Food Service Technology最新文献

For many years, sanitarians have specified that the hands of food service workers should be washed and rinsed in warm or hot water to reduce the risk of cross-contamination and disease transmission. In the food service environment, it has been suggested that handwashing with water at higher temperatures contributes to skin damage when frequent handwashing is necessitated, and that insistence on hot water usage is a deterrent to handwashing compliance. Separate handwashing studies involving different water temperatures and soap types (antibacterial versus non-antibacterial) were performed. The ‘glove-juice’ technique was employed for microbial recovery from hands in both studies. Initial work evaluated antimicrobial efficacy based on water temperature during normal handwashing with bland soap. Uninoculated, sterile menstrua (tryptic soy broth or hamburger meat) was used to study the effects of treatment temperatures (4.4°C, 12.8°C, 21.1°C, 35°C or 48.9°C) on the reduction of resident microflora, while Serratia marcescens-inoculated menstrua was used to evaluate treatment effects on the reduction of transient contamination. Results of this first study indicated that water temperature exhibits no effect on transient or resident bacterial reduction during normal handwashing with bland soap. The follow-up study examined the efficacy and skin irritation potential involving water temperatures with antimicrobial soaps. Hands of participants were contaminated with Escherichia coli inoculated ground beef, washed at one of two water temperatures (29°C or 43°C) using one of four highly active (USDA E2 equivalency) antibacterial soaps having different active ingredients (PCMX, Iodophor, Quat or Triclosan). Skin condition was recorded visually and with specialized instrumentation before and after repeated washing (12 times daily), measuring total moisture content, transepidermal water loss and erythema. Overall, the four soap products produced similar efficacy results. Although there were slight increases in Log₁₀ reductions, visual skin irritation, loss of skin moisture content and transepidermal water loss at higher temperatures, results were not statistically significant for any parameter.

Wild deer, antelope and other exotic animals have been hunted and their meat consumed for centuries. Although the game industry is the fastest growing agricultural industry in South Africa, the sale of venison constitutes a mere 2% of the estimated annual gross income of the wildlife industry. This is surprising, since, apart from its nutritional value, South African venison is free of diseases and originates from animals in their natural habitat, without human intervention in genetic selection, the use of growth hormones, insecticides, or pesticides. The perceived prejudice of South African consumers against venison could stem from bad taste experiences as a result of ignorance concerning the meat's preparation. The question arises whether away-from-home consumption in restaurants, hotels and coffee shops could play a role in introducing consumers to the taste of well-prepared venison. This exploratory study investigates the supply of and demand for venison at restaurants in the metropolitan areas of the Eastern Cape, the top hunting region of South Africa. It also deals with the management of menus and restaurant owners’ perceptions about consumers’ interest in venison, since it is argued that away-from-home consumption can only play a role if restaurant owners or chefs include venison on their menus.

A survey of the food service departments in 93 hospitals throughout NSW Australia (covering 51% of hospital beds in the state) was conducted using a mailed questionnaire and the results compared with those from similar surveys conducted in 1986 and 1993. Over the past eight years there has been a significant increase in the proportion of hospitals using cook-chill food service production systems, from 18% in 1993 to 42% in 2001 (P < 0.001). Hospitals with cook-chill systems had better staff ratios than those with cook-fresh systems (8.3 vs. 6.4 beds/full time equivalent staff; p < 0.05), but there was no significant difference in the ratio of meals served per FTE. There was no difference between public and private hospitals in terms of ratios of beds or meals to food service staff. Managers using cook-chill systems reported significantly lower levels of satisfaction with the food service system compared to those using cook-fresh. Two aspects of the services have not changed since the last survey: approximately a quarter of food service departments are still managed by staff without formal qualifications and meal times remain the same, with more than 90% of hospitals serving the evening meal before 5.30 p.m. and a median of 14.25 h gap between the evening meal and breakfast.

