Effects of thermal and nonthermal processing techniques on aroma compounds in fruit juices: A meta‐analysis

Abstract

Aroma compounds play important roles in juice flavor, and how some typical aroma compounds are affected by the processing techniques, in general, has not been unified. Thus, in this study meta‐analysis was used to evaluate the effects of the most widely used thermal (thermal pasteurization and high‐temperature short‐time) and nonthermal processing techniques (high hydrostatic pressure, ultrasound, pulsed electric field, and cold plasma) on four key aroma compounds in fruit juices: d‐limonene, (E)‐2‐hexenal, 1‐hexanol, and 1‐nonanol. Twelve studies were selected according to the set inclusion criteria, and the weighted response ratios (R*) calculated by a random effect model. The study demonstrated that cold plasma (R* = 1.08) and pulsed electric field (R* = 1.17) technique resulted in an increase of d‐limonene levels, and high hydrostatic pressure (R* = 0.95), thermal pasteurization (R* = 0.74), ultrasound (R* = 0.80), and high‐temperature short‐time (R* = 0.77) technique caused a reduction of d‐limonene. The nonthermal techniques can reduce the degradation of the aroma compounds and may induce some chemical reactions to produce more aroma compounds, so that the overall flavor is better maintained than that processed after thermal techniques. This study can help the juice industry to seek processing techniques that can optimize flavor quality.

Effects of Pulsed Electric Field and High-Pressure Processing Treatments on the Juice Yield and Quality of Sea Buckthorn

“…Food processing technology is broadly classified into two types: thermal and non-thermal processing. The most typical way is to sterilize the juice through thermal processing (TP), but TP reduces the juice’s natural nutritional value, appearance quality, and scent flavor owing to the high temperature [ 6 , 7 ]. To solve this issue, non-thermal processing technology substitutes for TP have been identified to maximize consumer demand for excellent nutritional quality and an appealing flavor and look.…”

Thermal and non-thermal pasturization of citrus fruits: a bibliometrics analysis

“…Plasma carotenoids and vitamin C of integrated level are associated with increased intake of fruits which ultimately reduce the possibility of diabetes, cardiovascular diseases, neurological disorders and cancer [ 4 ]. Fruit are popularly known for their refreshing flavor attributes and appealing color with pleasant taste [ 5 ]. Flavor and color were major attributes to determine the acceptability of fruits which are largely dependent of its aroma compounds.…”

“…Thermal pasteurization is highly peculiar to citrus fruits, two out of three mode of heat transfer are applicable to pasteurization of high-moisture fruits-citrus, conduction and convention [ 19 ]. Development in technology of thermal pasteurization has followed a trajectory originated from conventional or traditional thermal process to another generation of microwave heating with improved level of precision, processing time and quality of output [ 5 ]. In addition; sensible heat is attained in the product using steam-controlled condensation which regulate moisture absorption to maintain drying saturated condition of steam [ 14 ].…”

“…Radio frequency (RF) was designed to overcome defect of inadequate depth of heating in microwave and reduce heating rate but at high temperature. It can swiftly change temperature of agricultural produce exponentially and more depth of heat penetration, positive and negative charges of the RF react with proton and neutron in molecules of foods [ 5 , 21 , 22 ]. The global acceptance of RF in food processing industry is a function of its potentials to reduce nutrient losses, reduced heating duration and increased scale of production.…”