy, balanced diet. The type of tea significantly affected elemental content, while brewing temperature did not significantly influence the mineral composition of infusions. Taken together, these results indicate that matcha represents a nutritionally relevant beverage whose mineral profile may contribute to dietary quality and support physiological functions related to metabolic health.

1. Introduction

Tea is the second most consumed beverage worldwide, exceeded only by water. Many cultures worldwide have appreciated its properties for centuries. One of the many types of tea is matcha, a Japanese powdered green tea (Camellia sinensis (L.) Kuntze). It differs from traditional green tea primarily in its cultivation methods. Matcha is shaded during cultivation with bamboo covers for approximately 21 days before harvesting [1]. This photoprotective practice limits direct sunlight exposure and induces physiological stress. This process has been shown to result in increased synthesis of bioactive compounds such as amino acids, chlorophyll, and theanine. A single cup of matcha contains an antioxidant capacity estimated to be equivalent to that of approximately ten cups of traditional green tea [1,2]. Matcha is considered the most aromatic green tea and the highest-quality product due to its elevated theanine and caffeine contents. The relative proportions of the bioactive components of matcha determine its ‘umami’ flavor [3]. Due to its powdered form, matcha is consumed as a whole suspension, unlike other types of teas, thus delivering the wealth of bioactive compounds present in the infusion to the body. Matcha is also consumed as an addition to cakes and desserts, and the possibilities for its use in cooking are endless [4,5]. Despite its centuries-old tradition in Asian countries, matcha has recently gained popularity around the world. It is appreciated for its sensory and health-promoting properties [2]. In 2016, the global matcha market was valued at USD 2.62 trillion and is expected to grow at a compound annual growth rate (CAGR) of 7.6% until 2025 [1]. Matcha is generally classified into two types—daily and traditional—based on harvest time. Traditional matcha is a superior-quality tea and is produced from leaves from the first and second harvests (spring and early summer—from April to July). In contrast, daily matcha is a blend of leaves from the second and third harvests (early and late summer—from June to the end of August). Compared with traditional matcha, daily matcha is characterized by a paler hue and a more subtle aroma. It is recommended for people who prefer a lighter green tea flavour and as an ingredient for matcha lattes, smoothies, baked goods, and ice cream [3,6,7,8].

Tea is a source of numerous bioactive compounds, including a wide range of micro- and macronutrients [9]. Each of these compounds plays a distinct role in maintaining normal physiological functions, making adequate daily intake essential for health [10]. Matcha tea is not only a source of bioactive phytochemicals but also provides valuable amounts of essential macro- and microelements, which may contribute to maintaining proper metabolic balance. Despite the growing popularity of matcha, there is a lack of comprehensive studies critically assessing its elemental composition in both powder and infusion forms, highlighting the need to evaluate how its consumption contributes to dietary intake of essential macro- and microelements.

The present study aimed to determine, for the first time, the elemental content of matcha tea (daily and traditional) in both infusions and powder forms and to assess the effect of the brewing water temperature on the mineral profile of the infusions.

Hypothesis

The type and dosage form (powder or infusion) of matcha tea affect the micro- and macroelement contents.

2. Materials and Methods

2.1. Plant Material

The studied material consisted of two types of high-quality organic Japanese powder: green tea matcha (Camellia sinensis L. Kuntze), which is made from the leaves of Tencha and originates from the Uji region of Japan in the Kyoto prefecture. Traditional matcha (TM) comes from the first and second harvests of the leaves (spring and early summer—from April to July), whereas daily matcha (DM) comes from the second and third harvests (early and late summer—from June to the end of August). TM and DM samples were produced using the same cultivation practices and processing technology, including shading, steaming, drying and stone grinding, with harvest timing being the main variable. The harvest timing was selected as the primary distinguishing factor because leaf maturity is a well-established determinant of bioactive compound content in Camellia sinensis. Both teas are certified by the Japanese certification body JONA (Japan Organic And Natural Foods Association) and by the Polish AgroBioTest certificate (this unit is specialized in the certification of organic agricultural products, in accordance with EU regulations).

2.2. Preparation of Infusion

A total of 1.75 g of a plant material sample was transferred to a conical flask, to which 100.0 mL of distilled water was added at a given temperature (25 °C, 70 °C, 80 °C, and 90 °C—most commonly used to prepare plant infusions). The flask with the infusion was closed and rotated at 180 rpm (Brunswick model EXCELLA E24, New Brunswick Scientific, Edison, NJ, USA) for 10 min. After brewing, the plant parts were separated from the infusion by filtration. The infusions were allowed to cool to room temperature before being analyzed. Each infusion was prepared and analyzed in triplicate [3].

