Theoretical analysis of secondary shelf life: Interactive relationship with package opening time and food quality degradation rate shift

• Published in: Food packaging and shelf life Vol. 41; p. 101238
• Main Author: Lee, Dong Sun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2024
• Subjects: Critical limit; Moisture; Oxidation; Primary shelf life; Quality deterioration kinetics; Critical limit; Primary shelf life; Oxidation; Quality deterioration kinetics; Moisture
• ISSN: 2214-2894; 2214-2894
• DOI: 10.1016/j.fpsl.2024.101238

Simple dimensionless formula was mathematically derived to relate secondary shelf life (SSL) of packaged foods to package opening time (POT) and food quality deterioration rate shift (k2/k1) thereafter. Their primary shelf life (PSL) was assumed to be time period to reach a critical limit of acceptability in the intact packaged state. A formula universally applicable for first order, zero order, exponential autoxidation and moisture permeation kinetics could be formulated: SSL/PSL=(1-POT/PSL)/(k2/k1). The model formula was verified by mathematical simulation for typical conditions of kinetic parameters and quality limits. Its implication and limitation were discussed in perspective of practical applicability keeping in mind the supposed hypotheses. Overview on the nature of SSL as function of POT and k2/k1 shows that the latter influences SSL dominantly, and keeping it low after package opening, desirably below 5, is essential to ensure substantially long SSL. The formulated model can be useful to provide guideline of package opening and SSL in shelf life management including marketing and consumer use of the packaged foods. •Simple formula relating secondary shelf life (SSL) to package opening time (POT) was set up.•POT before primary shelf life (PSL) combined with SSL to reach critical quality limit.•First order, zero order, autoxidation and moisture permeation as food deterioration kinetics.•The formula: SSL/PSL=(1-POT/PSL)/(k2/k1), where k2/k1 is rate shift.•Rate constant shift governs length of SSL over the practical range for shelf-stable foods.