Formulation And Characterization Of A Plant-Based Paneer Analogue Using Underutilized Melon Seeds

In developing nations like India, where under nutrition and micronutrient deficiencies continue despite advancements in food production, malnutrition remains a significant global public health concern. Protein-energy malnutrition (PEM) is still prevalent among vulnerable populations, including women, children, and economically disadvantaged groups, mostly due to inadequate ingestion of high-quality protein sources (1). Despite being regarded as complete proteins, animal-based proteins like milk and dairy products are not widely used due to their expensive cost, limited availability, and issues including lactose intolerance and allergies (2). This necessitates looking into affordable, eco-friendly, and nutritionally adequate protein alternatives.
Due to growing health consciousness, environmental sustainability, and ethical considerations, plant-based diets have gained popularity in recent years. Plant proteins from legumes, grains, nuts, and seeds have gained popularity due to their nutritional worth and practical attributes (3).

Melon seeds are edible seeds from a range of cucurbit fruits that belong to the Cucurbitaceae family, such as watermelon (Citrullus lanatus) and muskmelon (Cucumis melo).

These seeds are recognized as important sources of nutrients and useful dietary ingredients, despite the fact that they are frequently thrown away as byproducts during fruit preparation. Melon seeds are extremely nutritious as they often contain 20–35% protein, 25–50% good fats, dietary fiber, and important minerals like calcium, magnesium, phosphorus, potassium, iron, and zinc. (4,5,6)

Melon seeds contain a variety of protein fractions, such as albumins, globulins, glutelins, and prolamins, which contribute to desirable functional properties like the ability to hold water, bind oil, emulsify, foam, and form gels (6, 7). With regard to these functional qualities, melon seed proteins can be added to a variety of food products, such as beverages, protein supplements, dairy and plant-based dairy substitutes, baked goods, and other functional food formulations. (4,5)

Melon seeds are high in bioactive compounds, such as phenolic compounds, flavonoids, tocopherols, phytosterols, carotenoids, and natural antioxidants, in addition to their macronutrient composition. These compounds have been linked to a number of health-promoting effects, such as immune-supportive, anti-inflammatory, antimicrobial, cardioprotective, and antidiabetic properties (8,4,5). Considering their outstanding nutritional profile and functional qualities, melon seeds have attracted growing interest as sustainable ingredients for the development of nutrient-dense and value-added foods.

Paneer is a classic dairy product from India that has several culinary applications and a high protein content. For vegetarians, it provides a significant source of protein. However, the rising price of milk and dairy products has made paneer somewhat pricey, making it unavailable to low-income populations. Additionally, as lactose intolerance is becoming more common and vegan diets are becoming more popular, there is an increasing need for plant based alternatives to conventional dairy products (9).

The creation of plant-based paneer substitutes has drawn interest as a possible remedy for these problems. The use of soy, almond, and groundnut as basis materials for paneer alternatives has been studied in the past; however, these substitutes occasionally have drawbacks such allergenicity, strong flavours, or greater manufacturing costs (2). In this regard, watermelon seeds offer an innovative and affordable substitute that hasn't been thoroughly studied. Watermelon seed-based paneer is made by first turning the seeds into plant milk, which is then coagulated to create a product that resembles paneer. This strategy makes greater use of underutilised resources and encourages the production of sustainable and functional foods.

Sensory evaluation plays a major role in the adoption of newly manufactured food products. Taste, texture, colour, fragrance, and general acceptability must all be assessed using accepted methods to ensure consumer preference. Additionally, nutritional profiling, including proximate composition analysis, is essential to assess the product's value as a food high in protein (10).

MATERIALS AND METHODS

Ripe melon fruits were used to gather melon seeds, and standard sources provided drinking water and food-grade coagulants such vinegar or lemon juice. To make melon seed milk, the seeds were cleaned, dried, dehulled, and gently roasted before being ground into a fine paste with water, mixed into a slurry, and filtered through a cotton cloth. After that, the extracted milk was standardised by varying the water content to achieve the proper consistency and total solids required for paneer. To induce coagulation, the standardised melon seed milk was heated to 70–80°C while being continuously stirred.

A muslin cloth was used to separate the ensuing curd from the whey, and any remaining moisture was forced out of the curd to form a compact paneer block. Before being examined further, the paneer was refrigerated at 4°C, allowed to solidify, and then cut into uniform cubes.

Figure 1: Flow design of the proximate analysis and antimicrobial activity of the melons paneer

Proximate Parameters	Watermelon Seed Paneer	Muskmelon Seed Paneer
Moisture (%)	3.98	3.64
Ash (%)	1.1	1.9
Energy (Kcal/100g)	205.8	210.4
Protein (%)	22.22	28.22
Carbohydrate (%)	17.3	18.4
Fat (%)	32.80	30.6
Crude Fibre (%)	58.4	57.2

Table 1: Proximate composition of melons paneer

Figure 2: Proximate composition of watermelon seed panner

Figure 3: Proximate composition of muskmelon seed paneer

Panellist	Watermelon Seed Paneer (Mean Score)	Muskmelon Seed Paneer (Mean Score)
Appearance	8.4	8.2
Colour	8.2	8.5
Aroma	7.6	8
Texture	8.5	8.2
Taste	8.5	8.5
Overall acceptance	8.4	8.5

Table 4: Sensory evaluation of melons paneer

Figure 4: Sensory comparison of melons paneer

Throughout the 10-day refrigerated storage period, the appearance of both types of paneer formulation remained consistent, demonstrating acceptable visual stability. The texture remained soft until the 10th day. The odor was devoid of off-odors for the first 5 days, but it got slightly unpleasant by the 10th day. Importantly, the existence of a rancid odor was not discovered until the 10th day, indicating that spoiling had begun at this point.

CONCLUSION

The current study showed that both the seeds can be successfully used to make plant-based paneer with adequate nutritional, functional, and sensory attributes. Muskmelon seed paneer had higher protein, phosphorus, potassium, and overall acceptability than watermelon seed paneer, which had greater fat content, crude fiber, calcium, magnesium, and zinc. Both formulations demonstrated antibacterial effectiveness against common foodborne pathogens and were well received by the sensory panellists. In addition to, the paneer remained stable under refrigerated storage up to 10 days with little changes in odour. Altogether, the findings emphasize the potential of melon seed paneer as a sustainable, nutrient-dense, and functional alternative to traditional dairy products, along with encouraging the value-added use of underutilized melon seed by-products in the development of novel plant-based meals.

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