Application of Honey from Hedera rhombea as a Sugar Substitute to Design Functional Cookies for Controlling Carbohydrate Digestion

Abstract

In this study, honey from Hedera rhombea was used as a sugar substitute in cookie-making to design functional cookies for controlling carbohydrate digestion. Honey from H. rhombea contained glucose (0.56±0.11 mg/mg), fructose (0.27±0.06 mg/mg), and phenolic compounds (46.61±0.05 mg gallic acid equivalents/100 g). When honey from H. rhombea was used as a sugar substitute in the cookie dough, it decreased the dough stability and increased the degree of softening from the farinograph compared with the control dough, which implies a weaker gluten network formation. Moreover, the honey influenced the baking performance by decreasing the spread ratio and hardness, resulting in the production of softer cookies with a dark yellow color. Finally, the cookies prepared with honey exhibited reduced amounts of reducing sugars against α-amylase because of the antioxidant activity of phenolic compounds within the honey, indicating slower carbohydrate digestion. These results provide insights into how to use honey as a sugar substitute to design functional foods for modulating the postprandial glycemic response.

INTRODUCTION

Obesity is a major health concern worldwide as it increases the risk of heart disease, diabetes, hypertension, and other diseases (Piché et al., 2020; Powell-Wiley et al., 2021). Although diet and physical activity are important in managing obesity, eating habits (e.g., food intake patterns including sugar consumption) play a critical role in weight gain (Yamakawa et al., 2020; Nguyen et al., 2023). Therefore, considerable attention has been directed toward controlling sugar intake for the treatment of obesity.

Among bakery products, cookies are prepared from soft or weak flour with high amounts of shortening and sugar. Sugar significantly contributes to the color and texture in cookie-making. However, the chronic consumption of cookies or even foods with high sugar content can lead to obesity and diabetes mainly because of excessive calorie intake (Stanhope, 2016; Micha et al., 2017). Thus, many individuals and food manufacturers have taken an interest in sugar substitutes to overcome health problems associated with sugar consumption.

Ivy honey has been used not only as a food sweetener but also as medicine as it exerts anti-inflammatory, antidiabetic, and antioxidant effects (Sen et al., 2023; Angioi et al., 2024). Hedera rhombea, commonly known as Japanese ivy, is an ivy species that originates from the coastal regions and certain islands of East Asia. It mainly contains caffeic acid, 3,5-dicaffeoylquinic acid, and rutin (Lee et al., 1993). In oriental medicine, H. rhombea is primarily used to treat hypertension and tumors (Lee et al., 1993; Kim and Kim, 2021). Although the benefits of honey from H. rhombea are relatively unknown, honey could be used as a functional sweetener with health benefits.

According to previous studies, honey from Trifolium alexandrinum decreased the postprandial glycemic index in patients with type 1 diabetes (Abdulrhman et al., 2013), and weight gain was significantly lower in honey-fed rats than in sucrose-fed rats, even with a comparable food intake (Chepulis, 2007). In another study, substituting sugar with spray-dried honey powder in cookie-making improved the chemical and nutritional characteristics of cookies (Kılınç and Demir, 2017). Moreover, in a study exploring honey as a sugar alternative in gluten-free bread production, five Sardinian honeys exhibited distinct rheological and textural properties, depending on their botanical origins (Cannas et al., 2024).

Therefore, in this study, we systematically explored the effects of honey from H. rhombea as a sugar substitute in cookie-making to evaluate the baking performance and control carbohydrate digestion. The findings from this study offer insights into how honey could be used as a sugar substitute to design functional bakery products that control the carbohydrate digestion rate for glycemic response modulation.

MATERIALS AND METHODS

Materials

H. rhombea honey was obtained from the Jeju Ivita Honey Research Institute. All ingredients for the cookie-making process (e.g., soft wheat flour, baking powder, nonfat dry milk, shortening, sugar, salt, and baking soda) were purchased from a local grocery store. α-Amylase from porcine pancreas (Product No: A3176) was purchased from Sigma-Aldrich.

Sugar composition of H. rhombea honey

The sugar composition of H. rhombea honey was profiled using a high-performance anion-exchange chromatography (HPAEC) system (Thermo Fisher Scientific) equipped with an electrochemical detector and a CarboPac PA1 column (4×250 mm, Thermo Fisher Scientific). After dissolving the honey in water, it was filtered through a 0.22 µm nylon syringe filter prior to injection into the HPAEC system. A mobile phase of 120 mM sodium hydroxide was used at a flow rate of 1.0 mL/min.

