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Anand Agricultural University, Anand

Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.

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Subject: Dairy Chemistry × Start date: 1990 × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    DEVELOPMENT OF NITROGEN DISTRIBUTION BASED APPROACH TO DETECT ADULTERATION OF MILK WITH NON-PROTEIN NITROGENOUS COMPOUNDS
    (DAIRY CHEMISTRY DEPARTMENT SHETH M. C. COLLEGE OF DAIRY SCIENCE ANAND AGRICULTURAL UNIVERSITY ANAND, 2017) SHAIKH AHESANVARISH ISMAILBHAI; Dr. K. D. Aparnathi
    Milk is a wholesome food for people of all age groups ranging from infants to old. However, image of milk as food is tarnished due to menace of adulteration. In past few decades adulteration of natural milk with a chemically formulated milky fluid (synthetic milk) has been as a matter of serious concern due to its potential harmful effects on human health. This fluid expertly prepared so as to imitate as natural milk prepared from refined oil, detergent, carbohydrates, non-protein nitrogenous compounds, salts and soda by dissolving/dispersing calculated amount of different ingredients of the formulation using water as a medium. Hence it easily passes the routine tests (fat and lactometer reading) carried out at the collection centres.
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    ThesisItemOpen Access
    STANDARDIZING CONDITIONS FOR PILOT SCALE PRODUCTION AND STORAGE OF BUFFALO SKIM MILK DAHI USING STREPTOCOCCUS THERMOPHILUS: SOME CHEMICAL ASPECTS
    (AAU, Anand, 1990) Thakuria, Hemanta; Patel, S. M.
    This investigation was planned and carried out to elucidate the effects of level of total solids of buffalo skim milk and inoculation with three specific strains of Streptococcus thermophilus on some of the quality attributes of dahi. The total solid content of buffalo skim milk was adjusted to 10.0 (T1), 12.5 (T2) and 15.0 (T3) per cent using condensed buffalo skim milk and inoculated with D3(C1), MD2 (C2) and MD8 (C3) strains of Streptococcus thermophilus. Incubation was done at 40 ± 1°C till the desired acidity of 0.75 (% lactic acid) was obtained. Samples were then stored at 5 t o 7°C for about 12 h after which the samples were considered to be at 0 h of storage (fresh product). To study the physico-chemical and organoleptic changes taking place and also to study the shelf - life of the dahi under room temperature, the samples were stored at 37 ± 1°C and analysed at the interval of Oh, 12h, 24h and 48h. Similarly for study under refrigerated condition samples were stored at 5 t o 7°C and analysed at the interval of Od, 6d, 12d and 18d of storage.
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    ThesisItemOpen Access
    STUDIES ON ENHANCING THE SHELF LIFE OF KHOA
    (AAU, Anand, 1999) Sharma, Pragati; Aparnathi, K. D.
    A study for enhancement of shelf life of khoa was undertaken in four phases. In phase one, suitable packaging materials were selected; in phase two, the effect of vacuum packaging was studied and phase three comprised evaluation of the effect of different physical and chemical treatments and storage studies were conducted at 32±1°C. The most effective treatments from the three phases were selected and in the final phase khoa was given the best treatment, packed in the best packaging material under vacuum and shelf life was studied at 32±1°C as well as 4±2°C. Packaging materials studied in the phase I include (A) LDPE; (B) LD:LLD; (C) HD:LD:HD;" (D) HMHD; (E)PET:Aluminium foil:LDPE; and (F) PET:Aluminium foil:(LD:LLD). Three packaging materials A, D and E were selected and then in the phase II, influence of vacuum packaging on the shelf life of khoa was observed. In phase III, the effect of thermization (Tn); microwave exposure (TMW); incorporation of potassium sorbate (TKS) and addition of sugar (Ts) for improvement in the shelf life of khoa was assessed. Finally, in phase IV, the effects of the best packaging material, vacuum packaging and TKS were combined and their performance was compared with the samples packed under atmospheric pressure without any treatment. The samples were stored at room temperature (32+1 °C) as well as at refrigerated temperature (4+2°C). The fresh khoa samples were analysed for their chemical composition and microbiological quality. Deterioration during storage was monitored by measuring changes in chemical parameters viz. titratable acidity, free fatty acids content and tyrosine value. Microbiological changes were estimated as total viable count, yeast and mold count and coliform count. Fresh as well as stored samples of khoa were evaluated for their sensory attributes by a panel of 10 judges. During storage the samples were analysed daily for 3 days in Phase I and II and 4 days in Phase III. In the fourth phase the samples stored at 32+1 °C were analysed on 1, 3, 5 and 7 day and samples stored at 4±2°C on 1, 3, 5, 7, 14 and 21 day. One of the samples (with added potassium sorbate and packed under vacuum) kept at 4+2°C was analysed upto day 45. Four replications were carried out in each phase and the data were analysed statistically. Statistical analysis using Randomized Block Design indicated that the packaging materials included in the study had no significant effect on the shelf life of khoa. Regression analysis of the data, however, showed that rate of spoilage was better controlled by aluminium foil laminates closely followed by HMHD. Vacuum packaging significantly (P<0.05) reduced the rate of lipolysis and microbial growth (total viable count and yeast and mold count). Similarly, sensory (flavour and overall acceptability) scores were also found to be significantly (P<0.05) higher during storage under vacuum. However, vacuum packaging hadV no significant effect on rate of proteolysis, titratable acidity and coliform count. Various treatments (TH, TMW, TKS and Ts) significantly (P<0.05) increased the shelf life of khoa. However, Ts and TKS were found to be better than TMW and TH. Simple refrigerated (4±2°C) storage increased the shelf life of khoa to about 14 days, whereas, a combination of vacuum packaging, incorporation of potassium sorbate and low temperature storage increased the shelf life to about 45 days.
