Milk Blend Research Articles

Instrumental Textural Profile Analysis of Soy Fortified Pressed Chilled Acid Coagulated Curd (Paneer)

Studies were conducted to observe the effect of varying fat content in milk (0–6%) and varying proportion of soy milk (7.5°B, 0–40%) in the blend on the textural properties of Soy Fortified Paneer (SFP). Instrumental Texture Analyzer of Stable Micro System was used to measure the texture of paneer containing varying level of fat and soy solids for texturel profile analysis (TPA). Texture profile data, thus obtained, were used to develop regression models between fat content in milk and proportion of soy milk in blend with that of the dependent variable hardness, cohesiveness, chewiness, springiness and adhesiveness. The high correlation coefficients of each developed model confirmed its suitability in representing experimental data. Based on to these models SFP samples prepared using a blend (15:85 v/v) of soy milk (7.5°B) and buffalo milk (3.12%) was found to be suitable for producing textural characteristics similar to that of control paneer sample.

Development of Whey Beverage with Antagonistic Characteristics and Probiotics

A process was standardized to develop whey beverages in combinations with and without skim milk, using selected strains of Lactobacillus acidophilus NCDC-15, L. casei NCDC-12, and L. casei RTS, which have antagonistic properties, and bile salt tolerance. L. acidophilus NCDC-15 in combination with L. casei NCDC-12 produced a highly acceptable beverage which had antagonistic properties against food borne pathogens (Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Staphylococcus aureus) and showed maximum tolerance at pH 4.0 and in presence of 0.5 per cent bile salt. The growth characteristics of selected strain were studied in 50:50 and 100:00 blends of whey and skim milk at 37 ± 1°C following 16 h of incubation. L acidophilus NCDC-15 in combination with L. casei NCDC-12 strains produced highly rated acceptable beverage as determined by a sensory panel and also was best in terms of lowest pH, maximum titratable acidity, rate of acid production, percent soluble nitrogen, and acetaldehyde production.

FUZZY MULTIATTRIBUTE DECISION MAKING APPROACH FOR DEVELOPMENT AND COMPARISON OF SOY FORTIFIED PANEER

ABSTRACTSoyfortified paneer (SFP) samples prepared from blends containing different proportions of buffalo milk of varying fat content and soy milk (7.5 °B) were evaluated organoleptically for assessing the quality attributes like body and texture, flavor and taste, color and appearance and the overall acceptability. Sensory data were analyzed using fuzzy logic approach, which addresses the problem of data classification in a unified qualitative and quantitative manner. Results of the study indicated that the fuzzy multiattribute decision making approach provide an adequate and reliable system for product formulation and comparison, based on sensory data. The developed fuzzy mathematical model performed remarkably well in the evaluation and ranking of various SFP samples. The SFP sample made from blend of buffalo milk (4.5% fat) and soy milk (7.5 °B) in the proportion of 90:10 was found to be the most acceptable one for different classes of consumers irrespective of their preferences for a particular sensory quality attribute.

The use of continuous ricotta processing to reduce ingredient cost in ‘further processed’ cheese products

Abstract The continuous ricotta process developed at Agriculture and Agri-Food Canada (AAFC) has now been commercialized and is capable of producing a wide range of protein-containing ingredients originating from either milk or whey or from combinations of milk and whey, blended in any proportion. Wide ranges of protein-containing ingredients have been prepared to date. These include whole-milk ricotta, whey-based ricotta, ricotta from blends of milk and whey (e.g., 75% whey and 25% milk) with the potential to produce casein, Paneer and Queso Blanco. The protein-containing ingredients can be tailored to the desired fat-in-dry-matter requirements depending on the end use. Moisture is the first limiting factor in product application. Usage in processed cheese food/spreads and cream cheese type products is restricted to about 25 to 32%. At these levels of substitution, no functional abnormalities have been observed. Ricotta is essentially a wet coprecipitate that has a broad range of product application and has the advantage of not aggregating to form a gritty texture in products prepared by heating under acidic conditions, e.g., cheese spreads and cheese foods. The protein content of ricotta cheese ranges from about 44 to 70% on a dry basis. Whole milk ricotta has a value of about 10.16 ($CA) kg−1 of protein (dry basis) while cheese prepared from 90% ultrafiltered whey (4 : 1) and 10% milk is worth approximately CA$ 5.64 kg−1 of protein ($1 CA equivalent to $0.67 US, February 2000). Ricotta can compete with other dairy ingredients on a protein basis and should be given consideration when doing least-cost formulations.