2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity

H. rhombea honey was mixed with a DPPH solution (0.2 mM) at room temperature for 30 min. Subsequently, the absorbance was measured at 517 nm using a microplate reader (Molecular Devices). The DPPH radical scavenging activity was calculated using the following equation:

$$\text{Radical scavenging activity (\%)=}\left[\text{1-}\left({\text{Abs}}_{\text{Sample}}{\text{-Abs}}_{\text{Blank}}\right)\right]\text{×100}$$

Total phenolic compounds

The total phenolic contents in H. rhombea honey were analyzed by using the Folin-Ciocalteu (FC) method. The honey sample (350 µL) was mixed with the FC solution (350 µL), and then 700 µL of sodium carbonate was added to the honey sample solution. Thereafter, the mixture was further incubated at room temperature for 1 h. The absorbance of the sample solution was recorded at 720 nm using a microplate reader. The total phenolic contents in the honey were expressed as gallic acid equivalents (GAE)/100 g.

Cookie preparation

Cookie samples were prepared following the method approved by the American Association of Cereal Chemists (Method 10-52; AACC International, 2000) with slight modifications. The cookie formulation is shown in Supplementary Table 1. Shortening was mixed with sugar or dried honey powder (10%, 20%, and 30% weight base), nonfat dry milk, and baking powder for 3 min at speed 1 using an 11a mixer (KitchenAid) equipped with a paddle beater to form a cream. Following the formation of a cream, salt, baking soda, and water were added to the cream mixture and then mixed for 3 min at speed 2. The mixture was continuously mixed with soft wheat flour for 25 min at speed 2 to produce a dough. Thereafter, the dough was divided into six portions. Each portion was cut into a cylindrical shape with a diameter and thickness of 6 and 1 cm, respectively, after 1 h of storage at 4°C. The dough was baked using a deck oven (Daehung Softmill) at 200°C for 10 min and then allowed to cool down at room temperature for 1 h.

Dough development analysis

The dough development of soft wheat flour with dried honey powder was analyzed using a farinograph (Anton Paar). Soft wheat flour with dried honey powder was loaded into the farinograph bowl and mixed with water to produce the dough. The dough was subjected to dual-mixing (120 rpm) during a programmed heating and cooling cycle where it was held at 30°C for 8 min, heated to 90°C at 4°C/min, maintained at 90°C for 7 min, cooled to 50°C for 4°C/min, and allowed to stand at 50°C for 10 min.

Geometry measurement

The diameter and height of the cookies were analyzed using the method approved by the AACC (Method 10-52; AACC International, 2000). Six cookies were placed next to each other and then rotated 90° for four times to measure the total diameter. Furthermore, the cookies were stacked twice in different orders to calculate the total height.

Color measurement

The color changes of the cookies made with dried honey powder were analyzed using a handheld color chromameter (Konica Minolta). The values of L* (lightness/darkness), a* (redness/greenness), and b* (yellowness/blueness) were recorded. The total color difference (DE) was calculated using the following equation:

$$\text{DE=}\sqrt{{\left(L{*}_{Control}-L{*}_{Sample}\right)}^2+{\left(a{*}_{Control}-a{*}_{Sample}\right)}^2+{\left(b{*}_{Control}-b{*}_{Sample}\right)}^2}$$

Textural property measurement

A puncture test was performed to measure the textural properties of the cookies using a texture analyzer (Food Technology) with a cylindrical probe equipped with a diameter of 0.5 cm and a 25 N load cell. The cookie samples were placed centrally on the platform of the texture analyzer. Then, the probe penetrated the cookies at a crosshead speed of 100 mm/min.

Digestibility measurement

The digestibility of the cookies made with honey was determined by measuring the released reducing sugar from cookies against α-amylase from porcine pancreas. The cookies were ground and passed through a 100-mesh sieve. The cookie powder was mixed with sodium phosphate buffer (pH 6.9, 100 mM) and prewarmed at 37°C for 10 min. The prewarmed solution was further mixed with α-amylase and then placed into a thermomixer at 37°C for 2 h. After incubation, the test solution was transferred into boiling water to terminate α-amylase activity. The amount of reducing sugars as digested products was determined using the dinitrosalicylic acid method (Potì et al., 2019).

