Size and shape attributes of packaging remnants commonly detected in former food products

Abstract

Former food products (FFPs) are alternative feed ingredients used in livestock diets. Although the processes of transforming FFPs into animal feed often include mechanical unpacking and grinding, the final products may still be prone to packaging contamination. Common materials of packaging remnants found in FFPs are aluminium, cellulose, and plastic. Therefore, it is important to investigate and to provide information regarding the size and shape attributes of these materials to improve processing techniques in the feed industry. A total of 441 packaging remnants from 17 sources of FFPs were included in this study. Fourier transform infra-red spectroscopy coupled with an optical microscope was used to identify the material of the packaging remnants, which resulted in a categorisation of remnants consisting of 44 aluminium, 308 cellulose, and 89 plastic remnants. The categorised remnants were observed with a stereomicroscope and were subsequently measured by a digital camera and image analysis software. Each measurement contains 21 size attributes and 9 shape attributes, some of which were derived from calculations. The distribution of values for both size and shape attributes overlapped between the three materials though aluminium remnants were on average smaller (p < .05) in size and more regular (p < .05) in shape compared to cellulose and plastic ones. Also, aluminium remnants showed a narrower range in most of the size and shape attributes. Through the information provided by the image analysis and the measurements, it was concluded that the obtained values in size and shape attributes had broadly spread distributions that overlapped for different materials.

HIGHLIGHTS

• Former food products are slightly contaminated with packaging remnants.

• Aluminium, cellulose, and plastic are packaging materials commonly detected as remnants in former food products.

• Aluminium remnants were on average smaller and more regular in shape whereas cellulose remnants were likely to have irregular edges and stellular shapes.

• The obtained values in size and shape attributes of FFP packaging remnants had broadly spread distributions overlapping for different materials.

Keywords:

• Former food products
• packaging remnants
• feed safety
• feed contamination, stereomicroscope

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data used for this study are available from corresponding author upon reasonable request.

Additional information

Funding

The present work was carried out in the framework of the following projects: Agritech National Research Center was funded by the European Union Next-Generation EU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR)–MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4–D.D. 1032 17/06/2022, CN00000022). This manuscript reflects only the authors’ views and opinions, neither the European Union nor the European Commission can be considered responsible for them; ASSO 14 project was funded by Regione Lombardia; Determinazione delle microplastiche nei mangimi contenenti ex prodotti alimentari” Ricerca Corrente ministero Salute, IZSPLV.