Shelf life extension of pre-baked buns by an ACTIVE PACKAGING ethanol emitter

Abstract

The paper reports the influence of an ethanol emitter (Ethicap) on the microbiological condition and the shelf life extension of a bakery product. Pre-baked buns, with a water activity of 0.95, were packaged with different amounts of Ethicap and stored at room temperature. Yeasts and moulds remained largely absent from the core of the pre-baked bun (< 10(2) cfu g(-1)) during storage, independent of the presence of ethanol. The total mesophilic count was low at the beginning of the storage experiment (< 10(2) cfu g(-1)), but increased without ethanol within 1 week to an unacceptable level. In the presence of ethanol, the total mesophilic count stabilizes at a consumable level of 10(5)-10(6) cfu g(-1). The increase of total mesophilic count was caused by growth of a Bacillus spp., probably B. subtilis. Mould growth on the outer surface is limiting for shelf life extension. On the pre-baked buns, the following moulds were present: Penicillium solitum, P. commune, P. corylophilum, Cladosporium sphaerospermum and C. herbarum. These started to grow within 4-6 days. Mould growth can be delayed for 13 days by adding Ethicap. The ethanol probably has to be absorbed by the pre-baked bun to be effective in growth suppression of the Bacillus spp. the moulds. The pre-baked buns absorb most of the ethanol from the package headspace, and the ethanol content of the products is approximately 0.8 weight% after 21 days. This largely exceeds the overall migration limit of 60 mg kg(-1) food (0.006 weight%).

Strategies to Extend Bread and GF Bread Shelf-Life: From Sourdough to Antimicrobial Active Packaging and Nanotechnology

“…Ethicap ® has several advantages: (i) ethanol vapor can be generated without spraying ethanol solutions directly onto products prior to packaging; (ii) sachets can be conveniently removed from packages and discarded at the end of the storage period; (iii) low cost. Franke and colleagues (2002) [56] also reported the use of Ethicap ® in pre-baked buns (a w = 0.95) packaging. They found that packaging into gamma sterile PE-LD bags with Ethicap ® delayed mould growth for 13 days, at room temperature.…”

“…Nanocomposites have also improved barrier ability against oxygen, carbon dioxide, ultraviolet radiation, moisture and volatiles. In addition, they may (i) let air and other enzymes out but not in, (ii) degrade ripening gas, such as ethylene, and (iii) have antimicrobial activity [56,[58][59][60][61][62][63]. Hence, nanocomposites may be used to extend food shelf-life, thus reducing the addition of man-made preservatives in foods.…”

Control of food spoilage fungi by ethanol

“…This ethanol emitter extended the shelf-life of packaged apple turnovers (Smith et al, 1987), pita bread (Black, Quail, Reyes, Kuzyk, & Ruddick, 1993), packed sliced rye bread (Salminen et al, 1996), English-style crumpets (Daifas et al, 2003) and pre-baked buns (Franke, Wijma, & Bouma, 2002). The effects of ethanol on a complex mycoflora were difficult to assess because the ethanol in the headspace was not constant throughout the experiments.…”

Effect of colloidal properties of oil-in-water emulsions on ethanol liquid–vapour partition

“…In particular, flavour, which is considered one of the most important attributes determining the acceptability of food to the consumer, depends on the nature and concentration of aroma compounds, whose molecules are characterised by a sufficiently high vapour pressure to be present in the gas phase (Landy, Courthaudon, Dubois, & Voilley, 1996). On the other hand, in these last years, the effect of some volatile compounds present in the headspace of a packed food on the inhibition of the growth of some pathogenic microorganisms and fungi has been evidenced (Corbo, Lanciotti, Gardini, Sinigaglia, & Guerzoni, 2000;Franke, Wijma, & Bouma, 2002 The concentration of the free volatile compounds in the gas phase depends on their physico-chemical properties, concentration in the liquid and/or solid phase as well as their interactions with the other constituents of the food matrix (Draux & Voilley, 1997). The liquid-vapour partition has been generally studied in simple mixtures, i.e., model system consisting of water, a volatile substance and a non-volatile constituent, in order to better elucidate the specific interactions between the different components and the correspondent effects on the aroma release.…”