According to FSSAI, paneer is the product obtained from buffalo or cow milk combination of both by precipitation with citric acid, lactic acid or sour milk. On the dry matter basis, It shall milk fat contain shall not be less than 50% and not contain more than 70% moisture. Paneer is made up of fat and protein, colloidal materials and insoluble salts and also part of the moisture of the original milk, which contains whey protein, lactose, vitamins, soluble salts and other milk components (Kanawjia and Singh, 1996). Buffalo milk has better physico-chemical qualities than cow milk, which contributes to its high-quality paneer. As compared to cow milk, buffalo milk has lesser voluminosity and higher concentrations of solid fat, calcium, phosphorus, casein and larger fat globules and casein micelles (Sindhu, 1996). Paneer is a protein rich dairy product and fulfills the protein requirement of most vegan people of India. But because of its high cost many people cannot afford it and refrain from consuming it daily (Chaudhari et al., 2025). The amount of minerals and casein i.e., phosphorus and calcium were impact on rubbery and firm body to buffalo milk paneer. Paneer is a highly perishable product in nature and have restricted shelf life, due to its high moisture content (Arora and Gupta, 1980).
       
Turmeric is broadly used as a food preservative, spice and colouring ingredient in India, China and South East Asia. It has been typically used in traditional medicine as a household medicine for various diseases, including cough, biliary disorders, anorexia, hepatic disorders, diabetic wounds and sinusitis. Curcumin, the main and most important yellow bioactive component of turmeric which has a wide range of biological actions. It includes following   biological actions which are most important and they are anti-inflammatory, antioxidant, anti-mutagenic, anti-carcinogenic, anticoagulant, anti- fertility, anti-diabetic, anti-bacterial, anti-fibrotic  anti-fungal, antiviral, anti-venom and antiulcer and hypo cholesterol (Chattopadhyay et al., 2004). Black pepper is known as the ‘king of spices’  because of its pungent quality. It is used throughout the world as medicinal and preservative agent. It has cleansing properties and antioxidant and helps in enhancing bio-availability of other herbs. It is natural antioxidant, act as anti-inflammatory, anticancer, antiperiodic and antipyretic. It can also lower the body cholesterol levels (Himabindu and Arunkumar, 2017). Now a days, there has been increasing demand for herbal food which is free from chemical and provide various nutrients and also their effect on human health. The consumers are also demanding food products which having long shelf life and free from contamination.

The research on the preparation of herbal paneer with incorporation of black pepper and turmeric powder was conducted in the Department of Animal Husbandry and Dairy Science, College of Agriculture, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani (M.S.) India during M.Sc. dissertation work 2019-2021.
       
The whole, fresh ,clean,  buffalo milk was obtained from buffalo unit, college of Agriculture, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani (M.S.). Turmeric, black pepper, muslin cloth obtained from local market. Different equipment viz, paneer blocks, stirrer, thermometer were available in the department.
       
Herbal paneer was prepared from buffalo milk with different combinations of turmeric and black pepper powder in which the levels of black pepper (0.1, 0.2, 0.3 per cent) and turmeric powder (0.1 per cent) constant in each treatment. The samples of paneer were kept at a refrigeration temperature of 7±2°C. The samples were examined for mould and yeast counts in accordance with IS: 5403 (1969) and bacterial counts in accordance with IS: 5402 (1969).
 
Procedure
 
Paneer was prepared by following the method of Aneja et al., (2002) with minor modifications. Fresh buffalo milk was filtered through a muslin cloth to eliminate dust and other foreign particles. The filtered milk was heated to 90°C and held at this temperature for 5 minutes, after which it was cooled to 70°C. The cooled milk was coagulated by slowly adding 1% citric acid solution with gentle and continuous stirring until complete coagulation took place, producing a firm curd and clear whey. The whey was separated from the coagulated mass by draining it through a muslin cloth. The freshly formed coagulum was transferred into a rectangular stainless-steel hoop fitted with small perforations at the base to facilitate whey drainage. The coagulated mass was compressed under a pressure of 3.0 kg/cm² for 20 minutes to obtain the desired texture. The pressed paneer block was then cut into uniform pieces and immersed in chilled water maintained at 5°C for 2 to 3 hours. After cooling, the paneer pieces were removed from the water, allowed to drain, wrapped in parchment paper and stored under refrigerated conditions until further analysis or use.
       
