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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Healthy Processed Foods Research » Research » Publications at this Location » Publication #293930

Title: Peeling of tomatoes using novel infrared radiation heating technology

item LI, XUAN - University Of California
item Pan, Zhongli
item ATUNGULU, GRIFFITH - University Of California
item ZHENG, XIA - University Of California
item Wood, Delilah - De
item DELWICHE, MICHAEL - University Of California
item McHugh, Tara

Submitted to: Innovative Food Science and Emerging Technologies
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/23/2013
Publication Date: 1/6/2014
Citation: Li, X., Pan, Z., Atungulu, G., Zheng, X., Wood, D.F., Delwiche, M., Mchugh, T.H. 2014. Peeling of tomatoes using novel infrared radiation heating technology. Innovative Food Science and Emerging Technologies. 21:123-130. doi: 10.1016/j.ifset.2013.10.011.

Interpretive Summary: Peeling is an important process in food industry to produce premium quality canned fruits and vegetables. In this study, the effectiveness of IR dry-peeling of tomatoes was comprehensively investigated for two tomato peeling varieties with different physical attributes. Peeling performance and peeled product quality of IR heated tomatoes were evaluated and compared with tomatoes peeled by the conventional lye method. The impact of IR heating on biomechanical properties of tomato peels and microstructural changes in tomato epidermal and pericarp tissues were also studied. The findings demonstrated the effectiveness of the novel IR dry-peeling process for tomatoes.

Technical Abstract: The effectiveness of using infrared (IR) dry-peeling as an alternative process for peeling tomatoes without lye and water was studied. Compared to conventional lye peeling, IR dry-peeling using 30 s to 75 s heating time resulted in lower peeling loss (8.3% - 13.2% vs. 12.9% - 15.8%), thinner thickness of peeled-off skin (0.39 - 0.91 mm vs. 0.38 - 1.06 mm), and slightly firmer texture of peeled products (1.05 - 2.01 N vs. 0.96 - 1.40 N) while achieving a similar ease of peeling. IR heating increased the Young’s Modulus of tomato peels and reduced the peel adhesiveness, indicating the tomato peels to loosen, become brittle, and crack more easily. Also, IR heating resulted in melting of cuticular membrane, collapse of several cellular layers, and severe degradation of cell wall structures, which in turn caused peel separation. These findings demonstrated the effectiveness of the novel IR dry-peeling process for tomatoes.