Thermal stability of skim milk/whey protein solution blends

Dried protein fractions consisting predominantly of α-lactalbumin, β-lactoglobulin or a whey protein concentrate (WPC) were dissolved in skim milk ultrafiltration permeate at 3.44% (w/w) protein. Each solution, denoted as α-FS, β-FS or WPCS, was blended with skim milk at ratios of 100/0–60/40 (g skim milk g −1 whey protein solution), to increase the ratio of whey to casein protein without changing the concentration of total protein. The blends were adjusted to pH values in the range 6.6–7.1 and heat stability determined by measuring the heat coagulation time at 140°C. At initial pH 6.6–6.7, blends of skim milk and α-FS were slightly more heat stable than normal skim milk; gel electrophoresis indicated that thermal association between α-la and casein may have augmented heat stability. From pH 6.8–7.1, the blends were considerably less heat stable than normal skim milk, possibly due to the formation of soluble complexes between α-la and κ-casein and accompanying heat-sensitive, κ-casein-depleted casein micelles. In most cases, enrichment of skim milk with β-lg, by blending with β-FS or WPCS, caused a drastic reduction in heat stability; this was attributed to the low heat stability of β-lg. An exception to this trend was the high heat stability of a 70/30 blend of skim milk and β-FS or skim milk and WPCS; electrophoresis indicated that the heat stable entity was a complex between β-lg and casein.

Chemical and sensory evaluation of vegetable milks from African yam bean Sphenostylis stenocarpa (Hochst ex A Rich) Harms and maize (Zea mays L.).

Vegetable milks were developed from fermented and unfermented African yam bean (AYB) flours and their maize blends. AYB was cleaned, dehulled, milled and fermented for 24 hours by the natural microflora present in the legume flour. Maize was fermented for 48 hours. A ratio of 70:30 (protein basis) of AYB: maize was used to formulate the blends. Vegetable milks were prepared from the AYB flours and their maize blends. Standard assay techniques were used to evaluate the milks for proximate, mineral, ascorbate and antinutrient composition. The protein contents of the milks (1.47-2.06 percent) was comparable to soymilk (2.04 percent) and bambara groundnut milk (2.00 percent). The milks contained appreciable quantities of carbohydrate and minerals tested. The milk blends had traces of ascorbate and contained higher phosphorus than the milks from the AYB flours. The fermented milk blend had higher protein, ash and sugar levels and lower phytate and stachyose levels compared to non-fermented blend. Raffinose was reduced to trace levels in the fermented milks. The milks were appetizing. The fermented milk blend was more acceptable than others and was preferred in terms of flavor and color. It had greater advantages over the other vegetable milks evaluated in terms of zinc, phosphorus and stachyose levels.

Influence of κ-casein and β-lactoglobulin genetic variants on the heat stability of milk

SUMMARYHeat coagulation time-pH curves at 140°C were obtained for 43 blended skim milk samples from Holstein cows to determine the effects of genetic variants of κ-casein and β-lactoglobulin on milk heat stability. The blended milk samples were similar in terms of protein content and milk salts, but were genotypically different for κ-casein (AA, AB) and β-lactoglobulin (AA, AB, BB). Type A curves were obtained for all milks. Maximum heat stability was affected by the κ-casein genotype (AB > AA, P < 0·01) but the influence of the β-lactoglobulin genotype was only significant when the κ-casein AA genotype was present (β-lactoglobulin AA > BB, P < 0·0001). Minimum heat stability was significantly higher (P < 0·0001) for milk genotyped κ-casein AB:β-lactoglobulin BB. The effects of milk genotyped κ-casein BB on maximum and minimum heat stability were determined by analysing individual milks: κ-casein BB:β-lactoglobulin AB (n=8) and reconstituted milks: κ-casein BB:β-lactoglobulin AA, AB and BB (n = 17). Type B curves were obtained on three occasions for individual κ-casein BB:β-lactoglobulin AB milk and on five occasions in the case of reconstituted milks with κ-casein BB:β-lactoglobulin AA, AB and BB. This suggests a relationship between the type B curve and the κ-casein B genetic variant. Comparison of the mean values of heat stability at the pH of maximum heat stability of each individual and reconstituted milk genotype suggested that the best genotype for κ-casein in terms of heat stability was BB.

Changes in organoleptic quality during ripening of cheese made from cows and soya milk blends, using microbial rennet

The organoleptic characteristics of cheese made from various cows and soya milk blends are directly related to the proportion of soya milk in the blend. The sensory attributes of cheese samples made from cows milk, using calf rennet, did not differ significantly from those of cows milk cheese made with microbial rennet. Soya cheese samples were prepared from different cows and soya milk blends and were evaluated for their sensory properties. Flavour and body texture scores of soya cheese decreased with increase in proportion of soya milk in the blend, whereas the color score increased with increase in the proportion of soya milk in the blend. However, during ripening, the sample made from a blend containing even 5% soya milk differed significantly from the control in respect of flavour, as well as in body and texture.