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    ThesisItemOpen Access
    EFFECT OF ONION (Allium cepa Linn.) SKIN EXTRACT ON OXIDATIVE STABILITY OF GHEE
    (AAU, Anand, 1996) Jain, Aditya K.; Sharma, R. S.
    A study was carried out to elucidate the effect of addition of antioxidant principles of onion skin via a preextract on the oxidative stability of ghee. A composite sample of onion skin obtained from local vegetable market contained 9.56 per cent moisture, 0.79 per cent fat, 0.56 per cent protein, 8.35 per cent ash and 80.74 per cent carbohydrates as major constituents. It also contained 3.17 per cent total phenolics, 0.41 per cent water extractable phenolics and 0.015 per cent phospholipids. Fresh ghee manufactured in a commercial dairy by creamery butter method employing prestratification and clarified at 110°C without' any holding period was used for the study. The antioxygenic compounds of onion skin were extracted into methanol, dried and ground to get a fine powder which was added to ghee at a rate of 0.5 per cent (w/v). The mixture was kept at 40 ± 2°C for 12 h and then at 50 ± 2°C for about 3 h followed by decantation of clear ghee, the pre-extract. This pre-extract was finally added to ghee at the rate of 0 (T0, control), 10 (T1), 15 (T2) and 20 (T3) per cent levels constituting different treatments. For comparison, the last treatment was addition of butylated hydroxy anisole (BHA) at the legally permitted rate of 0.02 per cent (T4) . To monitor the effectiveness of the additions, peroxide value of all ghee samples was determined immediately after receiving the ghee and after every 48 h interval of storage at 80 + 2°C in a memmert type oven. The pre-extract contained on an average 21.3 mg per cent water extractable phenolic compounds. The water extractable phenolics content of ghee samples added with the pre-extract at various levels were in order : 3.580 mg/100 g (T3) > 2.894 mg/100 g (T2) > 2.211 mg/100 g (T1) > 1.106 mg/100 g (T4) > 0.843 mg/100 g (T0). The antioxygenic indexes were in the order : 1.22 (T4) > 1.19 (T3) > 1.17 (T2 and T1) > 1.00 (T0). From the results of this study, it is concluded that the antioxygenic compounds of onion skin can be extracted in a crude form using methanol, dried and ground to obtain a fine powder. Addition of these antioxygenic compounds in the form of pre-extract enhanced the oxidative stability of ghee. Addition of such pre-extract at all the levels studied in this experiment (10, 15 and 20 per cent, v/v) was found to be almost at par with addition of BHA at 0.02 per cent level. The phenolics present in the onion skin appear to be the main contributory factors in enhancing the oxidative stability of ghee. Quercetin and anthocyanin, the phenolic compounds reported to be concentrated in the onion skin are expected to be the principal antioxidants. Besides these compounds, carotene, Vitamin C and phospholipids/ phosphorus containing compounds of onion skin could also be responsible for part of the antioxidant effect observed.
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    ThesisItemOpen Access
    PHYSICO-CHEMICAL AND STORAGE CHARACTERISTICS OF MILK CHOCOLATES DEVELOPED FROM BUFFALO MILK, TABLE BUTTER AND ROASTED GROUNDNUTS
    (AAU, Anand, 1996) Sinha, Bibhuti Prasad; Patel, S. M.