2.3. Determining the Element Contents in Infusions

2.3.1. Sample Preparation

Mineralization of the daily and traditional matcha powder and infusions was performed via the MARS 5 CEM microwave digestion system (CEM Corporation, Matthews, NC, USA). A volume of 0.8 mL was used for each sample. The samples were transferred into clean polypropylene tubes, followed by the addition of 2 mL of 65% nitric acid into each vial. The vials were then left for 30 min under a clean hood to allow for a prereaction phase. Subsequently, 0.5 mL of unstabilized 30% hydrogen peroxide was added to each vial. Once all the reagents were added, the mixtures were transferred into specialized Teflon vessels and digested in the microwave system for 35 min at 180 °C (with a 15-min ramp-up and a 20-min hold at 180 °C) [11]. At the end of digestion, the samples were cooled to room temperature and moved into acid-cleaned 15 mL polypropylene tubes inside a clean hood. A further 5-fold dilution was performed prior to ICP-OES (iCAP 7400 ICP-OES, Thermo Fisher Scientific Inc., Waltham, MA, USA) measurement. A volume of 2 mL was taken from each digest. The samples were spiked with yttrium (Y) as an internal standard to provide a final concentration of 0.5 mg/L, 1 mL of 1% Triton (Triton X-100, Sigma, Kawasaki, Japan), and diluted to a final volume of 10 mL with 0.075% nitric acid. Blank samples were prepared by adding 500 µL of concentrated nitric acid to tubes without any sample and then diluting following the same procedure. Calibration standards were prepared with varying concentrations of elements via the same method used for blanks and test samples. All the solutions were prepared with deionized water [11].

2.3.2. Sample Determination

Sample analysis was performed via inductively coupled plasma-optical emission spectrometry (ICP-OES) [12,13]. ICP-OES, which is equipped with a concentric nebulizer and a cyclonic spray chamber, enables the simultaneous quantification of both macro- and micronutrients. The measurements were conducted in both radial and axial viewing modes. The wavelengths used in the analysis were as follows: Zn, 206.200 nm; Cr, 205.560 nm; Mn, 257.610 nm; Cu, 224.700 nm; and Fe, 259.940 nm. Method validation involved the use of NIST SRM 8414 reference material (National Institute of Standards and Technology. Reference Material 8414: Bovine Muscle Powder. National Institute of Standards and Technology: Gaithersburg, MD, USA), determination of the limit of detection (LOD), and recovery assessment of the internal standard (yttrium). Emission lines were selected empirically during preliminary trials to minimize spectral interference. This validation strategy is widely adopted in ICP-OES analyzes, particularly for plant-based matrices [13]. The recovery of Y was within 90–106%. The R² values for all standard curves ranged between 0.998 and 1.000 [12].

2.4. Statistical Analysis

Statistical analysis was conducted via MedCalc^® Statistical Software version 20.218 (MedCalc Software Ltd., Ostend, Belgium; https://www.medcalc.org; accessed on 28 February 2024) and Microsoft Excel 2017. The distributions of values for individual parameters were assessed via the Shapiro–Wilk test. As the distribution of continuous variables deviated from normal and the assumption of homogeneity of variance was not met, non-parametric tests were applied. Specifically, the Kruskal–Wallis test was employed to evaluate differences between the studied parameters. Spearman’s rank correlation test was used to determine relationships between the parameters. The results are presented as median values and interquartile ranges (IQR). Differences were considered statistically significant at p ≤ 0.05.

Graphical analyses were performed via the Python programming language (version 3.12) with the Matplotlib version 3.10.5 and Seaborn version 0.13.2 libraries. Boxplots were generated on the basis of median and interquartile range (IQR) values to illustrate the variability of the analyzed parameters among different tea types. The plots were customized to display statistically significant differences between groups, indicated by asterisks corresponding to significance levels (p < 0.05).

3. Results

The infusions of both daily matcha (DM) and traditional matcha (TM) showed the presence of all the elements tested: calcium (Ca), chrome (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), phosphorus (P), lead (Pb), strontium (Sr) and zinc (Zn). Several statistically significant differences were observed. Daily matcha infusions contained higher levels of calcium and sodium, whereas traditional matcha infusions were characterized by a higher potassium and nickel content. For the other elements, no statistically significant differences were detected between the tea types (Figure 1; Table S1, Supplementary Materials).