Statistical analysis

All experiments were performed in triplicate, and data were expressed as the mean±standard error of the mean. Differences across treatments were analyzed by one-way analysis of variance, followed by Duncan’s multiple range test using SAS v9.4 software (SAS Institute). P-values lower than 0.05 were considered to indicate a significant difference.

RESULTS

Sugar composition

The sugar composition is a critical factor in determining the quality of honey, including crystallization, energy supply, and glycemic response (Doner, 1977; Samanta et al., 1985). Therefore, the sugar composition was analyzed by measuring the amounts of glucose and fructose. The sugar composition of H. rhombea honey is shown in Fig. 1. The honey primarily comprised glucose and fructose, and the amount of glucose (0.56±0.11 mg/mg dried honey powder) was higher than that of fructose (0.27±0.06 mg/mg dried honey powder). Furthermore, H. rhombea honey had a higher glucose content compared with acacia honey (0.23±0.05 mg/mg dried honey powder), which is one of the most common types of honey. By contrast, the fructose content of H. rhombea honey was lower than that of acacia honey (0.41±0.09 mg/mg dried honey powder). The glucose and fructose levels of honey are closely associated with honey crystallization because glucose is less soluble than fructose. Similarly, Kashmiri honey contains higher levels of glucose than fructose, resulting in faster crystallization compared with other types of honey (El Sohaimy et al., 2015).

Fig. 1.

Sugar composition of Hedera rhombea honey.

Total phenolic content and antioxidant activity

Phenolic compounds have numerous health benefits, including the prevention of chronic diseases such as heart disease, cancer, diabetes, and neurodegenerative diseases, mainly because of their antioxidant activity (Potì et al., 2019; Lim et al., 2022). Honey also contains phenolic compounds, including flavonoids and phenolic acids, which contribute to its antimicrobial, anticancer, and antidiabetic activities. Therefore, the total phenolic content and DPPH radical scavenging capacity of H. rhombea honey were measured to evaluate its antioxidant activity. As shown in Table 1, the total phenolic content and DPPH radical scavenging capacity of H. rhombea honey were 46.61±0.05 mg GAE/100 g and 31.97±0.17%, respectively. In the study of Pauliuc et al. (2020), six different honeys had total phenolic content ranging from 18.91 to 23.71 mg GAE/100 g. In another study, the total phenolic contents of sunflower honey and acacia honey were 40 and 2－39 mg GAE/100 g, respectively (Al et al., 2009). For the DPPH radical scavenging capacity, honeys from several geographical regions showed distinct DPPH radical scavenging capacities, ranging from 31.1% to 86.9% (Anklam, 1998). Moreover, honeys with different botanical origins had DPPH radical scavenging capacity ranging from 55.49% to 79.05% (Mureșan et al., 2022). Meanwhile, H. rhombea honey contained a relatively high total phenolic content but slightly low DPPH radical scavenging capacity compared to honeys with different botanical origins. Therefore, H. rhombea honey could be used as a functional ingredient because of its antioxidant activity.

Table 1.

Total phenolic content and DPPH values of Hedera rhombea honey

Sample	TPC (mg GAE/100 g)	DPPH (%)
Honey from Hedera rhombea	46.61±0.05	31.97±0.17

Values are presented as mean±standard error of mean.

DPPH, 2,2-diphenyl-1-picrylhydrazyl; TPC, total phenolic content; GAE, gallic acid equivalent.

Dough development

Sugar is an important ingredient in dough-making as it significantly influences the thermomechanical properties of the dough and the quality of cookies or even bakery products (Woodbury et al., 2023). The effects of H. rhombea honey as a sugar substitute on dough formation are shown in Fig. 2. The water absorption, which refers to the amount of water needed to achieve a specific dough consistency (500 BU), and development time, which refers to the time to reach the dough’s optimal development, of the dough made with H. rhombea honey remained unchanged compared with those of the control. With regard to dough stability, the application of honey at a 30% sugar substitution level in dough-making produced dough samples with decreased resistance to deformation during overmixing. Furthermore, the dough made with H. rhombea honey at a 30% sugar substitution level showed a significantly higher degree of softening, indicating a softer formation of the protein network. Similar findings with other honeys were observed by Tong et al. (2010) and Marinopoulou et al. (2023). The changes in dough formation when using H. rhombea honey are likely the result of the distinct water absorption capacities of sucrose and honey, thereby affecting the quality of the dough or even bakery products (Farahnaky and Hill, 2007; Mudgil et al., 2016).

Fig. 2.

