Sterilization of Milk and Other Products

Hinrichs, Jörg; Wedel, Carolin; Atamer, Zeynep

doi:10.1016/b978-0-08-100596-5.22681-4

Cited by 2 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bradshaw et al [ 75 ] isolated a B. cereus strain that had a D 121.1 -value of 0.03 min (1.8 s) and a z -value of 7.9 °C, and commented that these D - and z -values were similar to those most commonly reported for B. cereus . This approximately agrees with van Asselt and Zweitering [ 77 ]: the mean D 120 -value of B. cereus spores of 0.041 min (2.46 s), (their upper 95% prediction interval D 120 -value was 0.52 min or 31.2 s) and a D 121 reference value given by Hinricks and Atamer [ 78 ] (p. 716), of 0.04 min (2.4 s).…”

Section: Microbiological Considerationssupporting

confidence: 89%

“…The slope of the line is based on the assumption that the z -value for psychrotrophic spore inactivation is the same as for inactivation of thermophilic spores, i.e., ~10. This is a reasonable assumption given the wide range of z -values reported for B. cereus spores [ 66 , 74 , 76 , 77 , 78 ]. It is therefore proposed that the B * for ESL processing should be >0.3.…”

Section: Optimizing Esl Heating Conditionsmentioning

confidence: 89%

“…The range of reported z -values for B. cereus spores is 6.7–13.8 °C, with most in the range of 8–11 °C [ 66 , 74 , 76 , 77 ]. Hinricks and Atamer [ 78 ] (p. 716) cite the z -value for a reference strain as 9.4–9.7 °C, which is in the middle range of reported values.…”

Section: Microbiological Considerationsmentioning

confidence: 99%

“…However, some authors have used reported D - and z -values to construct temperature–time semi-log curves of equal destruction of B. cereus spores. For example, van Asselt and Te Giffel [ 79 ] and de Jong et al [ 11 ] constructed lines for a 6-log reduction, while Hinrichs and Atamer [ 78 ] constructed a 3-log reduction line. However, based on the information above, the appropriate lines for destruction of individual strains will vary considerably in both position, according to their D -values, and slope, according to their z -values.…”

Section: Microbiological Considerationsmentioning

confidence: 99%

“…Published graphs should therefore be used as a guide to temperature–time combinations to use in processing but should not be assumed to apply to all strains of B. cereus . Interestingly, the D 121 -value estimated from the graphs of de Jong et al [ 11 ] and van Asselt and Te Giffel [ 79 ] is ~0.03 s (that is, 1/6 of the 6-D of ~2 s read from the graphs) and from the graph of Hinrichs and Atamer [ 78 ] is ~0.14 s (that is, 1/3 of the 3-D of ~4.2 s read from the graph). These values however, differ considerably from those recorded, above, namely, 0.03–0.04 (1.8–2.4 s) (excluding data for very heat-tolerant strains).…”

Section: Microbiological Considerationsmentioning

confidence: 99%

See 4 more Smart Citations

Optimum Thermal Processing for Extended Shelf-Life (ESL) Milk

Deeth

2017

Foods

View full text Add to dashboard Cite

Extended shelf-life (ESL) or ultra-pasteurized milk is produced by thermal processing using conditions between those used for traditional high-temperature, short-time (HTST) pasteurization and those used for ultra-high-temperature (UHT) sterilization. It should have a refrigerated shelf-life of more than 30 days. To achieve this, the thermal processing has to be quite intense. The challenge is to produce a product that has high bacteriological quality and safety but also very good organoleptic characteristics. Hence the two major aims in producing ESL milk are to inactivate all vegetative bacteria and spores of psychrotrophic bacteria, and to cause minimal chemical change that can result in cooked flavor development. The first aim is focused on inactivation of spores of psychrotrophic bacteria, especially Bacillus cereus because some strains of this organism are pathogenic, some can grow at ≤7 °C and cause spoilage of milk, and the spores of some strains are very heat-resistant. The second aim is minimizing denaturation of β-lactoglobulin (β-Lg) as the extent of denaturation is strongly correlated with the production of volatile sulfur compounds that cause cooked flavor. It is proposed that the heating should have a bactericidal effect, B* (inactivation of thermophilic spores), of >0.3 and cause ≤50% denaturation of β-Lg. This can be best achieved by heating at high temperature for a short holding time using direct heating, and aseptically packaging the product.

show abstract

Section: Microbiological Considerationssupporting

confidence: 89%