Microfiltration, Ultrafiltration, and Centrifugation Separation and Sterilization Processes for Improving Milk and Cheese Quality

Separation and sterilization processes involving centrifugation, ultrafiltration, and microfiltration are reviewed as to characteristics, tentative performance, and potential advantages. These processes require one or more separating means to remove skim milk or permeate from whole milk, followed by heating the resulting creams or retentates to 120°C and then blending the fat-free material with the fat component. The blend is thereafter homogenized as required, pasteurized, cooled, and used as fluid milk or for manufacture of cheese and other dairy products.Trials on milk blends produced by separation and sterilization principles using centrifugation, ultrafiltration, or microfiltration show increased shelf-life at chill temperatures for all blends. Such whole milk retained good quality compared with quality of controls for many days, the number being influenced directly by storage at 3.3 to 8.0°C. Cheddar and Emmental cheese of high quality were produced by the separation and sterilization processes.

EFFECT OF PAPAYA PULP ADDITION ON THE GROWTH OF LACTOBACILLUS ACIDOPHILUS

ABSTRACTEffect of papaya pulp addition to skim milk on the growth characteristics of five strains of Lactobacillus acidophilus was investigated. All the strains tested exhibited higher viable counts, shorter generation time, increased acid production, greater sugar utilization and fall in pH upon addition of papaya pulp. The generation time, acid production, sugar utilization and pH values at the end of 18 h fermentation of skim milk by different strains were 150–200 min, 0.29–1.73%, 0.39–2.22 g/100 mL and 3.85–6.10, respectively. The corresponding values for 10% papaya pulp added skim milk blend were 120–143 min, 0.51–1.84%, 0.70–2.79 g/100 mL and 3.70–5.10, respectively. Organoleptic evaluation revealed that papaya pulp addition imparted firmness to the coagulum and thus enhanced the acceptability of the product by eliminating the problem of wheying‐off and improved flavor.

Development of a Continuous Process for the Production of Ricotta Cheese

A process was developed for the continuous production of Ricotta cheese. The process consists of multistep heating to 92°C, whey protein denaturation in a 10-min holding tube, acid injection to induce coagulation (2.5% citric acid), curd formation in a clear plastic holding tube (10min), followed by separation of curd from deproteinated whey on a nylon conveyer belt. The process resulted in 98.1% removal of the recoverable solids. Recoveries of protein and fat were 99.5 and 99.6%, respectively.Cheese, prepared from a blend of 80% sweet whey and 20% whole milk, contained 33.5% total solids, 16.30% protein, and 11.6% milk fat. Italian Ricotta, prepared from whey ultrafiltered 4.5 to 1, contained 19.8% total solids, 15.9% protein, and 2.4% fat. The pH of Ricotta prepared from the whey and milk blend (80:20) ranged from 5.6 to 5.8, whereas pH of Ricotta prepared from only ultrafiltered whey (4.5 to 1) was 5.7 to 5.9.The process has advantages over other conventional mechanized cheese processes in terms of reduced capital and operating costs. The process is suitable for cheese factories that may wish to produce Ricotta as a protein base for other food products, such as cream cheese, processed cheese, snack food dips, and quiches.

Effect of certain flavour-improving treatments of recombined-fresch milk blend on its heat stability

Effect of certain flavour-improving treatments of recombined-fresch milk blend on its heat stability

Improving the flavour acceptability of recombined milk blended with fresh milk

An evaluation of different means of improving the flavour acceptability of a 50:50 blend of recombined and fresh milks revealed that addition of sucrose (0.2 %), sodium citrate (0.03 %) or diacetyl (0.25 ppm), or raising the solids-not-fat level to 10.0 % were remarkably effective for this purpose. Replacement of la % skimmilk powder used for the preparation of recombined milk, with sweet cream buttermilk powder was somewhat less effective. The improvement in the flavour of blended milk effected by sodium citrate and sodium chloride was also reflected, to a considerable extent, in the flavour of beverage tea whitened with the milk.

Simultaneous Curdling of Soy/Cow's Milk Blends with Rennet and Calcium or Magnesium Sulfate, Utilizing Soymilk Prepared from Soybeans or Full‐Fat Soy Flour

ABSTRACTMixed soy/cow's milk curds were prepared by simultaneous curdling of soy/cow's milk blends, utilizing rennet as cow's milk coagulant and calcium or magnesium sulfate as soymilk coagulant. The method produced curds of similar characteristics (compactness and yield), whether soymilk prepared from soybeans or full‐fat soy flour was used. The effect of a number of process variables on curd characteristics was studied, utilizing a fractional factorial design. Generally, large changes in process variables (23 – 230%) produced relatively small charges in curd characteristics (1 – 16%). Protein contents of raw materials and proximate chemical analyses of pure and mixed milk curds, prepared under conditions yielding maximum curd compactness were determined. Protein recoveries in curd preparation were calculated.

