The detection and quantification of food components on stainless steel surfaces following use in an operational bakery

Abstract

Food preparation areas in commercial bakeries present surfaces for continual organic fouling. The detection of retained food components and microorganisms on stainless steel surfaces situated for one month in the weighing in area, pastry and confectionary production areas of a bakery were investigated using different methods. Scanning electron microscopy demonstrated the morphology of the material on the surfaces from all three areas, with the weighing in area demonstrating a more even coverage of material. Differential staining assays demonstrated a high percentage coverage of organic material heterogeneously distributed across the surfaces. Differential staining also demonstrated that the amount of organic material on the surface from the confectionary area was significantly greater than from both the pastry and weighing in areas. Although, UV at 353 nm did not detect residual surface fouling, performance of the UV detection was optimised and demonstrated that the residual organic material on the weighing in area and the pastry samples was best illuminated at 510-560 nm, and from the confectionary area of the bakery at 590-650 nm. ATP bioluminescence revealed the confectionary production area contained the highest level of biofouling. Contact plates determined that only low microbial counts (≤ 2) CFU/cm 2) were recovered from the surfaces. Changes in the physicochemistry (increased hydrophobicity) demonstrated that all the surfaces were fouled (ΔGiwi-26.8 mJ/m 2 to-45.4 mJ/m 2). Fourier Transform Infra-Red Spectroscopy (FTIR) demonstrated that all the surfaces had retained fats,

Microbial Biofilms in the Food Industry—A Comprehensive Review

“…As with other previously mentioned techniques, SEM is a widely used resource for confirming the presence of bacteria and the exopolysaccharide matrix when studying biofilms ( Figure 9 , Figure 10 and Figure 11 ). These studies usually obtain SEM results and are supplemented with the results of other techniques like confocal [ 208 , 209 ], surface-enhanced Raman scattering (SERS) spectroscopy [ 210 ], epifluorescence microscopy (DAPI/Rhodamine B), and contact plates [ 211 ].…”

Food safety: Cleanliness and disinfection of food contact surfaces in gastronomy laboratories at a university in Colombia

“…The result of the ATP-bioluminescence assay was expressed in relative light units (RLU/100 cm 2 ). According to the manufacturer of <10 RLU/100 cm 2 the surface could be considered clean, ≥10 to ≤29 RLU/100 cm 2 , indicated that the surface was not adequately clean, and >30 RLU/100 cm 2 the surface required cleaning (Whitehead et al, 2019).…”

Development of a novel cryostructured composite coating of xanthan–bovine collagen–oregano essential oil spraying applied for the preservation of commercial biscuits marketed in Mexico

“…The growing popularity of bakery products based on the addition of diverse active ingredients is one of the key factors driving the growth of this industry sector; as biscuits are products consumed by a large segment of the population and offer a wide margin for the incorporation of nutritional or functional ingredients (Whitehead et al, 2019). Salehi (2019Salehi ( , 2020aSalehi ( , 2020b mentioned the importance of the use of different hydrocolloids or gums, either as coatings or as part of the composition of bakery products, with the aim of improving the physicochemical and textural characteristics of this type of food, maintaining or increasing its ability to bind and/or hold water.…”

“…The growing popularity of bakery products based on the addition of diverse active ingredients is one of the key factors driving the growth of this industry sector; as biscuits are products consumed by a large segment of the population and offer a wide margin for the incorporation of nutritional or functional ingredients (Whitehead et al., 2019).…”