Dairy Factory Research Articles

Antibiotic residues and aflatoxin M1 contamination in milk powder used in Tehran dairy factories, Iran

BACKGROUND: The presence of aflatoxin M1 (AFM1) andantibiotic residues in milk and milk products is a public healthconcern. Milk and milk powder have the potential forintroducing AFM1 and antibiotic into human diet. In recentyears, milk powder has been used on a large scale in dairyfactories. Consequently, antibiotic residues and aflatoxincontamination control in these products has gained importance.OBJECTIVES: The aim of this survey was to determine the levelof β-lactam and tetracycline antibiotic residues and also AFM1contamination of milk powder used in Tehran dairy factories.METHODS: During 12 months (September 2011 to September2012), 240 samples of milk powder were collected from tenTehran dairy factories. All samples were analyzed for thepresence of AFM1 using ELISA technique. In addition,antibiotic residues were determined by BetaStar Combo test, arapid assay for both β-lactam and tetracycline antibiotics.RESULTS: The samples depicted positive results i.e. 30% and17.5% for β-lactam and tetracycline antibiotics, respectively.Also, AFM1 was found in 155 cases (64.6%) with an averageconcentration of 29.85 ± 18.99 ng/ L. CONCLUSIONS:The resultsshowed the milk powder used by dairy factories is safe in respectof AFM1 contamination and antibiotic residues in Tehran.

The evolution of the Dutch dairy industry and the rise of cooperatives: a research note

Abstract:Economic historians tend to explain the rise of the cooperative form in agriculture from the advantage of cooperative over private factories in reducing transaction costs with suppliers. This study provides a first test of this thesis using data on 1,130 dairy factories in The Netherlands. Indeed, we find that cooperative factories performed significantly better than private factories. The persistence of private factories in certain regions can be explained by first-mover advantages.

Biodegradation by bioaugmentation of dairy wastewater by fungal consortium on a bioreactor lab-scale and on a pilot-scale

A fungal consortium including Aspergillus niger, Mucor hiemalis and Galactomyces geotrichum was tested for the treatment of dairy wastewater. The bio-augmentation method was tested at lab-scale (4 L), at pilot scale (110 L) and at an industrial scale in Wastewater Treatment Plants (WWTP). The positive impact of fungal addition was confirmed when fungi was beforehand accelerated by pre-culture on whey (5 g/L lactose) or on the dairy effluent. Indeed, chemical oxygen demand (COD) removal yields increased from 55% to 75% for model medium, diluted milk. While after inoculation of an industrial biological tank from a dairy factory with the fungal consortium accelerated by pre-cultivation in a 1000 L pilot plant, the outlet COD values decreased from values above the standard one (100 mg/L) to values in the range of 50–70 mg/L. In addition, there was a clear impact of fungal addition on the ‘hard’ or non-biodegradable COD owing to the significant reduction of the increase of the COD on BOD5 ratio between the inlet and the outlet of the biological tank of WWTP. It was in the range of 451%–1111% before adding fungal consortium, and in the range of 257%–153% after bio-augmentation with fungi. An inoculated bioreactor with fungal consortium was developed at lab-scale and demonstrated successfully at pilot scale in WWTP.

Abiotic and Microbiotic Factors Controlling Biofilm Formation by Thermophilic Sporeformers

One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon sequencing analysis was carried out on milk, final products, and fouling samples taken from dairy concentrate production lines. The analysis of these samples revealed the presence of DNA from a broad range of bacterial taxa, including a majority of mesophiles and a minority of (thermophilic) spore-forming bacteria. Enrichments of fouling samples at 55°C showed the accumulation of predominantly Brevibacillus and Bacillus, whereas enrichments at 65°C led to the accumulation of Anoxybacillus and Geobacillus species. Bacterial population analysis of biofilms grown using fouling samples as an inoculum indicated that both Anoxybacillus and Geobacillus preferentially form biofilms on surfaces at air-liquid interfaces rather than on submerged surfaces. Three of the most potent biofilm-forming strains isolated from the dairy factory industrial samples, including Geobacillus thermoglucosidans, Geobacillus stearothermophilus, and Anoxybacillus flavithermus, have been characterized in detail with respect to their growth conditions and spore resistance. Strikingly, Geobacillus thermoglucosidans, which forms the most thermostable spores of these three species, is not able to grow in dairy intermediates as a pure culture but appears to be dependent for growth on other spoilage organisms present, probably as a result of their proteolytic activity. These results underscore the importance of abiotic and microbiotic factors in niche colonization in dairy factories, where the presence of thermophilic sporeformers can affect the quality of end products.

