India stands as the global leader in milk production, with an annual output of approximately 239.3 million tonnes during 2023-24, reflecting an annual growth rate of 6.2% (NDBB, 2023-24). The country’s livestock sector is vast and diverse, comprising 302.3 million bovines, 74.3 million sheep and 148.9 million goats. Within the bovine population, cattle represent a significant segment, contributing substantially to the nation’s dairy supply. Notably, cow milk production in India amounts to approximately 110.88 million tonnes, accounting for nearly 45.6% of total milk production (DAHD, 2023-24). Cow’s milk, a highly nutritious natural secretion, serves as a staple food worldwide, catering to the dietary needs of all age groups. It is a rich source of macronutrients such as proteins and lipids, along with essential micronutrients, including calcium, vitamins and trace minerals. Additionally, it contains an array of bioactive constituents such as immunoglobulin’s, peptides, enzymes, polyamines, hormones and growth factors, making it a complex colloidal system with high biological value (Haug et al., 2007). Recent studies published in ARCC journals have highlighted the growing application of fruit processing by-products and plant-derived bioactive compounds in functional dairy products due to their antioxidant potential and health-promoting properties. Incorporation of natural functional ingredients into fermented dairy products has been reported to improve nutritional quality while supporting sustainable utilization of agro-industrial waste. Several researchers in the Asian Journal of Dairy and Food Research also reported successful incorporation of natural plant materials and fruit residues into traditional dairy products with acceptable sensory and physicochemical characteristics (Suryawanshi et al., 2022; Hole et al., 2017). Traditional Indian dairy products play a vital role in preserving the nutritional essence of milk while enhancing its palatability and shelf life. Among these, shrikhand holds a prominent place, especially in western Indian states such as Maharashtra, Gujarat and Karnataka. It is a semi-solid, fermented dairy dessert prepared by blending chakka (Strained dahi) with sugar and various flavoring agents. The product is characterized by its smooth texture, mildly acidic-sweet flavor and nutritional richness. Shrikhand is particularly valued for its high protein content, phospholipids and beneficial microbial flora developed during fermentation, which contributes to its digestibility and shelf stability. With increasing urbanization and the expansion of dairy industries, shrikhand has found its place in organized markets and is now available in a wide range of flavors such as mango, kesar, elaichi and strawberry. Furthermore, its preparation method rooted in lactic acid fermentation presents a viable platform for incorporating functional ingredients with added health benefits. In recent years, there has been a growing consumer demand for functional foods, those that deliver health-promoting effects beyond basic nutrition. This trend has encouraged researchers and food technologists to explore plant-derived bioactive compounds as natural fortifying agents in dairy systems. Among such ingredients, pomegranate peel powder (PPP) has gained attention for its high concentration of antioxidants, phenolic compounds, flavonoids and ellagitannins. Though traditionally discarded as agro-waste, pomegranate peel has been scientifically recognized for its antioxidant, antimicrobial, anti-inflammatory and antidiabetic properties (Li et al., 2006; Tezcan et al., 2009). Its incorporation into food matrices such as yoghurts, beverages, ice creams and bakery products has demonstrated improvement in both nutritional and functional attributes. However, due to its high Polyphenolic load and distinct astringency, PPP can also influence the sensory, textural and visual properties of food products, especially those with delicate organoleptic profiles like shrikhand. Therefore, the development of PPP-enriched functional shrikhand requires careful optimization to ensure that the health-enhancing benefits do not compromise consumer acceptability. The present study was undertaken to formulate a functional shrikhand fortified with pomegranate peel powder (PPP) and to evaluate its sensory quality and colour parameters. This research was expected to contribute towards the formulation of value-added dairy products by integrating underutilized plant bioactives into traditional dairy matrices, thereby aligning with the broader goals of health-oriented food innovation and sustainable waste valorization.

The experiment was conducted at the Department of Animal Husbandry and Dairy Science, College of Agriculture, Vasantrao Naik Marathwada Krishi Vidyapeeth (VNMKV), Parbhani, Maharashtra, India. The whole, fresh cow milk used in the study was obtained from the Cattle Cross Breeding Project, VNMKV, Parbhani. The direct vat set (DVS) freeze-dried culture was procured from AB source biologicals, Pune, India. Refined crystalline sugar was purchased from the local market in Parbhani. For preparation of pomegranate peel powder, mature, dense and fresh pomegranate fruits of the ‘Bhagawa’ variety were sourced from the local fruit market. The edible pomegranate peel powder (PPP) was prepared in the laboratory by separating the peels from the fresh fruits, followed by blanching, cabinet drying and grinding into a fine powder. All the chemicals and reagents used in the experimental procedures were of analytical grade and obtained from standard suppliers available through the departmental laboratory.
 
