Viability of sous vide, microwave and high pressure processing techniques on quality changes during shelf life of fresh cowpea puree.

An innovative cowpea puree containing 78.8% of fresh cowpea seeds was developed. Microwave treatment (8 kW/35 s), high hydrostatic pressure (550 MPa/10 min/23 ℃) or sous vide treatment (80 ℃, 3 min) were assayed as processing techniques. Blended fresh cowpea samples were used as control. Quality changes during 21 days at 5 ℃ were studied. Sous vide samples showed a relevant loss during storage of viscoelastic parameters, like elastic modulus (G') and viscous modulus (G″), which was also perceived in the sensory evaluation. On the contrary, high hydrostatic pressure and microwave treatments were able to preserve consistency, texture and taste. However, physicochemical properties, mainly colour, were greatly influenced by thermal treatments, although high hydrostatic pressure treatment preserved greenness. Total phenolic content and total antioxidant capacity were more affected by high hydrostatic pressure than by microwave treatments. In conclusion, microwave and high hydrostatic pressure processing treatments seem to be quite interesting techniques to develop legume-based products.

UV-C pretreatment of fresh-cut faba beans (Vicia faba) for shelf life extension: Effects of domestic microwaving for consumption.

Faba beans have a short shelf life which is even reduced after fresh-cut processing mainly due to browning and dehydration. In that sense, the effects of a UV-C treatment (3 kJ m-2), compared with non-exposed beans (CTRL), were studied on the sensory and microbial quality, and bioactive and anti-nutritional content of fresh-cut faba beans (cv. Muchamiel) during storage at 5 ℃. The effect of a domestic microwaving (3 min, 900 W) on bioactive and anti-nutritional compounds of fresh seeds prior to consumption at each sampling time was also studied. UV-C treatment extended the fresh-cut faba bean shelf life from 7 to 10 days with browning score (the main sensory parameter adversely affected) of 8 and 1 log unit lower than CTRL at day 10. UV-C did not negatively affect the total antioxidant capacity of samples during storage. The phytic acid and raffinose contents decreased by 30/40%, respectively, after 10 days, without influence of the UV-C treatment. Microwaving reduced the phytic acid and condensed tannins contents by 30% in those samples stored for up to six days, with low microwaving effect in the last storage days. Nevertheless, UV-C improved the condensed tannins reductions through storage (≈30%) compared with non-irradiated samples.

Effects of α-, ß- and maltosyl-ß-cyclodextrins use on the glucoraphanin-sulforaphane system of broccoli juice.

Cyclodextrins (CDs) are macromolecules with several industrial applications, being particularly used in the food industry as health-promoting compounds protection agents, as flavour stabilizers, or to eliminate undesired tastes and browning reactions, among others. This study shows the effects of α- (10, 30 and 40 mmol L-1 ), ß- (3, 6 and 10 mmol L-1 ) and maltosyl-ß-CDs (30, 60 and 90 mmol L-1 ) use on the health-promoting glucoraphanin-sulforaphane system of a broccoli juice up to 24 h at 22 °C. Maltosyl-ß-CD (90 mmol L-1 ) highly retained glucoraphanin content after 24 h at 22 °C, showing better effectiveness than ß-CD (10 mmol L-1 ). Sulforaphane was efficiently encapsulated with ß-CD at just 3 mmol L-1 , and the sulforaphane formed was stable during 3 h at 22 °C. On the other hand, 40 mmol L-1 α-CD retained a high glucoraphanin content in broccoli juice. In contrast, glucoraphanin levels in juice without CDs decreased by 71% after 24 h. Consequently, CDs addition may potentially preserve glucoraphanin in this broccoli juice during industrial processing with the possibility to be later transformed by endogenous myrosinase after ingestion to the health-promoting sulforaphane. © 2018 Society of Chemical Industry.

Immature pea seeds: effect of storage under modified atmosphere packaging and sanitation with acidified sodium chlorite.

BACKGROUND: Appropriate sanitation is a priority for extending the shelf life and promoting the consumption of immature pea seeds, as processing accelerates quality deterioration and microbial growth. RESULTS: The combined effect of disinfection with acidified sodium chlorite (ASC) or sodium hypochlorite (SH) and packaging under a passive modified atmosphere (MAP) at 1 or 4 °C on quality was analysed. After 14 days, greenness and vitamin C had decreased, especially in the SH-disinfected samples. Total phenols and antioxidant capacity were not affected by disinfection. Proteins levels fell by around 27%, regardless of the sanitizer and storage temperature. Compared with the initial microbial load, samples stored at 1 °C showed an increase of 1 log CFU g-1 in psychrophiles when treated with SH, whereas no increase of note occurred with ASC. In general, microbial counts were always below 3 log CFU g-1 for all the treatments. CONCLUSION: Immature pea seeds could be stored for 14 days at 1-4 °C under MAP with only minor quality changes. Disinfection with ASC resulted in better sensory quality, higher content of vitamin C and lower psychrophile counts. More research is needed to analyse the effect of these treatments on other quality parameters. © 2017 Society of Chemical Industry.