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ThesisItem Open Access EXTRACTION AND CHARACTERIZATION OF ESSENTIAL OIL FROM NUTMEG FRUIT FLESH FOR ITS UTILIZATION AS AN ANTIMICROBIAL COATING IN PANEER(VERGHESE KURIEN INSTITUTE OF DAIRY AND FOOD TECHNOLOGY MANNUTHY, THRISSUR, KERALA VETERINARY AND ANIMAL SCIENCES UNIVERSITY, 2023-02-09) VYSHAK V L; Dr. Rahila M. PPaneer is an indigenous coagulated milk product, but it is highly perishable with a limited shelf- life like other indigenous dairy products. Its shelf life was reported to be only six days under refrigeration, though its freshness is lost within three days. The spoilage of paneer occurs mainly due to the growth of microorganisms, which bring about various physico-chemical changes. In the present study attempts were made to increase the shelf-life of paneer at refrigerated storage by the application of essential oil coating prepared from nutmeg fruit flesh. The essential oil is prepared from nutmeg fruit flesh by steam distillation method. Physico-chemical and bio functional properties of essential oil was determined. The specific gravity of the essential oil was found to be 0.903. The refractive index of essential oil was 1.4772. The acid value and total poly phenolic value of essential oil was 3.36 and 4.04 mg GAE/g respectively. The extracted essential oil also found to have antimicrobial and antioxidant activity. The percentage radical scavenging activity of essential oil was 66.66%. Antimicrobial property of the essential oil was assessed against the indicator organisms Staphylococcus aureus and Escherichia coli by performing the agar well diffusion assay. The extracted essential oil exhibited inhibitory action against both the indicator organisms. The shelf life of samples coated with essential oil packaged in LDPE pouches had more shelf life than the control paneer as the coated paneer kept well for 9 days while the control paneer was spoiled after the 6th day of refrigerated storage. The paneer with essential oil coating obtained satisfactory sensory scores.ThesisItem Open Access EVALUATION OF PHYSICO-CHEMICAL, NUTRITIONAL AND BIO-FUNCTIONAL CHARACTERISTICS OF MILK FROM VECHUR AND KASARGOD DWARF BREEDS OF CATTLE(VERGHESE KURIEN INSTITUTE OF DAIRY AND FOOD TECHNOLOGY MANNUTHY, THRISSUR, KERALA VETERINARY AND ANIMAL SCIENCES UNIVERSITY, 2022-12-13) SANA JOSE K; Dr. Rachana C.RVechur and Kasargod Dwarf cattle are indigenous to the state of Kerala, India. Vechur cattle is registered as an indigenous breed as per National Bureau of Animal Genetics Resources (NBAGR) whereas Kasargod Dwarf is labelled as ‘non-descript’. Limited information is available on the compositional characteristics of milk from these cattle. In the present study, pooled milk samples of Vechur and Kasargod Dwarf cattle were collected for physicochemical, nutritional and bio-functional analysis. The gross compositional analysis of milk revealed that Vechur milk had higher concentration of total solids, fat and ash compared Kasargod Dwarf milk, but protein content was more in the latter. This observation was reflected in the titrable acidity values as well. The nutritional analysis of milk samples unveiled the fact that Kasargod Dwarf milk had higher concentration of Vitamin C, D and E content compared to Vechur cow milk, whereas Vitamin A concentration was higher for the latter. The Kasargod Dwarf milk was also shown to have lower cholesterol content (290.44±3.53) than Vechur cow milk (350.75±3.22). The bio-functional characteristics such as antioxidant activity, fatty acid profile and SDS-PAGE protein fractionation was also carried out. The antioxidant activity (percent radical scavenging activity) was observed to be 44.13 and 48.85% for Vechur and Kasargod Dwarf milk, respectively. The milk from Kasargod Dwarf cattle exhibited higher concentration of unsaturated fatty acids. The milk proteins were resolved using SDS-PAGE and the following fractions were identified: Lactoferrin (Lf) (76 kDa), immunoglobulin (Ig) (66 kDa), α-S1caseins (23 kDa), α-S2caseins (21 kDa), β-casein (24 kDa), β- lactoglobulin (18 kDa) and α-lactalbumin (14 kDa). The overall nutritional and bio-functional parameters revealed that Kasargod Dwarf milk has better characteristics than Vechur cow milk. However, to prove the worth of consuming and asserting the beneficial