Svetlana Rodgers

Preserving non-fermented refrigerated foods with microbial cultures—a review

The use of microbial cultures offers a natural temperature-responsive preservation method. The inhibition at refrigeration temperatures is associated with production of low molecular weight compounds including lactic acid, hydrogen peroxide and bacteriocins. Bacteriocin-producing cultures are not effective against Gram-negative bacteria and special strategies are needed. The role of intrinsic and extrinsic factors in the antibiosis is reviewed with the examples in a range of refrigerated foods. The suggested protocol for practical applications includes the selection of cultures, screening in microbiological media, trials in food and the strategies to enhance the inhibitory effect.

Technological innovation supporting different food production philosophies in the food service sectors

Purpose – The purpose of this paper is to identify technological challenges and innovative solutions in each of the food production philosophies in the food service sector, namely: industrial cuisine, fast food and fresh food.Design/methodology/approach – The paper reviews industry reports on cooking equipment and preparation techniques. Conceptual links are made with possible future developments as well as operational/strategic advantages they represent.Findings – Innovation in food preparation commands multi‐disciplinary approaches stemming from engineering and food science. Industrial cuisine would benefit from automation, units with intensive heating, robust food product design and shelf‐life extension; fast food from reduced oil absorption by food, better cooking oils, automation and short frying time; and fresh food from rapid cooking, visually appealing serving units and analytical instrumentation for testing raw produce. Future innovations may originate in the field of robotics, food engineering a...

Selecting a food service system: a review

Purpose – The selection of a food service system (cook‐chill, cook‐freeze and cook‐hot‐hold) is a major strategic initiative, which involves a large capital investment. Each system has specific advantages and disadvantages and each is most suited to a particular set of operational conditions. The paper provides an inventory of data on the efficiency of the systems, identifies deficiencies as well as future needs and tools in the research in this field.Design/methodology/approach – An overview of the studies supporting the decision‐making process – the identification of the need for a system, evaluation of different systems, system selection, implementation and analysis of outcomes.Findings – The paper demonstrates the lack of up‐to‐date objective data substantiating the benefits of the systems in the commercial and institutional hospitality sectors. It suggests a conceptual framework linking food preparation technologies with the elements of strategic marketing as well as statistical techniques, which can...

Applied research and educational needs in food service management.

Purpose – The paper aims to provide a better understanding of food service technologies, applied research and technical literacy needs in hospitality.Design/methodology/approach – Reviews the applied research in food services and the technical literacy needed to interpret and benefit from it.Findings – The summary of research is provided in the subject areas identified by QAAHE (2000): food safety management, food quality management and product development; equipment and facility layout/design; operational planning and modelling; as well as market and consumer related aspects. Underpinning scientific disciplines and operational/ strategic benefits of the described studies as well as the three tiers in the educational pathways in food production are described.Practical implications – The research findings can be used as a source of competency‐building by practitioners and educators.Originality/value – The paper identifies the main types of research and develops conceptual links between the scientific funda...

Potential applications of protective cultures in cook-chill catering

Abstract Extended shelf-life cook-chill technology is widely used by modern food services. However, it poses a number of food safety risks. There is a limited choice of suitable preservation methods for applications in catering. Bacteriocinogenic protective cultures (PCs) offer temperature-responsive preservation and a ‘natural’ image. The knowledge of the dynamic of inhibition and factors effecting it is needed to ‘design’ products protected by this method. The suggested protocol for PC applications covers the inhibition enhancing strategies and possible ways of protecting PCs during processing.

Inhibition of Non-proteolytic Clostridium botulinum with Lactic Acid Bacteria in Extended Shelf-Life Cook-Chill Soups

The possibility of protecting cook-chill foods with microbial cultures against the risk of botulism was demonstrated. Three commercial soups were incubated with Clostridium botulinum 17B (103 spores/g) and protective cultures (PCs) during 10–15 days at 10°C. The PCs populations were enumerated on M17, MRS and maltose tryptic soy agar, C. botulinum—on sorbitol tryptic soy agar, botulinal toxin was detected by the immunoassay, bacteriocins—by well diffusion assay. C. botulinum did not grow in two soups with low pH (5.2–5.5) and was unaffected by the PCs. In seafood chowder (pH 6.2) C. botulinum populations reached 108 cfu/g. The co-incubation with the PCs, nisin-producing Lactococcus lactis (107 cfu/g) or pediocin-producing Pediococcus pentosaceus (3×108 cfu/g) singularly and as a mixture, prevented toxigenesis as well as reduced the product pH to 4.8–5.0 and C. botulinum populations to undetectable levels. Color, mouth-feel, texture, flavor and the overall acceptability of seafood chowder was not affected by the presence of the PCs.

