Sixteen different types of sous vide-processed products were evaluated for safety with respect to nonproteolytic group II Clostridium botulinum by using challenge tests with low (2.0-log-CFU/kg) and high (5.3-log-CFU/ kg) inocula and two currently available predictive microbiological models, Food MicroModel (FMM) and Pathogen Modeling Program (PMP). After thermal processing, the products were stored at 4 and 8°C and examined for the presence of botulinal spores and neurotoxin on the sell-by date and 7 days after the sell-by date. Most of the thermal processes were found to be inadequate for eliminating spores, even in low-inoculum samples. Only 2 of the 16 products were found to be negative for botulinal spores and neurotoxin at both sampling times. Two products at the high inoculum level showed toxigenesis during storage at 8°C, one of them at the sell-by date. The predictions generated by both the FMM thermal death model and the FMM and PMP growth models were found to be inconsistent with the observed results in a majority of the challenges. The inaccurate predictions were caused by the limited number and range of the controlling factors in the models. Based on this study, it was concluded that the safety of sous vide products needs to be carefully evaluated product by product. Time-temperature combinations used in thermal treatments should be reevaluated to increase the efficiency of processing, and the use of additional antibotulinal hurdles, such as biopreservatives, should be assessed.

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Vitamin C contents of pretreated strawberries did not change during 2 mo of freezing, but after jam cooking and storage, the vitamin C contents of all the studied jams decreased dramatically. Jams made from strawberries treated with CaCl 2 and PME in a vacuum had the highest firmness compared to the reference or other pretreated jam strawberries (p , 0.05). According to sensory evaluation of the jams, different prefreezing treatments were shown to have a significant influence on the sensory attributes evaluated (p , 0.001), the only exception being the redness of color after 4 mo storage. EnzymeA liquid enzyme preparation of a microbial pectin methylesterase (PME) from

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BackgroundDietary recommendations for Nordic countries urge the use of plant foods as a basis for healthy nutrition. Currently, the level of dietary fibre (DF) intake is not adequate. Berries are an elementary part of the recommended Nordic healthy diet and could be consumed in higher amounts.Materials and methodsFinnish bilberries and a bilberry press cake from juice processing were studied for DF content, carbohydrate composition, and non-carbohydrate fibre content, which was analysed as sulphuric acid insoluble and soluble material. The microstructure of all samples was also studied using light microscopy and toluidine blue O, calcofluor, and acid fuchsin staining.ResultsThe total DF contents of fresh and freeze-dried bilberries and the press cake were 3.0, 24.1, and 58.9%, respectively. Most of the DF was insoluble. Only about half of it was carbohydrate, the rest being mostly sulphuric acid–insoluble material, waxy cutin from skins, and resilient seeds. Bilberry seeds represented over half of the press cake fraction, and in addition to skin, they were the major DF sources. Microscopy revealed that skins in the press cake were intact and the surface of the seeds had thick-walled cells.ConclusionsBilberry press cake is thus a good source of insoluble non-carbohydrate DF, and could be used to provide DF-rich foods to contribute to versatile intake of DF.