Treatments
 
T₁- 100 parts of chakka.
T₂- 99 parts of chakka + 1 part of PPP.
T₃- 98 parts of chakka + 2 part of PPP.
T₄- 97 parts of chakka + 3 part of PPP.
T₅- 96 parts of chakka + 4 part of PPP.
       
In above all treatments sugar was added @ 40 per cent by weight of chakka.
 
Preparation of shrikhand
 
A process of shrikhand manufacture has been standardized. Fresh cow milk was procured and subjected for filtration. The milk was then cooled to 28-30°C, the optimal temperature for starter culture activity. A standardized mesophilic freeze dried lactic culture was inoculated at the rate of 1% DVS Culture, freeze-dried mesophilic lactic starter culture (AB source biologicals, Pune) and the milk was incubated at 37°C for 10 hours to allow fermentation, resulting in the formation of dahi. The curd (dahi) was transferred to a muslin cloth and suspended to drain the whey for 9 hours, yielding chakka, the semi-solid base for shrikhand. To the obtained chakka, powdered sugar was added at 40% of the chakka’s weight and thoroughly mixed to ensure uniform sweetness. At this stage, a pomegranate peels powder (PPP), prepared as described earlier and was incorporated at the predetermined optimized concentration. The mixture was then subjected to kneading, carried out on a clean stainless-steel surface to to achieve a smooth and homogenous consistency. The material was applied to prevent fat loss and maintain proper texture. Kneading was continued until a soft, cohesive and uniform mass achieved, resulting in the development of uniform functional shrikhand. The final product was packed in sterile polystyrene cups and stored under refrigeration conditions until further sensory and colour evaluations were carried out.
 
Methods
 
Sensory evaluation
 
Sensory evaluation of shrikhand was conducted using the 9-point hedonic scale described by Gupta (1976), where 1 indicates dislike extremely and 9 indicate like extremely. A panel of 10 semi-trained judges from the College of Agriculture and College of Food Technology, VNMKV, Parbhani evaluated the samples for flavour, mouthfeel, body and texture, colour and appearance and overall acceptability. The samples were served at chilled temperature (4±1°C) in coded containers under controlled lighting. Panelists were instructed to rinse their mouths with water between samples. Each treatment was evaluated in four replications and scores were statistically analyzed.

Instrumental colour analysis
 
Colour attributes were measured using a Hunter Lab Color Flex spectrophotometer (Color Flex EZ, Hunter Associates Laboratory Inc., USA). The instrument was calibrated with black, white and green standard tiles prior to analysis. Shrikhand samples were filled in clean, flat-bottomed containers and placed directly under the sensor. Colour was recorded in the CIE Lab* colour space, where L* indicates lightness (0 = Black, 100 = White), a* represents red-green spectrum (Positive = Red, Negative = Green) and b* denotes yellow-blue spectrum (Positive = Yellow, Negative = Blue). Three readings per sample were taken and average values were calculated for each treatment.
 
Statistical analysis
 
The data obtained in the study on various parameters were statistically analyzed by completely randomized block design (CRD). There was five treatments and each treatments had n=4 replications.

Several preliminary trails were conducted to standardize the processing technology of pomegranate peel powder based cow milk shrikhand on the basis of literature and preliminary trials.
 
Sensory evaluation of Shrikhand fortified with pomegranate peel powder
 
Sensory evaluation is critical in determining consumer acceptability of functional dairy products. The sensory attributes of shrikhand samples enriched with varying levels of pomegranate peel powder (PPP) from 0 part (T₁) to 4 part (T₅), were assessed using a 9-point hedonic scale. Attributes included flavour, mouthfeel, colour and appearance, body and texture and overall acceptability. The sensory evaluation trends observed across treatments are presented in Fig 1.


