Rainer Stamminger

Impact of wash cycle time, temperature and detergent formulation on the hygiene effectiveness of domestic laundering

Investigation of the effect of temperature and duration of the laundering process with and without activated oxygen bleach (AOB)‐containing detergent on the hygienic effectiveness of laundering.

Water Consumption in the Kitchen – A Case Study in Four European Countries

As there is a limited availability of information on the domestic water consumption through kitchen taps, data collected in a study on dishwashing habits in four European countries has been analysed to gather common habits in the water end-use of households. This paper provides empirical data based on water consumption measurements in 81 households. With the help of a simultaneous webcam observation of the kitchen sink, it was possible to assign the metered consumption data to a specific water use, such as cleaning, drinking or cooking. Water end-use has been analysed with this approach at a very deep level. The study shows that there are, in some measure, large country-specific differences in diurnal water use, as well as in the composition of kitchen activities. Furthermore, the research findings indicate that small households use much more water per person and day than bigger households. This is rather important as demographic shifts are causing a decreased average household size - particularly in urban areas - and, therewith, a growing demand. Water-saving measures at the household and individual level should meet this trend. This paper, therefore, also provides information on to what extent particular kitchen tasks are influential for water consumption in the kitchen, respectively, which activities are important to concentrate on for consumer advice regarding water conservation.

Impact of ultraviolet radiation treatments on the physicochemical properties, antioxidants, enzyme activity and microbial load in freshly prepared hand pressed strawberry juice.

Freshly prepared, hand-pressed strawberry fruit juice was exposed to ultraviolet radiation (254 nm) at room temperature (25 ℃ ± 1 ℃) for 15, 30 and 60 min with 0 min serving as control. Results revealed decrease in pH, total soluble solids and titratable acidity, while colour parameters (L*, a* and b* values) and clarity of juice (% transmittance) increased significantly. All the results corresponded to exposure time to ultraviolet radiation. Bioactive compounds (total phenolics, ascorbic acid and anthocyanins) decreased along with a recorded reduction in polyphenol oxidase enzyme and 1,1-diphenyl-2-picryl hydrazyl radical scavenging activities, which were again dependent on exposure time. Results on the microbial studies showed significant reduction by 2-log cycles in aerobic plate count as well as in total yeast and mould counts. Though negative results were observed for certain parameters, this is the first time it was endeavoured to demonstrate the impact of ultraviolet radiation radiation on freshly prepared, hand-pressed strawberries juice.

Measuring changes in internal meat colour, colour lightness and colour opacity as predictors of cooking time.

Consumers and cooks often assess the degree of doneness of roasted beef by the internal meat colour. Real-time colour measurement of the cooking process is therefore developed in order to determine the degree of doneness, and thus the end of the cooking process, by the internal meat colour. The colour values (X, Y, Z) provided by the true colour sensor show significant variation within initial values and end values. Change in colour lightness caused by the increase of meat colour opacity is dominant. Calculating the first deviation of the Y values (dY/dt) indicates that most rapid changes in lightness are within a temperature range of 42°C and 56°C. At this temperature, the degree of meat doneness is still assumed to be rare, but it is possible to predict the time needed from this point until the desired degree of doneness is reached.

Washing Machines in Europe – Detailed Assessment of Consumption and Performance

Abstract Washing machines in Europe have to comply with regulations fixed in the Energy Label and Ecodesign legislation. They require declaration of the specific consumption and performance values which are deduced as average values from tests on three different treatments. Detailed data about the individual tests are normally not available to the public but just kept in the technical documentation of the manufacturer. Within the ATLETE II project 62 washing machines were measured to verify their compliance with the declared value. As this was an EU funded project all data are now also publicly available. This set of detailed measured data was used first to get a deeper inside into the performances and consumption values of the specific parameters and second to see how different the approaches are between manufacturers to achieve the same or similar declaration values. Additionally it could be shown that there are significant differences between those programmes used for the declaration and those offered as “normal” programmes to the consumer.