health effects of milk from indigenous breeds, a comprehensive clinical or animal study is required.ThesisItem Open Access EFFECT OF DIFFERENTIAL HEAT TREATMENTS ON BIOFUNCTIONAL PROPERTIES OF BIOPEPTIDES IN FERMENTED GOAT MILK(VERGHESE KURIEN INSTITUTE OF DAIRY AND FOOD TECHNOLOGY MANNUTHY, THRISSUR, KERALA VETERINARY AND ANIMAL SCIENCES UNIVERSITY, 2022-12-20) AISWARYA V G; Dr. Rachana C.RGoat milk, which is claimed to have medicinal value, is one of the naturally occurring functional foods and is generally used as a substitute for human milk. However, goat milk proteins are more sensitive to heat treatment, and no data are available in the literature about the impact of thermal processing on biopeptides. Therefore, in the present study, the effect of differential heat treatments on the biofunctional properties of biopeptides in fermented goat milk was investigated. Three heat treatments were used in the analysis namely, 72°C/15sec, 85°C/10min, and 121°C/15min. The physicochemical analysis of this differentially heat-treated goat milk showed that protein content and lactose content of milk heated to 121°C/15min were significantly lower. The pH of milk decreased significantly with heating to around 6.25 in the case of milk heated to 121°C/15min. Antioxidant activity was highest in milk heated to 121°C/15min with an average of 51.18% RSA. Milk heated to 85°C/10min showed 35.47% inhibition of the ACE enzyme. Antimicrobial activity was observed against E.coli in the case of 85°C/10min. SDS-PAGE was used to compare protein fragments. Seven bands that were clearly visible on the electrophoretogram of raw milk showed disappearance with the intensity of heating. The fermentation and subsequent storage analysis on the 0th, 7th, 14th, and 21st day showed that both biofunctional and physicochemical property was significantly changed. The pH and carbohydrate content gradually decreased while acidity gradually increased with the storage period. Antioxidant activity was highest in fermented milk initially heated to 121°C/15min, which showed 70.20% RSA on the 21st day. Antihypertensive activity and antimicrobial activity were highest in fermented milk initially heated to 85°C/10min. Protein profiling in all three cases of fermentation showed that as storage time rose, the intensity of the β-Lg band in samples decreased. By the sensory evaluation of fermented product from three heat treatments, it was found that fermented product made from milk initially heated to 121°C/15min had better organoleptic properties and a pleasant flavour. It may be inferred that the biofunctional properties can be changed with suitable heat treatment and fermentation, which will help produce milk products with improved sensory qualities that are hypoallergenicThesisItem Open Access EXTENT OF DEGRADATION OF GHEE ON REPEATED USE AS COOKING MEDIUM(COLLEGE OF DAIRY SCIENCE AND TECHNOLOGY MANNUTHY, THRISSUR, 2022-03-04) ALEENA. K. S.; Divya M. PThe high temperature cooking process creates a series of complex chemical reactions in oil and affects the sensory as well as functional properties of foods and the oil. The reuse and repeated heating of cooking oil results in oil deterioration leading to adverse health effects. There is shortage of Indian studies high- lighting the extent of degradation of cooking oils especially ghee on repeated use as cooking medium. The aim of the present project was to check the extent of thermal degradation in ghee over other edible oils on repeated use as cooking medium. Coconut oil and sunflower oil were selected for comparison with ghee, due to their popularity in Kerala cuisine. The oils were subjected to two types of treatments in which, influence of high temperature as well as time was studied and it was found that heating at constant temperature for long time (180°C for 6 hours) caused more oil quality deterioration compared to high temperature heating (300°C). Compared to ghee and sunflower oil, coconut oil had highest stability against oxidation. Paneer was fried in different cooking oils as well as Ghee. The frying process was repeated with same sample of oils and ghee, and samples after each frying were analysed to study the interactions occurred during frying processes. Ghee and sunflower oil had least interaction with food upon repeated heating. Smoke point of all the selected