Nutrition and food are important factors in maintaining health and well-being of the population. Adolescence is a period of growth and development with lasting impacts on lifelong health and future generations (Das et al., 2017). Proper nutrition during early years helps children to develop cognitive, motor and also socioemotional aspects which in turn will benefit the society as well (Mattei and Pietrobelli, 2019). Savarino et al., (2021) reported that the various physical changes that take place during adolescence raises the need for nutrition to support growth and development. Micronutrient deficiencies during this period can impose adolescents to a number of health concerns (Parajuli and Prangthip, 2025).
       
Adolescents and schoolchildren in developing nations consume a limited variety of foods, with little or no fruits and vegetables in the diet. Both the energy intake and the micronutrient intake are low (Ochola and Masibo, 2014). According to the Comprehensive National Nutrition Survey (CNNS) 2019, one-fourth of Indian children and adolescents were thin, with 5.0-6.5 per cent severely thin. Additionally, 3.7-4.8 per cent were overweight and between 1.1 per cent and 1.3 per cent were obese. A multicentric cross-sectional study in India assessed the association between blood levels and dietary intake of key minerals and vitamins in 2,428 urban schoolchildren (6-16 years). Data from 60 schools (April 2019-February 2020) showed high inadequacies in case of calcium (93.4%), iron (86.5%), Zinc (84.0%), selenium (30.2%), folate (73.8%), vitamin B12 (94.4%), vitamin A (96.0%) and vitamin D (100.0%) (Awasthi et al., 2023). Imbalanced and incomplete diets are the primary reasons of high prevalence of micronutrient deficiencies among adolescents. According to Del Campo  et al. (2024), picky eating and food neophobia are common among children, which are characterized by limited food variety and rejection of new foods, resulting in reduced consumption of essential nutrients like vitamin E, folate, fibre, vitamin C and iron.
       
Dietary diversity, nutrition education, supplementation and food fortification are considered to be efficient ways to address micronutrient deficiencies (Bechoff et al., 2023). Kaur et al., (2022) has discussed in one of his studies about a new “food-to-food fortification” strategy that has been proposed to increase bioavailability by employing nutrient rich food-based fortifiers to boost bioavailability and supply extra nutrients. Functional foods enhanced with bioactive substances such as carotenoids, antioxidants, essential fatty acids, vitamins, minerals and bioactive peptides greatly aid in promoting health and preventing micronutrient deficiencies (Lee, 2024). The phytochemical and functional properties of fruits and vegetables make them ideal for use as natural ingredients for the development of value-added functional foods rich in micronutrients and other bioactive compounds (Ciccoritti et al., 2024). Fortification of food products using vegetable-based ingredients has been reported to enhance micronutrient content while also contributing bioactive compounds and functional benefits (Sinha and Sharma, 2023). However, fruits and vegetables have a short shelf life, deteriorate quickly after harvest and lose quality over time. Therefore, fruit and vegetable industry aims to develop innovative products with high quality, safety and optimal nutrition to meet growing consumer demands (Tylewicz et al., 2019).
       
Meanwhile, the food industry is shifting towards developing products with reduced sucrose and artificial additives while enhancing antioxidant, protein and fibre content. As a result, traditional confectionary products are losing popularity, leading to a growing interest in functional confectionary products (Tarahi et al., 2024). Hence, to meet consumer demand for healthier confectionary products, functional candies made from fruits and vegetables can be an effective way to deliver micronutrients. The development of micronutrient rich jelly candies presents a distinctive opportunity to address nutritional gaps among adolescents and improve the nutritional profile of confectionary products; as well as reduce the post-harvest losses of fruits and vegetables.
       
Hence, the present study was conducted to i) formulate and standardise micronutrient rich jelly candies, ii) analyse nutritional composition, physical characteristics, physicochemical properties, sensory characteristics and shelf life of the developed jelly candies and iii) study the acceptability of the micronutrient rich jelly candies among adolescents.

Materials
 
Spinach (Spinacia oleracea), beetroot (Beta vulgaris) and orange (Citrus sinensis) were selected for the formulation of micronutrient-rich jelly candies based on their high micronutrient content and functional properties. Spinach and beetroot were selected for their iron and antioxidant content, while orange was included as a source of vitamin C to enhance iron bioavailability. Pumpkin seeds (Cucurbita pepo) were incorporated to enrich the product with essential minerals, particularly magnesium, potassium, zinc, iron and calcium.
       
All ingredients, along with other raw materials such as sugar, honey, jaggery and gelatin, were procured from local markets in Coimbatore. Procurement was carried out following standard quality assessment criteria, including freshness, absence of visible contamination and appropriate packaging to ensure consistency and safety of the developed product.
       
The present study was carried out at Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore, Tamil Nadu, India. The experimental work was conducted over a period of six months during the research period.
 
