Purpose: Thus, the objective of this study was to summarize all published findings on the heat resistance of AAT, and to explain the differences among the D- and z-values by assessing study characteristics such as type of beverage (juice, concentrate), application of clarification, use of bacteriocins and fruit type.
Methods: The Bigelow secondary predictive model was used to interpret the combined results of the primary studies. As the meta-analytical data encompassed a number of coded study characteristics, the basic Bigelow model was transformed into a linear mixed-effects model in order to assess whether each of the moderating variables had any effect on D and z.
Results: The meta-analysis demonstrated that the heat sensitivity of AAT had on average log D* (log D at 95°C and pH 3.5) values higher than juices by 0.115 units (P < 0.01), while the z-values were higher (P < 0.01) in concentrates than in juices. AAT possesses lower thermal resistance in clarified beverages than in non-clarified beverages (P < 0.01), with log D* higher by 0.26 units, while clarification did not affect z-values. In addition, the effect of a bacteriocin on the thermal sensitivity of AAT became more evident at higher pH.
Significance: Because of its design, the meta-analysis model is able to provide D and z estimates for single-strength juices and concentrates of ten different fruits, with or without clarification and, with or without bacteriocins.