 
Flavour and mouthfeel
 
As shown in Table 1, flavour scores for T₁ and T₂ were the highest (9.00±0.004), with no significant difference (p>0.05), indicating optimal flavour retention upto 1 part PPP inclusion. A significant decrease in flavour score was observed from T₃ (8.00±0.004) to T₅ (6.00±0.004), likely due to the astringent, bitter taste of tannins and polyphenols present in PPP. A similar pattern was noted for mouthfeel, which declined from 9.00±0.003 in T₁ and T₂ to 6.00±0.003 in T₅. The fibrous texture at higher PPP levels possibly contributed to reduced creaminess and smoothness. These findings align with Suvera (2017) and Ahmed et al. (2022), who reported flavour deterioration in yogurt with increasing plant fiber additions and apple pomace and pomegranate peel powders addition. Also El-Said et al. (2014), who revealed that increasing the percentage of the added pomegranate peel extracts resulted in decrease in the sensory score of the stirred yoghurt, there by affected the sweetness.


 
Colour and appearance
 
The colour and appearance score of shrikhand followed a downward trend with increasing PPP. T₁ received the highest score (9.00±0.005), followed by T₂ (8.50±0.005), while T5 scored the lowest (5.50±0.005). The dark reddish-brown hue of PPP, attributable to anthocyanins and condensed tannins, altered the visual appeal of shrikhand. These findings are supported by Pugazhenthi et al., (2020), who observed similar declines in visual scores for citrus peel-fortified dairy products and Ahmed et al., (2022), who reported colour and appearance deterioration in yogurt with increasing apple pomace and pomegranate peel powders addition.
 
Body and texture
 
Body and texture score of shrikhand remained superior in T₁ and T₂ (9.00±0.005), followed by a significant decline in T₃ (8.50±0.005) and T₅ (6.50±0.005). The fibrous particles of PPP likely disrupted the protein matrix, resulting in lower cohesiveness. This observation supports the conclusions of Ahmed et al., (2022), who reported that body and texture score of yoghurt tended to decrease with the increase in apple pomace and pomegranate peel powders concentrations also Singh and Immanuel (2014) who reported that paneer prepared by the addition of natural antioxidant extracts of pomegranate, orange and lemon peels were acceptable at 2% level of inclusion. The results were also in close resemblance with the findings of El-Said et al. (2014), who revealed that increasing the percentage of the added pomegranate peel extracts resulted in decrease in the sensory score of the stirred yoghurt.
 
Overall acceptability
 
Overall acceptability of shrikhand was highest in T₁ (9.00±0.0047) and T₂ (8.87±0.0047), indicating that PPP can be included without compromising palatability. The lowest score (5.87±0.0047) was recorded for T₅. This observation supports the conclusions of Thorat (2018) and Abirami (2023), who found that higher levels of fiber-rich plant additives negatively impacted textural and sensory properties of shrikhand and related dairy products. Ahmed et al., (2022) found that Overall acceptability scores of functional yoghurt prepared by using freeze-drying on apple pomace and pomegranate peel powders were found to be significantly higher than other analyzed treatments. El-Shafei et al. (2017) evaluated the possibility of utilization of pomegranate peel extract as natural preservative in goat’s cream cheese, Organoleptic results of these study showed that concentration of Pomegranate peels extract up to 0.5% and 1.0% respectively recorded high scores. Suryawanshi et al., (2022) reported that incorporation of prebiotics and papaya pulp in synbiotic shrikhand significantly influenced sensory and physicochemical properties of the final product. Likewise, studies on fruit peel incorporated shrikhand demonstrated enhanced antioxidant potential along with acceptable organoleptic quality at optimized levels of incorporation.
 
Colour attributes
 
The colour characteristics of shrikhand samples supplemented with varying concentrations of pomegranate peel powder (PPP) were evaluated using Hunter Lab colour coordinates: L* (Lightness), a* (Red-green axis) and b* (Yellow-blue axis). The results revealed significant alterations in all three colour parameters with increasing levels of PPP, as presented in Table 2.