Production of the jelly candies
 
Fresh spinach leaves and beetroot were manually sorted to remove extraneous matter, thoroughly washed and blanched for 10 minutes. The blanched vegetables were cooled to room temperature and homogenized to obtain a uniform paste. Oranges were washed, manually peeled to remove the outer rind and the juice was extracted using a mechanical juicer. The extracted juice was filtered through a 50 µm mesh sieve to obtain a clear juice extract. Pumpkin seeds were cleaned to remove impurities, shade dried and pan-roasted for 3 minutes to enhance flavour and reduce moisture content, followed by chopping into fine flakes. The overall process flow for the preparation of jelly candies is presented in Fig 1.


 
Standardisation of the jelly candies
 
As part of the process of standardisation, five experimental trials were conducted to determine the most acceptable formulation of the product. Standardisation of value-added food products through repeated formulation trials has been reported as an effective approach to achieve optimum sensory quality and nutrient retention, as demonstrated in nutri-rich snack food formulations (Patel et al., 2019). In the fifth experimental trial, the desired characteristics of the jelly candies were attained with spinach, beetroot, orange, pumpkin seeds, sugar and gelatin (30:30:30:05:05:05). This formulation was taken for standardisation. The standardised jelly candies were prepared in three variations using different sweeteners comprising sugar, honey and jaggery, to assess the product’s acceptability when formulated with natural sweeteners. The developed variations of the jelly candies are given in Table 1.


 
Sensory evaluation
 
The developed variations of the jelly candies were taken for sensory evaluation. In the present study a score card using the hedonic ratings of nine-point scale was used to assess the appearance, colour, texture, flavour, taste and overall acceptability of the developed jelly candies. For each score, a description of the sensory qualities to be assessed was provided in order to ensure that the results are clear, consistent and meaningful. The sensory characteristics of the developed jelly candies were analysed by 25 randomly selected panel members.
 
Statistical analysis
 
Statistical analysis was performed using IBM SPSS Statistics (Version 21.0) and Microsoft Excel. Sensory evaluation data of the formulated jelly candies were expressed as mean ± standard deviation. Differences among samples with varying concentrations were analysed using one-way analysis of variance (ANOVA). Statistical significance was determined by comparing the calculated p-values with a predefined significance level of p<0.05.
 
Physical and physicochemical analysis
 
The most acceptable variation of the product, indicated by the highest mean sensory score, was selected for further analysis, including physical examination and physicochemical analysis.
 
Texture analysis
 
Texture profile analysis was performed by the use of a texture analyser. The jelly candy was put on the base plate of the texture analyser and compressed twice with a 3-second break using circular probes (TATX2 50 mm) traveling at a speed of 1 mm/second.
 
Moisture content
 
The sample was crushed (5 g) and then dried under specific conditions until its weight remained constant. The moisture content was calculated by subtracting the final dry weight of the sample from its initial weight.
 
Total soluble solids
 
The sample was dried under controlled conditions until a constant weight was achieved. The weight of the dried residue was then divided by the initial weight of the sample to calculate the percentage of total soluble solids.
 
pH
 
A digital pH/mV meter was used to determine the pH of the sample. This was done by dissolving 2.5 grams of the sample in 50 ml of distilled water. The dissolved sample was filtered and checked for its pH using the digital pH/mV meter that was calibrated with a buffer solution of pH 4.0 and 9.2.
 
Proximate analysis
 
Estimation of protein content
 
The protein content was determined from the organic Nitrogen content by Kjeldahl method.
 
Estimation of total fat
 
The sample was defatted using Soxhlet extraction with petroleum ether (boiling range 40-60°C) following standard procedures (AOAC 948.22, 2005). Post-extraction, the solvent was recovered and the defatted sample was dried, cooled in a desiccator and weighed for analysis.
 
Estimation of total carbohydrate
 
The total carbohydrate content (in grams) was determined by subtracting the values of the moisture, total ash, total fat, total protein from 100 (AOAC, 2005).
 
Mineral content
 
Test portions were dry ashed by gradually increasing the temperature to 450°C at a rate of approximately 50°C per hour. The resulting residue was then dissolved in nitric acid and the mineral content (iron, calcium, magnesium and zinc) was determined using ICP-OES (AOAC 999.19, 2005).
 
Shelf-life analysis
 
The developed jelly candies were stored in airtight PET (Polyethylene Terephthalate) containers and their sensory attributes were evaluated on days 0, 5, 10 and 15 to assess variations in sensory characteristics over the storage period. To analyse shelf life, a comparative study was conducted between samples stored with and without aluminium foil wrapping.
       