Selected lactic acid bacteria as a hurdle to the microbial spoilage of cheese: Application on a traditional raw ewes' milk cheese

To evaluate the efficacy of lactic acid bacteria (LAB) to improve the hygienic safety of a traditional raw milk cheese, the raw ewes' milk protected denomination of origin (PDO) Pecorino Siciliano cheese was used as a model system. Different Pecorino Siciliano curds and cheeses were used as sources of autochthonous LAB subsequently used as starter and non-starter LAB. These were screened for their acidification capacity and autolysis. Starter LAB showing the best performance were genotypically differentiated and identified: two strains of Lactococcus lactis subsp. lactis were selected. From the non-starter LAB, Enterococcus faecalis, Lactococcus garvieae and Streptococcus macedonicus strains were selected. The five cultures were used in individual or dual inocula to produce experimental cheeses in a dairy factory for which production was characterised by high numbers of undesirable bacteria. At 5-month of ripening, the experimental cheeses produced with LAB were characterised by undetectable levels of enterobacteria and pseudomonads and the typical sensory attributes.

Environmental Life Cycle Assessment of a Galician cheese: San Simon da Costa

Abstract Cheese production has always been the standard way of preserving milk. This is the second most consumed dairy product in Spain (ca. 6.2 kg per year and person), with more than 100 different cheeses available in the market. However, only 26 types are labelled with a Protected Designation of Origin (PDO), a symbol of quality recognition. In this study, an environmental Life Cycle Assessment (LCA) was performed to identify and quantify the environmental impacts (cradle-to-grave perspective) derived from the manufacture of one of the most popular and traditional PDO Galician cheeses: San Simon da Costa cheese. The most critical steps throughout the chain were identified. As expected, milk production at the dairy farm is the main environmental hot-spot in all categories assessed, with contributions ranging from 63% to 89%. Both feed production (mainly fodder) and on-farm emissions derived from enteric fermentation and manure management were the highest contributing farming activities. Cheese making activities should also be considered, with emphasis on impacts associated with the smoking process, the heating system and wastewater treatment. The studied dairy factory has not implemented a system for whey recovery due to its small-scale production. Thus, whey waste mixed with the wastewater effluent is sent to the municipal wastewater treatment plant. Therefore, the valorisation of whey into whey powder was considered as an alternative for improvement. Using this process modification, it is possible to achieve reductions in the environmental profile of the PDO San Simon cheese of up to 15% in categories such as eutrophication. In addition, attention must be paid to the environmental loads of whey powder production arising from electricity and heating requirements.

Expression, purification, crystallization and preliminary X-ray diffraction analysis of a lactococcal bacteriophage small terminase subunit.

Terminases are enzymes that are required for the insertion of a single viral genome into the interior of a viral procapsid by a process referred to as 'encapsulation or packaging'. Many double-stranded DNA viruses such as bacteriophages T3, T4, T7, λ and SPP1, as well as herpes viruses, utilize terminase enzymes for this purpose. All the terminase enzymes described to date require two subunits, a small subunit referred to as TerS and a large subunit referred to as TerL, for in vivo activity. The TerS and TerL subunits interact with each other to form a functional hetero-oligomeric enzyme complex; however the stoichiometry and oligomeric state have not been determined. We have cloned, expressed and purified recombinant small terminase TerS from a 936 lactococcal bacteriophage strain ASCC454, initially isolated from a dairy factory. The terminase was crystallized using a combination of nanolitre sitting drops and vapour diffusion using sodium malonate as the precipitant, and crystallization optimized using standard vapour-diffusion hanging drops set up in the presence of a nitrogen atmosphere. The crystals belong to the P2 space group, with unit-cell parameters a=73.93, b=158.48, c=74.23 Å, and diffract to 2.42 Å resolution using synchrotron radiation. A self-rotation function calculation revealed that the terminase oligomerizes into an octamer in the asymmetric unit, although size-exclusion chromatography suggests that it is possible for it to form an oligomer of up to 13 subunits.