Sous-vide technology poses a risk of botulism. Twenty-six catering and retail cook-chill meals were challenged with non-proteolytic Clostridium botulinum (10³ spores/g) and incubated for 10 days at 10 °C. C. botulinum populations were enumerated on salicin tryptic soy agar and background microflora – on plate count agar. Botulinal toxin was detected using the enzyme-linked immunoassay. Only ten of the products supported the active growth of this pathogen. C. botulinum populations were static in another ten products which had a low pH except for two vegetable-based soups. In the remaining six products, C. botulinum populations reduced to undetectable levels. Although the predictive models described the general growth pattern of C. botulinum in the products supporting the active growth and the products with low pH values, they did not predict the spontaneous decline of this pathogen and the static populations in high pH vegetable soups.

Irradiation of meat, poultry, and other foods helps to preserve food quality and to prevent foodborne disease. This review examines current acceptance and use of irradiated foods in consumer food products and institutional food service applications. In the United States food irradiation is currently used in the space program, in some commercial food applications and in therapeutic diets fed to immunosuppressed patients in health care facilities. In spite of the potential benefits of food irradiation in the United States controversy remains, considerable consumer resistance con-tinues, and adoption of food irradiation for consumer products has been slow des-pite regulatory approval and endorsements by scientific organizations. However, consumer attitudes may be shifting. Experience gathered from the recent uses of irradiation for inactivating anthrax spores in contaminated mail after the terrorist attacks of September 2001 will undoubtedly make irradiation a more familiar process. Possible strategies for improving acceptance are discussed. Consumer education and information about food irradiation are key to greater acceptance.

Food service kitchen oven mitts and potholders are indispensable forms of personal protective equipment (PPE). As mitts and potholders are often contaminated with both raw and cooked food soils that support microbial survival and growth, it has been suggested that they present a possible risk to food safety. To ascertain the extent to which these items might contribute to cross-contamination, 10 dirty oven mitts and 3 dirty potholders obtained from a variety of establishments in the US were surveyed for microbial populations. Aerobic plate counts (APC) as high as 7 × 10⁶ colony forming units (CFU) were found on outer surfaces. Potholders taken from a hospital kitchen were found to have approximately 10⁶ CFU coliforms and B. cereus. Overall, samples examined were seen to have high coliform, B. cereus, and Pseudomonas spp. counts with occasional C. perfringens found. Interior surfaces of mitts, while lower than exterior (geometric mean APC 1.2 × 10⁵ versus 6.0 × 10⁴), were also found to be contaminated with S. aureus. While no E. coli, Listeria spp. or Salmonella spp. were found, indications are that food service PPE offering thermal protection can become contaminated and may, in turn, contaminate hands and food, unless frequently cleaned or sanitized.

Bacteriocinogenic Lactococcus lactis CSCC 146 and Pediococcus pentosaceus ATCC 43200 can be used to improve the safety of extend shelf-life cook-chill foods, however, the information on their growth and bacteriocin production rate at refrigeration temperatures was lacking. These cultures were inoculated at 10⁵–10⁸ cfu/mL in TPGY broth and grown at 10°C. Their populations were enumerated and bacteriocin titre was measured using well diffusion assay. The bacteriocins’ identity produced by L. lactis and P. pentosaceus was confirmed as nisin and pediocin A, respectively, by their enzyme sensitivity pattern. Nisin (>100 IU/mL) was detected between the third and fifth day of storage when the populations of L. lactis reached 10⁸ cfu/mL. Pediocin A (35 AU/mL) was detected on the fourth day when the population of P. pentosaceus reached 10⁹ cfu/mL. Freeze-drying of the cultures did not reduce the speed of the production of bacteriocins. Colour, mouth-feel, texture, flavour and the overall acceptability of commercial sous vide meals was not affected by the presence of the cultures.

A mathematical model using a finite difference method was established to predict the temperature distribution of a microwave-heated food tray. The model was linked with an optimization algorithm to minimize temperature non-uniformity in the microwave-reheating of a cooked rice package. The mathematical model developed was validated by comparing the predicted and measured temperatures, and was used to obtain the optimum heat/hold cycle. Temperature non-uniformity was predicted to increase initially with time and then decrease after the surface corner temperature reached around 100 °C. Minimized temperature non-uniformity was thus attained with the longest heating time, satisfying the highest allowable average temperature under the appropriate number of heat/hold cycles. The control strategy may serve as a useful concept in food service, to improve the heating uniformity of microwaveable dishes.