    This study was undertaken to develop a simple process to manufacture milk chocolates by panning of batch method on the process based to manufacture caramel. Roasted groundnuts were added to ascertain economical viability of the product as well as to increase the protein content without adding any preservative, hydrogenated fat or cocoa butter. It was also planned to evaluate the impact of various ingredients on the composition, physicochemical, organoleptic and storage characteristics of the milk chocolates and thereby to suggest a simple process for manufacture of acceptable milk chocolates with a small but reasonable shelf life. Raw groundnut kernels were roasted in tray in an air-oven maintained at 150 + 10 °C for 15 min. After this treatment, the skin and hearts were removed manually and the skin free and heart free cotyledons were cut into small pieces manually. For the preparation of golden syrup, concentrated hydrochloric acid was added at the rate of 1 per cent to a sugar solution (67° brix) and the solution was heated to 85°C for 40 min. After cooling the pH of the solution was adjusted to 7.00 by using sodium bicabonate. Milk chocolates were prepared by using buffalo milk as base and other ingredients such as roasted groundnuts/ sugar, golden syrup/ table butter/ cocoa powder/ glycerol mono-stearate/ shellac and tri-sodium orthophosphates were incorporated in the formulation of four types of recipe to manufacture four types of milk chocolates namely CT-1/ CT-2/ CT-3 and CT-4. The' milk chocolate type/ CT-1, contained 15 g table butter and 75 g roasted groundnuts per batch. Type CT-2 contained 25 g table butter and 50 g roasted groundnuts whereas CT-3 contained 20 g table butter and 60 g roasted groundnuts. The recipe of CT-4 consisted of 10 g table butter and 100 g roasted groundnuts. In addition to these two ingredients, all the four types of milk chocolates consisted of equal amount of rest of the ingredients per batch. Milk chocolates were manufactured by adding various ingredients to the buffalo milk taken in a pan. The contents of the pan was stirred at a temperature 90-95°C till a viscous mass was obtained. This viscous mass was transferred to a tray to harden and after hardening/ it was cut into small pieces and wrapped in aluminium foil. These small pieces of milk chocolates were transferred to plastic boxes. Four such trials were conducted and the product were stored at 27-30°C as well as 4-8°C under a domestic refrigerator. The major ingredients were analyzed for their proximate chemical composition and the milk chocolates were analysed for their compositional, rheological properties/ organoleptic characteristics and chemical changes occurring during storage for a period of 60 days. The roasted groundnuts contained 45.88 per cent oil/ 26.21 per cent protein, 2.90 per cent moisture, 2.10 per cent ash and 22.91 per cent total carbohydrates. The cocoa-powder used possessed 14.58 per cent fat and 6.00 per cent moisture. The table butter was found to contain 83.70 per cent fat and 16.73 per cent moisture. The golden syrup was found to contain 60 per cent sucrose and total solids 69°brix. The yield of the four types of milk chocolates CT-1, CT-2, CT-3 and CT-4 were 384.66, 371.05, 371.16 and 388.55 g per kg of the ingredients used. The chemical composition of the four types of milk chocolates showed that CT-1, CT-2, CT-3 and CT-4 on an average contained moisture 9.63, 9.84, 6.92 and 7.49 per cent; total fat 31.06, 31.84, 29.87 and 32.69 per cent; total protein 11.72, 11.38, 11.84 and 12.54 per cent; sugar (sucrose) 48.18, 49.56, 52.76 and 49.93 per cent; total ash 0.88, 0.99, 0.98 and 0.96 per cent; sodium 179.28, 177.39, 196.10 and 147.81 mg per 100 g; calorific value 4295.36, 4117.18, 4099.21 and 4327.13 calories per g and soluble matter 66.90, 60.72, 61.64 and 56.37 per cent respectively. The rheological characteristics of CT-1, CT-2, CT-3 and CT-4 were hardness, 15.82, 15.52, 22.47 and 17.76 kg; brittleness, 4.11, 4.80, 5.02 and 2.91 kg; cohesiveness, 0.030, 0.038, 0.029 and 0.034; springiness, 1.62, 2.06, 1.75 and 1.87 mni; gumminess/ 47.12, 60.73, 65.81 and 55.45 kg and chewiness, Q.11, 1.41, 1.13 and 1.05 kg mm respectively. The physico-cheroical changes namely status of moisture, pH, free fatty acids and peroxide value were evaluated in fresh and during storage at various intervals for a period of 60 days at two different storage conditions i.e., at 27-30°C and at 4-8°C under a domestic refrigerator. The initial levels of moisture in CT-1, CT-2, CT-3 and CT-4 milk chocolates was 7.85, 8.02, 5.63 and 6.09 per cent respectively which on 60 days storage changed to 5.97, 6.43, 7.07 and 7.33 per cent respectively. The milk chocolates stored at 4-8°C for a period of 60 days showed the moisture content to be 5.87, 7.55, 5.60 and 5.91 for CT-1, CT-2, CT-3 and CT-4 respectively. The pH values of CT-1, CT-2, CT-3 and CT-4 milk chocolates were 7.02, 6.87, 6.79 and 6.78 initially which on storage at 27-30°C dropped to 6.86, 6.75, 6.76 and 6.76 respectively while those stored at 4-8°C increased to 7.09, 6.97, 6.87 and 6.96 respectively. The free fatty acids content (as per cent oleic acid) of CT-1, CT-2, CT-3 and CT-4 milk chocolates were 0.08, 0.08, 0.10 and 0.09 initially which increased to 0.16, 0.17, 0.14 and 0.18 on 60 days storage at 27-30°C while those stored at 4-8°C increased to 0.11, 0.09, 0.11 and 0.10 respectively after a storage period of 60 days. The peroxide content (milliequivalent per kg of sample) was initially 1.50, 1.00, 3.50 and 3.00 which increased to 9.50, 2.50, 6.00 and 5.00 for milk chocolates stored at 27-30°C and 5.50, 5.50, 6.50 and 6.00 for milk chocolates stored at 4-8 C after a storage period of 60 days for CT-1, CT-2, CT-3 and CT-4 respectively. The sensory quality of different types of milk chocolates wno evaluated for colour, flavour and texture as affected due to storage. The effect of treatment as well as effect of storage period on colour score was found to be non-significant (P <0.05) under both conditions of storage. The flavour score was decreased but the effect of treatment and storage period were nonsignificant (P < 0.05) under both storage conditions. Milk chocolate types, CT-2 and CT-4, were unacceptable after a storage period of 60 days at 27-30°C from flavour point of view. The effect of treatment and storage period on texture score was nonsignificant (P <0.05) under both storage conditions. Milk chocolates type, CT-2, and CT-3, was unacceptable with respect to texture after a storage period of 60 days at 27-30°C.
