SUMMARYControlled samples from the same lots of asparagus, peas, lima beans, and spinach were quick‐frozen and canned by commercial methods and their vitamin B1and vitamin B2(G) content was compared with that of the raw vegetables. Fresh asparagus, peas, lima beans, and spinach were found to contain 65, 133, 67, and 36 International Units of vitamin B1, and 53, 70, 122, and 145 Bourquin‐Sherman units of vitamin B2(G) per 100 grams, respectively. Asparagus, peas, lima beans, and spinach retained 78, 97, 46, and 94 per cent of their vitamin Btand 95, 100, 84, and 91 per cent of their vitamin B2(G), respectively, when quick‐frozen; and 72, 60, 28, and 71 per cent of their vitamin B1and 98, 100, 70, and 45 per cent of their vitamin B2(G) content, respectively, when canned.The length of the blanching period may influence the vitamin B1and B2(G) content of quick‐frozen and canned vegetables. Because of the solubility of these vitamins in water, minimum blanching periods consistent with the requirements are recommended.In conclusion, it may be stated that both quick‐frozen and canned vegetables retain nutritionally significant percentages of vitamins B1and B2(G) and both types of preserved foods are good sources of these two water‐solub
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