Microbial testing, specifically total plate count (TPC), was also performed on days 0, 5, 10 and 15, where samples were serially diluted tenfold using appropriate diluents. Aliquots (1 mL) from each dilution were aseptically plated in duplicate by the pour plate method using plate count agar (≈15 mL at 45°C) and incubated at 30°C for 72 h or 37°C for 24 h. Colonies (≤300 per plate) were counted and microbial load was calculated using the standard formula:

N = ΣC /(n₁ + 0.1n₂)d

 
       
With results expressed as Colony Forming Units (CFU) per gram of sample.

Sensory evaluation
 
The mean sensory scores and standard deviations of the jelly candy formulations are presented in Table 2. Sensory evaluation demonstrated perceptible differences among the developed variations, which were statistically examined using one-way analysis of variance (ANOVA), with the corresponding F- and p-values summarised in Table 2. The results indicated that the jaggery-based formulation (CCC) obtained the highest scores for texture, flavour, taste and overall acceptability. ANOVA revealed significant differences (p<0.05) among formulations for these attributes, whereas no significant differences were observed for appearance and colour (p>0.05), indicating comparable visual characteristics across samples. Post hoc analysis using Tukey’s HSD test confirmed the superiority of CCC over AAA and BBB in texture, flavour, taste and overall acceptability. The improved sensory performance of CCC is due to the use of jaggery and its favourable interaction with other ingredients, while BBB showed relatively better taste and flavour than AAA but remained inferior to CCC overall. Variations in texture among the formulations were primarily influenced by the type of sweetener used. Dey and Sheth (2023) reported that honey, owing to its high moisture content, reduces structural stability, resulting in softer and stickier jelly candies, whereas jaggery substitution has been reported to impart a firmer and chewier texture, as discussed by Ravi et al., (2021), which has enhanced the textural acceptability of the product.


 
Physical and physicochemical properties
 
The physical and physicochemical parameters of the developed jelly candies are presented in Table 3.


       
The developed jelly candies had an average weight of 15 grams per piece, with a square shape (3 x 3 x 1.5 cm). Moisture content was 37.3%, low enough to limit microbial growth under refrigeration. The texture analysis shows a moderate hardness of 6.32 N, meaning the jelly candies offers some resistance to bite without being overly tough. A springiness of 12% indicates a slight recovery of shape after compression. The gumminess, measured at 0.85 N, reflects the force needed to break the jelly down for swallowing, while a low chewiness of 0.10 N suggests ease of mastication. A cohesiveness value of 13.5% demonstrates a moderate internal bond, helping the jelly candy retain its structure during handling. With zero adhesiveness, the jelly candy is not sticky, enhancing the ease of eating. The addition of gelatin played a key role in the texture profile of the jelly candies. However, the springiness (12%) and cohesiveness (13.5%) were lower compared to formulations using a gelatin-agar agar blend (Lemos et al., 2021). Total soluble solids (TSS) were 47%, contributing to sweetness, gel stability and shelf life. The precent total soluble solids present in the jelly candies reduced the risk of sugar crystallization, which can occur above a TSS level of 65% (Adaora et al., 2022). The pH of 3.74, due to citrus fruit and lemon juice, indicates mild acidity, which supports microbial stability and extended shelf life. These parameters reflect both quality and functional suitability of the product.
 
Nutritional composition
 
The developed jelly candies were analysed for the its energy, protein, fat, carbohydrate, iron, calcium, magnesium and zinc content. The results are presented in Table 4. The nutrient contribution of the jelly candies per day (30 grams) was compared with the Recommended Dietary Allowances for adolescents across age groups.


       
The nutrient composition of the jelly candies indicates modest yet significant contributions to the RDA of both adolescent boys and girls across age groups. The relative contribution of the energy content of the jelly candies to their RDA is slightly higher in girls (up to 2.12%) than in boys (2%), which can be attributed to the lower energy requirements in females, particularly at younger ages. Protein contribution shows a similar trend, with girls aged 10-12 receiving 4% of their RDA, marginally higher than their male counterparts at the same age. However, the gap narrows in older adolescents, reflecting changing physiological demands during puberty.
       
Among the micronutrients analysed, magnesium demonstrated the most significant contribution to the Recommended Dietary Allowance (RDA), accounting for approximately 4-8% across age groups for both boys and girls. Iron and calcium showed consistent contributions for both boys and girls across age brackets. Zinc also provided a notable contribution to the RDA of adolescents, ranging from 3-6 per cent. While modest, these contributions suggest that fortified snacks can play a supportive role in addressing micronutrient deficiencies and combating hidden hunger among Indian adolescents. In contrast, according to a study conducted by Hess et al., (2017), commonly consumed junk foods such as cookies, potato chips and soft drinks offer minimal nutritional value. For instance, soft drinks and cakes scored 17.2 and 11.1, respectively, on the Nutrient-Rich Foods (NRF) Index, highlighting their poor nutrient density.
 