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    ThesisItemOpen Access
    COMPARATIVE APPRAISAL OF PHYSICO-CHEMICAL AND SENSORY CHARACTERISTICS OF KALAKAND AND ITS ANALOGUES PREPARED FROM ADMIXTURES OF BUFFALO MILK, PARTIALLY DEOILED GROUNDNUT FLOUR AND ROASTED GROUNDNUT KERNELS
    (AAU, Anand, 1997) SOM, SUMITA; Singh, Sukhminder
    Two types of kalakands and three types of kalakand analogues were prepared from the standardized (6 per cent) buffalo milk and its blend with groundnut solids, respectively, using citric acid as the acidulant and its blend with groundnut. Kalakand prepared by the NDRI procedure was used as the control (Tc). Kalakand type T1 was prepared using sucrose hydrolysate (made from a mixture of 180 g cane sugar, 60 ml water and 1.5 g citric acid as a catalyst) as a replacement of cane sugar in a similar manner as that of Tc. Kalakand analogues were prepared by 50 per cent substitution of the milk solids by an admixture of RPDGF-RGK (25 : 25, w/w). The analogues were designated as : T2 (prepared from 1.5 L standardized buffalo milk, 190 g groundnut ingredients consisting of equal amounts of RPDGF and RGK, 2 g citric acid and 240 g cane sugar), T3 (same as T2 but cane sugar was substituted by sucrose hydrolysate made by inversion of 240g cane sugar dissolved in 90 ml water using 2g citric acid as a catalyst) and T4 (same as T2 but contained 1.5 g sodium chloride and 0.2g disodium hydrogen phosphate as the sah mixture). The various steps involved in the processing of raw groundnut kernels into RGK were : roasting of raw kernels, deskinning, dehearting and crushing, whereas for RPDGF preparation the steps were : soaking of kernels in water, precooking, deskinning, dehearting, pressure cooking, oven drying, partial deoiling, sieve cooking of meal, grinding, sieving of flour and finally mild roasting. Sucrose hydrolysate (54.4 per cent invert sugar) as a substitute for cane sugar was prepared by heating a solution of cane sugar in water (3:1. w/v) in the presence of citric acid (0.625 per cent) over a boiling waterbath for 15 min. The preparation of kalakand Tc by the NDRI procedure of open pan heat desiccation involved boiling of milk, addition of citric acid, continuous stirring and heating until milk desiccated to l/3rd of its original volume, addition of cane sugar and mixing, desiccating to semi-solid consistency, cooling to room temperature and cutting into square pieces. The steps involved in the preparation of kalakand T1 were the same as for kalakand Tc except that sucrose hydrolysate instead of cane sugar was added to the boiled milk and then desiccated to prepare the product. The preparation of kalakand analogues involved essentially the same steps as for Tc with the following modifications. For the preparation of all the analogues RPDGF was admixed at the semi-solid consistency stage and saffron flavour was added on cooling to room temperature. T3 contained sucrose hydrolysate in place of cane sugar as in T2 and T4. In the preparation of T4 a salt mixture was added to the milk before boiling. Raw groundnut kernels, RGK and RPDGF were analysed for their proximate chemical composition, the average values of four replicates showed 4.52, 1.68 and 2.95 per cent moisture; 26.41, 28.28 and 50.29 per cent total protein; 47.02, 49.71 and 25.89 per cent fat; 2.60, 2.43 and 3.40 per cent ash; and 19.44, 17.90 and 18.05 per cent total carbohydrates, respectively. Aflatoxin content was 25.0 to 35.0 and 12.5 to 17.5 ppb in raw groundnut kernels and RPDGF, respectively. The standardized (6 per cent fat) buffalo miUc had on an average 15.84 per cent