oils and ghee was determined to analyse the suitability for high temperature cooking and deep fat frying. The safe extent of repeated usage of ghee and other cooking oils were determined by analysing the fatty acid composition (GC-MS), Total polar compounds (ATR- FTIR and Testo 270) and oxidation products (Fluorescence spectroscopy). It was recommended that up to 4 repeated heating, coconut oil, sunflower oil and ghee are safe for consumption.ThesisItem Open Access DEVELOPMENT OF A TECHNIQUE FOR DETECTION OF PRESENCE OF COW MILK IN GOAT MILK(COLLEGE OF DAIRY SCIENCE AND TECHNOLOGY MANNUTHY, THRISSUR, 2020-11-01) VANDHANA P S; Divya M. PAdulteration of Goat milk in terms of mixing with Cow milk has emerged to be a serious issue in the recent years. The higher price and nutritional value coupled with limited availability of the former serves as the driving factor for the mixing of relatively cheaper, easily available cow milk to goat milk. The current available analytical techniques for the detection of presence of cow milk in goat milk are highly sophisticated, laborious, complex and time consuming which cannot be adopted at the basic level by private goat milk producers. So the development of a simple rapid laboratory technique for the same which can be applied at the farm and society level is a great need in the present days. This study was conducted using pure goat milk, pure cow milk and cow milk mixed with goat milk at different proportions of 25 percent, 50 percent and 75 percent. The physico chemical and compositional properties of samples were analyzed and a significant variation between the samples was observed in terms of fat and chloride content. The ethanol stability was checked for the samples and found out that goat milk has lower ethanol stability compared to bovine milk and it improved by addition of cow milk. A blue colour which varies proportionately in intensity from light blue for pure goat milk to dark purple by increased addition of cow milk was developed by addition of Bromocresol purple and was verified using colorimeter. The addition of Seliwanoffs reagent to the above said samples led to the development of coagulum with significant differences in appearance such as a completely dispersed coagulum in case of goat milk and a clearly settled coagulum on top portion for cow milk. The rate of settlement of coagulum to the top increases with increase in content of cow milk in goat milk. The above stated differences may be considered as the basis for detection of presence of cow milk in goat milk. Further the Scanning Electron microscopy study of coagulum was carried out and fatty acid profile of samples was analysed using GC-MS.ThesisItem Open Access EFFECT OF TEA POLYPHENOLS ON CALCIUM IN MILK(COLLEGE OF DAIRY SCIENCE AND TECHNOLOGY MANNUTHY, THRISSUR, 2022-03-30) ARYA P.R; Athira SAccording to the International Osteoporosis Foundation, 8.9 million people are suffering from osteoporosis worldwide. Milk is a complete food with a good source of calcium. Generally, in India, people hesitate to drink milk as such and they like to have it as a beverage such as tea. So it is very essential to investigate the effect of tea polyphenol on calcium in milk during milk tea preparation. In the present study, milk tea was prepared by adding 2% tea powder in boiled milk and strained after 2 minutes of brewing. The effect of processing parameters such as water: milk ratio, pH, brewing time, the concentration of tea powder, type of milk and amount of sugar on interactive behaviour of tea polyphenols with calcium were also analyzed. The result showed a significant reduction (p-value <0.05) in the calcium and protein content of milk tea beverage (926.24±0.74 ppm and 2.89±0.01 %) compared with the milk (1409.1±0.2 ppm and 3.42±0.009 %). The polyphenol and tannin content was also reduced in milk tea (13.93±0.021 mg GAE/ml and 1.42±0.014 mg TAE/ml) compared with black tea (15.32±0.12 mgGAE/ml and 3.21±0.011 mgTAE/ml). The processing parameters have a positive correlation with interactive behaviour and leads to the reduction in the calcium content of the final brew. The bioavailability of calcium present in the tea beverage was also evaluated by simulated gastrointestinal model. It showed that the bioavailability of calcium gets reduced when milk tea (19.14±04%) was prepared as compared