Quality Characteristics and Shelf-Life of Ultra-High Pressure Homogenized (UHPH) Almond Beverage

Abstract

The effects of ultra-high-pressure homogenization (UHPH) at 200 MPa, in combination with different inlet temperatures (55 or 75 °C) during storage at 4 °C were studied and compared with pasteurized (90 °C, 90 s) almond beverage. Microbiological analysis of the physical (particle sedimentation and color) and volatile profile of the most relevant compound in almond beverages was performed at days 1, 7, 14, and 21 of cold storage. UHPH treatment 200 at 75 °C led to higher microbiological reduction after treatment and higher stability during cold storage in almond beverages than pasteurization or UHPH 200 at 55 °C. Physical characteristics of UHPH-treated samples exhibited a high stability during storage with a stable color. Volatile compounds extracted by solid-phase microextraction were identified by gas chromatography coupled with mass spectrometry. The effect of UHPH treatment significantly (p < 0.05) affected the volatile profile compared with pasteurized beverages, although UHPH conditions applied produced similar effects in almond beverages. Benzaldehyde was the most abundant compound detected in all treatments. Hexanal was more abundant in UHPH-treated samples, indicating a higher lipid oxidation compared to pasteurized almond beverages.

Physicochemical and microstructural properties and probiotic survivability of symbiotic almond yogurt alternative using polymerized whey protein as a gelation agent

“…As a consequence, commercial almond‐based yogurt alternative has different functionalities compared to its dairy counterpart, especially in the manufacturing processes, such as heating treatments, the choices of stabilizers, the composition of starter cultures, and fermentation conditions (Day, 2013). Several studies tried to improve textural qualities and extend the shelf life of almond milk through the treatment of ultra‐high pressure homogenization (Ferragut, Valencia‐Flores, Pérez‐González, Gallardo, & Hernández‐Herrero, 2015; Toro‐Funes, Bosch‐Fusté, Veciana‐Nogués, & Vidal‐Carou, 2014). However, because of the low protein content in almond milk, it is still necessary to add emulsifying agents (like lecithin) in homogenized almond milk to keep physically stable in storage (Toro‐Funes et al, 2014).…”

Effects of pressure and multiple passes on the physicochemical and microbial characteristics of lupin‐based beverage treated with high‐pressure homogenization

“…To completely inactivate spores, a very high pressure and temperature should be applied, and the inlet temperature during HPH treatment must be higher than 75°C under 200 MPa or 55°C under 200 MPa (Valencia‐Flores et al, ). B. cereus , a type of Gram‐positive bacteria, also showed an extremely high resistance to HPH treatment, and at least 200‐MPa pressure at 55°C inlet temperature must be applied to completely inactivate this kind of bacteria (Ferragut, Valencia‐Flores, Pérez‐González, Gallardo, & Hernández‐Herrero, ).…”

“…The characteristics of fat droplet markedly influence the color of beverages. The L* value of an emulsion is associated with the efficiency of the dispersion of droplets, which in turn is associated with the size and concentration of particles in the emulsion (Ferragut et al, ). With a fixed number of HPH treatment pass, the increase of the pressure could induce an increase of the L* value.…”

Physicochemical and microstructural properties of fermentation-induced almond emulsion-filled gels with varying concentrations of protein, fat and sugar contents

“…The changes in lightness are related to the amount of protein and fat contents as the protein aggregation level and the particle size (e.g. protein particles, fat globules and fat and protein clusters) influence the light scattering of products, which is related to their ability to reflect light ( Ferragut et al, 2015 ). This finding is supported by the particle size results in Table 3 .…”