Farinograph parameters (A, water absorption; B, development time; C, stability; D, degree of softening) of dough made with Hedera rhombea honey at 10%, 20%, and 30% sugar substitution levels. Different letters (a,b) on the bars indicate significant differences at the 5% level. Values are presented as mean±standard error of mean. H10, 10% sugar substitution; H20, 20% sugar substitution; H30, 30% sugar substitution.

Baking performance

As described above, the substitution of sugar with H. rhombea honey for cookie-making induced dough formation changes, which affected the cookie baking performance. Therefore, the baking performances of the cookies made with honey were explored by analyzing their geometry, color, and texture.

During the baking process, cookies initially expand in every direction and then collapse under their own weight, eventually causing them to spread out. The ability of cookies to spread is one of their important physical features. When H. rhombea honey was used as a sugar substitute in the cookie formulations, it affected the dimensions of the baked cookies. As shown in Fig. 3 and Table 2, the diameters of all cookie samples were not significantly different. However, cookies made with H. rhombea honey exhibited a significant increase in height as the substitution levels increased, resulting in a decreased spread ratio. Nutter et al. (2017) reported that the dried honey powder from Prosopis sp. attracted more water from the gluten protein and acted as an antioxidant to reduce disulfide cross-linking, consequently interrupting the formation of the gluten network. Furthermore, similar results were observed by Bornare and Khan (2015) and Kılınç and Demir (2017).

Fig. 3.

Visual appearance of cookies made with Hedera rhombea honey. H10, 10% sugar substitution; H20, 20% sugar substitution; H30, 30% sugar substitution.

Table 2.

Baking performance of cookies made with Hedera rhombea honey

Properties	Control	H10	H20	H30
Geometry
Diameter (cm)	7.66±0.10a	7.60±0.08a	7.63±0.10a	7.59±0.08a
Height (cm)	1.28±0.01d	1.33±0.01c	1.38±0.01b	1.41±0.01a
Spread ratio	5.98±0.08a	5.71±0.08b	5.53±0.07c	5.38±0.06d
Color
L*	64.78±2.29a	57.01±1.52b	57.15±1.29b	51.74±4.83c
a*	9.91±1.50c	13.12±0.63b	14.19±0.51b	16.18±1.24a
b*	27.42±0.36c	27.77±0.40c	30.84±0.48b	33.66±1.99a
DE1)	−	8.45±1.48b	9.42±1.25b	16.04±4.26a
Texture
Hardness (N)	8.71±0.54a	8.52±0.72a	8.64±0.39a	7.71±0.23b

¹⁾Total color difference.

Values are presented as mean±standard error of mean.

Values in the same row with different superscript lowercase letters (a-d) indicate significant differences (P<0.05).

L*, lightness; a*, redness; b*, yellowness; H10, 10% sugar substitution; H20, 20% sugar substitution; H30, 30% sugar substitution.

The color changes in the cookies are shown in Fig. 3 and Table 2. The L* value of the cookie surface significantly decreased with increasing substitution levels, indicating more darkness. The application of honey in cookie-making induced a significant increase in the a* value (red/green), implying a redder appearance on the cookie surface. Furthermore, the b* value (yellow/blue) significantly increased with higher substitution levels, indicating a more yellowish appearance compared with the control. Overall, the total color difference (DE) in the cookies significantly increased depending on the amount of H. rhombea honey. The change in color on the cookie surface is because of its original dark yellow color.

Table 2 shows the textural properties of the cookies using a puncture test, which measures the value of the breaking force as an indicator of hardness. The substitution of sugar with H. rhombea honey in cookie-making resulted in a decrease in the hardness of the cookies as the substitution level increased. Among all cookie samples, the cookie made with H. rhombea honey at a 30% sugar substitution level had the lowest hardness (7.71 N), whereas the control cookie had the highest hardness (8.71 N). This is likely the result of a higher degree of softening from the farinograph (Fig. 2), which induces the formation of a weaker gluten network compared with the control. Moreover, a previous study found that the addition of honey to the cookie formulation decreases the hardness of the samples (Bornare and Khan, 2015).

Digestion rate

The application of H. rhombea honey in cookie-making induced changes in the physicochemical properties of the cookies. This implies that the carbohydrate digestive enzymes (α-amylase from the salivary gland and pancreas and α-glucosidase in the small intestine) act differently on the cookie samples to produce glucose as a digestive product. Therefore, the in vitro digestion rate of the cookies samples was analyzed by measuring the amount of reducing sugar released in response to α-amylase from porcine pancreas, which plays an important role in controlling glycemic response (Lim et al., 2019).

