Preliminary Evaluation of a Novel Microwave-Assisted Induction Heating (MAIH) System on White Shrimp Cooking

Abstract

The microwave-assisted induction heating (MAIH) system provides comprehensive heating by combining microwave heating (with 1300 W of power and 2450 MHz of frequency) in the top part and induction heating (with 1800 W of power) in the bottom part. In this study, fresh white shrimps were placed in a sealed crystallized polyethylene terephthalate (CPET) container and heated in the MAIH system at two temperatures (130 and 90 °C) from 60 to 120 s. Afterwards, the shrimp samples were rapidly cooled, and the changes in the shrimp quality, including the appearance, cook loss, aerobic plate count (APC), color values, and texture, during the heating process were analyzed. The results demonstrate that longer heating times decrease the APC levels, but increase the cook loss, color values (lightness, redness, and whiteness), and texture (hardness, cohesiveness and chewiness) of the white shrimp samples. In particular, the white shrimp is fully cooked and gains a completely red appearance, along with no APC detected after heating in the MAIH system at 130 °C for at least 80 s or at 90 °C for at least 100 s. In summary, to achieve a good appearance, no APC detected, and low cook loss, the following heating conditions are recommended for cooking white shrimp in the MAIH system: heating at 130 °C for 80 s or at 90 °C for 100 s. This novel MAIH technology allows food to be heated and sterilized after being packed, thereby eliminating the post-pollution issue. To the best of the authors’ knowledge, this is the first study to evaluate the use of MAIH in the application of food processing.

Effect of a Novel Microwave-Assisted Induction Heating (MAIH) Technology on the Quality of Prepackaged Asian Hard Clam (Meretrix lusoria)

“…APC and PBC are both important indexes for evaluating the quality of fresh and low-temperature-stored aquatic products. A similar finding was previously demonstrated by Lee et al [11], who found that MAIH at 130 • C for 80 s or 90 • C for 100 s significantly reduced the APC level of white shrimp to become negligible (<2.0 log CFU/g). Regarding the HBC and coliform counts, the raw hard clam had an initial HBC of 3.95 log CFU/g and an initial coliform of 2.72 log CFU/g (Table 2).…”

“…The rigid induction half-cavity formed between the top half microwave heating cap and bottom half induction base prevents expansion of the packaged foods when heated above 100 • C, thereby eliminating the need for overpressure, which is commonly produced by pressurized steam or water in conventional canning systems [10]. Recently, MAIH has been used for the cooking and pasteurization of shrimp for the first time in our research group [11]. Additionally, a previous piece of research also reported that after shrimps were processed by MAIH heating, the temperatures of all samples in the CPET container were within the range of 90-100 • C, as measured by thermal images; the uniform temperature distribution indicated that these heated shrimps underwent uniform heating [12].…”

Physicochemical and Microbial Quality of Prepackaged Shrimp Processed by a Scaled-Up Microwave-Assisted Induction Heating Technology

“…Under the heating condition of 90 • C, the first stage was maintained for 100 s, and in the second stage, processing time ranged from 10 to 50 s with increments of 10 s each (Table 1). The heating time design of this scaled-up MAIH study mainly refers to our previous research on experimental MAIH [13]. Our previous study demonstrated that the optimal cooking condition of white shrimp can be achieved by experimental MAIH at 130 • C for 80 s or 90 • C for 100 s [13].…”

“…The heating time design of this scaled-up MAIH study mainly refers to our previous research on experimental MAIH [13]. Our previous study demonstrated that the optimal cooking condition of white shrimp can be achieved by experimental MAIH at 130 • C for 80 s or 90 • C for 100 s [13]. Therefore, in order to reduce the number of repeated heating conditions, the first stage heating time was set to 80 s at 130 • C and 100 s at 90 • C; the second stage heating time (holding time) only gradually increased to determine whether the white shrimp was fully cooked.…”

“…The container is first placed in the induction half-cavity and then in the place of induction heating half-cavity and heated by the MAIH system [12]. Recently, this first generation and experimental MAIH was used to cook and pasteurize shrimp for the first time [13]. However, this was small-scale equipment with a sample capacity of approximately 350 mL, which cannot achieve an economical scale.…”