total solids, 4.22 per cent protein, 4.83 per cent lactose, 0.84 per cent ash, 0.17 per cent acidity (as lactic acid), 0.24 per cent citric acid and 0.15 per cent calcium. The average values of four replicates of the products showed that the moisture, protein, fat, lactose, sucrose, ash, acidity (lactic acid), citric acid, calcium and free fat, respectively, were 20.40, 16.28, 23.10, 17.07, 20.00, 2.86, 0.62, 2.21, 0.45 and 17.67 per cent for T,; 20.77, 16.20, 23.10, 27.78(total reducing sugars), 8.33, 2.82, 0.62, 2.19, 0.46 and 35.85 per cent for T1 ; 26.52, 18.24, 12.07, 6.95, 33.55, 2.33, 0.41, 0.75,0.33 and 5.99 per cent for T2; 28.65, 18.15, 12.07, 21.90 (total reducing sugars), 23.74, 2.46, 0.42, 0.74, 0.32 and 8.45 per cent for T3; and 25.54,18.03 12.07, 6.98, 32.96, 2.48,0.42, 0.75, 0.33 and 5.72 per cent for T4. The average yields (g per litre of milk) of Tc, T1, T2, T3 and T4 were 258,260, 579, 626 and 574, respectively. The chemical changes in RGK and RPDGF during storage at room temperature (25° to 32°C) were evaluated at intervals of 2 days for a period of 4 days. Both RGK and RPDGF showed a decrease in moisture as well as in soluble-N with a concomitant increase in FFA, PeOV and HMF with the period of storage. Similar storage studies were done for kalakand and its analogues. The moisture content and soluble-N of all the kalakands and analogues decreased significantly (P < 0.05) throughout the storage period. The initial FFA levels were identical in Tc, T1, and T2 but that in T3 and T4 differed significantly (P < 0.05). With period of storage, FFA levels was more or less constant in Tc, T1, and T4 but sUghtly decreased in T2 and T3 on the 2nd day, however, FFA increased marginally on the 4th day and increased appreciably on the 6th day in all the samples. The initial PeOV were 3 to 4 times higher in the analogues than the kalakands and on the 2nd day of storage the PeOV decreased sUghtly in the kalakand but substantially in the analogues. On the 4th and 6th day, PeOV increased regularly in kalakand and analogues excepting T3 in which case a decrease in PeOV on the 4th day was observed. The initial HMF content was higher in the analogues than the kalakand and a significant (P < 0.05) increase was observed with the storage period. The sensory qualities of kalakand and its analogues were compared with that of the control. The kalakands (Tc and T1) showed significantly (P<0.05) higher scores for flavour, and body and texture than that of the analogues when freshly prepared. The highest average colour and appearance scores was found for Tc (7.03) closely followed by T4 (6.53). However, the highest average overall acceptability score was for T4 (7.22) followed by Tc (7.18). The statistical analysis showed that the differences in the overall acceptability were nonsignificant. The results of sensory scores of the overall acceptability at different periods of storage revealed significantly higher score for the control (7.00) and T1 (7.02) than the analogues on the 2nd day. However, the mould growth was observed on the 4th day in the analogues but not on the kalakands (Tc and T1). The kalakands Tc and T1 had an overall acceptability scores of 6.61 and 6.76 respectively on the 4th day of storage, and thus were considered acceptable on the 9-point hedonic scale but deteriorated on the 6th day due to the appearance of mould.
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    ThesisItemOpen Access
    EFFECT OF BOVINE MILK K-CASEIN GENETIC POLYMORPHS ON CURD CHARACTERISTICS DURING CHEDDAR CHEESEMAKING
    (AAU, Anand, 1997) Patil, Madhav Raghunathrao; Boghra, V. R.