 
Lightness (L*)
 
The reduction in L* values with increasing PPP incorporation is illustrated in Fig 2A significant decline (p<0.05) in the L* values was observed with increasing PPP concentration in shrikhand formulations. The L* value dropped from 84.93 in T₁ (control) to 62.96 in T₅ (4 part of PPP), indicating a gradual darkening of the product. This reduction in lightness can be attributed to the presence of high levels of Polyphenolic compounds in pomegranate peel, such as tannins and flavonoids, which are known to impart darker hues when incorporated into food matrices. Polyphenols, especially in dried peel form, often leading to the formation of brown pigments, during processing and storage, thereby lowering the lightness index. These findings align with those reported by Thorat (2018), who observed a similar decrease in lightness in dairy products fortified with polyphenol-rich plant extracts. Additionally, Kupnik et al., (2021) demonstrated that the addition of phenolic-rich powders, including pomegranate peel, resulted in significantly darker shades in yogurt, cheese and other fermented milk products.


 
Red-green coordinate (a*)
 
The increase in redness (a* values) with increasing PPP level is presented in Fig 3. The a* value, which quantifies the red-green colour dimension, increased markedly from -1.29 in T₁ to 6.38 in T₅, suggesting a pronounced shift toward redness with higher PPP inclusion. This positive shift in a* values can be primarily attributed to the presence of anthocyanins, natural water-soluble pigments abundant in pomegranate peel. Anthocyanins are known for their pH-sensitive colour transformations and are responsible for red to purple hues in food systems. The intensification of redness was consistent with findings by Al-Zoreky (2009), who reported that dairy products enriched with pomegranate derivatives exhibited increased a* values due to the anthocyanin content. The cumulative effect of these pigments, along with potential interactions between milk proteins and phenolic compounds, might have further enhanced the reddish tone in the treated shrikhand samples.


 
Yellow-blue coordinate (b*)
 
The increase in b* values indicating yellow-brown coloration is shown in Fig 4. The b* value, indicative of the yellow-blue chromatic spectrum, increased significantly (p<0.05) from 14.93 in T₁ to 31.42 in T₅, demonstrating a strong trend toward yellowness or yellow-brown coloration. This change was primarily attributed to the accumulation of tannins and other polyphenolic constituents in the PPP, which, upon interaction with milk components, contribute to non-enzymatic pigment development. Furthermore, the natural pigments inherent in PPP, along with its oxidative stability, enhance colour development during storage. Daoutidou et al., (2021) reported comparable findings in meat and dairy matrices fortified with PPP, noting that the powder not only intensified the yellow-brown hues but also imparted an appealing natural tint to the products.


 
Overall colour trend
 
The overall shift in L*, a* and b* values indicates a progressive darkening and enrichment in red-yellow tones with increased PPP addition. These visual modifications are considered favorable from a functional food perspective, as consumers often associate darker colours with higher antioxidant content and natural ingredients. However, the extent of colour change must be balanced to ensure it does not adversely impact sensory acceptability.  The trend similarly found in findings of Altunkaya et al., (2013) that did spectrophotometric measurement of bread enriched with pomegranate peel showed, with increasing levels of PP addition, L*values decreased, while a* and b* values increased, showing that PP affected bread color. These observations were indicative of a loss in brightness of the bread caused by PP.

The study confirmed that pomegranate peel powder (PPP) can be effectively utilized as a functional ingredient in shrikhand to improve its nutritional profile while maintaining consumer acceptability. Sensory evaluation revealed that shrikhand fortified with 1 and 2 part of PPP retained favorable organoleptic characteristics, including flavour, body and texture, mouthfeel, colour and appearance and overall acceptability. Treatments beyond 2 parts of PPP significantly compromised sensory quality due to the bitter and astringent taste and altered mouthfeel caused by the fibrous nature of PPP.  Instrumental colour analysis further demonstrated that increasing levels of PPP led to darker, reddish-brown hues, which, while acceptable at lower concentrations, reduced visual appeal at higher levels. These colour modifications were attributed to natural polyphenolic compounds such as anthocyanins and tannins present in PPP. The optimal range for PPP incorporation was found to be 1 and 2 parts, which offered a balance between functional benefits and sensory quality. Thus, PPP represents a sustainable, value-added ingredient with the potential to convert food processing by-products into health-promoting dairy foods. Its inclusion aligns with the growing consumer demand for clean-label, functional enriched products. Future work could explore the use of natural flavour-masking agents or enzymatic treatments to enhance sensory appeal at higher PPP concentrations.
 
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
 
All procedures and handling techniques for experiments were approved by the Committee of Experiment.

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.