Technological developments and the need for technical competencies in food services.

The growing scale of institutional and commercial food services poses a technological challenge of producing large quantities of high quality meals in terms of their safety, sensory and nutritional attributes. Developments in food service technology and systems (cook-freeze, cook-chill and others) allow the replacement of fast food with the service of cooked meals, which are often nutritionally superior. Reliance on equipment, packaging and technological ‘know-how’ makes food service operations more complex. Operators have to minimise the impact of the numerous steps in the production process, the fundamental weaknesses of cook-chill food safety design, coupled with the practical limitations of Hazard Analysis Critical Control Points management, the potential unevenness of temperature distribution and product deterioration during storage. The fundamental knowledge of food science and microbiology, engineering and packaging technologies is needed. At present, the ‘high tech’ options, which can improve a product’s nutritional value, such as natural preservation hurdles or functional meals, are not used in practice.

Deriving Strategic Advantages from Extended Shelf-Life Foods in the Hospitality Sector

Abstract The perishability of food service products can be reduced by refrigeration and packaging technologies. Both the institutional and commercial sectors take advantage from the “time buffer” between food production and consumption in bulk food production. Setting up a central production unit requires the knowledge of technological and operational concepts. It consists of conceptualization, product development and implementation stages. First, the size of the capital investment required, the availability of current food service technologies, reports on operational efficiencies as well as mandated food safety measures are analyzed. Second, menu engineering and product development to minimize mechanical damage during bulk preparation and product deterioration during storage/re-thermalization are conducted. Third, the possibility of extension of the product shelf-life, which is linked to the degree of heating, packaging, and “natural” preservation, is explored. The main technical difficulty here is the balance between the severity of processing, which determines food quality, and the acceptable level of food safety risks. The modification of processing to derive operational advantages requires challenge studies, which are expensive. However a complex product is not easily copied by competitors, as it requires investment and technological “know-how.” doi:10.1300/J385v05n02_10

The Potential Role of Latest Technological Developments Including Industrial Gastronomy in Functional Meal Design

ABSTRACT The multidisciplinary futuristic concept of a functional meal (FM), a meal with added health-improving ingredients served in a restaurant setting, represents a high level of complexity in product development. The two main preoccupations in FM design are the reduction of fats and sugars and the increase in fibres and micronutrients. The latest technological advances supporting this concept include the availability of novel functional ingredients, equipment adoptable for “in-house” food production and industrial gastronomy. The latter can be defined as techniques such as freeze-drying, vacuum cooking, gelation, texturising with fibres, and the action of enzymes borrowed from food manufacturing to achieve culinary sensations in small scale preparation. This article describes new meals made of solid yoghurt, square sauce, extra-juicy lobster, soap bubbles, and alginate gloves.

Development of Functional Meals with Bifidobacteria

This article reports the possibility to design functional meals with probiotics, health-improving bacteria of the gut. Such applications require a simple addition of cultures to products. However, their survival at the therapeutic level (>107colony forming units/gram) is the main technological challenge. Operators need assurance that the products they advertise as probiotic actually have sufficient populations of the live bacteria. The aim of the study was to test the viability of the freeze-dried probiotic strain Bifidobacterium animalis ssp. lactis in selected beverages, dishes, and condiments. Viable populations were enumerated using the standard plate count technique on the reinforced clostridial agar. The results showed that the high acidity of products such as vinaigrette and mayonnaise combined with long storage time was detrimental to probiotic survival. In general, items consumed shortly after the culture is added (cold beverages) and those with low acidity (sandwiches, sushi, rice pudding, butter, soy sauce, and buttermilk dressing) are suitable as probiotic carriers.