Milk spoilage model predicts that share tables do not cause a meaningful increase in spoilage and that storage systems can be implemented to mitigate it in long lunch services

School share tables offer opportunities for food recovery and increased access by allowing students to return unopened items. However, stakeholders have concerns regarding the potential temperature abuse and premature spoilage share tables may cause, especially in milk. While research has shown that the addition of short, ambient temperature abuse of milk, representing share tables, does not meaningfully impact microbial milk quality, differences in school-to-school cafeterias (ambient temperatures, storage systems, bell schedules, refrigeration temperature, milk initial microbial quality) may limit this conclusion. To address this, (i) milk temperature data for refrigeration and typical share table storage systems were collected to (ii) inform and validate heat transfer models capable of predicting milk temperature under potential ST scenarios, and (iii) use a previously published process model for school cafeteria STs to determine if psychrotolerant bacteria in milk would reach a spoilage threshold (6.0 log(CFU/ml)) as a factor of the milk residence time in the cafeteria system and its temperature profile. The overnight refrigeration temperature and the milk’s initial contamination were predicted to be the main drivers for milk spoilage. Share tables were predicted to not cause meaningful microbial quality changes under short and medium bell schedules (≤125 minutes of total service), even with ambient temperature storage during the service (≤ 2 milk spoiled per year). Under long (221 minutes) and very long (266 min) bell schedules, ambient temperature storage was predicted to have higher milk spoilage (≤ 6 milk spoiled per year), and adding storage systems was predicted to reduce the decline in milk quality (≤ 3 milk spoiled per year). These results provide a resource to support science-based decision-making for the inclusion of milk in school cafeteria share tables, ultimately working to reduce food waste and improve food security.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Food Science & Human Nutrition

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Corea Ventura, Paola

Contributors dc:contributor

• Stasiewicz, Matthew J
• Miller, Michael
• Cadwallader, Keith

• Food Recovery
• Food Waste
• Milk Spoilage
• Share Tables

Statement dc:rights

• Copyright 2024 Paola Corea Ventura

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/124656

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F124656