Some Functional Properties of Milk Protein Calcium Co-Precipitates

The present study deals with the effects of methods of preparation on the yield, composition and some functional properties of Ca co-precipitates. Nonfat dry milk and blends of whey powder and nonfat dry milk were used as raw materials. Functional properties such as solubility, water holding capacity, foaming and whipping properties were tested for each co-precipitate. The functional properties of co-precipitates were compared with those of commercial products such as D-100, MP90-C, egg powder and whey powder. The co-precipitates showed better foaming and whipping properties than three of the commercial agents. The solubility of co-precipitates at pH 4–9 was lower than that of the tested commercial agents.

NUTRITIONAL STABILITY OF CORN‐SOY‐MILK BLENDS AFTER DRY HEATING TO DESTROY SALMONELLAE

ABSTRACTEnriched blends of corn meal, soy flour, and nonfat dry milk (CSM) were adjusted to 7 and 10% moisture and inoculated with approximately 103 cells of Salmonella anatum and Salmonella senftenberg per gram of CSM. The blends were stored at ‐18 to 60°C and then tested for salmonellae and nutritional changes. S. senftenberg was more heat resistant than S. anatum. At temperatures of 43, 49, 54, and 60°C, S. senftenberg was killed by dry heat after 13, 10, 8, and 6 days, respectively, independent of product moisture. Smaller nutritional losses were observed at 7% than at 10% moisture. Changes in product color, PER values, vitamins A and C, and available lysine were minimal at temperatures of 43 and 49°C for 13 and 10 days, respectively. At 54 and 60°C for 8 and 6 days, nutrient losses were excessive at 10% moisture.

Utilization of milk proteins as starting materials for other foodstuffs.

The modern food-processing industry is placing more and more emphasis upon the utilization of protein ingredients to provide specific functional properties to a wide range of formulated foods. Isolated milk protein products represent an important and valuable source of protein ingredients due to their recognized superior nutritional, organoleptic and functional properties. This paper provides up-to-date information on the quantities, production processes, composition, general properties, and specific functional properties of the major milk protein products, e.g. caseinates, co-precipitates, lactalbumin, whey protein concentrates and milk blends. The subject of chemical and enzymic modification to improve certain functional properties of milk proteins is considered briefly.

THE QUALITY OF BLENDED RAW MILK IN CREAMERIES IN SOUTH‐WEST SCOTLAND

The quality of raw blended milk going to manufacture at five creameries in southwest Scotland has been surveyed over a two‐year period. Analyses of gross composition, somatic cell count, numbers and types of bacteria present and the concentration of free fatty acid in the milk show that milk quality was of a high standard. However, extended storage of the milk at 6°C indicated that the bacteria in the milk were actively multiplying and the results showed that extended storage of milk at creameries could seriously jeopardize milk quality. The development of lipolysis on extended storage of the milks was associated with the numbers and types of bacteria present in the milk before storage.

The Utilization of Sunflower Protein in Milk-Like Beverages

Sunflower protein concentrates were evaluated as protein sources for milk blends. The nitrogen (N) solubility of sunflower concentrate (SFC) was markedly reduced due to the aqueous diffusion method used to remove the color-producing phenolic acids. Treatment of the SFC slurries with heat, mechanical agitation and emulsifiers were effective in resolubilizing more than 80% of the N. The Polytron mixer, heating to 80°C, and incorporation of Emulsifier-3I8 were particularly effective in obtaining stable protein suspensions. Blending SFC with cows’ milk also improved N solubility and this effect may have been due to the presence of calcium salts. An equal blend of SFC with milk had a low color and flavor profile, and was equivalent to the soy milk blend in chemical score.

Tricalcium Phosphate as an Insect Suppressant in Flour and CSM

When large quantities of CSM (a blend of cornmeal, soy flour, dry milk, vitamins, and minerals) containing 2% Ca3 (PO4)2 were shipped from the United States to South America, tricalcium phosphate suppressed the development of large populations of Tribolium castaneum (Herbst), the principal insect found in the CSM, during 6 and 7 months of storage in heavily infested warehouses. Tricalcium phosphate in similar quantities of flour suppressed the development of large populations of T. castaneum, Rhyzopertha dominica (F.), Lasioderma serricorne (F.), Tenebroides mauritanicus (L.), and an unidentified moth.