In the matcha infusions studied, both daily and traditional, no statistically significant differences were recorded between the contents of the elements studied in the infusions prepared with water at different temperatures (Figure 2 and Figure 3; Tables S2 and S3, Supplementary Materials).

The matcha powder of both the DM and TM contained all the elements tested, except nickel. None of the analyzed elements showed statistically significant differences between the two matcha types (Figure 4; Table S4, Supplementary Materials).

4. Discussion

Matcha tea can be consumed in two primary forms: as infusions or in powder form (as an addition, for example, to desserts, cakes, etc.). Consequently, not only matcha infusions but also the powder were analyzed in this study. Furthermore, infusions are frequently prepared with water at different temperatures. Therefore, the next step of the analysis was to compare the effects of water at different temperatures on the contents of the analyzed elements.

In the present study, matcha was confirmed as a source of micro- and macroelements: calcium (Ca), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), phosphorus (P), lead (Pb), strontium (Sr) and zinc (Zn). The general pattern of elemental concentrations in the daily matcha infusions examined was as follows: K > P > Mg > Ca > Na > Mn > Zn > Cu > Sr > Fe > Ni > Pb > Cr. In the traditional matcha infusions tested, the pattern was slightly divergent: K > P > Mg > Ca > Mn > Na > Zn > Cu > Fe > Sr > Ni > Pb > Cr. The analysis of matcha powder has yielded varied outcomes regarding the elemental composition. In daily matcha, the pattern is as follows: K > Ca > P > Mg > Mn > Na > Fe > Zn > Cu > Sr > Cr > Ni, whereas in traditional matcha, the scheme appears to deviate from previous schemes: K > P > Ca > Mg > Mn > Na > Fe > Zn > Cu > Sr > Cr > Ni.

Depending on their contents in the environment, elements can be divided into micronutrients (also called trace elements) and macronutrients. An alternative classification system is predicated on the physiological importance of the elements and is characterized by the distinction between essential, nonessential, and toxic elements. Macronutrients are present in relatively large quantities in the environment. They are responsible for numerous physiological functions and are essential for the proper functioning of the body. Like micronutrients, it is necessary to supply them with food, as the human body is unable to synthesize them. Macroelements include magnesium, potassium, phosphorus, calcium, and sodium [14].

Magnesium plays a crucial role as a cofactor in more than 300 enzyme reactions that take place within the human body. It is an essential element for the proper functioning of the body [15]. The recommended dietary allowance (RDA) of magnesium for adult men is 420 mg/day, and for women, it is 320 mg/day. A cup of matcha (100 mL), therefore, provides approximately 0.90% of the magnesium requirement for a male individual and 1.20% for a female individual. 1.75 g of powder covers just under 0.70% of the requirement for a man and just over 0.80% of the requirement for a woman [10]. The percentage of coverage for a given element was calculated on the basis of the average elemental content of the infusions and powders.

Calcium is an essential element in the composition of bones. Its functions include the regulation of cell motility, gene transcription, and muscle contraction. Calcium is also responsible for regulating numerous cellular biological processes [16]. The RDA value for both men and women is set at 1000 mg/day. Analysis of matcha infusion indicated that less than 0.30% of the element’s RDA was present in a 100 mL cup, whereas 1.75 g of matcha powder provided approximately 0.50% of the RDA [10].

Notably, an adequate amount of phosphorus is necessary for the proper absorption of calcium. Phosphorus homeostasis is crucial for human health. It is imperative for the optimal functioning of both skeletal and nonskeletal tissues, in addition to its role in energy production. The disturbance of homeostasis can be attributed to the excessive addition of phosphates to processed foods, which has been demonstrated to have pathogenic consequences [17]. The RDA value for phosphorus for both men and women is 700 mg/day. Therefore, a cup of matcha provides approximately 1.10% of the required amount, whereas a teaspoon of powder weighing 1.75 g covers less than 0.80% of the sample. The ratio of phosphorus to calcium should be 1:1 to ensure proper absorption of the elements and the resulting bone mineral density, among other things [18]. This ratio was shown to be correct in the matcha powder under study. The infusions presented slightly higher phosphorus contents, which may be due to increased phosphorus permeation into water compared with that of calcium.