As per the requirement of research, the procedure of paneer was slightly modified from standard procedure given by Aneja et al., (2002) (Flow Chart 1). 


 
Sensory evaluation of paneer
 
The sensory quality of paneer was evaluated by a trained panel consisting of 7 members from the technical staff of the Department of Animal Husbandry and Dairy Science, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani (M.S.). The samples were assessed using a 9-point hedonic scale for sensory attributes including flavour, colour and appearance, body and texture and overall acceptability following the method described by Gupta (1976).
 
Statistical analysis
 
The data obtained from the experiment were statistically analyzed using Analysis of Variance (ANOVA) under a completely randomized design (CRD) following the procedure described by Panse and Sukhatme (1967).

Shelf life of paneer at refrigerated temperature
 
The shelf life of herbal paneer was assessed at refrigerated temperature (7±2°C) on sensory score by judges and data of average score analyzed and depicted in Table 1.


 
Colour and appearance
 
It was observed that the colour and appearance scores of paneer decreased during the storage period from 0 to 12 days. The scores declined from 8.51 to 6.93, 8.83 to 7.01, 8.10 to 6.91 and 7.35 to 6.33 for treatments T0, T1, T2 and T3, respectively, as presented in Table 1. The results indicated a continuous reduction in the colour and appearance scores of paneer throughout the storage period. Among all the treatments, T1 recorded the highest colour and appearance scores, decreasing from 8.83 to 7.01 during storage.
 
Flavour
 
The organoleptic evaluation of fresh paneer samples, including both control and treated samples, revealed variations in flavour scores ranging from 8.62 to 5.26, 8.86 to 7.53, 8.15 to 6.45 and 7.53 to 5.41 for treatments T0, T1, T2 and T3, respectively, as presented in Table 1. The results indicated that increasing the levels of turmeric and black pepper powder in paneer reduced its flavour acceptability. A continuous decline in flavour scores was observed throughout the storage period until the samples became unacceptable. However, paneer supplemented with 0.1% black pepper powder and 0.1% turmeric powder (T1) remained acceptable up to the 12th day of refrigerated storage. The present findings are in agreement with those of Singh et al., (2018), who reported comparable flavour scores for paneer prepared from buffalo milk with the incorporation of mint. Similar observations were also reported by Buch et al., (2014), who found that the addition of turmeric at levels exceeding 0.6% significantly reduced the sensory scores of paneer. They further reported that incorporating 0.6% turmeric extended the shelf life of paneer up to 12 days when stored at 7±1°C.
 
Body and texture
 
Body and texture scores of control and treated paneer during storage are presented in Table 1, which showed that scores significantly decreased during storage at refrigeration temperature. The treatment given to paneer influence the body and texture attribute (Table 1). However treatment T₁ (8.82 to 7.35) remain superior over T₀ (8.60 to 6.96), T₂ (8.13 to 6.57) and T₃ (7.30 to 5.45). Body of control and treated paneer become soft and sticky: probability may be due to slime production by microbes. Mishra et al. (2021) studied that addition of black pepper extract on shelf life of paneer and found that improved shelf life of black pepper treated paneer (12 days) as compared to control paneer (8 days).
 
Overall acceptability
 
The overall acceptability scores of the control and black pepper and turmeric powder treated paneer samples during refrigerated storage are presented in Table 1. The results showed a significant reduction in overall acceptability during the storage period. The average scores decreased from 8.57 to 6.38, 8.83 to 7.29, 8.12 to 6.64 and 7.39 to 5.73 for treatments T₀, T₁, T₂ and T₃, respectively, by the 12^th day of refrigerated storage. The extended shelf life of black pepper-treated paneer may be attributed to the low storage temperature, the antimicrobial properties of black pepper and the combined effect of these factors. Similar findings were reported by Kapoor (2014), who observed that the essential oil of black pepper enhanced the shelf life of orange juice. The sensory attributes, namely colour and appearance, flavour, body and texture and overall acceptability gradually declined throughout the storage period. A continuous decrease in sensory scores was observed from day 0 to day 12. Treatments T₂ and T₃ received comparatively lower scores, which may be due to the softer texture of paneer resulting from the higher level of black pepper incorporated during storage.The present results are in accordance with the findings of Patil and Sonawane (2022), who studied the effect of refrigerated storage (7±2°C) on the chemical, organoleptic and microbial qualities of paneer. They also reported a gradual decline in the scores for colour and appearance, body and texture, flavour and overall acceptability up to the 12^th day of storage.
       