The amount of reducing sugar released from the cookies during the 2-h digestion process by α-amylase is shown in Fig. 4. The substitution of sugar with H. rhombea honey in cookie-making decreased the amount of reducing sugar released from the cookies compared with the control cookie. Furthermore, the reduction in reducing sugar gradually increased with increasing substitution levels. Since H. rhombea honey contains phenolic compounds (mg GAE/100 g), mainly caffeic acid, 3,5-dicaffeoylquinic acid, and rutin (Lee et al., 1993), and exhibits DPPH radical scavenging capacity (Table 1), the reduced digestion rate may be due to the presence of antioxidant activity, which acts as a natural inhibitor against α-amylase.

Fig. 4.

Digestion rate of cookies by α-amylase at 37°C for 2 h. Different letters (a-d) on the graphs indicate significant differences at the 5% level. Values are presented as mean±standard error of mean. H10, 10% sugar substitution; H20, 20% sugar substitution; H30, 30% sugar substitution.

Discussion

In this study, the effects of H. rhombea honey as a sugar substitute in cookie-making were systematically investigated by measuring the sugar composition, total phenolic content, dough formation, baking performance (including geometry, color, and texture), and in vitro carbohydrate digestion. The application of honey as a sugar substitute in cookie-making induced changes in the dough formation properties, decreasing the stability and increasing the degree of softening. This is closely associated with the distinct hydration abilities of sucrose and honey, and the distinct hydration abilities cause different levels of intermolecular hydrogen bonds between sugar molecules (Evageliou et al., 2000; Tunnarut and Pongsawatmanit, 2017), resulting in the development of distinct gluten network structures. According to Nam et al. (2025), tannic acid or even phenolic compounds act as antioxidants that can cleave inter- and intramolecular disulfide (SS) bonds, resulting in structural changes in the gluten network. Therefore, the antioxidant activity of honey is expected to disrupt gluten network formation, leading to the formation of softer dough (Fig. 2). Consequently, the dough made with H. rhombea honey produced a softer cookie compared with the control cookie (Table 2). This is likely the result of distinct water retention properties between sucrose and glucose. H. rhombea honey contains a high amount of glucose, leading to the retention of more moisture and producing softer cookies (Manohar and Rao, 1999). The cookie made with H. rhombea honey exhibited reduced amount of reducing sugar against porcine pancreatic α-amylase, implying a slower carbohydrate digestion rate (Fig. 4). This is likely the result of the antioxidant activity from the phenolic compounds in honey, as shown in Table 1. H. rhombea contains caffeic acid, 3,5-dicaffeoylquinic acid, and rutin (Lee et al., 1993), and the phenolic compounds exhibited inhibitory properties against α-amylase or even enzyme proteins through noncovalent binding (Yu et al., 2021). The phenolic compounds in honey bind with enzyme proteins mainly through hydrogen bonds and subsequently inhibit their activity to digest substrates, resulting in a slower digestion rate (Lim et al., 2022). Although the application of H. rhombea honey as a sugar substitute in cookie-making induced a slower digestion rate compared with that of the control, additional research is needed to determine how different types of honey (e.g., acacia, clover, or manuka) affect the carbohydrate digestion rate since honeys from different origins have distinct phenolic compositions.

Excessive sugar consumption causes glucose spikes, which can lead to chronic diseases, including obesity, diabetes, heart disease, stroke, and some cancers (Hu and Malik, 2010). Thus, the application of H. rhombea honey as a sugar substitute has the potential to modulate the postprandial glycemic response by decreasing carbohydrate digestibility. Furthermore, the decreased carbohydrate digestibility might lead to the transfer of carbohydrates into the distal small intestine, where they interact with enteroendocrine L-cells, which secrete glucagon-like peptide-1 (Lim et al., 2021).

This study showed that the substitution of sugar with H. rhombea honey in cookie-making resulted in softer cookies with a dark yellowish color. These cookies exhibited slower carbohydrate digestion because of the antioxidant activity of the honey. Taken together, these findings suggest that H. rhombea honey could be used as a sugar substitute to develop functional foods that can control carbohydrate digestion for modulating the postprandial glycemic response.

SUPPLEMENTARY MATERIALS

Supplementary materials can be found via https://doi.org/10.3746/pnf.2025.30.4.391