    For the study, the cows from triple cross (Holstein Friesian x Jersey x Kankrej) and Jersey breeds were previously typed for their K-casein genotypes by performing polyacrylamide-urea vertical slab gel electrophoresis. In triple cross cows, the K-casein genotypes resolved were AB and AA, whereas in Jersey cows, these genotypes were BB and AB. Eight mid-lactating cows from each breed were selected for collection of milk. Among 8 cows of triple cross breed, 4 had K-casein AB genotype and 4 had K-casein AA genotype. Similarly, among 8 Jersey cows, 4 had K-casein BB genotype and 4 had K-casein AB genotype. Pooled milk from triple cross and Jersey cows served as control for respective breed groups. The milk was analysed for its proximate chemical composition and coagulation properties (RCT and curd firmness). The Cheddar cheese was prepared from milks of each K-casein genotype and respective control of both the breeds under identical practical conditions by using standard method (Davis, 1976). The compositional analysis showed that milk from triple cross cows having K-casein AB, K-casein AA genotypes and control contained on an average milk fat, 5.46, 4.98 and 4.40 per cent; milk protein, 3.74, 3.42 and 3.27 per cent; casein, 3.01, 2.75 and 2.61 per cent; lactose, 4.53, 4.67 and 4.72 per cent and ash, 0.80, 0.75 and 0.73 per cent, respectively. On subjecting data for statistical analysis, milk fat only showed significant difference (P<0.05). Likewise for the K-casein BB, K-casein AB and control milks from Jersey breed, the average values were 5.05, 4.92 and 4.38 per cent for milk fat; 3.73, 3.54 and 3.25 per cent for protein; 3.02,2.91 and 2.59 per cent for casein; 4.37, 4.40 and 4.44 per cent for lactose and 0.75, 0.73 and 0.72 per cent for ash content, respectively. Statistical analysis showed no significant difference for any of these constituents. The K-casein AB milk showed relatively higher titratable acidity (0.153 % LA) than K-casein AA (0.143 % LA) and control (0.140 % LA) milks from triple cross cows. A similar trend was also observed with Jersey milk having different genotypes. The milks from triple cross cows having genotypes K-casein AB contained higher calcium, phosphorus and lower citrate contents than K-casein A A and control milks, whereas in Jersey cows K-casein BB and K-casein AB genotypes contained higher calcium, phosphorus and lower citrate contents than control. The coagulation properties of milk from triple cross breed having K-cascin AB variant, K-casein AA variant and control were : rennet clotting time (sec), 39.92, 52.12 and 96.72 and curd firmness (mm), 481.67, 497.00 and 505.11 respectively, whereas these values were, 30.95, 41.03 and 77.85 (RCT, min) and 471.83, 490.50 and 505.83 (curd Firmness, mm) for K-casein BB variant, K-casein AB variant and control milk respectively from Jersey breed. Amongst the triple cross breed, the K-casein AB milk coagulated faster with rennet than K-casein AA and control milks. In Jersey, K-casein BB and AB milks showed shorter RCT than control milk. In both the breeds, the K-cascin genotypes showed statistical significant difference ( P<0.05) for milk coagulation properties. The mean values for recoveries of constituents in cheese made from milk of triple cross breed were; fat, 91.56, 86.88 and 85.56 per cent; protein, 78.06, 76.37 and 70.91 per cent and total solids, 54.42, 52.63 and 48.03 per cent for K-casein AB, K-casein AA and control milks respectively. Statistical analysis of data showed significant difference (P<0.05) only in total solids contents. In case of Jersey breed, these values for K-casein BB, K-casein AB and control cheeses were : fat, 84.29, 83.85 and 83.09 per cent; protein, 72.78, 68.91 and 68.78 per cent and total solids, 51.33, 50.17 and 48.23 percent, respectively. The average values of wet yield, actual yield and actual yield adjusted to 37 % moisture were 13.09, 10.95 and 11.85 per cent, respectively for K-casein AB milk, which were relatively higher than the values (12.80, 10.30 and 11.45 per cent, respectively) for K-casein AA milk and (11.86, 9.29 and 10.30 per cent, respectively) for control milk from triple cross breed. While these values were 12.30, 10.64 and 11.19 per cent, respectively for K-casein BB milk which was relatively higher than the values, 12.15, 10.08 and 10.99 per cent, respectively for K-casein AB milk and 11.10, 9.23 and 9.77 per cent, respectively for control milk from Jersey breed. Compositional analysis of cheese made from milk having K-casein AB, K-casein AA and control milks from triple cross cows showed on an average fat, 34.00, 36.00 and 35.83 per cent; Protein, 26.42, 25.40 and 24.98 per cent; total solids, 65.86, 66.85 and 66.62 per cent and ash, 3.47, 3.57 and 3.49 per cent, respectively, whereas the average values of these constituents in cheese made from K-casein BB, K-casein AB and control milks of Jersey breed were, fat, 33.83, 35.50 and 34.83 per cent; protein, 25.49, 24.26 and 24.23 per cent; total solids, 64.81, 65.57 and 64.94 per cent and ash, 3.78, 3.75 and 3.78 per cent, respectively. In both the breeds only protein content showed statistically significant difference (P<0.05). The whey samples of cheeses made from milks having K-casein AB, K-casein AA genotypes and control represented the fat contents of 0.33, 0.45 and 0.47 per cent; protein contents of 0.81, 0.87 and 0.89 per cent; and total solids contents of 6.75, 7.03 and 7.01 percent respectively from triple cross cows. Likewise these values were for 0.53, 0.57 and 0.58 per cent for fat; 0.92, 0.95 and 0.96 per cent for protein and 7.00, 7.02 and 7.07 per cent total solids in whey samples of cheeses prepared from milks having K-casein BB, K-casein AB genotypes and control milks respectively from Jersey cows, hi the triple cross cows, genetic variants of K-casein affected significantly the losses of total solids in whey. On the other hand in Jersey breed, there was no significant difference in the total solids contents of the different whey systems.