Potassium is closely linked to the control of blood pressure in the human body. Increased potassium intake alongside decreased sodium intake has a positive effect on human blood pressure, whereas increased sodium intake is associated with a risk of cardiovascular disease [19,20]. For potassium, only the AI (adequate intake) value was determined. For both men and women, the value is 3500 mg/day. Therefore, a cup of matcha covers approximately 1.20% of this value, while a teaspoon of matcha powder weighing 1.75 g covers just over 0.50% [10]. On the other hand, the AI value for sodium is 1500 mg/day for an adult. This means that 100 mL of matcha infusion will cover just over 0.10% of the AI value for sodium, while a 1.75 g serving of matcha powder will cover 0.01% of this value, highlighting the advantages of matcha [10]. Thus, the concentrations of potassium and sodium are beneficial to the prevention of cardiovascular disease in humans.

Micronutrients are essential for the proper functioning of the human body, despite their presence in trace amounts [21]. As cells are incapable of synthesizing trace elements, it is imperative to supply them with food. An imbalance, whether deficiency or excess of these elements, can result in many dysfunctions and diseases. Therefore, ensuring adequate intake of these elements through dietary sources is crucial [21]. Among the elements studied, trace elements include manganese, zinc, copper, iron, nickel, chromium, lead and strontium, with lead being one of the heavy metals that are toxic to the body [22].

A trace metal that is essential for the functioning of the body is manganese. Adequate concentrations of manganese are responsible for the normal function of the nervous system. Manganese has the ability to cross both the blood-brain barrier and the blood-cerebrospinal fluid barrier [23]. For manganese, an RDA value was not specified, with only an AI level of 2.3 mg/day for men and 1.8 mg/day for women. A 100 mL cup of matcha provides just under 40% AI coverage for men and just under 50% for women. 1.75 g of powder provides approximately 35% AI coverage for men and just over 40% AI coverage for women [10].

The importance of zinc for human health has been recognized for decades. A deficiency in this element can cause immune dysfunction and reduce testosterone levels. Recently, cognitive impairment resulting from zinc deficiency has also been reported [24]. The RDA value for zinc for an adult male is 11 mg/day, whereas for a female, it is 8 mg/day. A 100 mL cup of matcha infusion covers this requirement in less than 0.7% of men and less than 1% of women, while a 1.75 g teaspoon of powder covers it in approximately 0.40% of men and just over 0.50% of women [10].

Copper is a cofactor involved in many oxidation-reduction reactions catalyzed by enzymes. These enzymes include cytochrome c oxidase, superoxide dismutase, and ceruloplasmin. Furthermore, copper has many other functions that remain unclear [25]. The RDA level of copper for an adult is 0.9 mg/day, meaning that a 100 mL cup provides approximately 2% of the daily requirement for this element, and a 1.75 g teaspoon of powder provides approximately 3% [10].

Iron is an essential element for the proper function of the body. It is responsible for oxygen transport, immunity, cell division and differentiation, and energy metabolism, among other processes [26,27]. There is an increasing prevalence of iron deficiency leading to anemia. Iron deficiency is one of the major risk factors for disability and mortality worldwide, so an adequate supply of iron from the diet is important [26,27]. The RDA of iron for an adult man is 10 mg/day, and for a woman, it is 18 mg/day. One 100 mL of matcha infusion would cover the iron requirement of approximately 0.10% for men and 0.07% for women, whereas a 1.75 g teaspoon of powder would cover the iron requirement of 1.2% for men and 0.66% for women [10].

The significance of nickel in the human body remains to be substantiated. While preliminary findings suggest a potential benefit to reproductive function and bone strength, these observations require further validation. However, it is acknowledged that nickel can potentially induce allergic reactions by modulating metabolic pathways that underpin inflammatory responses. This phenomenon is chiefly connected with its occurrence in jewelry and its potential to cause skin allergies. However, further research is necessary to achieve a comprehensive understanding of the molecular mechanisms underlying nickel’s actions. [28]. In the case of nickel, AI, RDA, and RI (reference intake) values were not established. The tolerable upper intake level (UI) for nickel has also not been determined, as it has not been shown to have harmful effects after the ingestion of higher amounts [10]. According to the European Food Safety Authority (EFSA), the tolerable daily intake (TDI) for nickel is 13 µg/kg body weight/day. The nickel concentrations observed in the studied matcha infusions correspond to approximately 0.9–1.1% of the TDI per 100 mL serving for an adult weighing 70 kg, indicating that consumption of matcha does not pose a risk of excessive dietary nickel exposure [29]. Although statistically significant, the observed difference in nickel content was minimal and is unlikely to have biological or nutritional relevance. A plausible explanation for the presence of nickel in infusions and its absence in powder is that nickel in the solid material is predominantly associated with mineral phases. It leads to stronger residual matrix effects after digestion and signal suppression during ICP-OES measurement. In contrast, nickel detected in the infusions represents a mobile, water-extractable fraction that is analytically more accessible and less affected by such interferences. However, a potential contribution of the water extraction step cannot be excluded; however, this effect appears to be element-specific, as no comparable discrepancies were observed for other analyzed elements. Therefore, the observed nickel content in matcha infusions should be interpreted with caution, as the potential contribution of the water matrix cannot be fully excluded and was not independently quantified in this study.