Consumers Perceptions and Preference for Strawberries—A Case Study from Germany

Amid a wide array of fruits available in the international market, strawberry has gained high praise among consumers for its unique taste and health benefits. Today’s consumers are more knowledgeable and they are in demand of high quality, nutritionally versatile, and safer plant produce. This has forced both researchers and manufacturers to monitor food production, transportation, and marketing. Based on this background, a detailed ‘online, web-based survey’ was conducted in Germany, which involved consideration of various criteria and consumers’ preferences for strawberries, relevant to the buying behavior, physical attributes, sensorial and nutritional qualities, storage trends, and gastronomy. Our questionnaires were designed based on available research reports/database on strawberries, common knowledge of consumers, and discussions made with local farmers. Results showed frequency of strawberries consumption to be dominated during spring/summer (˜46%). In addition, the majority of the consumers preferred to have strawberries without any physical injuries (˜43%), while an equal percentage of them still accepted strawberries with visible squashy spots (˜43%). Overall, consumers preferred strawberries with uniform color (˜43%), sweet taste (˜66%) with intense or fruity aroma (˜92%) and moderately juicy (˜58%). Results generated in this survey highlight the demands and preferences of consumers as well as indicated certain major gaps that require to be filled along the strawberry production chains for better marketability. Being a first detailed survey, this report is envisaged to be of immense help in enhancing needs and preferences of consumers for strawberries not only in Germany, but also for consumers and growers the world over.

Construction of a Virtual Washing Machine

Abstract In the past years some researches were conducted to model laundry washing in the automatic washing machine. The most studies, however, were focused to some aspects of the automatic laundry washing (e. g. spinning cycle) and not on the washing process as whole. In this paper a model of a washing machine is presented that is based on measured data of 9 different washing machines with rated capacity between 5 kg and 11 kg, which are produced by six different manufacturers. The proposed approach is based on multiple linear regression analysis to extract the systematic, model independent behavior of washing machines and is used to calculate the consumption of the water, energy and detergent in dependence of the rated capacity, washing temperature, duration of the main wash, load size and washing performance.

How Effective are Alternative Ways of Laundry Washing

Abstract Laundry washing consumes resources. It is therefore a clear task for everyone, especially the industry and the consumer, to try to reduce the amount of resources needed as much as possible. Many possibilities and alternatives to the classical cleaning process using a washing machine and a readily formulated detergent are in discussion and are offered to the consumer. Task of this study is to investigate the effectiveness of some of these alternative methods to see whether the task to save resources can be accomplished by them. This is done by carrying out washing performance tests in a common household washing machine using stain monitors and stain strips as indicators for the washing effect in a 30°C and 60°C cotton program and comparing those alternatives (soap nuts, soapwort, two kind of wash-balls) with the use of regular detergent and washing with pure water. As result it is shown, that none of the investigated alternative cleaning methods does deliver any washing effect better than the result achieved with pure water, besides for soapwort that also included other surfactants. Interesting to note that on most stains the use of just 50% of the detergent delivers already a cleaning performance not much lower as 100% of detergent does provide.

Larger Washing Machines and Smaller Household Size – How Can They Fit Together? Simulation of a Sustainable Use of Washing Machines

Abstract In order to simulate the usage of washing machines by the consumer, a concept of a “virtual washing household” is developed that, to some extent, behaves as a real life household. As essential part of this virtual household is the virtual washing machine in which washing cycles are conducted in dependence of the washing parameters, household size and behavioral parameters. The concept stipulates that a washing cycle is conducted only when the household has enough laundry collected, so that the loading capacity of the washing machine is used, otherwise the houshold waits. Houshold, however, washes the laundry despite the loading capacity restrictions when a certain, waiting time (defined by the houshold) is elapsed. The consequences of all washing cycles during one year are calculated in terms of CO2 equivalent emissions caused by the energy, water and detergent consumed for reaching a well-defined level of washing performance. This model offers a high range of possibilities to simulate some of the consumers behavioral patterns and so helps to identify an optimal washing behavior for different sizes of washing machines.

Using Fabric Softeners, Drying and Ironing in Germany

Abstract During the annually arranged Action Day Sustainable Washing on May 10th, 5284 questionnaires about laundry treatment were collected from private people in Germany with the aim of obtaining information about consumer behaviour and attitudes towards sustainability. This is a non-representative census as only 15% of all respondents were male. Nevertheless, relative distribution and correlation provide a relevant insight into consumers’ behaviour towards washing, drying and ironing. The most important results of the analysis can be summed up as follows: – Nearly 50% of the respondents own a laundry-dryer. – Nearly one third of all respondents never use fabric softeners. The prevention of ecological damage was the reason for not using fabric softeners for 30% of the respondents. – About one fourth of all respondents always use fabric softeners, with younger people having a significantly higher attitude towards using them. – Under good weather conditions, about 90% of the respondents choose energy-saving alternatives to dry their laundry. – The average weekly time spent on ironing is about two hours on average of all respondents who gave information. The analysis shows that laundry treatment beyond the pure washing process is a multi-faceted process with several starting points of improvement in favour of sustainable handling.