Shelf life analysis
 
The shelf life of the developed jelly candies was analysed for a duration of 15 days. The jelly candies were stored in air tight containers and the containers were further kept in the refrigerator for a period of 15 days. The organoleptic evaluation of the jelly candies wrapped with and without aluminium foil was also compared during the period of storage.
 
Effect of storage on microbial growth
 
The microbial analysis of the jelly candies is presented in Table 5.


       
The total plate count of the developed jelly candies remained same till day 10^th and only a small increase in the total plate count was observed on day 15^th. The total plate count of the developed jelly candies remained within the safe limits which is below 5 x 10⁴ cfu/g. This can be attributed to the low pH (3.74) of the jelly candies.
 
Effect of storage on sensory profile

Storage at 4°C showed that aluminium foil wrapping preserved the sensory qualities of jelly candies for 15 days, while unwrapped samples showed texture degradation by Day 10. This highlights aluminium foil’s effectiveness in maintaining the product quality as also reported by Ayun et al., (2023), who discussed that aluminium foil is commonly used as a coating, especially for packaging food which must be protected from gas, moisture, odours and light so that it can better maintain the durability of the packaged product.
 
Packaging and labelling of the jelly candies
 
Effective packaging safeguards food products from environmental factors like light, moisture and microbial contamination, while also preserving nutritional quality. In this study, jelly candies were wrapped in colourful aluminium foil and stored in Polyethylene Terephthalate (PET) containers, chosen for their strong barrier properties, durability and product visibility. The findings of the study reveal that wrapping the jelly candies with aluminium foil leads to retention of the original sensory characteristics for a longer period of time. A similar study by Aly and El-Gendy (2023), found that MTPP (a metallic barrier similar in function to aluminium foil) showed superior protection for jelly candies, maintaining colour, texture and overall sensory qualities during storage. The results can guide the selection of appropriate packaging materials and shelf life recommendations for the product.
       
A label was designed following FSSAI Labelling and Display Regulations (2020), featuring nutritional details, ingredients, net quantity, price, manufacturing and expiry dates, storage instructions, manufacturer information, QR code, FSSAI licence number, barcode and relevant logos. This ensured regulatory compliance and enhanced consumer information and appeal.
 
Product evaluation and acceptability among selected adolescents
 
A sensory evaluation was conducted among 50 adolescents to assess the acceptability of the most preferred variation (CCC) of the developed micronutrient rich jelly candies. Participants were trained to evaluate key sensory attributes, appearance, colour, texture, flavour, taste and overall acceptability, using a nine-point hedonic scale. The mean scores and standard deviations were used to calculate acceptability percentages. Colour received the highest rating (8.4±0.67), followed by appearance (8.2±0.67), reflecting strong visual appeal. Texture and overall acceptability both scored (8±0.78) and (8±0.52) respectively, indicating good consumer satisfaction. Flavour and taste received slightly lower, but still favourable, scores of (7.8±0.87) and (7.6±0.86) respectively. All attributes had acceptability percentages exceeding 84%, demonstrating overall positive results. Thus, according to the results of sensory evaluation, it can be inferred that the product was well perceived among them with visual appeal being the most liked aspect. Previous studies on functional fruit-herb beverages by Sahrawat and Chaturvedi (2023) have emphasized that nutritional enhancement should not compromise sensory attributes, as consumer acceptance plays a decisive role in product success.

The present study aimed at formulating and standardising micronutrient rich jelly candies that can present a promising approach for delivering nutrients to adolescents. Adolescents often lack essential nutrients in their diet due to poor eating habits. Providing these nutrients in a more appealing and palatable form could effectively address existing micronutrient deficiencies. A comprehensive analysis of the developed jelly candies validated its potential as a micronutrient rich product in the market of health conscious consumers. Furthermore, the high level of acceptability among adolescents supported its validation as an attractive and palatable product. Thus, the study establishes that micronutrient rich jelly candies are both an acceptable and effective vehicle for nutritional intervention in adolescents. These findings open new avenues for the food industry to develop and market these candies as a commercially viable, healthy snacking option tailored for adolescent nutrition. With rising demand for functional foods and increased health awareness among consumers, especially parents and adolescents, food industries have a huge consumer market for the production of healthier food options.

The authors acknowledge the support and facilities provided by the Department of Food Service Management and Dietetics, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore, Tamil Nadu, for carrying out the present study.
 
Disclaimers
 
The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.
 
Informed consent
 
The research was approved for its ethical clearance by the Institutional Human Ethics Committee (IHEC) of Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore for the conduct of the study (Approval No. AUW/IHEC/24-25/FSMD/XPD06). Informed consent was obtained from all subjects prior to their participation in the sensory evaluation of the product.

The authors do not have any conflict of interest regarding the publication of this article.