Chromium is a trace element essential for the normal metabolism of carbohydrates. An adequate amount of chromium in the diet results in a reduced need for insulin and an improved blood lipid profile. Many chromium-stimulated processes are insulin-dependent [30]. The reference intake value of chromium for an adult is 40 µg per day. This means that a 100 mL cup of matcha made with 1.75 g of matcha covers approximately 2.5% of the RI, and a 1.75 g teaspoon of matcha covers 0.50% of the RI [10]. Reference intake values are intended primarily for food labeling and consumer guidance, whereas recommended daily allowances reflect physiological nutrient requirements and therefore provide a more appropriate framework for nutritional assessment [31].

Lead is highly toxic to humans. It is a heavy metal, and lead poisoning is a real threat to public health, particularly in developing countries. The emphasis is particularly on its neurotoxic effects, but also on its toxic effects on the cardiovascular system and kidneys. Its action is to induce oxidative stress in the body, which results in the formation of free radicals [32]. The temperature of the water used to prepare the infusions did not affect the content of this element. According to Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006, the permissible concentration of lead in plant products ranges from 0.050 mg/kg to 0.9 mg/kg, depending on the type of product (vegetables, fruits, spices, etc.), which means that the tested products are safe in this respect [33].

Strontium is not an essential element for human life, nor are toxic symptoms due to strontium overdose reported in humans [34]. Therefore, no RDA, RI, or UI values for strontium have been established.

To date, only one study has focused on the analysis of elements in matcha; however, these analyses were carried out in other types of tea. In the present study, matcha infusions were analyzed for the first time, and a comparison was made between infusions prepared with water at different temperatures. The study by Kolackova et al. is the only study to date to analyze matcha powder. An analysis was conducted on the elemental composition of ten matcha teas from various countries [4]. The authors demonstrated the presence of a broad spectrum of macro- and microelements, including Na, Mg, P, K, Ca, Mn, Fe, Cu, Zn, Cr, Ni, Sr and Pb [4]. The general pattern of elemental content in their study was therefore as follows: K > P > Ca > Mg > Na > Fe > Zn > Mn > Cu > Ni > Sr > Cr > Pb. These relationships are different from those obtained for matcha powder in the present study, although it closely resembles the pattern observed in our infusions. A study by Kolackova et al. and the present study reported analogous findings regarding the sodium, magnesium, phosphorus, calcium, copper, zinc, and lead content [4]. The differences in element concentrations observed between our matcha powders and those reported by Kolacková et al. are likely attributable to variations in cultivars, harvest time, processing practices, and sample origin. Despite these discrepancies, the overall patterns of elemental distribution remain comparable, thereby supporting the generalizability of the observed trends. Podwik et al. investigated the concentrations of elements in samples of various tea types and reported copper concentrations in green teas ranged from 11.8 mg/kg to 26.6 mg/kg, which is consistent with the values obtained in the present study for matcha [35]. These values are analogous to those obtained in the present study, which means that the copper content of matcha tea is similar to that of traditional green tea. Slightly higher copper concentrations were observed in black and oolong teas, likely reflecting the influence of fermentation and processing conditions [35]. The remaining white, red, and yellow tea samples presented lower copper contents [35]. With regard to manganese, authors found substantially lower concentrations in green teas compared to those in the present study, whereas black teas exhibited values closer to those reported here. For the remaining teas tested (red, white, yellow, and oolong), the highest result was obtained for white tea [35]. The highest concentration of zinc was obtained by Podwaika et al. for red tea. Green and black teas showed a similar concentration of this element obtained in the present study. Overall, these comparisons indicate that matcha shares a mineral profile comparable to that of traditional green tea, while differences relative to other tea types may be attributed primarily to processing and technological factors [35]. Malik et al. conducted a comprehensive analysis of both green tea infusions and leaves, reporting distinct elemental hierarchies for each matrix. The general pattern of elemental content in the green tea infusions was as follows: K > P > Mg > Mn > Ca > Zn > Ni > Cu > Fe, while in leaves it shifted to: K > Ca > P > Mg > Mn > Fe > Cu > Zn > Ni [9]. These patterns differ from those obtained in the present study for matcha powder and infusions. Compared with our results, Malik et al. reported lower concentrations of calcium, magnesium, phosphorus, and zinc in the green tea infusions. The remaining elements occurred at comparable levels [9]. These disparities may be attributable to the powdered form of matcha, which forms a suspension during the infusion preparation process, facilitating a greater transfer of mineral components into the beverage. In tea leaves, Malik et al. observed generally higher elemental concentrations than in our matcha powder, particularly for iron, potassium, and phosphorus, while the concentrations of manganese, zinc, and nickel were found to be lower. Nevertheless, matcha has the advantage of being ingested as a whole suspension, thereby ensuring the delivery of elevated quantities of the elements to the body [9].