Failure mode and effect analysis for dairy product manufacturing: Practical safety improvement action plan with cases from Turkey

The incidence of contamination of raw milk and dairy products by biological and chemical hazards is a major problem all around the world. Systematic risk control at each stage of the process is required to minimize or eliminate failures in the manufacturing process. The quantitative risk analysis method, Failure Mode and Effect Analysis (FMEA), was applied for the risk analysis of six dairy products that are widely consumed in Turkey. Comprehensive real data collected from 75 food safety audits carried out in 30 dairy factories between 2006 and 2011 were used to implement the method. Possible failure modes in the processes were identified and the potential risks for each failure mode were analyzed. Risk priority numbers were calculated to identify the risk level of each potential failure. Generally speaking, the highest total risk priority number was calculated for the biological failures, which were followed by the chemical failures in all processes. Physical failures were found to pose the lowest risk. Failures were commonly observed in companies that were applying obsolete technologies, using intensive human handling, and employing staff members with no previous food processing and hygiene training. It is concluded that implementing the FMEA methodology in dairy industry will decrease the possibility of failure noticeably in all the manufacturing processes studied. Results of this study can be used by the manufacturers in different parts of the world to produce safer dairy products, since almost all dairy products share common manufacturing stages.

EDTA in environments subjected to disposal of dairy effluent from processing plants

The presence of Ethylenediaminetetraacetic acid (EDTA) in environments related to the disposal of dairy effluent has been investigated. An HPLC-UV analytical method was used to determine concentrations of EDTA in soil, surface and ground waters. Method detection limits were 1.5 mg/kg (dry weight) for soil, 1 µg/L for surface water and 2 µg/L for groundwater. A quasi one-dimensional vertical mixing model and a numerical simulation of the hydrodynamic processes (the 3DD hydrodynamic model) were applied to simulate the dispersion of EDTA discharged from a large-scale dairy factory into a relatively small river. Based on the modelling results, large volumes of dairy wastewater discharged into the local river had no significant effects on the concentration of EDTA. Analytical results of EDTA in soil and groundwater indicated that there was no concern about the irrigation of dairy sludge onto pasture land. EDTA was, however, detectable in the soil and groundwater, and heavy metals appear to be transported into the groundwater with EDTA chelates in the pasture area irrigated by the dairy wastewater over periods of time.

Dairy Factory Wastewater from Cumulative Point of View–A Case Study

It is needless to mention that, milk has the most appropriate and balanced combination among various foods that human feed on them daily and because of this fact milk is commonly called the perfect food. Therefore, milk and dairy products industries are one of the most important and necessary industries in all human societies. However, wastewater from this industry includes a variety of pollutants. The nature and combination of milk industry wastewater depends on the type of process being done on milk in factory and also type and combination of products that are produced in factory. In this study, the output effluent of a dairy factory was selected for investigation. Firstly, dairy wastewater specifications were introduced. Then, during 63 days, wastewater of plant was sampled ten times. Afterwards, temperature, nitrate, phosphate, BOD, COD, TSS, TDS, DO, pH, NH4, salt were measured by special devices and methods. Afterwards, by correlation analysis the impressibility of each parameter than the other variables was evaluated. The amount of these factors was compared with existing standard. Then, the correlation coefficient of these factors was evaluated by using SPSS software.