with milk (25.45±0.009%). Hence it is conformed and suggested that consumption of milk is better than milk tea beverage for getting maximum amount of nutrients specially calcium from milk.ThesisItem Open Access EFFECT OF INCORPORATION OF ORGANOGELS ON PHYSICOCHEMICAL CHARACTERISTICS OF YOGHURT(COLLEGE OF DAIRY SCIENCE AND TECHNOLOGY MANNUTHY, THRISSUR 6, 2022-02-16) HELNA PIOUS; Divya M.PThe effect of incorporation of canola oil organogels prepared with sunflower wax and candelilla wax on physicochemical properties of yoghurt were studied in this work. The key objectives of the work were to compare the characteristics of organogels prepared from plant waxes (Candelilla and Sunflower) and Canola oil combinations, and also to study the physicochemical, microbial, sensory, textural and nutritional characteristics of yoghurt incorporated with organogels. Initially organogels at different plant wax concentrations were prepared and analyzed. The critical concentration of candelilla and sunflower wax was 2% and 1% respectively. Sunflower wax exhibited higher gelling ability whereas the oil binding capacity was higher for candelilla wax. A stable gel was formed by candelilla and sunflower wax at 4% and 3% respectively and organogels at these concentrations were incorporated in yoghurt. There were no impact in physicochemical characteristics like acidity and pH of yoghurt up to 3% addition of organogels. At the same time, a significant difference was observed in fat, protein, lactose and syneresis in yoghurt. Addition of organogels led to a remarkable decrease in syneresis compared to that of control yoghurt .Up to 3% addition of organogel, matched with the sensory score of control yoghurt. The lactic acid bacteria count of all samples were above 107 CFU/g, and yeast and mould count of all samples were within the FSSAI standards up to 14 days of storage. There was an improvement in textural characteristics like hardness and cohesiveness by addition of organogels to yoghurt. GC-MS analysis for fatty acids exposed a remarkable increase in unsaturated fatty acids in organogel incorporated yoghurt sample. Findings of this study open up the potential of organogels in food products to improve the textural and nutritive properties.ThesisItem Open Access PHYSICO-CHEMICAL CHARACTERISATION OF PANEER TO DETECT THE USE OF INORGANIC ACIDS AS COAGULANT(COLLEGE OF DAIRY SCIENCE AND TECHNOLOGY MANNUTHY, THRISSUR, 2022-02-15) SHARATH S; Divya M PThe main factors that affect the different sensory and physico-chemical characteristics of paneer are type and concentration of coagulants used. Commonly used coagulants are citric acid and lactic acid. As per the report published by Times of India (22nd August,2018) the unscrupulous addition of inedible non food grade coagulants like sulfuric acid, HCl etc. for paneer preparation is a matter of great concern in recent times. The consumption of such spurious or synthetic Paneer is highly lethal for health as it causes severe intestinal and stomach infection, which can also be cancerous. The detection of such fraudulent practices adopted by the manufacturers is very much important. Therefore, the current study aimed at accessing the effects of inorganic coagulants on the physico - chemical and sensory properties of Paneer that determines the quality and consumer acceptance. The paneer was prepared from buffalo milk by direct acidification process using 1 percentage citric acid, 1 percentage lactic acid, 1 percentage H2 SO4, Concentrated H2SO4, 1 percentage HCl, Concentrated HCl. The physico-chemical, compositional and coagulation characteristics of prepared paneer samples and the resultant whey were analyzed using standard methods. The coagulation time and amount of coagulant required varied significantly (5 percentage level) between organic and inorganic coagulants. The yield was higher when concentrated sulfuric acid was used. The texture analysis studies showed that the hardness of paneer prepared using concentrated sulfuric acid was lesser compared to other coagulants and this agreed with the higher fat content showed by the same sample. The sensory properties of the prepared samples showed negligible difference in between them. The storage studies of the paneer samples were conducted at refrigerated temperature for 12 days with three days regular interval.