Despite the evaluation of a range of brewing temperatures, no statistically significant differences in elemental content were observed in matcha infusions. The physicochemical processes that govern the transfer of elements from plant material to water are complex and depend on multiple interacting factors. These include the chemical binding of elements within the tea matrix, their water solubility, and diffusion dynamics. Research conducted on green tea infusions has demonstrated that the degree to which elements are extracted into the beverage can be influenced by several factors. These include temperature, water composition, pH, and brewing time. In addition, the binding of trace elements with organic constituents such as polyphenols and other ligands in the leaf matrix can also have a significant impact. These complexes can be either soluble or insoluble, and their behavior can affect leaching [36]. In various types of tea, an increase in temperature has been observed to result in an enhancement of the kinetic energy of water molecules and an acceleration of diffusion. However, the efficacy of extraction of a particular element is determined by its distinct thermodynamic and binding characteristics in relation to other constituents present within the matrix [37]. In the case of matcha, where finely ground leaves are suspended rather than brewed as whole leaves, the surface area in contact with water is already maximized. This may lead to rapid equilibration of most extractable elements across the entire temperature range studied. This, in turn, may reduce the observable effect of temperature alone on element concentrations. This mechanistic context suggests that the effect of temperature on element extraction may be less pronounced for matcha compared to whole leaf teas. It also highlights the need for future studies to investigate matrix binding and solubility phenomena (e.g., specification, complexation) to fully elucidate the physicochemical factors influencing the release of minerals and trace elements into the infusion.

The mineral composition of matcha, particularly its content of magnesium, zinc, and calcium, highlights its potential contribution to metabolic regulation and cardiovascular protection. These findings support previous research emphasizing the role of green tea components in improving insulin sensitivity and reducing oxidative stress. The distinctive consumption form of matcha means that the elemental composition of both powders and infusions may differ from that of conventional teas. This highlights the need for targeted analyses to better understand dietary exposure and potential nutritional contributions. The present study is distinguished by a robust methodology, employing appropriate tools to address the research questions. However, it is recommended that this study be conducted on a larger sample of subjects to achieve more comprehensive results.

5. Limitations

This study analyzed only two matcha products (daily and traditional) originating from a single geographical region. As mineral composition may vary depending on cultivar, agroclimatic conditions, harvest season, processing methods, and commercial batch variability, the results should not be considered representative of all Japanese matcha products. Therefore, conclusions regarding “Japanese matcha powder and infusions” should be interpreted with caution and limited to the analyzed samples. Additionally, the study assessed elemental composition only and did not evaluate mineral bioavailability or physiological effects, which may further limit extrapolation of the findings beyond the analytical context.

6. Conclusions

Matcha tea can supplement the daily diet, as it provides, in both infusions and powder, sizable amounts of elements essential for the body’s proper functioning. The temperature of the water used to prepare the infusions has been shown to have no significant effect on the content of the tested elements in matcha infusions, meaning that it can be safely prepared according to individual consumer preferences. Furthermore, dried matcha has been shown to be a better source of some elements than infusions (calcium, chromium, copper, and iron). It has also been shown that both infusions and matcha powder are not significant sources of heavy elements, meaning that they can also be safely consumed from this angle. Matcha tea provides meaningful amounts of essential elements that can support metabolic functions. Therefore, these findings have practical implications for consumers and the food industry, indicating that matcha can be prepared at a range of temperatures without loss of essential minerals and that both infusions and powders can meaningfully contribute to dietary intake of micro- and macroelements.