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    ThesisItemOpen Access
    EXTRACTION OF ANTIOXYGENIC PRINCIPLES FROM RAGI (Eleusine coracana) AND THEIR EFFECT ON OXIDATIVE STABILITY OF GHEE
    (AAU, Anand, 2002) MEHTA, BHAVBHUTI MANOJBHAI; Beghra, V. R.
    A study was carried out to elucidate the effect of addition of antioxidant principles of Ragi (Eleusine coracana Linn) via methanol pfe-extract on oxidative stability of ghee. The Dehusked Ragi powder (DRP) contained on an average 10.05 per cent moisture, 2.00 per cent lipid, 6.10 per cent protein, 79.65 per cent carbohydrates, 2.20 per cent ash. It contained on dry matter 2.55. per cent total phenolics and 0.17 per cent phospholipids compounds. Ghee samples were procured from a commercial dairy plant, Vidya Dairy, Gujarat Agricultural University, Anand. Methanol extract of DRP was evaluated for their effectiveness against oxidative deterioration of ghee. In all trials, the samples were analysed for peroxide value after an interval of 48 h at 80 ± 2 °C. In order to evaluate the relative effectiveness of the additives at different levels the induction period (hours required to reach a peroxide value of 5 meq. of peroxide 'oxygen per kg) of ghee samples were deteraiined. To understand further the effect of such additions, the antioxidant indexes (protection factors) were calculated as the ratio of the induction period of the treated sample to the induction period of the control. The methanol pre-extract of DRP added to ghee at the rate of 0.0 (To, Control), 0.1 (Ti), 0.25 (Ta) and 0.5 (T3) per cent (v/v) levels. For comparison, addition of butylated hydroxyl anisole (BHA) was added at the legally permitted rate of 0.02 per cent (T4). The samples were kept at 40 ±2 °C for 30 min, then temperature was raised to 50 ±2 °C for half an hour and then temperature was raised upto 120 °C and allow to cool at 60 °C. Ghee samples were filtered through four layers of muslin cloth and immediately transferred to an oven maintained at 80 ± 2 °C for accelerated storage studies. In all the trials, ghee samples were analysed for different constituents like moisture, free fatty acids, phospholipids, water extractable phenolics and methanol extractable phenolics. The average moisture content of ghee sample varied from 0.185 to 0.197 per cent and the initial free fetty acid (as per cent oleic acid) varied from 0.518 to 0.522 per cent. The phospholipids in the treated ghee samples varied on an average from 3.99to 12.14 mg/100 g. The water extractable phenolics ranged on an average form 0.32 to 2.78 mg/lOOg of ghee, the order being 2.78 (T3) > 1.25 (T2) > 0.52 (T1) >0.36 (T4) >0.32 (To) mg/lOOg of ghee. The methanol extractable phenolics varied on an average from 1.5 to 9.0 mg/lOOg, the order being 9.0 (T3) > 4.7 (T2) > 1.8 (T1) >1.5(T4) mg/lOOg of ghee. The overall induction periods of different treatments were found to be in the sequence of 278.7 (T3)> 195.5 (T2)> 191.5 (T4)> 152.5 (Ti) > 103.7 (To) hours. The antioxygenic indexes (protection factor) were found to be in the order of 2.75(T3) > 1.93 (T2)> 1.89 (T4)>1.47 (T1). From the resuUs of this study, it was concluded that the antioxygenic compounds of Ragi can be extracted in methanol and enhance the oxidative stability of ghee. Addition of methanol pre-extract of DRP at the level of 0.5 per cent (v/v) was found to be more effective than the addition of BHA at the level of 0.02 per cent of ghee. The polyphenolics as well as phospholipids compounds present in the ragi appeared to be the main contributory factors in enhancing the oxidative stability to ghee.
