Extension of the shelf-life of fresh pasta using modified atmosphere packaging and bioprotective cultures

Abstract

Microbial stability of fresh pasta depends on heat treatment, storage temperature, proper preservatives, and atmosphere packaging. This study aimed at improving the microbial quality, safety, and shelf life of fresh pasta using modified atmosphere composition and packaging with or without the addition of bioprotective cultures (Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium spp., and Bacillus coagulans) into semolina. Three fresh pasta variants were made using (i) the traditional protocol (control), MAP (20:80 CO₂:N₂), and barrier packaging, (ii) the experimental MAP (40:60 CO₂:N₂) and barrier packaging, and (iii) the experimental MAP, barrier packaging, and bioprotective cultures. Their effects on physicochemical properties (i.e., content on macro elements, water activity, headspace O₂, CO₂ concentrations, and mycotoxins), microbiological patterns, protein, and volatile organic compounds (VOC) were investigated at the beginning and the end of the actual or extended shelf-life through traditional and multi-omics approaches. We showed that the gas composition and properties of the packaging material tested in the experimental MAP system, with or without bioprotective cultures, positively affect features of fresh pasta avoiding changes in their main chemical properties, allowing for a storage longer than 120 days under refrigerated conditions. These results support that, although bioprotective cultures were not all able to grow in tested conditions, they can control the spoilage and the associated food-borne microbiota in fresh pasta during storage by their antimicrobials and/or fermentation products synergically. The VOC profiling, based on gas-chromatography mass-spectrometry (GC-MS), highlighted significant differences affected by the different manufacturing and packaging of samples. Therefore, the use of the proposed MAP system and the addition of bioprotective cultures can be considered an industrial helpful strategy to reduce the quality loss during refrigerated storage and to increase the shelf life of fresh pasta for additional 30 days by allowing the economic and environmental benefits spurring innovation in existing production models.

Keywords: bioprotective cultures; fresh pasta; metagenomics; modified atmosphere packaging; multi-omics approach; shelf-life.

FIGURE 1

Schematic design showing the production of fresh pasta at the semi-industrial factory and the analyses performed.

FIGURE 2

Bacterial community composition at phylum (A) and genus (B) level for fresh pasta samples by 16S rRNA gene V5–V6 region sequencing. 1MA, control fresh pasta obtained by protocol and packaging MAP conditions used at plant level analyzed at the beginning and the end of the actual 90 days of shelf life (1MA-T0, 1MA-T90); 2MA, fresh pasta obtained by conventional protocol and packaged in experimental MAP conditions analyzed at the beginning and the end of the actual and expected 90, 110, and 120 days of shelf life (2MA-T0, 2MA-T90, 2MA-T110, 2MA-T120); 2MA-BC, fresh pasta obtained by the addition of bioprotective culture onto semolina and packaged in experimental MAP conditions, analyzed at the beginning and the end of the actual and expected 90, 110, or 120 days of shelf life (2MA-BC-T0, 2MA-BC-T90, 2MA-BC-T110, 2MA-BC-T120).

FIGURE 3

Fungi microbiota (yeasts and molds) composition in fresh pasta samples by ITS1 region sequencing. 1MA, control fresh pasta obtained by protocol and packaging MAP conditions used at plant level analyzed at the beginning and the end of the actual 90 days of shelf life (1MA-T0, 1MA-T90). (A) Fungal genera with a relative abundance >0.1% in at least one sample. To note, the scale values started from 90% due to the relative abundance of Wickerhamomyces that was >91%. (B) Heatmap based on relative abundance (normalized for row) of the top 20 abundant fungal species. Colors correspond to normalized mean data levels from low (green) to high (red).

FIGURE 4

Principal component analysis (PCA) of 24 volatile organic compounds that significantly differed (p < 0.05; one-way ANOVA) between fresh pasta samples. ▲, 1MA, control fresh pasta obtained by conventional protocol and packaging MAP conditions used at the plant level; □, 2MA, fresh pasta obtained by conventional protocol and packaged in experimental MAP conditions; ⋄, 2MA-BC, fresh pasta obtained by the addition of bioprotective culture onto semolina and packaged in experimental MAP conditions. Three biological replicates were analyzed at the beginning (0 days, green color) and the end (blue color) of the actual 90 days of storage.