Heat resistance and the effects of continuous pasteurization on the inactivation ofByssochlamys fulvaascospores in clarified apple juice

Abstract

Aims: To determine thermal resistance, the effect of pasteurization temperature variations (c. 2°C) in a continuous system in the number of decimal reductions (n) of a Byssochlamys strain in clarified apple juice (CAJ). Methods and Results: Thermal destruction kinetics of Byssochlamys fulva IOC 4518 in thermal death tubes were determined at 85°, 90°, 92° and 95°C by using Weibull distribution frequency model. Three processes with different heating and holding temperatures (A: 94°, 92°C; B: 95°, 93°C; C: 96°, 94°C, respectively) were performed in a continuous system. Process time was 30 s. δ (time of first decimal reduction) values were: 42·98, 8·10, 3·62 and 1·81 min. Variable n ranged from 0·16 to >4·78 for process B (equivalent to industrial). Variable n (0·95–2·66 log CFU ml−1) were obtained in CAJ bottles processed under condition B, while process A resulted in total heat‐resistant mould (HRM) survival and process C in total HRM destruction. Conclusions: This study demonstrates that small variations in temperature during the CAJ pasteurization could result in elimination or survival of HRM due to its nonlogarithmic behaviour. Significance and Impact of the Study: This was the first study to use Weibull frequency method to model inactivation of HRM in fruit juices. Temperature variations could culminate in the presence of HRM in pasteurized juices even when low counts (<10 spores per 100 ml) were present in the raw materials.

Inactivation of Neosartorya fischeri and Paecilomyces variotii on paperboard packaging material by hydrogen peroxide and heat

“…Mold spore suspensions were prepared as previously described (Delgado et al, 2000;Sant'Ana et al, 2009). It is known that age of spores influence molds' responses to activation or inactivation treatments as well their growth parameters (Blaszyk & Holley, 1998;Judet, Bensoussan, Perrier-Cornet, & Dantigny, 2008;Slongo & Aragão, 2006;Zimmermann, Miorelli, Massaguer, & Aragão, 2010).…”

“…Some studies report on the inactivation of bacterial spores by hydrogen peroxide (Hilgren et al, 2009;Podolak et al, 2009;Xu et al, 2008), however, to the authors' best knowledge there is no research that regards the inactivation of heat resistant molds that may contaminate paperboard materials used in the aseptic processing. Heat-resistant molds such as Byssochlamys, Neosartorya, Talaromyces, Eupenicillium and anamorph with asexual spores such as Paecilomyces are well-known because of their high heat and chemical resistances (Salomão, Massaguer, & Aragão, 2008;Sant'Ana, Rosenthal, & Massaguer, 2009;Tournas, 1994;Tribst, Franchi, Cristianini, & Massaguer, 2009), involvement in food spoilage (Beuchat & Pitt, 2001;Tribst et al, 2009) and ability to produce mycotoxins (Beuchat & Pitt, 2001;Sant'Ana et al, 2010). These microorganisms are largely found in the soil (Beuchat & Pitt, 2001) and may be carried to food processing plants by dust and fruit surfaces (Beuchat & Pitt, 2001) resulting also in the contamination of packaging materials and foods.…”

Influence of Different Filling, Cooling, and Storage Conditions on the Growth of Alicyclobacillus acidoterrestris CRA7152 in Orange Juice

“…Thermocouples were located at the end of the preheating, holding, cooling, SPO, and cooling (by water spraying) units, and the temperature was recorded every 10 s. In addition, two pressure sensors were installed, the first at the preheater and the second at the cooler. A schematic figure of the Microthermics equipment used can be seen in Sant'Ana et al (22).…”

“…Of these, A. acidoterrestris is considered the most important spoilage species within the Alicyclobacillus genus either by its frequency of occurrence or by its linkage to the spoilage problems of fruit juices and beverages. The broad temperature range for A. acidoterrestris growth (25 to 60°C) (33,21,20,30,11), its ability to grow under acidic environments (pH 2.5 to 6.0) (20,30,19,22,6), and its high heat resistance in orange juice (D at 95°C of 2.7 min) (8) together provide adequate conditions for both survival through pasteurization and growth during juice storage.…”

MODELAGEM MATEMÁTICA DO CRESCIMENTO DE Byssochlamys fulva EM SUCO DE MAÇÃ SOLIDIFICADO SOB CONDIÇÕES NÃO–ISOTÉRMICAS, UTILIZANDO MEDIDAS DO DIÂMETRO DA COLÔNIA E DO CONTEÚDO DE ERGOSTEROL

“…Espécies como Byssochlamys, comumente encontrados em produtos de frutas, são descritos como produtores de micotoxinas (Sant'Ana et al, 2009). …”