Changes in Texture of Green Peas during Freezing and Frozen Storage

Abstract

The effects of freezing (still-air, air-blast, and Freon immersion freczing) and frozen storage (-5", -10" and -15°C for 0 to 48 wk) on texture of cooked frozen peas were examined. Peas frozen by a Frcon-12 immersion method with no appreciable damage to cell structure had firmer and more chewy sensory textural quality compared to those peas frozen by a slower freezing method.Sensory tcndcrness dccreased initially and then increased with storage time to the maximum storage times of 6 wk in -5°C storage, 16 wk in -10°C storage, and 48 wk in -15°C storage. Sensory chewiness increased initially, then remained constant with storage time cxccpt in -15°C storage. Gcnerally, the lower storage temperature resulted in less sensory chcwiness. The correlation coefficients (r) between sensory and objcctivc measurements for tenderness and chewiness were 0.76 and 0.88 (P < 0.05), respectively.

Pectin methylesterase catalyzed firming effects on low temperature blanched vegetables

“…Optimal preheating treatments have been evaluated, however, for some rehydrated fruit vegetables, including bell and Jalapeno peppers, snap bean pods and green beans (Howard, Burma, & Wagner, 1997;Huang & Thompson, 1989;Pala, 1982;Quintero-Ramos et al, 1998;Stolle-Smits et al, 2000). There is no published information on the use of LTLT treatments prior to freezing broccoli, peppers or sugar snap peas.…”

Changes in the Radical‐Scavenging Activity of Bitter Gourd (Momordica charantia L.) during Freezing and Frozen Storage with or without Blanching

“…Postprocessing temperature conditions and temperature fluctuations determine the rate of quality deterioration and the shelf life of frozen vegetables. Improper frozen storage causes evident changes in sensory characteristics that can influence consumer acceptability and also leads to products of reduced nutritive value, mainly in vitamin C. A considerable body of study on the different modes of quality degradation of different frozen vegetables has been published and reviewed in the earlier and recent literature (Kramer 1974; Labuza 1982; Martens 1986; Hung and Thompson 1989; Martins and Silva 1998). Vegetables are a major source of ascorbic acid, a nutrient that besides its vitamin action is valuable for its antioxidant effect.…”

Relevant Measurements of Green Pea Texture

“…Hung and Thompson (1989) found correlations r > 0.75 between Instron packability and sensory seed hardness and Instron packability and sensory chewiness. When they used single pea puncture testing, however, the correlation coefficient to sensory seed hardness was extremely low (r = 0.50).…”

“…From the literature we expected sensory seed hardness to be related with Instron measurements of processed peas because this measurement has been widely used in the past (Lee 1970;Hung and Thompson 1989;Forni et al 1991;Rutledge and Board 1980). However, this measurement had either a low or no correlation with sensory seed hardness or any of the other texture attributes ( Table 3).…”

“…The fact that sensory seed hardness was reported as one value but assessed, as the combined force required to bite completely through testa and cotyledon at first bite (Table 1) resulted in the introduction of the term cotyledon hardness in 1998. Schoonens (1977) and Hung and Thompson (1989) pointed out that it is very important to place a pea at the right angle to get a good measurement of sensory seed hardness. The testa is the first tissue to be penetrated and it has macrosclereids.…”