At-line measurement of lactose in dairy-processing plants

Environmental and process control applications have needs for sensors that operate continuously or repeatedly, making them applicable to batch measurement and flowing product stream measurement. Additionally, for lactose monitoring in dairy-processing plants, the sensors must have sufficient flexibility to handle a wide range of substrate concentration and be resilient to withstand wide pH excursions brought about by frequent exposure to clean-in-place chemicals that happen without any warning. This paper describes the development and trialling of an at-line lactose biosensor that meets the needs of the dairy industry for loss monitoring of lactose in dairy-processing plants by the combination of a third-generation enzyme biosensor with a sequential injection analyser. Results, both from grab sample analysis and an at-line factory prototype, are shown from their operation when installed at a Fonterra dairy factory (New Zealand) during the 2011-2012 season. Previous sensor fabrication methods were converted to a single-step process, and the flow-through cell was adapted to bubble-free operation. The lactose concentration in wastewater-processing streams was successfully monitored by taking and analysing samples every 2-3 min, semi-continuously, for 3 months by an unskilled operator. The Fonterra site flushes approximately 100-300,000 L of wastewater per hour from its lactose plant. In the 2011-2012 season, the daily mean lactose content of this wastewater varied significantly, from 0.0 to 8.0% w/v (0-233,712 μM) and equated to substantial total losses of lactose over a 6-month period. These lactose losses represent lost saleable or useable product.

Using Life Cycle Assessment methodology to assess UHT milk production in Portugal

Milk and dairy products constitute an important ingredient in the human diet. Ultra-high temperature (UHT) milk is the main dairy product consumed in Portugal and its production entails large inputs of resources which derive on negative environmental effects such as nutrient enrichment of the ecosystem and climate change.In this study, Life Cycle Assessment (LCA) methodology was considered for the environmental assessment of packaged UHT milk produced in Portugal, including simple (whole, semi-skimmed and skimmed) and cocoa milk from a cradle-to-gate perspective and to identify the environmental hot spots. Results showed that the production of the raw milk in the dairy farm is the main hot spot in almost all the categories under assessment mainly due to the emissions from enteric fermentation, manure management and fertilisers production and application. Furthermore, on-site emissions derived from dairy factory are remarkable together with the packages and energy requirements production. The values reported in this study are in the range of other related papers. However, differences were also identified due to several reasons such as allocation approach, data sources, characterisation factors, farm management regimes and assumptions considered. Therefore, these aspects should be carefully addressed and sensitivity to the assumptions and uncertainty of the results should be evaluated.

Food Safety Systems in a Small Dairy Factory: Implementation, Major Challenges, and Assessment of Systems' Performances

The present study describes the implementation of a food safety system in a dairy processing plant located in the State of São Paulo, Brazil, and the challenges found during the process. In addition, microbiological indicators have been used to assess system's implementation performance. The steps involved in the implementation of a food safety system included a diagnosis of the prerequisites, implementation of the good manufacturing practices (GMPs), sanitation standard operating procedures (SSOPs), training of the food handlers, and hazard analysis and critical control point (HACCP). In the initial diagnosis, conformity with 70.7% (n=106) of the items analyzed was observed. A total of 12 critical control points (CCPs) were identified: (1) reception of the raw milk, (2) storage of the raw milk, (3 and 4) reception of the ingredients and packaging, (5) milk pasteurization, (6 and 7) fermentation and cooling, (8) addition of ingredients, (9) filling, (10) storage of the finished product, (11) dispatching of the product, and (12) sanitization of the equipment. After implementation of the food safety system, a significant reduction in the yeast and mold count was observed (p<0.05). The main difficulties encountered for the implementation of food safety system were related to the implementation of actions established in the flow chart and to the need for constant training/adherence of the workers to the system. Despite this, the implementation of the food safety system was shown to be challenging, but feasible to be reached by small-scale food industries.

Transfer of eight phthalates through the milk chain — A case study

This survey determined the levels of eight phthalates – i.e. dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzylbutyl phthalate (BzBP), di(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP) and di-n-octyl phthalate (DnOP) – in several Belgian milk and dairy products. Samples were obtained from various farms, a dairy factory and from different shops in order to investigate phthalate contamination “from farm to fork”. At several stages in the milk chain, product contamination with phthalates – mostly DiBP, DnBP, BzBP and DEHP – was observed. At farm level, the mechanical milking process and the intake of phthalate containing feed by the cattle were found to be possible contamination sources. At industry and retail level, contact materials including packaging materials were additional contamination sources for phthalates in milk and dairy products.