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    ThesisItemOpen Access
    STANDARDIZING CONDITIONS FOR PILOT SCALE PRODUCTION AND STORAGE OF WHOLE BUFFALO MILK DAHI USING STREPTOCOCCUS THERMOPHILUS : SOME CHEMICAL ASPECTS
    (AAU, Anand, 1990) Sharma, Prabhat Kumar; Singh, Sukhminder
    Nine different types of dahi were prepared from whole buffalo milk standardized to 4,5 per cent fat but having three different concentrations of total solids namely 15(TS-l), 18(TS-2) and 21(TS-3) percent.Performance of three strains of Streptococcus thermophilus namely MD2(SC-l), MD8(SC-2) and D3(SC-3) was evaluated using each of the standardized milk adjusted to predetermined total solids level for its dahi making qualities. Condensed Buffalo skim milk (1:3 concentration) was used for the standardization of total solids of raw whole buffalo milk. The steps followed for the dahi making were t Standardization of milk to predetermined fat and total solids level, preheating to 60°C, homogenization in single stage homogenizer (100 kg/cm2 pressure), preheating at 85°C for 10 min, cooling to 40°C, adding cultures at 2 per cent rate, filling in polystyrene cups with lid on, inctabating at 40 + 1°C till 0.75 per cent acidity and finally keeping in the refrigerator (6 ± 1°C) for about 12 h. This was considered the 0 h storage. For assessing the chemical changes in dahi during storage at refrigeration temperature (6 + 1°C) the samples were drawn at intervals of 6 days upto total of 18 days, while during storage at room temperature (37 + 1°C) the samples were drawn at intervals of 12 h upto total of 48 h . All the treatments were replicated four times. The mean values of the chemical constituents of milk and dahi of TS-1, TS-2 and TS-3 treatments showed significant (P<0.05) differences in the levels of total solids , lactose, protein and pi but non significant differences in fat and acidity . Effect due to the use of the type of culture, namely, SC-1, SC-2 and SC-3 was non significant on the t o t a l solids, fat, protein, lactose, acidity and pH values of dahi manufactured from milk of each level of s o l i d s . The three types of starter cultures had significant (P < 0.05) effect on total lactic acid, while non significant effect on citric acid, orotic acid and free fatty acids of dahi. The order of cultxires in the increasing content of lactic acid, orotic acid and free fatty acids in each case was: SC-3 > SC-2 > SC-1, while, the order of cultures in the increasing content of citric acid was: SC-2 > SC-3 > SC-l. The mean values (ppm) of diacetyl and acetaldehyde were: 0.625 and 4.707; 0.773 and 5.458; and 0.882 and 6.817 in TS-1, TS-2 and TS-3 treatments, respectively. The overall increasing order of diacetyl production by different starter cultures was t SC-1>SC-2>SC-3. Whereas the increasing order of acetaldehyde production was SC-1> SC-3 > SC-2 in all the treatments of total solids of dahi. The diacetyl production was influenced significantly (P SC-2 > SC-l as the levels of nonprotein nitrogen and tyrosine value were higher in the order of the cultures, irrespective of the treatment of dahi. The statistical analysis of levels of titratable acidity, free fatty acids, diacetyl, tyrosine value and total lactic acid of dahi during room temperature (37 + 1°C) storage revealed significant (P<0.05) differences in titratable acidities, free fatty acids, diacetyl, tyrosine value and total lactic acid. The maximum levels of titratable acidity, free fatty acids and tyrosine valxoe were observed at 48 h while the maximum levels of diacetyl and total lactic acid were observed at 24 h of storage. During storage at refrigeration temperature, the maximum levels of titratable acidity and total lactic acid were on the 12 d of storage; maximum levels of free fatty acids and tyrosine value were on the 18 d of storage, while the maximum level of diacetyl was on 0 d of storage. Different periods of storage showed significant (P< 0.05) differences in titratable acidity, free fatty acids, diacetyl and tyrosine value but nonsignificant in total lactic acid. Polyacrylamide gel electrophoresis of casein isolated from dahi revealed k-casein was degraded during 0 h of storage and both k- and aseins were degraded during 24 h of storage of dahi at room temperature. Paper chromatographic analysis of carbohydrates revealed the presence of glucose, galactose and lactose during storage of dahi for 24 h at room temperature. The concentration of glucose was lower than galactose at 24 h storage of dahi indicating that glucose is preferentially utilized by the starter cultures. The sensory evaluation of dahi revealed that the dahi of best quality can be prepared from buffalo milk of TS-l treatment (15 per cent total solids and 4,5 per cent fat) using MDQ(SC-2) strain of Streptococcus thermophilus as the starter and with no storage either at refrigeration or room temperature, Dahi from milk of TS-l treatment using Streptococcus thermophilus MD8 as the starter culture had the following average chemical composition : 15.17 per cent total solids; 4.53 per cent fat; 5.23 per cent protein; 3,66 per cent lactose; 1.05 per cent acidity; 4.57 pH; 0.58 per cent total lactic acid; 131.00 (mg/100g) citric acid; 0.90 µeq/g free fatty acids; 17.17µg/g orotic acid; 0.63 ppm diacetyl; 4.52 ppm acetaldehyde and 96.50 (µg/g) tyrosine value. The nitrogen distribution (per cent) in different fractions of dahi were 0.82, total nitrogen; 0.06, non-casein nitrogen;0.03 proteose-peptone nitrogen and 0.03 nonprotein nitrogen. Thus standardized buffalo milk of TS-l treatment, that is , milk having mean values of 15.33 per cent total solids, 4.65 per cent fat, 4.86 per cent protein, 5.70 per cent lactose, 0.19 per cent titratable acidity and 6.84 pH, is recommended for the commercial production of dahi of best quality under the standardized conditions as described and using 2 per cent of Streptococcus thennophilus MD8 as the starter culture.