Similar result found by Sarnaik et al., (2021) who studied that addition of black pepper at the rate 0.25, 0.50 and 0.75 per cent in paneer changes colour and appearance, flavour, body and texture and overall acceptability from 0 to 9 days significantly. The overall acceptability of all the samples of paneer was within desirable range except slightly poorer for control paneer as compared to others and shows natural look when packed in different packaging material.
       
From above data it was found that increase in the combination of turmeric and black pepper powder, shelf life of paneer on the basis sensory evaluation declined slightly, it might be due to black pepper pungency and colour of black pepper.
 
Microbial load of paneer
 
The results found from the changes in sensory attributes during storage suggested that treatment T₃ (0.1 per cent turmeric powder and 0.3 per cent black pepper powder) as the best to extend the shelf life of paneer. Therefore, the effect of this treatment on the microbial quality of herbal paneer was evaluated. Fresh as well as stored paneer samples were analyzed for microbial parameters, including standard plate count, yeast and mould count and coliform count during a storage period of 12 days.
       
From the Table 2, it was observed that the SPC count of control paneer increased to 3.21 to 6.51×10³ cfu/g for 0 to 12^th days. For treatment T₁ count ranges from 3.16 to 6.29×10³ cfu/g, T₂ count 3.05 to 6.03×10³ cfu/g and T₃ 2.83 to 5.80×10³ cfu/g for 0 to 12 days. Incorporation of black pepper and turmeric powder in paneer resulted significant decrease in SPC count of paneer.


       
The combinations of spices i.e., black pepper and turmeric powder increased as compared to control paneer significantly lower Standard plate count and yeast and mould  count during storage. 
       
Kumari et al., (2025) studied that microbial stability of paneer spread incorporated with ginger and garlic paste with different combination and found similar results with this findings upto 12^th days .
       
Gupta (1985) studied that the SPC of fresh sample of market paneer ranged from 2.5×10³ to 3.5×10⁵ cfu/g (which is average initial count of 3.0×10⁵). Kumar and Bector (1991) found the initial counts of control 3.0×10³ increased to 2.8×10⁵ cfu/g on day four and 9.0×10⁶ cfu/g on day seven during storage at 15°C.
       
From the Table 2 it was observed that the yeast and mould count of control paneer increased to 2.3 to 4.85×10³ cfu/g for 0 to 12^th days. For treatment T₁ count ranges from 2.1 to 4.42×10³ cfu/g, T₂ count 1.8 to 4.1×10³ cfu/g and T₃ count 1.6 to 3.90×10³ cfu/g for 0 to 12 day. The yeast and mould count decreased from treatment T₀ to T₃ for 0 to 12 days.
       
The above findings are more or less similar with the findings of Buch et al., (2014) who studied that addition of turmeric at different level the SPC count decrease slightly as compared to control paneer and also found that the addition of turmeric slightly increase the yeast and mould count up to 12 days during storage. Venkateswarlu et al. (2003) also reported that  yeast and mould count found for paneer was 2.45 per g. Coliform count not detected for T₀, T₁, T₂ and T₃ treatment at 0 and 12 day.

From the present work, it can be concluded that incorporation of turmeric powder and black pepper in paneer significantly influenced the sensory quality and microbial load during refrigerated storage. Among the different treatments, paneer prepared with 0.1% turmeric powder and 0.1% black pepper on the basis of milk (T₁) showed the highest sensory scores for flavour, colour and appearance, body and texture and overall acceptability throughout the storage period.
       
The sensory scores for all treatments gradually decreased during storage; however, treatment T₁ remained acceptable up to 12 days under refrigerated storage (7±2°C), whereas, the control paneer showed lower acceptability. Microbiological analysis indicated that the standard plate count and yeast and mould count increased during storage, but the increase was comparatively lower in the treated samples than in the control. Coliform bacteria were not detected in any treatment during the storage period.
       
The improved shelf life of herbal paneer may be attributed to the antimicrobial and antioxidant properties of turmeric and black pepper, along with the effect of refrigerated storage. Therefore, incorporation of 0.1% turmeric powder and 0.1% black pepper can be recommended for the preparation of herbal paneer to enhance shelf life and maintain acceptable sensory quality without the use of chemical preservatives.

The authors declare no conflict of interest.