Industrial and urban organic wastes increase soil microbial activity and biomass

Microbial processes have been used as indicators of soil quality, due to the high sensitivity to small changes in management to evaluate, e.g., the impact of applying organic residues to the soil. In an experiment in a completely randomized factorial design 6 x 13 + 4, (pot without soil and residue or absolute control) the effect of following organic wastes was evaluated: pulp mill sludge, petrochemical complex sludge, municipal sewage sludge, dairy factory sewage sludge, waste from pulp industry and control (soil without organic waste) after 2, 4, 6, 12, 14, 20, 28, 36, 44, 60, 74, 86, and 98 days of incubation on some soil microbial properties, with four replications. The soil microbial activity was highly sensitive to the carbon/nitrogen ratio of the organic wastes. The amount of mineralized carbon was proportional to the quantity of soil-applied carbon. The average carbon dioxide emanating from the soil with pulp mill sludge, corresponding to soil basal respiration, was 0.141 mg C-CO2 100 g-1 soil h-1. This value is 6.4 times higher than in the control, resulting in a significant increase in the metabolic quotient from 0.005 in the control to 0.025 mg C-CO2 g-1 Cmic h-1 in the soil with pulp mill sludge. The metabolic quotient in the other treatments did not differ from the control (p &lt; 0.01), demonstrating that these organic wastes cause no disturbance in the microbial community.

BIOLOGICAL TECHNIQUE IN REDUCING THE WATER DISSOLVED NUTRIENTS IN THE DAIRY WASTEWATER BY USING DUCKWEED

The experiment was conducted in an ideal field of non-fully control studying the impact of the arbitration included duckweed plant in water to remove the dissolved nutrients (ammonia, nitrite, nitrate and phosphorus) from waste water of dairy products factory adopted in a period of ten days. The results revealed the treatment of duckweed plant with wet weight 5g/L and another treatment (control) without waste water plant in the dairy factory a gradual reduction of plant nutrients was noticed from the first day except ammonia, which did not show a high concentration during the first days until the fifth day of the two transactions, The total removal minerals of the plant and without plants follow: ammonia 72,73, 27,27%, nitrite, 97,87, 74,40%, nitrates, 83,40, 79,40%, on the tenth day respectively, this means that with plant one higher than without plants, The phosphorus values, 43,81, 48,66%, respectively, on the eighth day of the experiment. Protein and moisture percentages raised to 39,72, 7,66%, respectively, after growing the Duckweed in dairy wastewater if compared with these grown without. When the duckweed grown in dairy wastewater entered in components in fish fed-stuff containing by 5 and 10 %, it an increase of protein, carbohydrates, and ash, the proportions in the duckweed plant, were noticed where the percentages were 40,02, 22,51, 27,02%, respectively, and duckweed plant reduced the rates of water moisture, fat, fiber, as it reached in the duckweed ratios 6,69, 0,37, 3,39% respectively.

Environmental life cycle assessment of a dairy product: the yoghurt

Purpose The dairy sector covers multiple activities related to milk production and treatment for alimentary uses. Different dairy products are available in the markets, with yoghurt being the second most important in terms of production. The goal of this study was to analyse from a cradle-to-grave approach the environmental impacts and energy balance derived from the yoghurt (solid, stirred and drinking yoghurts) manufacture process in a specific dairy factory processing 100 % Portuguese raw milk.

Environmental performance of a Portuguese mature cheese-making dairy mill

Abstract An environmental assessment was carried out in order to quantify the environmental consequences of the life cycle of mature cheese production from a cradle-to-gate perspective and to identify the environmental hotspots. To do so, an international cheese-making dairy factory located in Portugal was assessed in detail and inventory data for the different production steps (milk production at dairy farm, cheese manufacturing and whey transformation at industrial dairy factory) were taken on-site. The production line at the industrial dairy factory presents two main products: mature cheese and whey powder. The environmental burdens were allocated between both products based on an economic allocation approach as baseline. However, different methodological approaches, mass allocation and no allocation (assigning the whole environmental load of the production line to the cheese), were also applied in this study. Dairy-farm-related activities play an important role concerning different environmental impact categories, namely acidification (91%), eutrophication (86%), global warming (82%), land competition (99%) and photo-oxidants formation (69%) due to on-farm emissions such as methane from enteric fermentation, ammonia from manure management, combustion emissions from agricultural machineries as well as land requirements for animal fodder production. From cheese-making, the most important contributions are related to abiotic depletion (55%), ozone layer depletion (51%) and cumulative energy demand (55%) mainly due to the energy requirements in the different production processes and to the distribution of input goods up to the dairy gate. Improvement alternatives for the environmental key factors within the limits of the dairy factory were proposed based on a reduction of energy consumption, the use of a more environmentally friendly fuel in the boilers and the use of new trucks with lower exhaust emissions. According to the results, it has been demonstrated that it should be possible to slightly reduce the environmental profile in some impact categories (acidification, eutrophication, global warming and photo-oxidants formation) without involving significant economic investment.

Correlation between precipitation and geographical location of the δ2H values of the fatty acids in milk and bulk milk powder

Hydrogen isotope ratios (δ2H) have become a tool for food traceability and authentication of agricultural products. The principle is that the isotopic composition of the produce is influenced by environmental and biological factors and hence exhibits a spatial differentiation of δ2H. This study investigates the variation in δ2H values of New Zealand milk, both in the bulk powder and individual fatty acids extracted from milk samples from dairy factories across New Zealand. Multivariate statistical analyses were used to test for relationships between δ2H of bulk milk powder, milk fatty acid and geographical location. Milk powder samples from different regions of New Zealand were found to exhibit patterns in isotopic composition similar to the corresponding regional precipitation associated with their origin.A model of δ2H in precipitation was developed based on measurements between 2007 and 2010 at 51 stations across New Zealand (Frew and Van Hale, 2011). The model uses multiple linear regressions to predict daily δ2H from 2 geographic and 5 rain-weighted climate variables from the 5×5km New Zealand Virtual Climate Station Network (VCSN). To approximate collection radius for a drying facility the modelled values were aggregated within a 50km radius of each dairy factory and compared to observed δ2H values of precipitation and bulk milk powder. Daily δ2H predictions for the period from August to December for the area surrounding the sample collection sites were highly correlated with the δ2H values of bulk milk powder. Therefore the δ2H value of milk fatty acids demonstrates promise as a tool for determining the provenance of milk powders and products where milk powder is an ingredient. Separation of milk powder origin to geographic sub-regions within New Zealand was achieved. Hydrogen isotope measurements could be used to complement traditional tracking systems in verifying point of origin.

Nanofiltration of UHT flash cooler condensates from a dairy factory: Characterisation and water reuse potential

The large consumption of water in the dairy industry makes water reuse a crucial issue. Flash Cooler (FC) condensates from direct ultra high temperature (UHT) treatments were characterised and nanofiltered in order to obtain potentially reusable water depending on the limitations of its end uses. A nanofiltration (NF) pilot plant (1.6m2 membrane area) with a SelRO MPS-34 2540 B2X (Koch Membrane Systems) was used for these purposes. The influence of operating conditions (transmembrane pressure (TMP), temperature, time and water recovery) on permeate flow rate (J) and quality (conductivity, chemical oxygen demand (COD), total organic carbon (TOC) and Ca2+) was studied. Heating (taking into account the thermal potential of condensates) and other miscellaneous objectives were achieved, a volume concentration ratio (VCR) of 8 being set as a design parameter. The experimental data was used to design a NF plant with 20m3/h feed capacity whose savings and operating costs were estimated at 2.807 and 0.777€/m3, respectively.